Galaxies Gather at Great Distances

NASA Technical Reports Server (NTRS)

2006-01-01

[figure removed for brevity, see original site] Distant Galaxy Cluster Infrared Survey Poster [figure removed for brevity, see original site] [figure removed for brevity, see original site] Bird's Eye View Mosaic Bird's Eye View Mosaic with Clusters [figure removed for brevity, see original site] [figure removed for brevity, see original site] [figure removed for brevity, see original site] 9.1 Billion Light-Years 8.7 Billion Light-Years 8.6 Billion Light-Years

Astronomers have discovered nearly 300 galaxy clusters and groups, including almost 100 located 8 to 10 billion light-years away, using the space-based Spitzer Space Telescope and the ground-based Mayall 4-meter telescope at Kitt Peak National Observatory in Tucson, Ariz. The new sample represents a six-fold increase in the number of known galaxy clusters and groups at such extreme distances, and will allow astronomers to systematically study massive galaxies two-thirds of the way back to the Big Bang.

A mosaic portraying a bird's eye view of the field in which the distant clusters were found is shown at upper left. It spans a region of sky 40 times larger than that covered by the full moon as seen from Earth. Thousands of individual images from Spitzer's infrared array camera instrument were stitched together to create this mosaic. The distant clusters are marked with orange dots.

Close-up images of three of the distant galaxy clusters are shown in the adjoining panels. The clusters appear as a concentration of red dots near the center of each image. These images reveal the galaxies as they were over 8 billion years ago, since that's how long their light took to reach Earth and Spitzer's infrared eyes.

These pictures are false-color composites, combining ground-based optical images captured by the Mosaic-I camera on the Mayall 4-meter telescope at Kitt Peak, with infrared pictures taken by Spitzer's infrared array camera. Blue and green represent visible light at wavelengths of 0.4 microns and 0.8 microns, respectively, while red indicates infrared light at 4.5 microns.

Kitt Peak National Observatory is part of the National Optical Astronomy Observatory in Tuscon, Ariz.

A Search for Faint, Diffuse Halo Emission in Edge-On Galaxies with Spitzer/IRAC

NASA Astrophysics Data System (ADS)

Ashby, Matthew; Arendt, R. G.; Pipher, J. L.; Forrest, W. J.; Marengo, M.; Barmby, P.; Willner, S. P.; Stauffer, J. R.; Fazio, G. G.

2006-12-01

We present deep infrared mosaics of the nearby edge-on spiral galaxies NGC 891, 4244, 4565, and 5907. These data were acquired at 3.6, 4.5, 5.8, and 8.0 microns using the Infrared Array Camera aboard Spitzer as part of GTO program number 3. This effort is designed to detect the putative faint, diffuse emission from halos and thick disks of spiral galaxies in the near-mid infrared under the thermally stable, low-background conditions of space. These conditions in combination with the advantageous viewing angles presented by these well-known edge-on spirals provide arguably the best opportunity to characterize the halo/thick disk components of such galaxies in the infrared. In this contribution we describe our observations, data reduction techniques, corrections for artifacts in the data, and the modeling approach we applied to analyze this unique dataset. This work is based in part on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with NASA. Support for this work was provided by NASA through an award issued by JPL/Caltech.

Spitzer Digs Up Galactic Fossil

NASA Technical Reports Server (NTRS)

2004-01-01

[figure removed for brevity, see original site] Figure 1

[figure removed for brevity, see original site] Figure 2

This false-color image taken by NASA's Spitzer Space Telescope shows a globular cluster previously hidden in the dusty plane of our Milky Way galaxy. Globular clusters are compact bundles of old stars that date back to the birth of our galaxy, 13 or so billion years ago. Astronomers use these galactic 'fossils' as tools for studying the age and formation of the Milky Way.

Most clusters orbit around the center of the galaxy well above its dust-enshrouded disc, or plane, while making brief, repeated passes through the plane that each last about a million years. Spitzer, with infrared eyes that can see into the dusty galactic plane, first spotted the newfound cluster during its current pass. A visible-light image (inset of Figure 1) shows only a dark patch of sky.

The red streak behind the core of the cluster is a dust cloud, which may indicate the cluster's interaction with the Milky Way. Alternatively, this cloud may lie coincidentally along Spitzer's line of sight.

Follow-up observations with the University of Wyoming Infrared Observatory helped set the distance of the new cluster at about 9,000 light-years from Earth - closer than most clusters - and set the mass at the equivalent of 300,000 Suns. The cluster's apparent size, as viewed from Earth, is comparable to a grain of rice held at arm's length. It is located in the constellation Aquila.

Astronomers believe that this cluster may be one of the last in our galaxy to be uncovered.

This image composite was taken on April 21, 2004, by Spitzer's infrared array camera. It is composed of images obtained at four wavelengths: 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange) and 8 microns (red).

Galactic Fossil Found Behind Curtain of Dust In Figure 2, the image mosaic shows the same patch of sky in various wavelengths of light. While the visible-light image (left) shows a dark sky speckled with stars, infrared images (middle and right), reveal a never-before-seen bundle of stars, called a globular cluster. The left panel is from the California Institute of Technology's Digitized Sky Survey; the middle panel includes images from the NASA-funded Two Micron All-Sky Survey and the University of Wyoming Infrared Observatory (circle inset); and the right panel is from NASA's Spitzer Space Telescope.

The Two Micron All-Sky Survey false-color image was obtained using near-infrared wavelengths ranging from 1.3 to 2.2 microns. The University of Wyoming Observatory false-color image was captured on July 31, 2004, at wavelengths ranging from 1.2 to 2.2 microns. The Spitzer false-color image composite was taken on April 21, 2004, by its infrared array camera. It is composed of images obtained at four mid-infrared wavelengths: 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange) and 8 microns (red).

SPITZER IRAC PHOTOMETRY FOR TIME SERIES IN CROWDED FIELDS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Novati, S. Calchi; Beichman, C.; Gould, A.

We develop a new photometry algorithm that is optimized for the Infrared Array Camera (IRAC) Spitzer time series in crowded fields and that is particularly adapted to faint or heavily blended targets. We apply this to the 170 targets from the 2015 Spitzer microlensing campaign and present the results of three variants of this algorithm in an online catalog. We present detailed accounts of the application of this algorithm to two difficult cases, one very faint and the other very crowded. Several of Spitzer's instrumental characteristics that drive the specific features of this algorithm are shared by Kepler and WFIRST,more » implying that these features may prove to be a useful starting point for algorithms designed for microlensing campaigns by these other missions.« less

Towering Infernos

NASA Image and Video Library

2005-11-09

This majestic false-color image from NASA's Spitzer Space Telescope shows the "mountains" where stars are born. Dubbed "Mountains of Creation" by Spitzer scientists, these towering pillars of cool gas and dust are illuminated at their tips with light from warm embryonic stars. The new infrared picture is reminiscent of Hubble's iconic visible-light image of the Eagle Nebula, which also features a star-forming region, or nebula, that is being sculpted into pillars by radiation and winds from hot, massive stars. The pillars in the Spitzer image are part of a region called W5, in the Cassiopeia constellation 7,000 light-years away and 50 light-years across. They are more than 10 times in the size of those in the Eagle Nebula (shown to scale here). The Spitzer's view differs from Hubble's because infrared light penetrates dust, whereas visible light is blocked by it. In the Spitzer image, hundreds of forming stars (white/yellow) can seen for the first time inside the central pillar, and dozens inside the tall pillar to the left. Scientists believe these star clusters were triggered into existence by radiation and winds from an "initiator" star more than 10 times the mass of our Sun. This star is not pictured, but the finger-like pillars "point" toward its location above the image frame. The Spitzer picture also reveals stars (blue) a bit older than the ones in the pillar tips in the evacuated areas between the clouds. Scientists believe these stars were born around the same time as the massive initiator star not pictured. A third group of young stars occupies the bright area below the central pillar. It is not known whether these stars formed in a related or separate event. Some of the blue dots are foreground stars that are not members of this nebula. The red color in the Spitzer image represents organic molecules known as polycyclic aromatic hydrocarbons. These building blocks of life are often found in star-forming clouds of gas and dust. Like small dust grains, they are heated by the light from the young stars, then emit energy in infrared wavelengths. This image was taken by the infrared array camera on Spitzer. It is a 4-color composite of infrared light, showing emissions from wavelengths of 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange), and 8.0 microns (red). http://photojournal.jpl.nasa.gov/catalog/PIA03096

Spitzer Makes 'Invisible' Visible

NASA Technical Reports Server (NTRS)

2004-01-01

Hidden behind a shroud of dust in the constellation Cygnus is a stellar nursery called DR21, which is giving birth to some of the most massive stars in our galaxy. Visible light images reveal no trace of this interstellar cauldron because of heavy dust obscuration. In fact, visible light is attenuated in DR21 by a factor of more than 10,000,000,000,000,000,000,000,000,000,000,000,000,000 (ten thousand trillion heptillion).

New images from NASA's Spitzer Space Telescope allow us to peek behind the cosmic veil and pinpoint one of the most massive natal stars yet seen in our Milky Way galaxy. The never-before-seen star is 100,000 times as bright as the Sun. Also revealed for the first time is a powerful outflow of hot gas emanating from this star and bursting through a giant molecular cloud.

The colorful image is a large-scale composite mosaic assembled from data collected at a variety of different wavelengths. Views at visible wavelengths appear blue, near-infrared light is depicted as green, and mid-infrared data from the InfraRed Array Camera (IRAC) aboard NASA's Spitzer Space Telescope is portrayed as red. The result is a contrast between structures seen in visible light (blue) and those observed in the infrared (yellow and red). A quick glance shows that most of the action in this image is revealed to the unique eyes of Spitzer. The image covers an area about two times that of a full moon.

Serendipitous discovery of an infrared bow shock near PSR J1549–4848 with Spitzer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Zhongxiang; Kaplan, David L.; Slane, Patrick

2013-06-01

We report on the discovery of an infrared cometary nebula around PSR J1549–4848 in our Spitzer survey of a few middle-aged radio pulsars. Following the discovery, multi-wavelength imaging and spectroscopic observations of the nebula were carried out. We detected the nebula in Spitzer Infrared Array Camera 8.0, Multiband Imaging Photometer for Spitzer 24 and 70 μm imaging, and in Spitzer IRS 7.5-14.4 μm spectroscopic observations, and also in the Wide-field Infrared Survey Explorer all-sky survey at 12 and 22 μm. These data were analyzed in detail, and we find that the nebula can be described with a standard bow shockmore » shape, and that its spectrum contains polycyclic aromatic hydrocarbon and H{sub 2} emission features. However, it is not certain which object drives the nebula. We analyze the field stars and conclude that none of them can be the associated object because stars with a strong wind or mass ejection that usually produce bow shocks are much brighter than the field stars. The pulsar is approximately 15'' away from the region in which the associated object is expected to be located. In order to resolve the discrepancy, we suggest that a highly collimated wind could be emitted from the pulsar and produce the bow shock. X-ray imaging to detect the interaction of the wind with the ambient medium- and high-spatial resolution radio imaging to determine the proper motion of the pulsar should be carried out, which will help verify the association of the pulsar with the bow shock nebula.« less

Spitzer Reveals Stellar 'Family Tree'

NASA Technical Reports Server (NTRS)

2008-01-01

[figure removed for brevity, see original site] High resolution poster version

Generations of stars can be seen in this new infrared portrait from NASA's Spitzer Space Telescope. In this wispy star-forming region, called W5, the oldest stars can be seen as blue dots in the centers of the two hollow cavities (other blue dots are background and foreground stars not associated with the region). Younger stars line the rims of the cavities, and some can be seen as pink dots at the tips of the elephant-trunk-like pillars. The white knotty areas are where the youngest stars are forming. Red shows heated dust that pervades the region's cavities, while green highlights dense clouds.

W5 spans an area of sky equivalent to four full moons and is about 6,500 light-years away in the constellation Cassiopeia. The Spitzer picture was taken over a period of 24 hours.

Like other massive star-forming regions, such as Orion and Carina, W5 contains large cavities that were carved out by radiation and winds from the region's most massive stars. According to the theory of triggered star-formation, the carving out of these cavities pushes gas together, causing it to ignite into successive generations of new stars.

This image contains some of the best evidence yet for the triggered star-formation theory. Scientists analyzing the photo have been able to show that the ages of the stars become progressively and systematically younger with distance from the center of the cavities.

This is a three-color composite showing infrared observations from two Spitzer instruments. Blue represents 3.6-micron light and green shows light of 8 microns, both captured by Spitzer's infrared array camera. Red is 24-micron light detected by Spitzer's multiband imaging photometer.

New Infrared Emission Features and Spectral Variations in Ngc 7023

NASA Technical Reports Server (NTRS)

Werner, M. W.; Uchida, K. I.; Sellgren, K.; Marengo, M.; Gordon, K. D.; Morris, P. W.; Houck, J. R.; Stansberry, J. A.

2004-01-01

We observed the reflection nebula NGC 7023, with the Short-High module and the long-slit Short-Low and Long-Low modules of the Infrared Spectrograph on the Spitzer Space Telescope. We also present Infrared Array Camera (IRAC) and Multiband Imaging Photometer for Spitzer (MIPS) images of NGC 7023 at 3.6, 4.5, 8.0, and 24 m. We observe the aromatic emission features (AEFs) at 6.2, 7.7, 8.6, 11.3, and 12.7 m, plus a wealth of weaker features. We find new unidentified interstellar emission features at 6.7, 10.1, 15.8, 17.4, and 19.0 m. Possible identifications include aromatic hydrocarbons or nanoparticles of unknown mineralogy. We see variations in relative feature strengths, central wavelengths, and feature widths, in the AEFs and weaker emission features, depending on both distance from the star and nebular position (southeast vs. northwest).

A SPITZER VIEW OF STAR FORMATION IN THE CYGNUS X NORTH COMPLEX

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beerer, I. M.; Koenig, X. P.; Hora, J. L.

2010-09-01

We present new images and photometry of the massive star-forming complex Cygnus X obtained with the Infrared Array Camera (IRAC) and the Multiband Imaging Photometer for Spitzer (MIPS) on board the Spitzer Space Telescope. A combination of IRAC, MIPS, UKIRT Deep Infrared Sky Survey, and Two Micron All Sky Survey data are used to identify and classify young stellar objects (YSOs). Of the 8231 sources detected exhibiting infrared excess in Cygnus X North, 670 are classified as class I and 7249 are classified as class II. Using spectra from the FAST Spectrograph at the Fred L. Whipple Observatory and Hectospecmore » on the MMT, we spectrally typed 536 sources in the Cygnus X complex to identify the massive stars. We find that YSOs tend to be grouped in the neighborhoods of massive B stars (spectral types B0 to B9). We present a minimal spanning tree analysis of clusters in two regions in Cygnus X North. The fraction of infrared excess sources that belong to clusters with {>=}10 members is found to be 50%-70%. Most class II objects lie in dense clusters within blown out H II regions, while class I sources tend to reside in more filamentary structures along the bright-rimmed clouds, indicating possible triggered star formation.« less

VizieR Online Data Catalog: Young star forming region NGC 2264 Spitzer sources (Rapson+, 2014)

NASA Astrophysics Data System (ADS)

Rapson, V. A.; Pipher, J. L.; Gutermuth, R. A.; Megeath, S. T.; Allen, T. S.; Myers, P. C.; Allen, L. E.

2017-05-01

We utilize 3.6-8.0 um images of Mon OB1 East obtained with the Spitzer Space Telescope Infrared Array Camera (IRAC; Fazio et al. 2004ApJS..154...10F), 24 um images obtained with the Multi-Band Imaging Photometer (MIPS; Rieke et al. 2004ApJS..154...25R), along with 1-2.5 um NIR data from the Two Micron All Sky Survey (2MASS; Skrutskie et al. 2006AJ....131.1163S, Cat. VII/233) to classify YSOs. These YSOs in Mon OB1 East are classified as either protostars or stars with circumstellar disks by their infrared excess emission above photospheric emission. Spitzer data were gathered as part of two Guaranteed Time Observation programs and one additional program with the goal of studying clustered and distributed star formation throughout Mon OB1 East and comparing the results with those of other molecular clouds. Mon OB1 East was observed by Spitzer in 2004, 2007, and 2008 as part of the Guaranteed Time Observation programs 37 (IRAC data; PI: G. Fazio) and 58 (MIPS data; PI: G. Rieke), as well as program 40006 (IRAC+MIPS data; PI: G. Fazio). (1 data file).

NASA's Spitzer Space Telescope's Operational Mission Experience

NASA Technical Reports Server (NTRS)

Wilson, Robert K.; Scott, Charles P.

2006-01-01

New Generation of Detector Arrays(100 to 10,000 Gain in Capability over Previous Infrared Space Missions). IRAC: 256 x 256 pixel arrays operating at 3.6 microns, 4.5 microns, 5.8 microns, 8.0 microns. MIPS: Photometer with 3 sets of arrays operating at 24 microns, 70 microns and 160 microns. 128 x 128; 32 x 32 and 2 x 20 arrays. Spectrometer with 50-100 micron capabilities. IRS: 4 Array (128x128 pixel) Spectrograph, 4 -40 microns. Warm Launch Architecture: All other Infrared Missions launched with both the telescope and scientific instrument payload within the cryostat or Dewar. Passive cooling used to cool outer shell to approx.40 K. Cryogenic Boil-off then cools telescope to required 5.5K. Earth Trailing Heliocentric Orbit: Increased observing efficiency, simplification of observation planning, removes earth as heat source.

Spitzer Makes Invisible Visible

NASA Image and Video Library

2004-04-13

Hidden behind a shroud of dust in the constellation Cygnus is a stellar nursery called DR21, which is giving birth to some of the most massive stars in our galaxy. Visible light images reveal no trace of this interstellar cauldron because of heavy dust obscuration. In fact, visible light is attenuated in DR21 by a factor of more than 10,000,000,000,000,000,000,000,000,000,000,000,000,000 (ten thousand trillion heptillion). New images from NASA's Spitzer Space Telescope allow us to peek behind the cosmic veil and pinpoint one of the most massive natal stars yet seen in our Milky Way galaxy. The never-before-seen star is 100,000 times as bright as the Sun. Also revealed for the first time is a powerful outflow of hot gas emanating from this star and bursting through a giant molecular cloud. The colorful image is a large-scale composite mosaic assembled from data collected at a variety of different wavelengths. Views at visible wavelengths appear blue, near-infrared light is depicted as green, and mid-infrared data from the InfraRed Array Camera (IRAC) aboard NASA's Spitzer Space Telescope is portrayed as red. The result is a contrast between structures seen in visible light (blue) and those observed in the infrared (yellow and red). A quick glance shows that most of the action in this image is revealed to the unique eyes of Spitzer. The image covers an area about two times that of a full moon. http://photojournal.jpl.nasa.gov/catalog/PIA05734

The Space Infrared Interferometric Telescope (SPIRIT)

NASA Technical Reports Server (NTRS)

Rinehart, Stephen

2007-01-01

The Space Infrared Interferometric Telescope (SPIRIT) is a candidate NASA Origins Probe Mission. SPIRIT is a two-telescope Michelson interferometer covering wavelengths from 25-400 microns, providing simultaneously high spectral resolution and high angular resolution. With comparable sensitivity to Spitzer, but two orders of magnitude improvement in angular resolution, SPIRIT will enable us to address a wide array of compelling scientific questions, including how planetary systems form in disks and how new planets interact with the disk. Further, SPIRIT will lay the technological groundwork for an array of future interferometry missions with ambitious scientific goals, including the Terrestrial Planet Finder Interferometer / Darwin, and the Submillimeter Probe of the Evolution of Cosmic Structure.

The Space Infrared Interferometric Telescope (SPIRIT)

NASA Technical Reports Server (NTRS)

Rinehart, Stephen

2007-01-01

The Space Infrared Interferometric Telescope (SPIRIT) is a candidate NASA Origins Probe Mission. SPIRIT is a two-telescope Michelson interferometer covering wavelengths from 25-400 microns, providing simultaneously high spectral resolution and high angular resolution. With comparable sensitivity to Spitzer, but two orders of magnitude improvement in angular resolution, SPIRIT will enable us to address a wide array of compelling scientific questions, including how planetary systems form in disks and how new planets interact with the disk. Further, SPIRIT will lay the technological groundwork for an array of future interferometry missions with ambitious scientific goals, including the Terrestrial Planet Finder Interferometer/Darwin, and the Submillimeter Probe of the Evolution of Cosmic Structure.

Omega Centauri Looks Radiant in Infrared

NASA Technical Reports Server (NTRS)

2008-01-01

[figure removed for brevity, see original site] Poster Version

A cluster brimming with millions of stars glistens like an iridescent opal in this image from NASA's Spitzer Space Telescope. Called Omega Centauri, the sparkling orb of stars is like a miniature galaxy. It is the biggest and brightest of the 150 or so similar objects, called globular clusters, that orbit around the outside of our Milky Way galaxy. Stargazers at southern latitudes can spot the stellar gem with the naked eye in the constellation Centaurus.

Globular clusters are some of the oldest objects in our universe. Their stars are over 12 billion years old, and, in most cases, formed all at once when the universe was just a toddler. Omega Centauri is unusual in that its stars are of different ages and possess varying levels of metals, or elements heavier than boron. Astronomers say this points to a different origin for Omega Centauri than other globular clusters: they think it might be the core of a dwarf galaxy that was ripped apart and absorbed by our Milky Way long ago.

In this new view of Omega Centauri, Spitzer's infrared observations have been combined with visible-light data from the National Science Foundation's Blanco 4-meter telescope at Cerro Tololo Inter-American Observatory in Chile. Visible-light data with a wavelength of .55 microns is colored blue, 3.6-micron infrared light captured by Spitzer's infrared array camera is colored green and 24-micron infrared light taken by Spitzer's multiband imaging photometer is colored red.

Where green and red overlap, the color yellow appears. Thus, the yellow and red dots are stars revealed by Spitzer. These stars, called red giants, are more evolved, larger and dustier. The stars that appear blue were spotted in both visible and 3.6-micron-, or near-, infrared light. They are less evolved, like our own sun. Some of the red spots in the picture are distant galaxies beyond our own.

Spitzer found very little dust around any but the most luminous, coolest red giants, implying that the dimmer red giants do not form significant amounts of dust. The space between the stars in Omega Centauri was also found to lack dust, which means the dust is rapidly destroyed or leaves the cluster.

A New Large-Well 1024x1024 Si:As Detector for the Mid-Infrared

NASA Technical Reports Server (NTRS)

Mainzer, Amanda K.; Hong, John H.; Stapelbroek, M. G.; Hogue, Henry; Molyneux, Dale; Ressler, Michael E.; Watkins, Ernie; Reekstin, John; Werner, Mike; Young, Erick

2005-01-01

We present a description of a new 1024x1024 Si:As array designed for ground-based use from 5 - 28 microns. With a maximum well depth of 5e6 electrons, this device brings large-format array technology to bear on ground-based mid-infrared programs, allowing entry to the mega-pixel realm previously only accessible to the near-IR. The multiplexer design features switchable gain, a 256x256 windowing mode for extremely bright sources, and it is two-edge buttable. The device is currently in its final design phase at DRS in Cypress, CA. We anticipate completion of the foundry run in October 2005. This new array will enable wide field, high angular resolution ground-based follow up of targets found by space-based missions such as the Spitzer Space Telescope and the Wide-field Infrared Survey Explorer (WISE).

Spitzer Digs Up Galactic Fossil

NASA Image and Video Library

2004-10-12

This false-color image taken by NASA Spitzer Space Telescope shows a globular cluster previously hidden in the dusty plane of our Milky Way galaxy. Globular clusters are compact bundles of old stars that date back to the birth of our galaxy, 13 or so billion years ago. Astronomers use these galactic "fossils" as tools for studying the age and formation of the Milky Way. Most clusters orbit around the center of the galaxy well above its dust-enshrouded disc, or plane, while making brief, repeated passes through the plane that each last about a million years. Spitzer, with infrared eyes that can see into the dusty galactic plane, first spotted the newfound cluster during its current pass. A visible-light image (inset of Figure 1) shows only a dark patch of sky. The red streak behind the core of the cluster is a dust cloud, which may indicate the cluster's interaction with the Milky Way. Alternatively, this cloud may lie coincidentally along Spitzer's line of sight. Follow-up observations with the University of Wyoming Infrared Observatory helped set the distance of the new cluster at about 9,000 light-years from Earth - closer than most clusters - and set the mass at the equivalent of 300,000 Suns. The cluster's apparent size, as viewed from Earth, is comparable to a grain of rice held at arm's length. It is located in the constellation Aquila. Astronomers believe that this cluster may be one of the last in our galaxy to be uncovered. This image composite was taken on April 21, 2004, by Spitzer's infrared array camera. It is composed of images obtained at four wavelengths: 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange) and 8 microns (red). http://photojournal.jpl.nasa.gov/catalog/PIA06928

Young Stars Emerge from Orion Head

NASA Image and Video Library

2007-05-17

This image from NASA's Spitzer Space Telescope shows infant stars "hatching" in the head of the hunter constellation, Orion. Astronomers suspect that shockwaves from a supernova explosion in Orion's head, nearly three million years ago, may have initiated this newfound birth . The region featured in this Spitzer image is called Barnard 30. It is located approximately 1,300 light-years away and sits on the right side of Orion's "head," just north of the massive star Lambda Orionis. Wisps of red in the cloud are organic molecules called polycyclic aromatic hydrocarbons. These molecules are formed anytime carbon-based materials are burned incompletely. On Earth, they can be found in the sooty exhaust from automobile and airplane engines. They also coat the grills where charcoal-broiled meats are cooked. This image shows infrared light captured by Spitzer's infrared array camera. Light with wavelengths of 8 and 5.8 microns (red and orange) comes mainly from dust that has been heated by starlight. Light of 4.5 microns (green) shows hot gas and dust; and light of 3.6 microns (blue) is from starlight. http://photojournal.jpl.nasa.gov/catalog/PIA09412

Young Stars Emerge from Orion's Head

NASA Technical Reports Server (NTRS)

2007-01-01

This image from NASA's Spitzer Space Telescope shows infant stars 'hatching' in the head of the hunter constellation, Orion. Astronomers suspect that shockwaves from a supernova explosion in Orion's head, nearly three million years ago, may have initiated this newfound birth

The region featured in this Spitzer image is called Barnard 30. It is located approximately 1,300 light-years away and sits on the right side of Orion's 'head,' just north of the massive star Lambda Orionis.

Wisps of red in the cloud are organic molecules called polycyclic aromatic hydrocarbons. These molecules are formed anytime carbon-based materials are burned incompletely. On Earth, they can be found in the sooty exhaust from automobile and airplane engines. They also coat the grills where charcoal-broiled meats are cooked.

This image shows infrared light captured by Spitzer's infrared array camera. Light with wavelengths of 8 and 5.8 microns (red and orange) comes mainly from dust that has been heated by starlight. Light of 4.5 microns (green) shows hot gas and dust; and light of 3.6 microns (blue) is from starlight.

Analysis of Secondary Eclipse Observations of Exoplanet WASP-34b

NASA Astrophysics Data System (ADS)

Challener, Ryan; Harrington, Joseph; Garland, Justin; Cubillos, Patricio; Blecic, Jasmina; Smalley, Barry

2014-11-01

WASP-34b is a short-period exoplanet with a mass of 0.59 +/- 0.01 Jupiter masses orbiting a sun-like star with a period of 4.3177 days and an eccentricity of 0.038 +/- 0.012 (Smalley, 2010). We observed WASP-34b using the 3.6 and 4.5 micron channels of the Infrared Array Camera aboard the Spitzer Space Telescope in 2010 (Program 60003). We present eclipse-depth measurements, estimates of infrared brightness temperatures, and refine the orbit using our secondary eclipse measurements. Spitzer is operated by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. This work was supported by NASA Planetary Atmospheres grant NNX12AI69G and NASA Astrophysics Data Analysis Program grant NNX13AF38G. JB holds a NASA Earth and Space Science Fellowship.

Stellar Jewels Shine in New Spitzer Image

NASA Technical Reports Server (NTRS)

2004-01-01

One of the most prolific birthing grounds in our Milky Way galaxy, a nebula called RCW 49, is exposed in superb detail for the first time in this new image from NASA's Spitzer Space Telescope. Located 13,700 light-years away in the southern constellation Centaurus, RCW 49 is a dark and dusty stellar nursery that houses more than 2,200 stars.

Because many of the stars in RCW 49 are deeply embedded in plumes of dust, they cannot be seen at visible wavelengths. When viewed with Spitzer's infrared eyes, however, RCW 49 becomes transparent. Like cracking open a quartz rock to discover its jewels inside, the nebula's newborn stars have been dramatically exposed.

This image taken by Spitzer's infrared array camera highlights the nebula's older stars (blue stars in center pocket), its gas filaments (green) and dusty tendrils (pink). Speckled throughout the murky clouds are more than 300 never-before-seen newborn stars.

Astronomers are interested in further studying these newfound proto-stars because they offer a fresh look at star formation in our own galaxy.

This image was taken on Dec. 23, 2003, and is composed of photographs obtained at four wavelengths: 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange) and 8 microns (red).

Stellar Jewels Shine in New Spitzer Image

NASA Image and Video Library

2004-05-27

One of the most prolific birthing grounds in our Milky Way galaxy, a nebula called RCW 49, is exposed in superb detail for the first time in this new image from NASA's Spitzer Space Telescope. Located 13,700 light-years away in the southern constellation Centaurus, RCW 49 is a dark and dusty stellar nursery that houses more than 2,200 stars. Because many of the stars in RCW 49 are deeply embedded in plumes of dust, they cannot be seen at visible wavelengths. When viewed with Spitzer's infrared eyes, however, RCW 49 becomes transparent. Like cracking open a quartz rock to discover its jewels inside, the nebula's newborn stars have been dramatically exposed. This image taken by Spitzer's infrared array camera highlights the nebula's older stars (blue stars in center pocket), its gas filaments (green) and dusty tendrils (pink). Speckled throughout the murky clouds are more than 300 never-before-seen newborn stars. Astronomers are interested in further studying these newfound proto-stars because they offer a fresh look at star formation in our own galaxy. This image was taken on Dec. 23, 2003, and is composed of photographs obtained at four wavelengths: 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange) and 8 microns (red). http://photojournal.jpl.nasa.gov/catalog/PIA05989

Observatories Combine to Crack Open the Crab Nebula

NASA Image and Video Library

2017-12-08

Astronomers have produced a highly detailed image of the Crab Nebula, by combining data from telescopes spanning nearly the entire breadth of the electromagnetic spectrum, from radio waves seen by the Karl G. Jansky Very Large Array (VLA) to the powerful X-ray glow as seen by the orbiting Chandra X-ray Observatory. And, in between that range of wavelengths, the Hubble Space Telescope's crisp visible-light view, and the infrared perspective of the Spitzer Space Telescope. This composite image of the Crab Nebula, a supernova remnant, was assembled by combining data from five telescopes spanning nearly the entire breadth of the electromagnetic spectrum: the Very Large Array, the Spitzer Space Telescope, the Hubble Space Telescope, the XMM-Newton Observatory, and the Chandra X-ray Observatory. Credits: NASA, ESA, NRAO/AUI/NSF and G. Dubner (University of Buenos Aires) #nasagoddard #space #science

'Peony Nebula' Star Settles for Silver Medal

NASA Technical Reports Server (NTRS)

2008-01-01

[figure removed for brevity, see original site] [figure removed for brevity, see original site] Poster Version Movie

If our galaxy, the Milky Way, were to host its own version of the Olympics, the title for the brightest known star would go to a massive star called Eta Carina. However, a new runner-up now the second-brightest star in our galaxy has been discovered in the galaxy's dusty and frenzied interior. This image from NASA's Spitzer Space Telescope shows the new silver medalist, circled in the inset above, in the central region of our Milky Way.

Dubbed the 'Peony nebula' star, this blazing ball of gas shines with the equivalent light of 3.2 million suns. The reigning champ, Eta Carina, produces the equivalent of 4.7 million suns worth of light though astronomers say these estimates are uncertain, and it's possible that the Peony nebula star could be even brighter than Eta Carina.

If the Peony star is so bright, why doesn't it stand out more in this view? The answer is dust. This star is located in a very dusty region jam packed with stars. In fact, there could be other super bright stars still hidden deep in the stellar crowd. Spitzer's infrared eyes allowed it to pierce the dust and assess the Peony nebula star's true brightness. Likewise, infrared data from the European Southern Observatory's New Technology Telescope in Chile were integral in calculating the Peony nebula star's luminosity.

The Peony nebula, which surrounds the Peony nebular star, is the reddish cloud of dust in and around the white circle.

The movie begins by showing a stretch of the dusty and frenzied central region of our Milky Way galaxy. It then zooms in to reveal the 'Peony nebula' star the new second-brightest star in the Milky Way, discovered in part by NASA's Spitzer Space Telescope.

This is a three-color composite showing infrared observations from two Spitzer instruments. Blue represents 3.6-micron light and green shows light of 8 microns, both captured by Spitzer's infrared array camera. Red is 24-micron light detected by Spitzer's multiband imaging photometer.

Recent SPIRITS discoveries of Infrared Transients and Variables with Spitzer/IRAC

NASA Astrophysics Data System (ADS)

Jencson, J. E.; Kasliwal, M. M.; Adams, S.; Cook, D.; Tinyanont, S.; Kwan, S.; Prince, T.; Lau, R. M.; Perley, D.; Masci, F.; Helou, G.; Armus, L.; Surace, J.; Dyk, S. D. Van; Cody, A.; Boyer, M. L.; Bond, H. E.; Monson, A.; Bally, J.; Khan, R.; Levesque, E.; Fox, O.; Williams, R.; Whitelock, P. A.; Mohamed, S.; Gehrz, R. D.; Amodeo, S.; Shenoy, D.; Carlon, R.; Cass, A.; Corgan, D.; Dykhoff, D.; Faella, J.; Gburek, T.; Smith, N.; Cantiello, M.; Langer, N.; Ofek, E.; Johansson, J.; Parthasarathy, M.; Hsiao, E.; Phillips, M.; Morrell, N.; Gonzalez, C.; Contreras, C.

2018-04-01

We report the discoveries of mid-infrared transients/strong variables found in the course of the Spitzer InfraRed Intensive Transients Survey (SPIRITS) using Spitzer Early Release Data (ATel #6644, #7929, #8688, #8940, #9434, #10171, #10172, #10488, #10903).

VizieR Online Data Catalog: The hot Jupiter Kepler-13Ab planet's occultation (Shporer+, 2014)

NASA Astrophysics Data System (ADS)

Shporer, A.; O'Rourke, J. G.; Knutson, H. A.; Szabo, G. M.; Zhao, M.; Burrows, A.; Fortney, J.; Agol, E.; Cowan, N. B.; Desert, J.-M.; Howard, A. W.; Isaacson, H.; Lewis, N. K.; Showman, A. P.; Todorov, K. O.

2017-07-01

Here we carry out an atmospheric characterization of Kepler-13Ab by measuring its occultation in four different wavelength bands, from the infrared (IR; Spitzer/Infrared array camera (IRAC) 4.5 um and 3.6 um), through the near-IR (NIR; Ks band), to the optical (Kepler). We also analyze the Kepler phase curve and obtain Keck/high-resolution echelle spectrometer (HIRES) spectra that result in revised parameters for the objects in the system. (4 data files).

M33: A Close Neighbor Reveals its True Size and Splendor (3-color composite)

NASA Technical Reports Server (NTRS)

2009-01-01

One of our closest galactic neighbors shows its awesome beauty in this new image from NASA's Spitzer Space Telescope. M33, also known as the Triangulum Galaxy, is a member of what's known as our Local Group of galaxies. Along with our own Milky Way, this group travels together in the universe, as they are gravitationally bound. In fact, M33 is one of the few galaxies that is moving toward the Milky Way despite the fact that space itself is expanding, causing most galaxies in the universe to grow farther and farther apart.

When viewed with Spitzer's infrared eyes, this elegant spiral galaxy sparkles with color and detail. Stars appear as glistening blue gems (several of which are actually foreground stars in our own galaxy), while dust rich in organic molecules glows green. The diffuse orange-red glowing areas indicate star-forming regions, while small red flecks outside the spiral disk of M33 are most likely distant background galaxies. But not only is this new image beautiful, it also shows M33 to be surprising large bigger than its visible-light appearance would suggest. With its ability to detect cold, dark dust, Spitzer can see emission from cooler material well beyond the visible range of M33's disk. Exactly how this cold material moved outward from the galaxy is still a mystery, but winds from giant stars or supernovas may be responsible.

M33 is located about 2.9 million light-years away in the constellation Triangulum. This is a three-color composite image showing infrared observations from two of Spitzer instruments. Blue represents combined 3.6- and 4.5-micron light and green shows light of 8 microns, both captured by Spitzer's infrared array camera. Red is 24-micron light detected by Spitzer's multiband imaging photometer.

VizieR Online Data Catalog: Ccompact group galaxies UV and IR SFR (Lenkic+, 2016)

NASA Astrophysics Data System (ADS)

Lenkic, L.; Tzanavaris, P.; Gallagher, S. C.; Desjardins, T. D.; Walker, L. M.; Johnson, K. E.; Fedotov, K.; Charlton, J.; Hornschemeier, A. E.; Durrell, P. R.; Gronwall, C.

2017-07-01

The sample of CGs studied here is the same sample studied by Walker et al. (2012AJ....143...69W) of 49 CGs: 33 Hickson Compact Groups and 16 Redshift Survey Compact Groups (RSCGs). The RSCG catalogue of 89 CGs was constructed by Barton et al. (1996AJ....112..871B). The data used in this study originated from 'fill-in' observations with UVOT's three UV filters (uvw2, uvm2, uvw1) as well as the bluest optical filter (u). All UV data (PI: Tzanavaris) were downloaded from the Swift archive. The Spitzer Infrared Array Camera images for our sample of CGs are archival data presented by Walker et al. (2012AJ....143...69W) Spitzer MIPS (24um) data were obtained from the Spitzer Heritage Archive. (4 data files).

Morphology of Our Galaxy Twin

NASA Image and Video Library

2004-06-28

NASA's Spitzer Space Telescope has captured these infrared images of a nearby spiral galaxy that resembles our own Milky Way. The targeted galaxy, known as NGC 7331 and sometimes referred to as our galaxy's twin, is found in the constellation Pegasus at a distance of 50 million light-years. This inclined galaxy was discovered in 1784 by William Herschel, who also discovered infrared light. The evolution of this galaxy is a story that depends significantly on the amount and distribution of gas and dust, the locations and rates of star formation, and on how the energy from star formation is recycled by the local environment. The new Spitzer images are allowing astronomers to "read" this story by dissecting the galaxy into its separate components. The image, measuring 12.6 by 8.2 arcminutes, was obtained by Spitzer's infrared array camera. It is a four-color composite of invisible light, showing emissions from wavelengths of 3.6 microns (blue), 4.5 microns (green), 5.8 microns (yellow) and 8.0 microns (red). These wavelengths are roughly 10 times longer than those seen by the human eye. The infrared light seen in this image originates from two very different sources. At shorter wavelengths (3.6 to 4.5 microns), the light comes mainly from stars, particularly ones that are older and cooler than our Sun. This starlight fades at longer wavelengths (5.8 to 8.0 microns), where instead we see the glow from clouds of interstellar dust. This dust consists mainly of a variety of carbon-based organic molecules known collectively as polycyclic aromatic hydrocarbons. Wherever these compounds are found, there will also be dust granules and gas, which provide a reservoir of raw materials for future star formation. One feature that stands out in the Spitzer image is the ring of actively forming stars that surrounds the galaxy center (yellow). This ring, with a radius of nearly 20,000 light-years, is invisible at shorter wavelengths, yet has been detected at sub-millimeter and radio wavelengths. It is made up in large part of polycyclic aromatic hydrocarbons. Spitzer measurements suggest that the ring contains enough gas to produce four billion stars like the Sun. Three other galaxies are seen below NGC 7331, all about 10 times farther away. From left to right are NGC 7336, NGC 7335 and NGC 7337. The blue dots scattered throughout the images are foreground stars in the Milky Way; the red ones are galaxies that are even more distant. The Spitzer observations of NGC 7331 are part of a large 500-hour science project, known as the Spitzer Infrared Nearby Galaxy Survey, which will comprehensively study 75 nearby galaxies with infrared imaging and spectroscopy. http://photojournal.jpl.nasa.gov/catalog/PIA06322

Morphology of Our Galaxy's 'Twin'

NASA Technical Reports Server (NTRS)

2004-01-01

NASA's Spitzer Space Telescope has captured these infrared images of a nearby spiral galaxy that resembles our own Milky Way. The targeted galaxy, known as NGC 7331 and sometimes referred to as our galaxy's twin, is found in the constellation Pegasus at a distance of 50 million light-years. This inclined galaxy was discovered in 1784 by William Herschel, who also discovered infrared light.

The evolution of this galaxy is a story that depends significantly on the amount and distribution of gas and dust, the locations and rates of star formation, and on how the energy from star formation is recycled by the local environment. The new Spitzer images are allowing astronomers to 'read' this story by dissecting the galaxy into its separate components.

The image, measuring 12.6 by 8.2 arcminutes, was obtained by Spitzer's infrared array camera. It is a four-color composite of invisible light, showing emissions from wavelengths of 3.6 microns (blue), 4.5 microns (green), 5.8 microns (yellow) and 8.0 microns (red). These wavelengths are roughly 10 times longer than those seen by the human eye.

The infrared light seen in this image originates from two very different sources. At shorter wavelengths (3.6 to 4.5 microns), the light comes mainly from stars, particularly ones that are older and cooler than our Sun. This starlight fades at longer wavelengths (5.8 to 8.0 microns), where instead we see the glow from clouds of interstellar dust. This dust consists mainly of a variety of carbon-based organic molecules known collectively as polycyclic aromatic hydrocarbons. Wherever these compounds are found, there will also be dust granules and gas, which provide a reservoir of raw materials for future star formation.

One feature that stands out in the Spitzer image is the ring of actively forming stars that surrounds the galaxy center (yellow). This ring, with a radius of nearly 20,000 light-years, is invisible at shorter wavelengths, yet has been detected at sub-millimeter and radio wavelengths. It is made up in large part of polycyclic aromatic hydrocarbons. Spitzer measurements suggest that the ring contains enough gas to produce four billion stars like the Sun.

Three other galaxies are seen below NGC 7331, all about 10 times farther away. From left to right are NGC 7336, NGC 7335 and NGC 7337. The blue dots scattered throughout the images are foreground stars in the Milky Way; the red ones are galaxies that are even more distant.

The Spitzer observations of NGC 7331 are part of a large 500-hour science project, known as the Spitzer Infrared Nearby Galaxy Survey, which will comprehensively study 75 nearby galaxies with infrared imaging and spectroscopy.

VizieR Online Data Catalog: Bright white dwarfs IRAC photometry (Barber+, 2016)

NASA Astrophysics Data System (ADS)

Barber, S. D.; Belardi, C.; Kilic, M.; Gianninas, A.

2017-07-01

Mid-infrared photometry, like the 3.4 and 4.6um photometry available from WISE, is necessary to detect emission from a debris disc orbiting a WD. WISE, however, has poor spatial resolution (6 arcsec beam size) and is known to have a 75 per cent false positive rate for detecting dusty discs around WDs fainter than 14.5(15) mag in W1(W2) (Barber et al. (2014ApJ...786...77B). To mitigate this high rate of spurious detections, we compile higher spatial resolution archival data from the InfraRed Array Camera (IRAC) on the Spitzer Space Telescope. We query the Spitzer Heritage Archive for any observations within 10 arcsec of the 1265 WDs from Gianninas et al. (2011, Cat. J/ApJ/743/138) and find 907 Astronomical Observing Requests (AORs) for 381 WDs. (1 data file).

Baby Picture of our Solar System

NASA Technical Reports Server (NTRS)

2007-01-01

[figure removed for brevity, see original site] [figure removed for brevity, see original site] [figure removed for brevity, see original site] Click on image for Poster VersionClick on image for Visible Light ImageClick on image for Animation

A rare, infrared view of a developing star and its flaring jets taken by NASA's Spitzer Space Telescope shows us what our own solar system might have looked like billions of years ago. In visible light, this star and its surrounding regions are completely hidden in darkness.

Stars form out of spinning clouds, or envelopes, of gas and dust. As the envelopes flatten and collapse, jets of gas stream outward and a swirling disk of planet-forming material takes shape around the forming star. Eventually, the envelope and jets disappear, leaving a newborn star with a suite of planets. This process takes millions of years.

The Spitzer image shows a developing sun-like star, called L1157, that is only thousands of years old (for comparison, our solar system is around 4.5 billion years old). Why is the young system only visible in infrared light? The answer has to do with the fact that stars are born in the darkest and dustiest corners of space, where little visible light can escape. But the heat, or infrared light, of an object can be detected through the dust.

In Spitzer's infrared view of L1157, the star itself is hidden but its envelope is visible in silhouette as a thick black bar. While Spitzer can peer through this region's dust, it cannot penetrate the envelope itself. Hence, the envelope appears black. The thickest part of the envelope can be seen as the black line crossing the giant jets. This L1157 portrait provides the first clear look at stellar envelope that has begun to flatten.

The color white shows the hottest parts of the jets, with temperatures around 100 degrees Celsius (212 degrees Fahrenheit). Most of the material in the jets, seen in orange, is roughly zero degrees on the Celsius and Fahrenheit scales.

The reddish haze all around the picture is dust. The white dots are other stars, mostly in the background.

L1157 is located 800 light-years away in the constellation Cepheus.

This image was taken by Spitzer's infrared array camera. Infrared light of 8 microns is colored red; 4.5-micron infrared light is green; and 3.6-micron infrared light is blue.

The visible-light picture is from the Palomar Observatory-Space Telescope Science Institute Digitized Sky Survey. Blue visible light is blue; red visible light is green, and near-infrared light is red.

The artist's animation begins by showing a dark and dusty corner of space where little visible light can escape. The animation then transitions to the infrared view taken by NASA's Spitzer Space Telescope, revealing the embryonic star and its dramatic jets.

M33: A Close Neighbor Reveals its True Size and Splendor

NASA Technical Reports Server (NTRS)

2009-01-01

One of our closest galactic neighbors shows its awesome beauty in this new image from NASA's Spitzer Space Telescope. M33, also known as the Triangulum Galaxy, is a member of what's known as our Local Group of galaxies. Along with our own Milky Way, this group travels together in the universe, as they are gravitationally bound. In fact, M33 is one of the few galaxies that is moving toward the Milky Way despite the fact that space itself is expanding, causing most galaxies in the universe to grow farther and farther apart.

When viewed with Spitzer's infrared eyes, this elegant spiral galaxy sparkles with color and detail. Stars appear as glistening blue gems (many of which are actually foreground stars in our own galaxy), while dust in the spiral disk of the galaxy glows pink and red. But not only is this new image beautiful, it also shows M33 to be surprising large bigger than its visible-light appearance would suggest. With its ability to detect cold, dark dust, Spitzer can see emission from cooler material well beyond the visible range of M33's disk. Exactly how this cold material moved outward from the galaxy is still a mystery, but winds from giant stars or supernovas may be responsible.

M33 is located about 2.9 million light-years away in the constellation Triangulum. This composite image was taken by Spitzer's infrared array camera. The color blue indicates infrared light of 3.6 microns, green shows 4.5-micron light, and red 8.0 microns.

The NASA Spitzer Space Telescope.

PubMed

Gehrz, R D; Roellig, T L; Werner, M W; Fazio, G G; Houck, J R; Low, F J; Rieke, G H; Soifer, B T; Levine, D A; Romana, E A

2007-01-01

The National Aeronautics and Space Administration's Spitzer Space Telescope (formerly the Space Infrared Telescope Facility) is the fourth and final facility in the Great Observatories Program, joining Hubble Space Telescope (1990), the Compton Gamma-Ray Observatory (1991-2000), and the Chandra X-Ray Observatory (1999). Spitzer, with a sensitivity that is almost three orders of magnitude greater than that of any previous ground-based and space-based infrared observatory, is expected to revolutionize our understanding of the creation of the universe, the formation and evolution of primitive galaxies, the origin of stars and planets, and the chemical evolution of the universe. This review presents a brief overview of the scientific objectives and history of infrared astronomy. We discuss Spitzer's expected role in infrared astronomy for the new millennium. We describe pertinent details of the design, construction, launch, in-orbit checkout, and operations of the observatory and summarize some science highlights from the first two and a half years of Spitzer operations. More information about Spitzer can be found at http://spitzer.caltech.edu/.

Stellar Snowflake Cluster

NASA Technical Reports Server (NTRS)

2005-01-01

[figure removed for brevity, see original site] Figure 1 Stellar Snowflake Cluster Combined Image [figure removed for brevity, see original site] Figure 2 Infrared Array CameraFigure 3 Multiband Imaging Photometer

Newborn stars, hidden behind thick dust, are revealed in this image of a section of the Christmas Tree cluster from NASA's Spitzer Space Telescope, created in joint effort between Spitzer's infrared array camera and multiband imaging photometer instruments.

The newly revealed infant stars appear as pink and red specks toward the center of the combined image (fig. 1). The stars appear to have formed in regularly spaced intervals along linear structures in a configuration that resembles the spokes of a wheel or the pattern of a snowflake. Hence, astronomers have nicknamed this the 'Snowflake' cluster.

Star-forming clouds like this one are dynamic and evolving structures. Since the stars trace the straight line pattern of spokes of a wheel, scientists believe that these are newborn stars, or 'protostars.' At a mere 100,000 years old, these infant structures have yet to 'crawl' away from their location of birth. Over time, the natural drifting motions of each star will break this order, and the snowflake design will be no more.

While most of the visible-light stars that give the Christmas Tree cluster its name and triangular shape do not shine brightly in Spitzer's infrared eyes, all of the stars forming from this dusty cloud are considered part of the cluster.

Like a dusty cosmic finger pointing up to the newborn clusters, Spitzer also illuminates the optically dark and dense Cone nebula, the tip of which can be seen towards the bottom left corner of each image.

This combined image shows the presence of organic molecules mixed with dust as wisps of green, which have been illuminated by nearby star formation. The larger yellowish dots neighboring the baby red stars in the Snowflake Cluster are massive stellar infants forming from the same cloud. The blue dots sprinkled across the image represent older Milky Way stars at various distances along this line of sight. This image is a five-channel, false-color composite, showing emission from wavelengths of 3.6 and 4.5 microns (blue), 5.8 microns (cyan), 8 microns (green), and 24 microns (red).

The top right (fig. 2) image from the infrared array camera show that the nebula is still actively forming stars. The wisps of red (represented as green in the combined image) are organic molecules mixed with dust, which has been illuminated by nearby star formation. The infrared array camera picture is a four-channel, false-color composite, showing emission from wavelengths of 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange) and 8.0 microns (red).

The bottom right image (fig. 3) from the multiband imaging photometer shows the colder dust of the nebula and unwraps the youngest stellar babies from their dusty covering. This is a false-color image showing emission at 24 microns (red).

Comets Kick up Dust in Helix Nebula

NASA Technical Reports Server (NTRS)

2007-01-01

This infrared image from NASA's Spitzer Space Telescope shows the Helix nebula, a cosmic starlet often photographed by amateur astronomers for its vivid colors and eerie resemblance to a giant eye.

The nebula, located about 700 light-years away in the constellation Aquarius, belongs to a class of objects called planetary nebulae. Discovered in the 18th century, these colorful beauties were named for their resemblance to gas-giant planets like Jupiter.

Planetary nebulae are the remains of stars that once looked a lot like our sun. When sun-like stars die, they puff out their outer gaseous layers. These layers are heated by the hot core of the dead star, called a white dwarf, and shine with infrared and visible colors. Our own sun will blossom into a planetary nebula when it dies in about five billion years.

In Spitzer's infrared view of the Helix nebula, the eye looks more like that of a green monster's. Infrared light from the outer gaseous layers is represented in blues and greens. The white dwarf is visible as a tiny white dot in the center of the picture. The red color in the middle of the eye denotes the final layers of gas blown out when the star died.

The brighter red circle in the very center is the glow of a dusty disk circling the white dwarf (the disk itself is too small to be resolved). This dust, discovered by Spitzer's infrared heat-seeking vision, was most likely kicked up by comets that survived the death of their star. Before the star died, its comets and possibly planets would have orbited the star in an orderly fashion. But when the star blew off its outer layers, the icy bodies and outer planets would have been tossed about and into each other, resulting in an ongoing cosmic dust storm. Any inner planets in the system would have burned up or been swallowed as their dying star expanded.

So far, the Helix nebula is one of only a few dead-star systems in which evidence for comet survivors has been found.

This image is made up of data from Spitzer's infrared array camera and multiband imaging photometer. Blue shows infrared light of 3.6 to 4.5 microns; green shows infrared light of 5.8 to 8 microns; and red shows infrared light of 24 microns.

A Spitzer Space Telescope Survey of Extreme Asymptotic Giant Branch Stars in M32

NASA Technical Reports Server (NTRS)

Jones, O.C.; McDonald, I.; Rich, R.M.; Kemper, F.; Boyer, M.L.; Zijlstra, A.A.; Bendo, G.J.

2014-01-01

We investigate the population of cool, evolved stars in the Local Group dwarf elliptical galaxy M32, using Infrared Array Camera observations from the Spitzer Space Telescope. We construct deep mid-infrared colour-magnitude diagrams for the resolved stellar populations within 3.5 arcminutes of M32's centre, and identify those stars that exhibit infrared excess. Our data is dominated by a population of luminous, dustproducing stars on the asymptotic giant branch (AGB) and extend to approximately 3 magnitudes below the AGB tip. We detect for the first time a sizeable population of 'extreme' AGB stars, highly enshrouded by circumstellar dust and likely completely obscured at optical wavelengths. The total dust-injection rate from the extreme AGB candidates is measured to be 7.5 x 10 (sup -7) solar masses per year, corresponding to a gas mass-loss rate of 1.5 x 10 (sup -4) solar masses per year. These extreme stars may be indicative of an extended star-formation epoch between 0.2 and 5 billion years ago.

Our Chaotic Neighbor

NASA Image and Video Library

2006-09-01

This vibrant image from NASA's Spitzer Space Telescope shows the Large Magellanic Cloud, a satellite galaxy to our own Milky Way galaxy. The infrared image, a mosaic of more than 100,000 individual tiles, offers astronomers a unique chance to study the lifecycle of stars and dust in a single galaxy. Nearly one million objects are revealed for the first time in this Spitzer view, which represents about a 1,000-fold improvement in sensitivity over previous space-based missions. Most of the new objects are dusty stars of various ages populating the Large Magellanic Cloud; the rest are thought to be background galaxies. The blue color in the picture, seen most prominently in the central bar, represents starlight from older stars. The chaotic, bright regions outside this bar are filled with hot, massive stars buried in thick blankets of dust. The red clouds contain cooler interstellar gas and molecular-sized dust grains illuminated by ambient starlight. The Large Magellanic Cloud, located 160,000 light-years from Earth, is one of a handful of dwarf galaxies that orbit our own Milky Way. It is approximately one-third as wide as the Milky Way, and, if it could be seen in its entirety, would cover the same amount of sky as a grid of about 480 full moons. About one-third of the whole galaxy can be seen in the Spitzer image. This picture is a composite of infrared light captured by Spitzer's infrared array camera. Light with wavelengths of 8 and 5.8 microns is red and orange: 4.5-micron light is green; and 3.6-micron light is blue. http://photojournal.jpl.nasa.gov/catalog/PIA07136

Discovery Of An Infrared Bow Shock Associated With Delta Cephei

NASA Astrophysics Data System (ADS)

Remage Evans, Nancy; Marengo, M.; Barmby, P.; Matthews, L. D.; Bono, G.; Welch, D. L.; Romaniello, M.; Huelsman, D.; Su, K. Y. L.; Fazio, G.

2010-05-01

We have obtained Spitzer Infrared Array Camera (IRAC) and Multiband Infrared Photometer for Spitzer (MIPS) observations of a sample of classical Cepheids both to derive infrared Leavitt Laws (Period-Luminosity Relations) and to look for evidence of mass loss in the spectral energy distributions. The MIPS 24 and 70 micron images of Delta Cep were particularly striking, since they show an arc of emission offset about an arcmin from Delta Cep. The emission is shaped like a bow shock and is aligned with the space motion of the Cepheid, implying it is physically related to the star. Bow shock structures of this kind can be formed when ram pressure of the ambient ISM balances the wind from a mass-losing star, raising the intriguing possibility that delta Cep is undergoing mass-loss during the Cepheid phase. Circumstellar emission is not a general feature of our Cepheid observations, but 2 unusual circumstances may make it visible around Delta Cep. If the Cepheid was already surrounded by interstellar matter, mass loss from the star could have created the bow shock. Second, Delta Cep has a physical companion 40" to the South, HD 213317, itself a binary. This B7-8 III-IV star is hot enough that it may produce infrared emission by heating dust within the ejected material. This work is based on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under NASA contract 1407. P. B. and D. W. both acknowledge research support through Discovery Grants from the Natural Sciences and Engineering Research Council of Canada. N. R. E. acknowledges support from the Chandra X-Ray Center grant NAS8-03060.

Dwarf Galaxies Swimming in Tidal Tails

NASA Technical Reports Server (NTRS)

2005-01-01

This false-color infrared image from NASA's Spitzer Space Telescope shows little 'dwarf galaxies' forming in the 'tails' of two larger galaxies that are colliding together. The big galaxies are at the center of the picture, while the dwarfs can be seen as red dots in the red streamers, or tidal tails. The two blue dots above the big galaxies are stars in the foreground.

Galaxy mergers are common occurrences in the universe; for example, our own Milky Way galaxy will eventually smash into the nearby Andromeda galaxy. When two galaxies meet, they tend to rip each other apart, leaving a trail, called a tidal tail, of gas and dust in their wake. It is out of this galactic debris that new dwarf galaxies are born.

The new Spitzer picture demonstrates that these particular dwarfs are actively forming stars. The red color indicates the presence of dust produced in star-forming regions, including organic molecules called polycyclic aromatic hydrocarbons. These carbon-containing molecules are also found on Earth, in car exhaust and on burnt toast, among other places. Here, the molecules are being heated up by the young stars, and, as a result, shine in infrared light.

This image was taken by the infrared array camera on Spitzer. It is a 4-color composite of infrared light, showing emissions from wavelengths of 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange), and 8.0 microns (red). Starlight has been subtracted from the orange and red channels in order to enhance the dust features.

'No Organics' Zone Circles Pinwheel

NASA Technical Reports Server (NTRS)

2008-01-01

The Pinwheel galaxy, otherwise known as Messier 101, sports bright reddish edges in this new infrared image from NASA's Spitzer Space Telescope. Research from Spitzer has revealed that this outer red zone lacks organic molecules present in the rest of the galaxy. The red and blue spots outside of the spiral galaxy are either foreground stars or more distant galaxies.

The organics, called polycyclic aromatic hydrocarbons, are dusty, carbon-containing molecules that help in the formation of stars. On Earth, they are found anywhere combustion reactions take place, such as barbeque pits and exhaust pipes. Scientists also believe this space dust has the potential to be converted into the stuff of life.

Spitzer found that the polycyclic aromatic hydrocarbons decrease in concentration toward the outer portion of the Pinwheel galaxy, then quickly drop off and are no longer detected at its very outer rim. According to astronomers, there's a threshold at the rim where the organic material is being destroyed by harsh radiation from stars. Radiation is more damaging at the far reaches of a galaxy because the stars there have less heavy metals, and metals dampen the radiation.

The findings help researchers understand how stars can form in these harsh environments, where polycyclic aromatic hydrocarbons are lacking. Under normal circumstances, the polycyclic aromatic hydrocarbons help cool down star-forming clouds, allowing them to collapse into stars. In regions like the rim of the Pinwheel as well as the very early universe stars form without the organic dust. Astronomers don't know precisely how this works, so the rim of the Pinwheel provides them with a laboratory for examining the process relatively close up.

In this image, infrared light with a wavelength of 3.6 microns is colored blue; 8-micron light is green; and 24-micron light is red. All three of Spitzer's instruments were used in the study: the infrared array camera, the multiband imaging photometer and the infrared spectrograph.

THE DROP DURING LESS THAN 300 DAYS OF A DUSTY WHITE DWARF'S INFRARED LUMINOSITY

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, S.; Jura, M., E-mail: sxu@astro.ucla.edu, E-mail: jura@astro.ucla.edu

2014-09-10

We report Spitzer/Infrared Array Camera photometry of WD J0959–0200, a white dwarf that displays excess infrared radiation from a disk, likely produced by a tidally disrupted planetesimal. We find that in 2010, the fluxes in both 3.6 μm and 4.5 μm decreased by ∼35% in less than 300 days. The drop in the infrared luminosity is likely due to an increase of the inner disk radius from one of two scenarios: (1) a recent planetesimal impact; (2) instability in the circumstellar disk. The current situation is tantalizing; high-sensitivity, high-cadence infrared studies will be a new tool to study the interplay between a diskmore » and its host white dwarf star.« less

Dissection of a Galaxy

NASA Technical Reports Server (NTRS)

2004-01-01

Sometimes, the best way to understand how something works is to take it apart. The same is true for galaxies like NGC 300, which NASA's Spitzer Space Telescope has divided into its various parts. NGC 300 is a face-on spiral galaxy located 7.5 million light-years away in the southern constellation Sculptor.

This false-color image taken by the infrared array camera on Spitzer readily distinguishes the main star component of the galaxy (blue) from its dusty spiral arms (red). The star distribution peaks strongly in the central bulge where older stars congregate, and tapers off along the arms where younger stars reside.

Thanks to Spitzer's unique ability to sense the heat or infrared emission from dust, astronomers can now clearly trace the embedded dust structures within NGC 300's arms. When viewed at visible wavelengths, the galaxy's dust appears as dark lanes, largely overwhelmed by bright starlight. With Spitzer, the dust - in particular organic compounds called polycyclic aromatic hydrocarbons - can be seen in vivid detail (red). These organic molecules are produced, along with heavy elements, by the stellar nurseries that pepper the arms.

The findings provide a better understanding of spiral galaxy mechanics and, in the future, will help decipher more distant galaxies, whose individual components cannot be resolved.

This image was taken on Nov. 21, 2003 and is composed of photographs obtained at four wavelengths: 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange) and 8 microns (red).

Stellar 'Incubators' Seen Cooking up Stars

NASA Technical Reports Server (NTRS)

2005-01-01

[figure removed for brevity, see original site] Figure 1

[figure removed for brevity, see original site] [figure removed for brevity, see original site] Figure 2Figure 3Figure 4Figure 5

This image composite compares visible-light and infrared views from NASA's Spitzer Space Telescope of the glowing Trifid Nebula, a giant star-forming cloud of gas and dust located 5,400 light-years away in the constellation Sagittarius.

Visible-light images of the Trifid taken with NASA's Hubble Space Telescope, Baltimore, Md. (inside left, figure 1) and the National Optical Astronomy Observatory, Tucson, Ariz., (outside left, figure 1) show a murky cloud lined with dark trails of dust. Data of this same region from the Institute for Radioastronomy millimeter telescope in Spain revealed four dense knots, or cores, of dust (outlined by yellow circles), which are 'incubators' for embryonic stars. Astronomers thought these cores were not yet ripe for stars, until Spitzer spotted the warmth of rapidly growing massive embryos tucked inside.

These embryos are indicated with arrows in the false-color Spitzer picture (right, figure 1), taken by the telescope's infrared array camera. The same embryos cannot be seen in the visible-light pictures (left, figure 1). Spitzer found clusters of embryos in two of the cores and only single embryos in the other two. This is one of the first times that multiple embryos have been observed in individual cores at this early stage of stellar development.

Dissection of a Galaxy

NASA Image and Video Library

2004-05-11

Sometimes, the best way to understand how something works is to take it apart. The same is true for galaxies like NGC 300, which NASA's Spitzer Space Telescope has divided into its various parts. NGC 300 is a face-on spiral galaxy located 7.5 million light-years away in the southern constellation Sculptor. This false-color image taken by the infrared array camera on Spitzer readily distinguishes the main star component of the galaxy (blue) from its dusty spiral arms (red). The star distribution peaks strongly in the central bulge where older stars congregate, and tapers off along the arms where younger stars reside. Thanks to Spitzer's unique ability to sense the heat or infrared emission from dust, astronomers can now clearly trace the embedded dust structures within NGC 300's arms. When viewed at visible wavelengths, the galaxy's dust appears as dark lanes, largely overwhelmed by bright starlight. With Spitzer, the dust - in particular organic compounds called polycyclic aromatic hydrocarbons - can be seen in vivid detail (red). These organic molecules are produced, along with heavy elements, by the stellar nurseries that pepper the arms. The findings provide a better understanding of spiral galaxy mechanics and, in the future, will help decipher more distant galaxies, whose individual components cannot be resolved. This image was taken on Nov. 21, 2003 and is composed of photographs obtained at four wavelengths: 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange) and 8 microns (red). http://photojournal.jpl.nasa.gov/catalog/PIA05879

CLOSE BINARIES WITH INFRARED EXCESS: DESTROYERS OF WORLDS?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matranga, M.; Drake, J. J.; Kashyap, V. L.

2010-09-10

We present the results of a Spitzer photometric investigation into the IR excesses of close binary systems. In a sample of 10 objects, excesses in Infrared Array Camera and MIPS24 bands implying the presence of warm dust are found for 3. For two objects, we do not find excesses reported in earlier IRAS studies. We discuss the results in the context of the scenario suggested by Rhee and co-workers, in which warm dust is continuously created by destructive collisions between planetary bodies. A simple numerical model for the steady-state distribution of dust in one IR excess system shows a centralmore » clearing of radius 0.22 AU caused by dynamical perturbations from the binary star. This is consistent with the size of the central clearing derived from the Spitzer spectral energy distribution. We conclude that close binaries could be efficient 'destroyers of worlds' and lead to destabilization of the orbits of their planetary progeny by magnetically driven angular momentum loss and secular shrinkage of the binary separation.« less

Constraining the atmosphere of exoplanet WASP-34b

NASA Astrophysics Data System (ADS)

Challener, Ryan; Harrington, Joseph; Cubillos, Patricio; Garland, Justin; Foster, Andrew S. D.; Blecic, Jasmina; Foster, Austin James; Smalley, Barry

2016-01-01

WASP-34b is a short-period exoplanet with a mass of 0.59 +/- 0.01 Jupiter masses orbiting a G5 star with a period of 4.3177 days and an eccentricity of 0.038 +/- 0.012 (Smalley, 2010). We observed WASP-34b using the 3.6 and 4.5 micron channels of the Infrared Array Camera aboard the Spitzer Space Telescope in 2010 (Program 60003). We applied our Photometry for Orbits, Eclipses, and Transits (POET) code to present eclipse-depth measurements, estimates of infrared brightness temperatures, and a refined orbit. With our Bayesian Atmospheric Radiative Transfer (BART) code, we characterized the atmosphere's temperature and pressure profile, and molecular abundances. Spitzer is operated by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. This work was supported by NASA Planetary Atmospheres grant NNX12AI69G and NASA Astrophysics Data Analysis Program grant NNX13AF38G. J. Blecic holds a NASA Earth and Space Science Fellowship.

Secondary eclipse observations and the atmosphere of exoplanet WASP-34b

NASA Astrophysics Data System (ADS)

Challener, Ryan C.; Harrington, Joseph; Cubillos, Patricio; Garland, Justin; Foster, Andrew S. D.; Blecic, Jasmina; Foster, AJ; Smalley, Barry

2015-11-01

WASP-34b is a short-period exoplanet with a mass of 0.59 ± 0.01 Jupiter masses orbiting a G5 star with a period of 4.3177 days and an eccentricity of 0.038 ± 0.012 (Smalley, 2010). We observed WASP-34b using the 3.6 and 4.5 μm channels of the Infrared Array Camera aboard the Spitzer Space Telescope in 2010 (Program 60003). We applied our Photometry for Orbits, Eclipses, and Transits (POET) code to present eclipse-depth measurements, estimates of infrared brightness temperatures, and a refined orbit. With our Bayesian Atmospheric Radiative Transfer (BART) code, we characterized the atmosphere's temperature and pressure profile, and molecular abundances. Spitzer is operated by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. This work was supported by NASA Planetary Atmospheres grant NNX12AI69G and NASA Astrophysics Data Analysis Program grant NNX13AF38G. J. Blecic holds a NASA Earth and Space Science Fellowship.

VizieR Online Data Catalog: The Auriga-California molecular cloud (Broekhoven-Fiene+, 2014)

NASA Astrophysics Data System (ADS)

Broekhoven-Fiene, H.; Matthews, B. C.; Harvey, P. M.; Gutermuth, R. A.; Huard, T. L.; Tothill, N. F. H.; Nutter, D.; Bourke, T. L.; Difrancesco, J.; Jorgensen, J. K.; Allen, L. E.; Chapman, N. L.; Cieza, L. A.; Dunham, M. M.; Merin, B.; Miller, J. F.; Terebey, S.; Peterson, D. E.; Stapelfeldt, K. R.

2017-06-01

We have mapped a significant fraction of the AMC with the Infrared Array Camera (IRAC; Fazio et al. 2004ApJS..154...10F) and the Mid-Infrared Photometer for Spitzer (MIPS; Rieke et al. 2004ApJS..154...25R) on board the Spitzer Space Telescope (Werner et al. 2004ApJS..154....1W), with a total overlapping coverage of 2.5 deg2 in the four IRAC bands (3.6, 4.5, 5.8 and 8.0 um) and 10.47 deg2 in the three MIPS bands (24, 70, and 160 um). The mapped areas are not all contiguous and were chosen to include the areas with AV>3, as given by the Dobashi et al. (2005PASJ...57....1S) extinction maps. The goal of these observations is to identify and characterize the young stellar object (YSO) and substellar object populations. The data presented here are the first mid-IR census of the YSO population in this region. (4 data files).

Spitzer Space Telescope Observations of Polars

NASA Astrophysics Data System (ADS)

Howell, S. B.; Brinkworth, C.; Chun, H.; Thomas, B.; Stefaniak, L.; Hoard, D. W.

2005-12-01

We have obtained the first Spitzer Space telescope observations of short orbital period polars. Using the Infrared Array Camera (IRAC), observations have been made in four broadband filters centered at 3.6, 4.5, 5.8, and 8.0 microns of the polars V347 Pav, GG Leo, RX J0154, and EF Eri. Spectral energy distributions have been produced for all four stars and in each case indicate excess emission in the longest wavebands. We examine our observations with respect to these binaries containing late M or brown dwarf type secondaries. We discuss the implications of the observed long wavelength emission excess in terms of the presence of dust and/or other possible emission mechanisms. The impact of this finding on the evolution of polars is also presented.

SPITZER IRAC OBSERVATIONS OF IR EXCESS IN HOLMBERG IX X-1: A CIRCUMBINARY DISK OR A VARIABLE JET?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dudik, R. P.; Berghea, C. T.; Roberts, T. P.

2016-11-01

We present Spitzer Infrared Array Camera photometric observations of the ultraluminous X-ray source (ULX, X-1) in Holmberg IX. We construct a spectral energy distribution (SED) for Holmberg IX X-1 based on published optical, UV, and X-ray data combined with the IR data from this analysis. We modeled the X-ray and optical data with disk and stellar models; however, we find a clear IR excess in the ULX SED that cannot be explained by fits or extrapolations of any of these models. Instead, further analysis suggests that the IR excess results from dust emission, possibly a circumbinary disk, or a variablemore » jet.« less

New SPIRITS discoveries of Infrared Transients and Variables

NASA Astrophysics Data System (ADS)

Jencson, J. E.; Kasliwal, M. M.; Adams, S.; Cook, D.; Tinyanont, S.; Kwan, S.; Prince, T.; Lau, R. M.; Perley, D.; Masci, F.; Helou, G.; Armus, L.; Surace, J.; Dyk, S. D. Van; Cody, A.; Boyer, M. L.; Bond, H. E.; Monson, A.; Bally, J.; Khan, R.; Levesque, E.; Fox, O.; Williams, R.; Whitelock, P. A.; Mohamed, S.; Gehrz, R. D.; Amodeo, S.; Shenoy, D.; Carlon, R.; Cass, A.; Corgan, D.; Dykhoff, D.; Faella, J.; Gburek, T.; Smith, N.; Cantiello, M.; Langer, N.; Ofek, E.; Johansson, J.; Parthasarathy, M.; Hsiao, E.; Phillips, M.; Morrell, N.; Gonzalez, C.; Contreras, C.

2017-10-01

We report the discoveries of mid-infrared transients/strong variables found in the course of the Spitzer InfraRed Intensive Transients Survey (SPIRITS) using Spitzer Early Release Data (ATel #6644, #7929, #8688, #8940, #9434, #10171, #10172, #10488).

A Spitzer Infrared Radius for the Transiting Extrasolar Planet HD 209458 b

NASA Technical Reports Server (NTRS)

Richardson, L. Jeremy; Harrington, Joseph; Seager, Sara; Deming, Drake

2007-01-01

We have measured the infrared transit of the extrasolar planet HD 209458 b using the Spitzer Space Telescope. We observed two primary eclipse events (one partial and one complete transit) using the 24 micrometer array of the Multiband Imaging Photometer for Spitzer (MIPS). We analyzed a total of 2392 individual images (10-second integrations) of the planetary system, recorded before, during, and after transit. We perform optimal photometry on the images and use the local zodiacal light as a short-term flux reference. At this long wavelength, the transit curve has a simple box-like shape, allowing robust solutions for the stellar and planetary radii independent of stellar limb darkening, which is negligible at 24 micrometers. We derive a stellar radius of R(sub *) = 1.06 plus or minus 0.07 solar radius, a planetary radius of R(sub p) = 1.26 plus or minus 0.08 R(sub J), and a stellar mass of 1.17 solar mass. Within the errors, our results agree with the measurements at visible wavelengths. The 24 micrometer radius of the planet therefore does not differ significantly compared to the visible result. We point out the potential for deriving extrasolar transiting planet radii to high accuracy using transit photometry at slightly shorter IR wavelengths where greater photometric precision is possible.

Star Formation in the DR21 Region A

NASA Image and Video Library

2004-04-13

Hidden behind a shroud of dust in the constellation Cygnus is a stellar nursery called DR21, which is giving birth to some of the most massive stars in our galaxy. Visible light images reveal no trace of this interstellar cauldron because of heavy dust obscuration. In fact, visible light is attenuated in DR21 by a factor of more than 10,000,000,000,000,000,000,000,000,000,000,000,000,000 (ten thousand trillion heptillion). New images from NASA's Spitzer Space Telescope allow us to peek behind the cosmic veil and pinpoint one of the most massive natal stars yet seen in our Milky Way galaxy. The never-before-seen star is 100,000 times as bright as the Sun. Also revealed for the first time is a powerful outflow of hot gas emanating from this star and bursting through a giant molecular cloud. The colorful image (top panel) is a large-scale composite mosaic assembled from data collected at a variety of different wavelengths. Views at visible wavelengths appear blue, near-infrared light is depicted as green, and mid-infrared data from the InfraRed Array Camera (IRAC) aboard NASA's Spitzer Space Telescope is portrayed as red. The result is a contrast between structures seen in visible light (blue) and those observed in the infrared (yellow and red). A quick glance shows that most of the action in this image is revealed to the unique eyes of Spitzer. The image covers an area about two times that of a full moon. Each of the constituent images is shown below the large mosaic. The Digital Sky Survey (DSS) image (lower left) provides a familiar view of deep space, with stars scattered around a dark field. The reddish hue is from gas heated by foreground stars in this region. This fluorescence fades away in the near-infrared Two-Micron All-Sky Survey (2MASS) image (lower center), but other features start to appear through the obscuring clouds of dust, now increasingly transparent. Many more stars are discerned in this image because near-infrared light pierces through some of the obscuration of the interstellar dust. Note that some stars seen as very bright in the visible image are muted in the near-infrared image, whereas other stars become more prominent. Embedded nebulae revealed in the Spitzer image are only hinted at in this picture. The Spitzer image (lower right) provides a vivid contrast to the other component images, revealing star-forming complexes and large-scale structures otherwise hidden from view. The Spitzer image is composed of photographs obtained at four wavelengths: 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange) and 8 microns (red). The brightest infrared cloud near the top center corresponds to DR21, which presumably contains a cluster of newly forming stars at a distance of nearly 10,000 light-years. The red filaments stretching across the Spitzer image denote the presence of polycyclic aromatic hydrocarbons. These organic molecules, comprised of carbon and hydrogen, are excited by surrounding interstellar radiation and become luminescent at wavelengths near 8 microns. The complex pattern of filaments is caused by an intricate combination of radiation pressure, gravity, and magnetic fields. The result is a tapestry in which winds, outflows, and turbulence move and shape the interstellar medium. http://photojournal.jpl.nasa.gov/catalog/PIA05735

Star Formation in the DR21 Region (A)

NASA Technical Reports Server (NTRS)

2004-01-01

[figure removed for brevity, see original site] Annotated mosaic

Hidden behind a shroud of dust in the constellation Cygnus is a stellar nursery called DR21, which is giving birth to some of the most massive stars in our galaxy. Visible light images reveal no trace of this interstellar cauldron because of heavy dust obscuration. In fact, visible light is attenuated in DR21 by a factor of more than 10,000,000,000,000,000,000,000,000,000,000,000,000,000 (ten thousand trillion heptillion).

New images from NASA's Spitzer Space Telescope allow us to peek behind the cosmic veil and pinpoint one of the most massive natal stars yet seen in our Milky Way galaxy. The never-before-seen star is 100,000 times as bright as the Sun. Also revealed for the first time is a powerful outflow of hot gas emanating from this star and bursting through a giant molecular cloud.

The colorful image (top panel) is a large-scale composite mosaic assembled from data collected at a variety of different wavelengths. Views at visible wavelengths appear blue, near-infrared light is depicted as green, and mid-infrared data from the InfraRed Array Camera (IRAC) aboard NASA's Spitzer Space Telescope is portrayed as red. The result is a contrast between structures seen in visible light (blue) and those observed in the infrared (yellow and red). A quick glance shows that most of the action in this image is revealed to the unique eyes of Spitzer. The image covers an area about two times that of a full moon.

Each of the constituent images is shown below the large mosaic. The Digital Sky Survey (DSS) image (lower left) provides a familiar view of deep space, with stars scattered around a dark field. The reddish hue is from gas heated by foreground stars in this region. This fluorescence fades away in the near-infrared Two-Micron All-Sky Survey (2MASS) image (lower center), but other features start to appear through the obscuring clouds of dust, now increasingly transparent. Many more stars are discerned in this image because near-infrared light pierces through some of the obscuration of the interstellar dust. Note that some stars seen as very bright in the visible image are muted in the near-infrared image, whereas other stars become more prominent. Embedded nebulae revealed in the Spitzer image are only hinted at in this picture.

The Spitzer image (lower right) provides a vivid contrast to the other component images, revealing star-forming complexes and large-scale structures otherwise hidden from view. The Spitzer image is composed of photographs obtained at four wavelengths: 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange) and 8 microns (red). The brightest infrared cloud near the top center corresponds to DR21, which presumably contains a cluster of newly forming stars at a distance of nearly 10,000 light-years.

The red filaments stretching across the Spitzer image denote the presence of polycyclic aromatic hydrocarbons. These organic molecules, comprised of carbon and hydrogen, are excited by surrounding interstellar radiation and become luminescent at wavelengths near 8 microns. The complex pattern of filaments is caused by an intricate combination of radiation pressure, gravity, and magnetic fields. The result is a tapestry in which winds, outflows, and turbulence move and shape the interstellar medium.

VizieR Online Data Catalog: YSO candidates in the Magellanic Bridge (Chen+, 2014)

NASA Astrophysics Data System (ADS)

Chen, C.-H. R.; Indebetouw, R.; Muller, E.; Kawamura, A.; Gordon, K. D.; Sewilo, M.; Whitney, B. A.; Fukui, Y.; Madden, S. C.; Meade, M. R.; Meixner, M.; Oliveira, J. M.; Robitaille, T. P.; Seale, J. P.; Shiao, B.; van Loon, J. Th.

2017-06-01

The Spitzer observations of the Bridge were obtained as part of the Legacy Program "Surveying the Agents of Galaxy Evolution in the Tidally-Stripped, Low-Metallicity Small Magellanic Cloud" (SAGE-SMC; Gordon et al. 2011AJ....142..102G). These observations included images taken at 3.6, 4.5, 5.8, and 8.0 um bands with the InfraRed Array Camera (IRAC) and at 24, 70, and 160 um bands with the Multiband Imaging Photometer for Spitzer (MIPS). The details of data processing are given in Gordon et al. (2011AJ....142..102G). To construct multi-wavelength SEDs for sources in the Spitzer catalog, we have expanded it by adding photometry from optical and NIR surveys covering the Bridge, i.e., BRI photometry from the Super COSMOS Sky Surveys (SSS; Hambly et al. 2001MNRAS.326.1279H) and JHKs photometry from the Two Micron All Sky Survey (2MASS; Skrutskie et al. 2006AJ....131.1163S, Cat. VII/233). (5 data files).

A Post-AGB Star in the Small Magellanic Cloud Observed with the Spitzer Infrared Spectrograph

DTIC Science & Technology

2006-10-23

spectral features, MSX SMC 029, in the Small Magellanic Cloud (SMC) usimg the low-resolution modules of the Infrared Spectrograph on the Spitzer Space ...029, in the Small Magellanic Cloud (SMC) using the low-resolution modules of the Infrared Spectrograph on the Spitzer Space Telescope. A cool dust... outer atmosphere expands and pulsates, pushing gas away from the star where it can cool and condense into dust grains. The resulting circumstellar dust

Spitzer Digs Up Hidden Stars

NASA Technical Reports Server (NTRS)

2007-01-01

[figure removed for brevity, see original site] 3-Panel Version Figure 1 [figure removed for brevity, see original site] [figure removed for brevity, see original site] [figure removed for brevity, see original site] Visible Light Figure 2 Infrared (IRAC) Figure 3 Combined Figure 4

Two rambunctious young stars are destroying their natal dust cloud with powerful jets of radiation, in an infrared image from NASA's Spitzer Space Telescope.

The stars are located approximately 600 light-years away in a cosmic cloud called BHR 71. In visible light (left panel), BHR 71 is just a large black structure. The burst of yellow light toward the bottom of the cloud is the only indication that stars might be forming inside. In infrared light (center panel), the baby stars are shown as the bright yellow smudges toward the center. Both of these yellow spots have wisps of green shooting out of them. The green wisps reveal the beginning of a jet. Like a rainbow, the jet begins as green, then transitions to orange, and red toward the end. The combined visible-light and infrared composite (right panel) shows that a young star's powerful jet is responsible for the rupture at the bottom of the dense cloud in the visible-light image. Astronomers know this because burst of light in the visible-light image overlaps exactly with a jet spouting-out of the left star, in the infrared image.

The jets' changing colors reveal a cooling effect, and may suggest that the young stars are spouting out radiation in regular bursts. The green tints at the beginning of the jet reveal really hot hydrogen gas, the orange shows warm gas, and the reddish wisps at the end represent the coolest gas. The fact that gas toward the beginning of the jet is hotter than gas near the middle suggests that the stars must give off regular bursts of energy -- and the material closest to the star is being heated by shockwaves from a recent stellar outburst. Meanwhile, the tints of orange reveal gas that is currently being heated by shockwaves from a previous stellar outburst. By the time these shockwaves reach the end of the jet, they have slowed down so significantly that the gas is only heated a little, and looks red. The combination of views also brings out some striking details that evaded visible-light detection. For example, the yellow dots scattered throughout the image are actually young stars forming inside BHR 71. Spitzer also uncovered another young star with jets, located to the right of the powerful jet seen in the visible-light image. Spitzer can see details that visible-light telescopes don't, because its infrared instruments are sensitive to 'heat.'

The infrared image is made up of data from Spitzer's infrared array camera. Blue shows infrared light at 3.6 microns, green is light at 4.5 microns, and red is light at 8.0 microns.

Rest-Frame Mid-Infrared Detection of an Extremely Luminous Lyman Break Galaxy with the Spitzer Infrared Spectrograph (IRS)

NASA Technical Reports Server (NTRS)

Teplitz, H. I.; Charmandaris, V.; Armus, L.; Appleton, P. N.; Houck, J. R.; Soifer, B. T.; Weedman, D.; Brandl, B. R.; vanCleve, J.; Grillmair, C.;

Fade to Red

NASA Technical Reports Server (NTRS)

2006-01-01

[figure removed for brevity, see original site] Infrared Andromeda Galaxy (M31) Poster [figure removed for brevity, see original site] [figure removed for brevity, see original site] Stars Dust

This animation shows the Andromeda galaxy, first as seen in visible light by the National Optical Astronomy Observatory, then as seen in infrared by NASA's Spitzer Space Telescope.

The visible-light image highlights the galaxy's population of about one trillion stars. The stars are so crammed into its core that this region blazes with bright starlight.

In contrast, the false-colored Spitzer view reveals red waves of dust against a more tranquil sea of blue stars. The dust lanes can be seen twirling all the way into the galaxy's center. This dust is warmed by young stars and shines at infrared wavelengths , which are represented in red. The blue color signifies shorter-wavelength infrared light primarily from older stars.

The Andromeda galaxy, also known affectionately by astronomers as Messier 31, is located 2.5 million light-years away in the constellation Andromeda. It is the closest major galaxy to the Milky Way, making it the ideal specimen for carefully examining the nature of galaxies. On a clear, dark night, the galaxy can be spotted with the naked eye as a fuzzy blob.

Andromeda's entire disk spans about 260,000 light-years, which means that a light beam would take 260,000 years to travel from one end of the galaxy to the other. By comparison, the Milky Way is about 100,000 light-years across. When viewed from Earth, Andromeda occupies a portion of the sky equivalent to seven full moons.

Because this galaxy is so large, the infrared images had to be stitched together out of about 3,000 separate Spitzer exposures. The light detected by Spitzer's infrared array camera at 3.6 and 4.5 microns is sensitive mostly to starlight and is shown in blue and green, respectively. The 8-micron light shows warm dust and is shown in red. The contribution from starlight has been subtracted from the 8-micron image to better highlight the dust structures.

Note: The size of the Full-Res TIFF for the still image is 14772 samples x 4953 lines.

Short-Wavelength Infrared Views of Messier 81

NASA Technical Reports Server (NTRS)

2003-01-01

The magnificent spiral arms of the nearby galaxy Messier 81 are highlighted in this NASA Spitzer Space Telescope image. Located in the northern constellation of Ursa Major (which also includes the Big Dipper), this galaxy is easily visible through binoculars or a small telescope. M81 is located at a distance of 12 million light-years from Earth.

Because of its proximity, M81 provides astronomers with an enticing opportunity to study the anatomy of a spiral galaxy in detail. The unprecedented spatial resolution and sensitivity of Spitzer at infrared wavelengths show a clear separation between the several key constituents of the galaxy: the old stars, the interstellar dust heated by star formation activity, and the embedded sites of massive star formation. The infrared images also permit quantitative measurements of the galaxy's overall dust content, as well as the rate at which new stars are being formed.

The infrared image was obtained by Spitzer's infrared array camera. It is a four-color composite of invisible light, showing emissions from wavelengths of 3.6 microns (blue), 4.5 microns (green), 5.8 microns (yellow) and 8.0 microns (red). Winding outward from the bluish-white central bulge of the galaxy, where old stars predominate and there is little dust, the grand spiral arms are dominated by infrared emission from dust. Dust in the galaxy is bathed by ultraviolet and visible light from the surrounding stars. Upon absorbing an ultraviolet or visible-light photon, a dust grain is heated and re-emits the energy at longer infrared wavelengths. The dust particles, composed of silicates (which are chemically similar to beach sand) and polycyclic aromatic hydrocarbons, trace the gas distribution in the galaxy. The well-mixed gas (which is best detected at radio wavelengths) and dust provide a reservoir of raw materials for future star formation.

The infrared-bright clumpy knots within the spiral arms denote where massive stars are being born in giant H II (ionized hydrogen) regions. The 8-micron emission traces the regions of active star formation in the galaxy. Studying the locations of these regions with respect to the overall mass distribution and other constituents of the galaxy (e.g., gas) will help identify the conditions and processes needed for star formation. With the Spitzer observations, this information comes to us without complications from absorption by cold dust in the galaxy, which makes interpretation of visible-light features uncertain.

The white stars scattered throughout the field of view are foreground stars within our own Milky Way galaxy.

High-resolution Interferometric Observations of Nova RS Ophiuchi and a Proposed Unification Model for Persistent Dust Creation in Recurrent Novae

NASA Astrophysics Data System (ADS)

Barry, R. K.; Danchi, W. C.

2008-12-01

We review observations of nova RS Ophiuchi using long-baseline near-infrared and mid-infrared interferometry at three observatories: the Keck Interferometer in the Nulling mode (KIN), the Palomar Testbed Interferometer (PTI), and the Infrared and Optical Telescope Array (IOTA). We discuss these observations in the context of a unifying model of the system that includes an increase in density in the plane of the orbit of the two stars created by a spiral shock wave caused by the motion of the stars through the cool wind of the red giant star. We discuss how recent observations using the Spitzer Space Telescope and the VLTI support this proposed model.

VizieR Online Data Catalog: WASP-31b:HST/Spitzer transmission spectral survey (Sing+, 2015)

NASA Astrophysics Data System (ADS)

Sing, D. K.; Wakeford, H. R.; Showman, A. P.; Nikolov, N.; Fortney, J. J.; Burrows, A. S.; Ballester, G. E.; Deming, D.; Aigrain, S.; Desert, J.-M.; Gibson, N. P.; Henry, G. W.; Knutson, H.; Lecavelier Des Etangs, A.; Pont, F.; Vidal-Madjar, A.; Williamson, M. W.; Wilson, P. A.

2017-11-01

We observed two transits of WASP-31b with the HST STIS G430L grating during 2012 June 13 and 26, as well as one transit with the STIS G750L during 2012 July 10. In addition to the STIS data, observations of WASP-31b were also conducted in the infrared with WFC3 on the HST. Observations began on 2012 May 13 at 12:53 using the IR G141 grism in forward spatial scan mode over five HST orbits. We analyse two transit observations obtained using the Infrared Array Camera (IRAC) instrument (Programme 90092 with P.I. Desert) on the Spitzer space telescope in the 3.6 μm and 4.5 μm channels in subarray mode (32x32 pixel, or 39 centred on the planets host). The 3.6 μm observation was performed on UT 2013 March 9 (between 06:59 and 11:37) and the 4.5 observation was performed on UT 2013 March 19 (between 12:19 and 16:58). (1 data file).

First Spitzer Space Telescope Observations of Magnetic Cataclysmic Variables: Evidence of Excess Emission at 3-8 μm

NASA Astrophysics Data System (ADS)

Howell, Steve B.; Brinkworth, Carolyn; Hoard, D. W.; Wachter, Stefanie; Harrison, Thomas; Chun, Howard; Thomas, Beth; Stefaniak, Linda; Ciardi, David R.; Szkody, Paula; van Belle, Gerard

2006-07-01

We present the first observations of magnetic cataclysmic variables using the Spitzer Space Telescope. We used the Infrared Array Camera to obtain photometry of the Polars EF Eri, GG Leo, V347 Pav, and RX J0154.0-5947 at 3.6, 4.5, 5.8, and 8.0 μm, respectively. In all of our targets, we detect excess mid-infrared emission over that expected from the component stars alone. We explore the origin of this IR excess by examining bremsstrahlung, cyclotron emission, circumbinary dust, and L/T brown dwarf secondary stars. Bremsstrahlung and cyclotron emission appear unlikely to be significant contributors to the observed fluxes. At present, the most likely candidate for the excess emission is dust that is probably located in a circumbinary disk with an inner temperature near 800 K. However, a simple dust disk plus any reasonable low-mass or brown dwarf-like secondary star is unable to fully explain the observed flux densities in the 3-8 μm region.

A Glimpse of the Milky Way

NASA Technical Reports Server (NTRS)

2005-01-01

[figure removed for brevity, see original site] Figure 1

In visible light, the bulk of our Milky Way galaxy's stars are eclipsed behind thick clouds of galactic dust and gas. But to the infrared eyes of NASA's Spitzer Space Telescope, distant stars and dust clouds shine with unparalleled clarity and color.

In this panoramic image (center row, fig. 1) from the Galactic Legacy Infrared Mid-Plane Survey Extraordinaire project, a plethora of stellar activity in the Milky Way's galactic plane, reaching to the far side of our galaxy, is exposed. This image spans 9 degrees of sky (approximately the width of a fist held out at arm's length).

The red clouds indicate the presence of large organic molecules (mixed with the dust), which have been illuminated by nearby star formation. The patches of black are dense obscuring dust clouds impenetrable by even Spitzer's super-sensitive infrared eyes. Bright arcs of white throughout the image are massive stellar incubators.

With over 160 megapixels, the full detail in this panorama cannot be appreciated without zooming in to various areas of interest (top and bottom rows, fig. 1). Bubbles, or holes, in the red clouds are formed by the powerful outflows from massive groups of forming stars. Wisps of green indicate the presence of hot hydrogen gas. Star clusters can also be seen as the groupings of blue, yellow, and green specks inside some of the red nebulae, or star-forming clouds.

In contrast to the plentiful examples of stellar youth in this montage, Spitzer also sees an object called a planetary nebula (top row, middle, fig. 1). Such nebulae are the final gasp of dying stars like our sun, whose outer layers are blown into space, leaving a burnt out core of a star, called a white dwarf, behind.

Although this panoramic image captures a large range of the galaxy, it represents only 7.5 percent of the primary Glimpse survey, which will image most of the star formation regions in our galaxy.

The infrared images were captured with the Spitzer's infrared array camera. The pictures are 4-channel false-color composites, showing emission from wavelengths of 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange), and 8.0 microns (red).

Caution: Images are best resolution available and are very large.

Is there a cluster in the massive star forming region IRAS 20126+4104?

NASA Astrophysics Data System (ADS)

Montes, V. A.; Hofner, Peter; Anderson, C.; Rosero, V.

2017-03-01

A Chandra X-ray Observatory ACIS-I observation and a 6 cm continuum radio observation with the Karl G. Jansky Very Large Array (VLA) together with a multiwavelength study in infrared (2MASS and Spitzer) and optical (USNO-B1.0) shows an increasing surface density of X-ray sources toward the massive protostar. There are at least 43 YSOs within 1.2 pc distance from the massive protostar. This number is consistent with typical B-type stars clusters (Lada & Lada 2003).

The Infrared Hunter

NASA Technical Reports Server (NTRS)

2006-01-01

[figure removed for brevity, see original site] [figure removed for brevity, see original site] Figure 1Figure 2

This image composite compares infrared and visible views of the famous Orion nebula and its surrounding cloud, an industrious star-making region located near the hunter constellation's sword. The infrared picture is from NASA's Spitzer Space Telescope, and the visible image is from the National Optical Astronomy Observatory, headquartered in Tucson, Ariz.

In addition to Orion, two other nebulas can be seen in both pictures. The Orion nebula, or M42, is the largest and takes up the lower half of the images; the small nebula to the upper left of Orion is called M43; and the medium-sized nebula at the top is NGC 1977. Each nebula is marked by a ring of dust that stands out in the infrared view. These rings make up the walls of cavities that are being excavated by radiation and winds from massive stars. The visible view of the nebulas shows gas heated by ultraviolet radiation from the massive stars.

Above the Orion nebula, where the massive stars have not yet ejected much of the obscuring dust, the visible image appears dark with only a faint glow. In contrast, the infrared view penetrates the dark lanes of dust, revealing bright swirling clouds and numerous developing stars that have shot out jets of gas (green). This is because infrared light can travel through dust, whereas visible light is stopped short by it.

The infrared image shows light captured by Spitzer's infrared array camera. Light with wavelengths of 8 and 5.8 microns (red and orange) comes mainly from dust that has been heated by starlight. Light of 4.5 microns (green) shows hot gas and dust; and light of 3.6 microns (blue) is from starlight.

Embedded Outflows from Herbig-Haro 46/47

NASA Technical Reports Server (NTRS)

2003-01-01

[figure removed for brevity, see original site] Click on image for larger view of insert

This image from NASA's Spitzer Space Telescope transforms a dark cloud into a silky translucent veil, revealing the molecular outflow from an otherwise hidden newborn star. Using near-infrared light, Spitzer pierces through the dark cloud to detect the embedded outflow in an object called HH 46/47. Herbig-Haro (HH) objects are bright, nebulous regions of gas and dust that are usually buried within dark clouds. They are formed when supersonic gas ejected from a forming protostar, or embryonic stars, interacts with the surrounding interstellar medium. These young stars are often detected only in the infrared.

The Spitzer image was obtained with the infrared array camera and is a three-color mosaic. Emission at 3.6 microns is shown as blue, emission from 4.5 and 5.8 microns has been combined as green, and 8.0 micron emission is depicted as red.

HH 46/47 is a striking example of a low mass protostar ejecting a jet and creating a bipolar, or two-sided, outflow. The central protostar lies inside a dark cloud (known as a 'Bok globule') which is illuminated by the nearby Gum Nebula. Located at a distance of 1,140 light-years and found in the constellation Vela, the protostar is hidden from view in the visible-light image (inset). With Spitzer, the star and its dazzling jets of molecular gas appear with clarity.

The 8-micron channel of the infrared array camera is sensitive to emission from polycyclic aromatic hydrocarbons. These organic molecules, comprised of carbon and hydrogen, are excited by the surrounding radiation field and become luminescent, accounting for the reddish cloud. Note that the boundary layer of the 8-micron emission corresponds to the lower right edge of the dark cloud in the visible-light picture.

Outflows are fascinating objects, since they characterize one of the most energetic phases of the formation of low-mass stars (like our Sun). The jets arising from these protostars can reach sizes of trillions of miles and velocities of hundreds of thousands miles per hour. Outflows are clear evidence of the presence of a process that creates supersonic beams of gas. This mechanism is tightly bound to the presence of circumstellar discs which surround the young stars. Such discs are likely to contain the materials from which planetary systems form. Our Sun probably underwent a similar process some 4.5 billion years ago. Hence the interest in understanding how quickly and efficiently this mass accretion and loss process takes place in protostars.

Ring Beholds a Delicate Flower

NASA Technical Reports Server (NTRS)

2005-01-01

NASA's Spitzer Space Telescope finds a delicate flower in the Ring Nebula, as shown in this image. The outer shell of this planetary nebula looks surprisingly similar to the delicate petals of a camellia blossom. A planetary nebula is a shell of material ejected from a dying star. Located about 2,000 light years from Earth in the constellation Lyra, the Ring Nebula is also known as Messier Object 57 and NGC 6720. It is one of the best examples of a planetary nebula and a favorite target of amateur astronomers.

The 'ring' is a thick cylinder of glowing gas and dust around the doomed star. As the star begins to run out of fuel, its core becomes smaller and hotter, boiling off its outer layers. The telescope's infrared array camera detected this material expelled from the withering star. Previous images of the Ring Nebula taken by visible-light telescopes usually showed just the inner glowing loop of gas around the star. The outer regions are especially prominent in this new image because Spitzer sees the infrared light from hydrogen molecules. The molecules emit infrared light because they have absorbed ultraviolet radiation from the star or have been heated by the wind from the star.

Download the QuickTime movie for the animated version of this Ring Nebula image.

VizieR Online Data Catalog: Spitzer observations of Taurus members (Luhman+, 2010)

NASA Astrophysics Data System (ADS)

Luhman, K. L.; Allen, P. R.; Espaillat, C.; Hartmann, L.; Calvet, N.

2016-03-01

For our census of the disk population in Taurus, we use images at 3.6, 4.5, 5.8, and 8.0um obtained with Spitzer's Infrared Array Camera (IRAC) and images at 24um obtained with the Multiband Imaging Photometer for Spitzer (MIPS). The cameras produced images with FWHM=1.6"-1.9" from 3.6 to 8.0um and FWHM=5.9" at 24um. The available data were obtained through Guaranteed Time Observations for PID = 6, 36, 37 (G. Fazio), 53 (G. Rieke), 94 (C. Lawrence), 30540 (G. Fazio, J. Houck), and 40302 (J. Houck), Director's Discretionary Time for PID = 462 (L. Rebull), Legacy programs for PID = 139, 173 (N. Evans), and 30816 (D. Padgett), and General Observer programs for PID = 3584 (D. Padgett), 20302 (P. Andre), 20386 (P. Myers), 20762 (J. Swift), 30384 (T. Bourke), 40844 (C. McCabe), and 50584 (D. Padgett). The IRAC and MIPS observations were performed through 180 and 137 Astronomical Observation Requests (AORs), respectively. The characteristics of the resulting images are summarized in Tables 1 and 2. (6 data files).

Spitzer Reveals Stellar 'Family Tree'

NASA Technical Reports Server (NTRS)

2008-01-01

[figure removed for brevity, see original site] High resolution poster version

Generations of stars can be seen in this new infrared portrait from NASA's Spitzer Space Telescope. In this wispy star-forming region, called W5, the oldest stars can be seen as blue dots in the centers of the two hollow cavities (other blue dots are background and foreground stars not associated with the region). Younger stars line the rims of the cavities, and some can be seen as dots at the tips of the elephant-trunk-like pillars. The white knotty areas are where the youngest stars are forming.

W5 spans an area of sky equivalent to four full moons and is about 6,500 light-years away in the constellation Cassiopeia. The Spitzer picture was taken over a period of 24 hours.

Like other massive star-forming regions, such as Orion and Carina, W5 contains large cavities that were carved out by radiation and winds from the region's most massive stars. According to the theory of triggered star-formation, the carving out of these cavities pushes gas together, causing it to ignite into successive generations of new stars.

This image contains some of the best evidence yet for the triggered star-formation theory. Scientists analyzing the photo have been able to show that the ages of the stars become progressively and systematically younger with distance from the center of the cavities.

This picture was taken with Spitzer's infrared array camera. It is a four-color composite, in which light with a wavelength of 3.6 microns is blue; 4.5-micron light is green; 5.8-micron light is orange; and 8-micron light is red.

The Anatomy of the Young Protostellar Outflow HH 211: Strong Evidence for CO v = 1-0 Fundamental Band Emission from Dense Gas in the Terminal Shock

NASA Astrophysics Data System (ADS)

Tappe, Achim; Forbrich, J.; Martín, S.; Lada, C. J.

2011-05-01

We present Spitzer Space Telescope 5-37 µm spectroscopic mapping observations toward the southeastern lobe of the young protostellar outflow HH 211 (part of IC 348 in Perseus, 260 pc). The terminal shock of the outflow shows a rich atomic and molecular spectrum with emission lines from OH, H2O, HCO+, CO2, H2, HD, [Fe II], [Si II], [Ne II], [S I], and [Cl I]. The spectrum also shows a rising continuum towards 5 µm, which we interpret as unresolved emission lines from highly excited rotational levels of the CO v=1-0 fundamental band. This interpretation is confirmed by a strong excess flux observed in the Spitzer IRAC 4-5 µm channel 2 image. We also observed the terminal outflow shock of this lobe with the Submillimeter Array (SMA) and detected pure rotational emission from CO 2-1, HCO+ 3-2, and HCN 3-2. The rotationally excited CO traces the collimated outflow and the terminal shock, whereas the vibrationally excited CO seen with Spitzer follows the continuation of the collimated outflow backbone in the terminal shock. The extremely high critical densities of the CO v=1-0 rovibrational lines indicate terminal shock jet densities larger than 107 cm-3. The unique combination of mid-infrared, submillimeter, and previous near-infrared observations allow us to gain detailed insights into the interaction of one of the youngest known protostellar outflows with its surrounding molecular cloud. Our results help to understand the nature of some of the so-called `green fuzzies’ (Extended Green Objects) identified by their Spitzer IRAC channel 2 excess and association with star-forming regions. They also provide a critical observational test to models of pulsed protostellar jets.

Spectrum from Embedded Star in Herbig-Haro 46/47

NASA Technical Reports Server (NTRS)

2003-01-01

NASA's Spitzer Space Telescope has lifted the cosmic veil to see an otherwise hidden newborn star, while detecting the presence of water and carbon dioxide ices, as well as organic molecules. Using near-infrared light, Spitzer pierces through an optically dark cloud to detect the embedded outflow in an object called HH 46/47. Herbig-Haro (HH) objects are bright, nebulous regions of gas and dust that are usually buried within dark dust clouds. They are formed when supersonic gas ejected from a forming protostar, or embryonic star, interacts with the surrounding interstellar medium. These young stars are often detected only in the infrared.

HH 46/47 is a striking example of a low mass protostar ejecting a jet and creating a bipolar, or two-sided, outflow. The central protostar lies inside a dark cloud (known as a 'Bok globule') which is illuminated by the nearby Gum Nebula. Located at a distance of 1140 light-years and found in the constellation Vela, the protostar is hidden from view in the visible-light image (inset). With Spitzer, the star and its dazzling jets of molecular gas appear with clarity.

The Spitzer image (inset) was obtained with the infrared array camera and is a three-color mosaic. Emission at 3.6 microns is shown as blue, emission from 4.5 and 5.8 microns has been combined as green, and 8.0 micron emission is depicted as red. The 8-micron channel of the camera is sensitive to emission from polycyclic aromatic hydrocarbons. These organic molecules, comprised of carbon and hydrogen, are excited by the surrounding radiation field and become luminescent, accounting for the reddish cloud. Note that the boundary layer of the 8-micron mission corresponds to the lower right edge of the dark cloud in the visible-light picture.

The primary image shows a spectrum obtained with Spitzer's infrared spectrograph instrument, stretching from wavelengths of 5.5 microns (left) to 20 microns (right). Spectra are graphical representations of a celestial object's unique blend of light. Characteristic patterns, or fingerprints, within the spectra allow astronomers to identify the object's chemical composition.

The broad depression in the center of the spectrum signifies the presence of silicates, which are chemically similar to beach sand. The depth of the silicate absorption feature indicates that the dusty cocoon surrounding the embedded protostar star is extremely thick Other absorption dips are produced by water ice (blue) and carbon dioxide ice (green). The fact that water and carbon dioxide appear in solid form suggests that the material immediately surrounding the protostar is cold. In addition, the Spitzer spectrum includes the chemical signatures of methane (purple) and methyl alcohol (tan).

Dayside atmospheric structure of HD209458b from Spitzer eclipses

NASA Astrophysics Data System (ADS)

Reinhard, Matthew; Harrington, Joseph; Challener, Ryan; Cubillos, Patricio; Blecic, Jasmina

2017-10-01

HD209458b is a hot Jupiter with a radius of 1.26 ± 0.08 Jupiter radii (Richardson et al, 2006) and a mass of 0.64 ± 0.09 Jupiter masses (Snellen et al, 2010). The planet orbits a G0 type star with an orbital period of 3.52472 ± 2.81699e-05 days, and a relatively low eccentricity of 0.0082 +0.0078/-0.0082 (Wang and Ford 2013). We report the analysis of observations of HD209458b during eclipse, taken in the 3.6 and 4.5 micron channels by the Spitzer Space Telescope's Infrared Array Camera (Program 90186). We produce a photometric light curve of the eclipses in both channels, using our Photometry for Orbits Eclipses and Transits (POET) code, and calculate the brightness temperatures and eclipse depths. We also present best estimates of the atmospheric parameters of HD209458b using our Bayesian Atmospheric Radiative Transfer (BART) code. These are some preliminary results of what will be an analysis of all available Spitzer data for HD209458b. Spitzer is operated by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. This work was supported by NASA Planetary Atmospheres grant NX12AI69G and NASA Astrophysics Data Analysis Program grant NNX13AF38G.

Pluto-Charon: Infrared Reflectance from 3.6 to 8.0 Micrometers

NASA Technical Reports Server (NTRS)

Cruikshank, Dale P.; Emery, Joshua P.; Stansberry, John A.; VanCleve, Jeffrey E.

2004-01-01

We have measured the spectral reflectance of the Pluto-Charon pair at 3.6, 4.5, 5.8, and 8.0 micrometers with the Infrared Array Camera (IRAC) (G. G. Fazzio et al. Ap.J.Supp. 154, 10-17, 2004) on the Spitzer Space Telescope (STS), at eight different longitudes that cover a full rotation of the planet. STS does not have sufficient resolution to separate the light from the planet and the satellite. The image of the Pluto-Charon pair is clearly visible at each of the four wavelengths. We will discuss the spectral reflectance in terms of models that include the known components of Pluto and Charon s surfaces, and evidence for diurnal variations.

Wanted: Galactic Thief Who Steals Gas

NASA Technical Reports Server (NTRS)

2007-01-01

[figure removed for brevity, see original site] Poster Version

A big galaxy is stealing gas right off the 'back' of its smaller companion in this new image from NASA's Spitzer Space Telescope. The stolen gas is hot, but it might eventually cool down to make new stars and planets.

The robber galaxy, called 3C 326 North, and its victim, 3C 326 South, are located about a billion light-years away from Earth in the Serpens constellation. They are both called radio galaxies, because the relativistic jets streaming out of their centers give off a great deal of radio waves. Other dots in the picture are foreground stars and background galaxies.

When astronomers first collected data on the 3C 326 galaxies with Spitzer's infrared spectrometer, they were surprised to find that 3C 326 North is loaded with an enormous amount of hot gas, called molecular hydrogen gas, which is fuel for stars and planets. They then studied this archived picture taken with Spitzer's infrared array camera and noticed a tail of stars connecting 3C 326 North to 3C 326 South. This tail revealed that the galactic pair are gravitationally tangled and might eventually merge --and that 3C 326 North must be hoisting gas from its smaller companion.

How is 3C 326 stealing the gas? The answer is gravity. The larger 3C 326 North, which is about the same mass as our Milky Way galaxy, has more gravity so the gas from 3C 326 South falls toward it in the same way that water rolls down hill on Earth. Even in space, it seems the bullies are bigger!

This image shows infrared light of three wavelengths: 8-micron light is red; 4.5 microns is green; 3.6 microns is blue.

DUST AROUND R CORONAE BOREALIS STARS. I. SPITZER/INFRARED SPECTROGRAPH OBSERVATIONS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anibal Garcia-Hernandez, D.; Kameswara Rao, N.; Lambert, David L., E-mail: agarcia@iac.es, E-mail: nkrao@iiap.res.in, E-mail: dll@astro.as.utexas.edu

2011-09-20

Spitzer/infrared spectrograph (IRS) spectra from 5 to 37 {mu}m for a complete sample of 31 R Coronae Borealis stars (RCBs) are presented. These spectra are combined with optical and near-infrared photometry of each RCB at maximum light to compile a spectral energy distribution (SED). The SEDs are fitted with blackbody flux distributions and estimates are made of the ratio of the infrared flux from circumstellar dust to the flux emitted by the star. Comparisons for 29 of the 31 stars are made with the Infrared Astronomical Satellite (IRAS) fluxes from three decades earlier: Spitzer and IRAS fluxes at 12 {mu}mmore » and 25 {mu}m are essentially equal for all but a minority of the sample. For this minority, the IRAS to Spitzer flux ratio exceeds a factor of three. The outliers are suggested to be stars where formation of a dust cloud or dust puff is a rare event. A single puff ejected prior to the IRAS observations may have been reobserved by Spitzer as a cooler puff at a greater distance from the RCB. RCBs which experience more frequent optical declines have, in general, a circumstellar environment containing puffs subtending a larger solid angle at the star and a quasi-constant infrared flux. Yet, the estimated subtended solid angles and the blackbody temperatures of the dust show a systematic evolution to lower solid angles and cooler temperatures in the interval between IRAS and Spitzer. Dust emission by these RCBs and those in the LMC is similar in terms of total 24 {mu}m luminosity and [8.0]-[24.0] color index.« less

A Shocking Surprise in Stephan's Quintet

NASA Technical Reports Server (NTRS)

2006-01-01

This false-color composite image of the Stephan's Quintet galaxy cluster clearly shows one of the largest shock waves ever seen (green arc). The wave was produced by one galaxy falling toward another at speeds of more than one million miles per hour. The image is made up of data from NASA's Spitzer Space Telescope and a ground-based telescope in Spain.

Four of the five galaxies in this picture are involved in a violent collision, which has already stripped most of the hydrogen gas from the interiors of the galaxies. The centers of the galaxies appear as bright yellow-pink knots inside a blue haze of stars, and the galaxy producing all the turmoil, NGC7318b, is the left of two small bright regions in the middle right of the image. One galaxy, the large spiral at the bottom left of the image, is a foreground object and is not associated with the cluster.

The titanic shock wave, larger than our own Milky Way galaxy, was detected by the ground-based telescope using visible-light wavelengths. It consists of hot hydrogen gas. As NGC7318b collides with gas spread throughout the cluster, atoms of hydrogen are heated in the shock wave, producing the green glow.

Spitzer pointed its infrared spectrograph at the peak of this shock wave (middle of green glow) to learn more about its inner workings. This instrument breaks light apart into its basic components. Data from the instrument are referred to as spectra and are displayed as curving lines that indicate the amount of light coming at each specific wavelength.

The Spitzer spectrum showed a strong infrared signature for incredibly turbulent gas made up of hydrogen molecules. This gas is caused when atoms of hydrogen rapidly pair-up to form molecules in the wake of the shock wave. Molecular hydrogen, unlike atomic hydrogen, gives off most of its energy through vibrations that emit in the infrared.

This highly disturbed gas is the most turbulent molecular hydrogen ever seen. Astronomers were surprised not only by the turbulence of the gas, but by the incredible strength of the emission. The reason the molecular hydrogen emission is so powerful is not yet completely understood.

Stephan's Quintet is located 300 million light-years away in the Pegasus constellation.

This image is composed of three data sets: near-infrared light (blue) and visible light called H-alpha (green) from the Calar Alto Observatory in Spain, operated by the Max Planck Institute in Germany; and 8-micron infrared light (red) from Spitzer's infrared array camera.

All Pillars Point to Eta

NASA Technical Reports Server (NTRS)

2005-01-01

[figure removed for brevity, see original site] [figure removed for brevity, see original site] Eta Carinae Starforming RegionSimulated Infrared View of Comet Tempel 1 (artist's concept)

These false-color image taken by NASA's Spitzer Space Telescope shows the 'South Pillar' region of the star-forming region called the Carina Nebula. Like cracking open a watermelon and finding its seeds, the infrared telescope 'busted open' this murky cloud to reveal star embryos (yellow or white) tucked inside finger-like pillars of thick dust (pink). Hot gases are green and foreground stars are blue. Not all of the newfound star embryos can be easily spotted.

Though the nebula's most famous and massive star, Eta Carinae, is too bright to be observed by infrared telescopes, the downward-streaming rays hint at its presence above the picture frame. Ultraviolet radiation and stellar winds from Eta Carinae and its siblings have shredded the cloud to pieces, leaving a mess of tendrils and pillars. This shredding process triggered the birth of the new stars uncovered by Spitzer.

The inset visible-light picture (figure 2) of the Carina Nebula shows quite a different view. Dust pillars are fewer and appear dark because the dust is soaking up visible light. Spitzer's infrared detectors cut through this dust, allowing it to see the heat from warm, embedded star embryos, as well as deeper, more buried pillars. The visible-light picture is from the National Optical Astronomy Observatory.

Eta Carina is a behemoth of a star, with more than 100 times the mass of our Sun. It is so massive that it can barely hold itself together. Over the years, it has brightened and faded as material has shot away from its surface. Some astronomers think Eta Carinae might die in a supernova blast within our lifetime.

Eta Carina's home, the Carina Nebula, is located in the southern portion of our Milky Way galaxy, 10,000 light-years from Earth. This colossal cloud of gas and dust stretches across 200 light-years of space. Though it is dominated by Eta Carinae, it also houses the star's slightly less massive siblings, in addition to the younger generations of stars.

This image was taken by the infrared array camera on Spitzer. It is a three-color composite of invisible light, showing emissions from wavelengths of 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange), and 8.0 microns (red).

The movie begins with a visible-light picture of the southern region of our Milky Way galaxy then slowly zooms into the area imaged by Spitzer.

The Anatomy of the Young Protostellar Outflow HH 211

NASA Astrophysics Data System (ADS)

Tappe, A.; Forbrich, J.; Martín, S.; Yuan, Y.; Lada, C. J.

2012-05-01

We present Spitzer Space Telescope 5-36 μm mapping observations toward the southeastern lobe of the young protostellar outflow HH 211. The southeastern terminal shock of the outflow shows a rich mid-infrared spectrum including molecular emission lines from OH, H2O, HCO+, CO2, H2, and HD. The spectrum also shows a rising infrared continuum toward 5 μm, which we interpret as unresolved emission lines from highly excited rotational levels of the CO v = 1-0 fundamental band. This interpretation is supported by a strong excess flux observed in the Spitzer/IRAC 4-5 μm channel 2 image compared to the other IRAC channels. The extremely high critical densities of the CO v = 1-0 ro-vibrational lines and a comparison to H2 and CO excitation models suggest jet densities larger than 106 cm-3 in the terminal shock. We also observed the southeastern terminal outflow shock with the Submillimeter Array and detected pure rotational emission from CO 2-1, HCO+ 3-2, and HCN 3-2. The rotationally excited CO traces the collimated outflow backbone as well as the terminal shock. HCN traces individual dense knots along the outflow and in the terminal shock, whereas HCO+ solely appears in the terminal shock. The unique combination of our mid-infrared and submillimeter observations with previously published near-infrared observations allow us to study the interaction of one of the youngest known protostellar outflows with its surrounding molecular cloud. Our results help us to understand the nature of some of the so-called green fuzzies (Extended Green Objects), and elucidate the physical conditions that cause high OH excitation and affect the chemical OH/H2O balance in protostellar outflows and young stellar objects. In an appendix to this paper, we summarize our Spitzer follow-up survey of protostellar outflow shocks to find further examples of highly excited OH occurring together with H2O and H2.

Ring of Stellar Death

NASA Technical Reports Server (NTRS)

2004-01-01

This false-color image from NASA's Spitzer Space Telescope shows a dying star (center) surrounded by a cloud of glowing gas and dust. Thanks to Spitzer's dust-piercing infrared eyes, the new image also highlights a never-before-seen feature -- a giant ring of material (red) slightly offset from the cloud's core. This clumpy ring consists of material that was expelled from the aging star.

The star and its cloud halo constitute a 'planetary nebula' called NGC 246. When a star like our own Sun begins to run out of fuel, its core shrinks and heats up, boiling off the star's outer layers. Leftover material shoots outward, expanding in shells around the star. This ejected material is then bombarded with ultraviolet light from the central star's fiery surface, producing huge, glowing clouds -- planetary nebulas -- that look like giant jellyfish in space.

In this image, the expelled gases appear green, and the ring of expelled material appears red. Astronomers believe the ring is likely made of hydrogen molecules that were ejected from the star in the form of atoms, then cooled to make hydrogen pairs. The new data will help explain how planetary nebulas take shape, and how they nourish future generations of stars.

This image composite was taken on Dec. 6, 2003, by Spitzer's infrared array camera, and is composed of images obtained at four wavelengths: 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange) and 8 microns (red).

Cosmic Infrared Background Fluctuations in Deep Spitzer Infrared Array Camera Images: Data Processing and Analysis

NASA Astrophysics Data System (ADS)

Arendt, Richard G.; Kashlinsky, A.; Moseley, S. H.; Mather, J.

2010-01-01

This paper provides a detailed description of the data reduction and analysis procedures that have been employed in our previous studies of spatial fluctuation of the cosmic infrared background (CIB) using deep Spitzer Infrared Array Camera observations. The self-calibration we apply removes a strong instrumental signal from the fluctuations that would otherwise corrupt the results. The procedures and results for masking bright sources and modeling faint sources down to levels set by the instrumental noise are presented. Various tests are performed to demonstrate that the resulting power spectra of these fields are not dominated by instrumental or procedural effects. These tests indicate that the large-scale (gsim30') fluctuations that remain in the deepest fields are not directly related to the galaxies that are bright enough to be individually detected. We provide the parameterization of these power spectra in terms of separate instrument noise, shot noise, and power-law components. We discuss the relationship between fluctuations measured at different wavelengths and depths, and the relations between constraints on the mean intensity of the CIB and its fluctuation spectrum. Consistent with growing evidence that the ~1-5 μm mean intensity of the CIB may not be as far above the integrated emission of resolved galaxies as has been reported in some analyses of DIRBE and IRTS observations, our measurements of spatial fluctuations of the CIB intensity indicate the mean emission from the objects producing the fluctuations is quite low (gsim1 nW m-2 sr-1 at 3-5 μm), and thus consistent with current γ-ray absorption constraints. The source of the fluctuations may be high-z Population III objects, or a more local component of very low luminosity objects with clustering properties that differ from the resolved galaxies. Finally, we discuss the prospects of the upcoming space-based surveys to directly measure the epochs inhabited by the populations producing these source-subtracted CIB fluctuations, and to isolate the individual fluxes of these populations.

HAT-P-16b: A Bayesian Atmospheric Retrieval

NASA Astrophysics Data System (ADS)

McIntyre, Kathleen; Harrington, Joseph; Blecic, Jasmina; Cubillos, Patricio; Challener, Ryan; Bakos, Gaspar

2017-10-01

HAT-P-16b is a hot (equilibrium temperature 1626 ± 40 K, assuming zero Bond albedo and efficient energy redistribution), 4.19 ± 0.09 Jupiter-mass exoplanet orbiting an F8 star every 2.775960 ± 0.000003 days (Buchhave et al 2010). We observed two secondary eclipses of HAT-P-16b using the 3.6 μm and 4.5 μm channels of the Spitzer Space Telescope's Infrared Array Camera (program ID 60003). We applied our Photometry for Orbits, Eclipses, and Transits (POET) code to produce normalized eclipse light curves, and our Bayesian Atmospheric Radiative Transfer (BART) code to constrain the temperature-pressure profiles and atmospheric molecular abundances of the planet. Spitzer is operated by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. This work was supported by NASA Planetary Atmospheres grant NNX12AI69G and NASA Astrophysics Data Analysis Program grant NNX13AF38G.

Infrared Astronomy and Education: Linking Infrared Whole Sky Mapping with Teacher and Student Research

NASA Astrophysics Data System (ADS)

Borders, Kareen; Mendez, Bryan; Thaller, Michelle; Gorjian, Varoujan; Borders, Kyla; Pitman, Peter; Pereira, Vincent; Sepulveda, Babs; Stark, Ron; Knisely, Cindy; Dandrea, Amy; Winglee, Robert; Plecki, Marge; Goebel, Jeri; Condit, Matt; Kelly, Susan

The Spitzer Space Telescope and the recently launched WISE (Wide Field Infrared Survey Explorer) observe the sky in infrared light. Among the objects WISE will study are asteroids, the coolest and dimmest stars, and the most luminous galaxies. Secondary students can do authentic research using infrared data. For example, students will use WISE data to mea-sure physical properties of asteroids. In order to prepare students and teachers at this level with a high level of rigor and scientific understanding, the WISE and the Spitzer Space Tele-scope Education programs provided an immersive teacher professional development workshop in infrared astronomy.The lessons learned from the Spitzer and WISE teacher and student pro-grams can be applied to other programs engaging them in authentic research experiences using data from space-borne observatories such as Herschel and Planck. Recently, WISE Educator Ambassadors and NASA Explorer School teachers developed and led an infrared astronomy workshop at Arecibo Observatory in PuertoRico. As many common misconceptions involve scale and distance, teachers worked with Moon/Earth scale, solar system scale, and distance and age of objects in the Universe. Teachers built and used basic telescopes, learned about the history of telescopes, explored ground and satellite based telescopes, and explored and worked on models of WISE Telescope. An in-depth explanation of WISE and the Spitzer telescopes gave participants background knowledge for infrared astronomy observations. We taught the electromagnetic spectrum through interactive stations. We will outline specific steps for sec-ondary astronomy professional development, detail student involvement in infrared telescope data analysis, provide data demonstrating the impact of the above professional development on educator understanding and classroom use, and detail future plans for additional secondary professional development and student involvement in infrared astronomy. Funding was provided by NASA, WISE Telescope, the Spitzer Space Telescope, the American Institute of Aeronautics and Astronautics, the National Optical Astronomy Observatory, Starbucks, and Washington Space Grant Consortium.

Where Galactic Snakes Live

NASA Image and Video Library

2006-10-27

This infrared image from NASA's Spitzer Space Telescope shows what astronomers are referring to as a "snake" (upper left) and its surrounding stormy environment. The sinuous object is actually the core of a thick, sooty cloud large enough to swallow dozens of solar systems. In fact, astronomers say the "snake's belly" may be harboring beastly stars in the process of forming. The galactic creepy crawler to the right of the snake is another thick cloud core, in which additional burgeoning massive stars might be lurking. The colorful regions below the two cloud cores are less dense cloud material, in which dust has been heated by starlight and glows with infrared light. Yellow and orange dots throughout the image are monstrous developing stars; the red star on the "belly" of the snake is 20 to 50 times as massive as our sun. The blue dots are foreground stars. The red ball at the bottom left is a "supernova remnant," the remains of massive star that died in a fiery blast. Astronomers speculate that radiation and winds from the star before it died, in addition to a shock wave created when it exploded, might have played a role in creating the snake. Spitzer was able to spot the two black cloud cores using its heat-seeking infrared vision. The objects are hiding in the dusty plane of our Milky Way galaxy, invisible to optical telescopes. Because their heat, or infrared light, can sneak through the dust, they first showed up in infrared images from past missions. The cloud cores are so thick with dust that if you were to somehow transport yourself into the middle of them, you would see nothing but black, not even a star in the sky. Now, that's spooky! Spitzer's view of the region provides the best look yet at the massive embryonic stars hiding inside the snake. Astronomers say these observations will ultimately help them better understand how massive stars form. By studying the clustering and range of masses of the stellar embryos, they hope to determine if the stars were born in the same way that our low-mass sun was formed - out of a collapsing cloud of gas and dust - or by another mechanism in which the environment plays a larger role. The snake is located about 11,000 light-years away in the constellation Sagittarius. This false-color image is a composite of infrared data taken by Spitzer's infrared array camera and multiband imaging photometer. Blue represents 3.6-micron light; green shows light of 8 microns; and red is 24-micron light. http://photojournal.jpl.nasa.gov/catalog/PIA01318

Where Galactic Snakes Live

NASA Technical Reports Server (NTRS)

2006-01-01

This infrared image from NASA's Spitzer Space Telescope shows what astronomers are referring to as a 'snake' (upper left) and its surrounding stormy environment. The sinuous object is actually the core of a thick, sooty cloud large enough to swallow dozens of solar systems. In fact, astronomers say the 'snake's belly' may be harboring beastly stars in the process of forming.

The galactic creepy crawler to the right of the snake is another thick cloud core, in which additional burgeoning massive stars might be lurking. The colorful regions below the two cloud cores are less dense cloud material, in which dust has been heated by starlight and glows with infrared light. Yellow and orange dots throughout the image are monstrous developing stars; the red star on the 'belly' of the snake is 20 to 50 times as massive as our sun. The blue dots are foreground stars.

The red ball at the bottom left is a 'supernova remnant,' the remains of massive star that died in a fiery blast. Astronomers speculate that radiation and winds from the star before it died, in addition to a shock wave created when it exploded, might have played a role in creating the snake.

Spitzer was able to spot the two black cloud cores using its heat-seeking infrared vision. The objects are hiding in the dusty plane of our Milky Way galaxy, invisible to optical telescopes. Because their heat, or infrared light, can sneak through the dust, they first showed up in infrared images from past missions. The cloud cores are so thick with dust that if you were to somehow transport yourself into the middle of them, you would see nothing but black, not even a star in the sky. Now, that's spooky!

Spitzer's new view of the region provides the best look yet at the massive embryonic stars hiding inside the snake. Astronomers say these observations will ultimately help them better understand how massive stars form. By studying the clustering and range of masses of the stellar embryos, they hope to determine if the stars were born in the same way that our low-mass sun was formed - out of a collapsing cloud of gas and dust - or by another mechanism in which the environment plays a larger role.

The snake is located about 11,000 light-years away in the constellation Sagittarius.

This false-color image is a composite of infrared data taken by Spitzer's infrared array camera and multiband imaging photometer. Blue represents 3.6-micron light; green shows light of 8 microns; and red is 24-micron light.

Identification of Luminous Infrared Galaxies at 1 <~ z <~ 2.51,2,3,4,

NASA Astrophysics Data System (ADS)

Le Floc'h, E.; Pérez-González, P. G.; Rieke, G. H.; Papovich, C.; Huang, J.-S.; Barmby, P.; Dole, H.; Egami, E.; Alonso-Herrero, A.; Wilson, G.; Miyazaki, S.; Rigby, J. R.; Bei, L.; Blaylock, M.; Engelbracht, C. W.; Fazio, G. G.; Frayer, D. T.; Gordon, K. D.; Hines, D. C.; Misselt, K. A.; Morrison, J. E.; Muzerolle, J.; Rieke, M. J.; Rigopoulou, D.; Su, K. Y. L.; Willner, S. P.; Young, E. T.

2004-09-01

We present preliminary results on 24 μm detections of luminous infrared galaxies at z>~1 with the Multiband Imaging Photometer for Spitzer (MIPS). Observations were performed in the Lockman Hole and the Extended Groth Strip (EGS) and were supplemented by data obtained with the Infrared Array Camera (IRAC) between 3 and 9 μm. The positional accuracy of <~2" for most MIPS/IRAC detections provides unambiguous identifications of their optical counterparts. Using spectroscopic redshifts from the Deep Extragalactic Evolutionary Probe survey, we identify 24 μm sources at z>~1 in the EGS, while the combination of the MIPS/IRAC observations with BVRIJHK ancillary data in the Lockman Hole also shows very clear cases of galaxies with photometric redshifts at 1<~z<~2.5. The observed 24 μm fluxes indicate infrared luminosities greater than 1011 Lsolar, while the data at shorter wavelengths reveal rather red and probably massive (M>~M*) galaxy counterparts. It is the first time that this population of luminous objects is detected up to z~2.5 in the infrared. Our work demonstrates the ability of the MIPS instrument to probe the dusty universe at very high redshift and illustrates how the forthcoming Spitzer deep surveys will offer a unique opportunity to illuminate a dark side of cosmic history not explored by previous infrared experiments. Based on observations collected at the German-Spanish Astronomical Center, Calar Alto, operated jointly by Max-Planck-Institut für Astronomie and Instituto de Astrofísica de Andalucia (CSIC). Based on observations made with the Isaac Newton Telescope, operated on the island of La Palma by the Isaac Newton Group in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias.

Spitzer SAGE-Spec: Near infrared spectroscopy, dust shells, and cool envelopes in extreme Large Magellanic Cloud asymptotic giant branch stars

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blum, R. D.; Srinivasan, S.; Kemper, F.

2014-11-01

K-band spectra are presented for a sample of 39 Spitzer Infrared Spectrograph (IRS) SAGE-Spec sources in the Large Magellanic Cloud. The spectra exhibit characteristics in very good agreement with their positions in the near-infrared—Spitzer color-magnitude diagrams and their properties as deduced from the Spitzer IRS spectra. Specifically, the near-infrared spectra show strong atomic and molecular features representative of oxygen-rich and carbon-rich asymptotic giant branch stars, respectively. A small subset of stars was chosen from the luminous and red extreme ''tip'' of the color-magnitude diagram. These objects have properties consistent with dusty envelopes but also cool, carbon-rich ''stellar'' cores. Modest amountsmore » of dust mass loss combine with the stellar spectral energy distribution to make these objects appear extreme in their near-infrared and mid-infrared colors. One object in our sample, HV 915, a known post-asymptotic giant branch star of the RV Tau type, exhibits CO 2.3 μm band head emission consistent with previous work that demonstrates that the object has a circumstellar disk.« less

NASA astronomical findings highlighted on This Week @NASA – January 8, 2016

NASA Image and Video Library

2016-01-08

New NASA astrophysics findings were highlighted at the 227th American Astronomical Society meeting, Jan. 4-8 in Kissimmee, Florida. The findings, which ranged from runaway stars to a burping galaxy, were made with the help of several NASA observation instruments, including the Spitzer Space Telescope, the Wide-field Infrared Survey Explorer, the Chandra X-ray Observatory, the Nuclear Spectroscopic Telescope Array and others. Also, Next space station crew preparing for mission, Economical new era of aviation, A new level of coral reef studies and more!

Education with Infrared Astronomy and Spitzer

NASA Astrophysics Data System (ADS)

Hemphill, Rosa; Blackwell, J. A.; Herrold, A.; Petroff, E.

2007-12-01

We present education and outreach results using our experiences involving the Spitzer Space Telescope project, Star Formation in High Redshift Clusters with Spitzer. The project is a collaboration between the Spitzer Science Center and the National Optical Astronomy Observatory. Using the Spitzer Space Telescope, we measured star formation rates in three galaxy clusters at intermediate redshifts. Six teachers were chosen for the program, each with an interest and involvement in astronomy education. From this project, lesson plans, public outreach, lectures and demonstrations were generated which better the understanding of infrared astronomy, multiwavelength astronomy, galaxy and star formation, and cosmology. The teacher mentors are Dr. Gregory Rudnick (NOAO), Dr. Rose Finn (Siena College), and Dr. Vandana Desai (Caltech). Please see the companion posters by Emily Petroff, Zak Schroeder, and Thomas Loughran, et al, for information concerning the science results.

VizieR Online Data Catalog: Candidate stellar bowshock nebulae from MIR (Kobulnicky+, 2016)

NASA Astrophysics Data System (ADS)

Kobulnicky, H. A.; Chick, W. T.; Schurhammer, D. P.; Andrews, J. E.; Povich, M. S.; Munari, S. A.; Olivier, G. M.; Sorber, R. L.; Wernke, H. N.; Dale, D. A.; Dixon, D. M.

2017-01-01

Our team conducted a visual examination of mid-infrared images from SST and the WISE to locate bowshock nebula candidates. The SST data included several wide-area surveys conducted using the Infrared Array Camera (IRAC) in its 3.6, 4.5, 5.8, and 8.0um bandpasses, along with 24um data from the Multiband Imaging Photometer for Spitzer (MIPS). The SST beam size at these bands is 1.66, 1.72, 1.88, 1.98, and 6" FWHM, respectively. The WISE data include images at the 3.4, 4.6, 12, and 22um bandpasses, which have beam sizes of 6.1, 6.4, 6.5, and 12" FWHM, respectively. (1 data file).

Dark Globule in IC 1396 (IRAC)

NASA Technical Reports Server (NTRS)

2003-01-01

[figure removed for brevity, see original site] Click on image for larger view of inset

NASA's Spitzer Space Telescope image of a glowing stellar nursery provides a spectacular contrast to the opaque cloud seen in visible light (inset). The Elephant's Trunk Nebula is an elongated dark globule within the emission nebula IC 1396 in the constellation of Cepheus. Located at a distance of 2,450 light-years, the globule is a condensation of dense gas that is barely surviving the strong ionizing radiation from a nearby massive star. The globule is being compressed by the surrounding ionized gas. The dark globule is seen in silhouette at visible-light wavelengths, backlit by the illumination of a bright star located to the left of the field of view.

The Spitzer Space Telescope pierces through the obscuration to reveal the birth of new protostars, or embryonic stars, and previously unseen young stars. The infrared image was obtained by Spitzer's infrared array camera. The image is a four-color composite of invisible light, showing emissions from wavelengths of 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange) and 8.0 microns (red). The filamentary appearance of the globule results from the sculpting effects of competing physical processes. The winds from a massive star, located to the left of the image, produce a dense circular rim comprising the 'head' of the globule and a swept-back tail of gas.

A pair of young stars (LkHa 349 and LkHa 349c) that formed from the dense gas has cleared a spherical cavity within the globule head. While one of these stars is significantly fainter than the other in the visible-light image, they are of comparable brightness in the infrared Spitzer image. This implies the presence of a thick and dusty disc around LkHa 349c. Such circumstellar discs are the precursors of planetary systems. They are much thicker in the early stages of stellar formation when the placental planet-forming material (gas and dust) is still present.

Examining the infrared variable star population discovered in the Small Magellanic Cloud using the SAGE-SMC survey

DOE Office of Scientific and Technical Information (OSTI.GOV)

Polsdofer, Elizabeth; Marengo, M.; Seale, J.

2015-02-01

We present our study on the infrared variability of point sources in the Small Magellanic Cloud (SMC). We use the data from the Spitzer Space Telescope Legacy Program “Surveying the Agents of Galaxy Evolution in the Tidally Stripped, Low Metallicity Small Magellanic Cloud” (SAGE-SMC) and the “Spitzer Survey of the Small Magellanic Cloud” (S{sup 3}MC) survey, over three different epochs, separated by several months to 3 years. Variability in the thermal infrared is identified using a combination of Spitzer’s InfraRed Array Camera 3.6, 4.5, 5.8, and 8.0 μm bands, and the Multiband Imaging Photometer for Spitzer 24 μm band. Anmore » error-weighted flux difference between each pair of three epochs (“variability index”) is used to assess the variability of each source. A visual source inspection is used to validate the photometry and image quality. Out of ∼2 million sources in the SAGE-SMC catalog, 814 meet our variability criteria. We matched the list of variable star candidates to the catalogs of SMC sources classified with other methods, available in the literature. Carbon-rich Asymptotic Giant Branch (AGB) stars make up the majority (61%) of our variable sources, with about a third of all of our sources being classified as extreme AGB stars. We find a small, but significant population of oxygen-rich (O-rich) AGB (8.6%), Red Supergiant (2.8%), and Red Giant Branch (<1%) stars. Other matches to the literature include Cepheid variable stars (8.6%), early type stars (2.8%), Young-stellar objects (5.8%), and background galaxies (1.2%). We found a candidate OH maser star, SSTISAGE1C J005212.88-730852.8, which is a variable O-rich AGB star, and would be the first OH/IR star in the SMC, if confirmed. We measured the infrared variability of a rare RV Tau variable (a post-AGB star) that has recently left the AGB phase. 59 variable stars from our list remain unclassified.« less

The star-forming cores in the centre of the Trifid nebula (M 20): from Herschel to the near-infrared

NASA Astrophysics Data System (ADS)

Tapia, M.; Persi, P.; Román-Zúñiga, C.; Elia, D.; Giovannelli, F.; Sabau-Graziati, L.

2018-04-01

A new detailed infrared (IR) study of eight star-forming dense condensations (TCs) in M 20, the Trifid nebula, is presented. The aim is to determine the physical properties of the dust in such globules and establish the presence and properties of their embedded protostellar and/or young stellar population. For this, we analysed new Herschel far-IR and Calar Alto near-IR images of the region, combined with Spitzer Infrared Array Camera (Spitzer/IRAC) archival observations. We confirm the presence of several young stellar objects (YSOs), most with mid-IR colours of Class II sources in all but one of the observed cores. Five TCs are dominated in the far-IR by Class I sources with bolometric luminosities between 100 and 500 L⊙. We report the discovery of a possible counterjet to HH 399 and its protostellar engine inside the photodissociation region TC2, as well as a bipolar outflow system, signposted by symmetric H2 emission knots, embedded in TC3. The present results are compatible with previous suggestions that star formation has been active in the region for some 3 × 105 yr, and that the most recent events in some of these TCs may have been triggered by the expansion of the H II region. We also obtained a revised value for the distance to M 20 of 2.0 ± 0.1 kpc.

Mission Concept for the Single Aperture Far-Infrared (SAFIR) Observatory

NASA Technical Reports Server (NTRS)

Benford, Dominic J.; Amato, Michael J.; Mather, John C.; Moseley, S. Harvey, Jr.

2004-01-01

We have developed a preliminary but comprehensive mission concept for SAFIR, as a 10 m-class far-infrared and submillimeter observatory that would begin development later in this decade to meet the needs outlined above. Its operating temperature (< or = 4K) and instrument complement would be optimized to reach the natural sky confusion limit in the far-infrared with diffraction-limited performance down to at least the atmospheric cutoff, lambda > or approx. 40 microns. This would provide a point source sensitivity improvement of several orders of magnitude over that of the Spitzer Space Telescope (previously SIRTF) or the Herschel Space Observatory. Additionally, it would have an angular resolution 12 times finer than that of Spitzer and three times finer than Herschel. This sensitivity and angular resolution are necessary to perform imaging and spectroscopic studies of individual galaxies in the early universe. We have considered many aspects of the SAFIR mission, including the telescope technology (optical design, materials, and packaging), detector needs and technologies, cooling method and required technology developments, attitude and pointing, power systems, launch vehicle, and mission operations. The most challenging requirements for this mission are operating temperature and aperture size of the telescope, and the development of detector arrays. SAFIR can take advantage of much of the technology under development for JWST, but with much less stringent requirements on optical accuracy.

Laser-Sharp Jet Splits Water

NASA Technical Reports Server (NTRS)

2008-01-01

A jet of gas firing out of a very young star can be seen ramming into a wall of material in this infrared image from NASA's Spitzer Space Telescope.

The young star, called HH 211-mm, is cloaked in dust and can't be seen. But streaming away from the star are bipolar jets, color-coded blue in this view. The pink blob at the end of the jet to the lower left shows where the jet is hitting a wall of material. The jet is hitting the wall so hard that shock waves are being generated, which causes ice to vaporize off dust grains. The shock waves are also heating material up, producing energetic ultraviolet radiation. The ultraviolet radiation then breaks the water vapor molecules apart.

The red color at the end of the lower jet represents shock-heated iron, sulfur and dust, while the blue color in both jets denotes shock-heated hydrogen molecules.

HH 211-mm is part of a cluster of about 300 stars, called IC 348, located 1,000 light-years away in the constellation Perseus.

This image is a composite of infrared data from Spitzer's infrared array camera and its multiband imaging photometer. Light with wavelengths of 3.6 and 4.5 microns is blue; 8-micron-light is green; and 24-micron light is red.

VizieR Online Data Catalog: Follow-up photometry of M101 OT2015-1 (Blagorodnova+, 2017)

NASA Astrophysics Data System (ADS)

Blagorodnova, N.; Kotak, R.; Polshaw, J.; Kasliwal, M. M.; Cao, Y.; Cody, A. M.; Doran, G. B.; Elias-Rosa, N.; Fraser, M.; Fremling, C.; Gonzalez-Fernandez, C.; Harmanen, J.; Jencson, J.; Kankare, E.; Kudritzki, R.-P.; Kulkarni, S. R.; Magnier, E.; Manulis, I.; Masci, F. J.; Mattila, S.; Nugent, P.; Ochner, P.; Pastorello, A.; Reynolds, T.; Smith, K.; Sollerman, J.; Taddia, F.; Terreran, G.; Tomasella, L.; Turatto, M.; Vreeswijk, P. M.; Wozniak, P.; Zaggia, S.

2017-07-01

The location of M101-OT2015-1 has been serendipitously imaged by numerous telescopes and instruments over the last 15 years (from 2000 to 2015). Our best quality pre-discovery image (seeing of 0.55") is an r-band exposure at -3625 days pre-peak from the Canada-France-Hawaii Telescope (CFHT). The historical optical data for M101-OT was retrieved from the CFHT MegaPrime and CFHT12K/Mosaic, using single and combined exposures, Pan-STARRS-1/GPC1 (PS1), Isaac Newton Telescope/Wide Field Camera (INT/WFC), and Sloan Digital Sky Survey (SDSS) DR 10 (Ahn+ 2014, see V/147). Unfortunately, there are no HST images covering the location of the source. Post-discovery optical magnitudes were obtained from the reported followup astronomer's telegrams (ATels), Liverpool Telescope (LT), the Nordic Optical Telescope (NOT), and the Palomar P48 and P60 telescopes. The infrared data were retrieved from CFHT/WIRCam, UKIRT/WFCAM, and the Spitzer Infrared Array Camera in 3.6 and 4.5um as part of the SPitzer InfraRed Intensive Transients Survey (SPIRITS) (Kasliwal+, 2017ApJ...839...88K). Details of pre-discovery photometry and post-discovery optical photometry may be found in the Appendices Tables 1 and 2, respectively. We obtained spectra of M101-OT using a range of facilities in 2015 Feb-Jul. (3 data files).

Galactic Dust Bunnies Found to Contain Carbon After All

NASA Technical Reports Server (NTRS)

2009-01-01

The 'Cat's Eye' nebula, or NGC 6543, is a well-studied example of a 'planetary nebula.' Such objects are the glowing remnants of dust and gas expelled from moderate-sized stars during their last stages of life. Our own sun will generate such a nebula in about five billion years.

NASA's Spitzer Space Telescope has studied many such planetary nebulae in infrared light, including a variety of more distant ones, which have helped scientists identify a population of carbon-bearing stars near our galaxy's center.

The infrared emission from the Cat's Eye is generated by a variety of elements and molecules. The bright inner region of this nebula shows a complex structure reminiscent of a feline eye. Outside this compact region lies a series of other structures representing material that was ejected slightly earlier in the central star's life, when it was a giant star.

The image is a composite of data from Spitzer's infrared array camera. Light with a wavelength of 3.6 microns is rendered as blue, 5.8 microns is displayed as green and 8.0 microns is represented in red. The brightness of the central area has been greatly reduced to make it possible to maintain its visibility while enhancing the brightness of the much fainter outer features. Overall colors have been enhanced to better show slight variations in hue.

Star Formation in Henize 206

NASA Image and Video Library

2004-03-08

This image from NASA Spitzer Space Telescope, shows the wispy filamentary structure of Henize 206, is a four-color composite mosaic created by combining data from an infrared array camera IRAC. The LMC is a small satellite galaxy gravitationally bound to our own Milky Way. Yet the gravitational effects are tearing the companion to shreds in a long-playing drama of 'intergalactic cannibalism.' These disruptions lead to a recurring cycle of star birth and star death. Astronomers are particularly interested in the LMC because its fractional content of heavy metals is two to five times lower than is seen in our solar neighborhood. [In this context, 'heavy elements' refer to those elements not present in the primordial universe. Such elements as carbon, oxygen and others are produced by nucleosynthesis and are ejected into the interstellar medium via mass loss by stars, including supernova explosions.] As such, the LMC provides a nearby cosmic laboratory that may resemble the distant universe in its chemical composition. The primary Spitzer image, showing the wispy filamentary structure of Henize 206, is a four-color composite mosaic created by combining data from an infrared array camera (IRAC) at near-infrared wavelengths and the mid-infrared data from a multiband imaging photometer (MIPS). Blue represents invisible infrared light at wavelengths of 3.6 and 4.5 microns. Note that most of the stars in the field of view radiate primarily at these short infrared wavelengths. Cyan denotes emission at 5.8 microns, green depicts the 8.0 micron light, and red is used to trace the thermal emission from dust at 24 microns. The separate instrument images are included as insets to the main composite. An inclined ring of emission dominates the central and upper regions of the image. This delineates a bubble of hot, x-ray emitting gas that was blown into space when a massive star died in a supernova explosion millions of years ago. The shock waves from that explosion impacted a cloud of nearby hydrogen gas, compressed it, and started a new generation of star formation. The death of one star led to the birth of many new stars. This is particularly evident in the MIPS inset, where the 24-micron emission peaks correspond to newly formed stars. The ultraviolet and visible-light photons from the new stars are absorbed by surrounding dust and re-radiated at longer infrared wavelengths, where it is detected by Spitzer. This emission nebula was cataloged by Karl Henize (HEN-eyes) while spending 1948-1951 in South Africa doing research for his Ph.D. dissertation at the University of Michigan. Henize later became a NASA astronaut and, at age 59, became the oldest rookie to fly on the Space Shuttle during an eight-day flight of the Challenger in 1985. He died just short of his 67th birthday in 1993 while attempting to climb the north face of Mount Everest, the world's highest peak. http://photojournal.jpl.nasa.gov/catalog/PIA05517

Central Stars of Mid-Infrared Nebulae Discovered with Spitzer and WISE

NASA Astrophysics Data System (ADS)

Gvaramadze, V. V.; Kniazev, A. Y.

2017-02-01

Searches for compact mid-IR nebulae with the Spitzer Space Telescope and the Wide-field Infrared Survey Explorer (WISE), accompanied by spectroscopic observations of central stars of these nebulae led to the discovery of many dozens of massive stars at different evolutionary stages, of which the most numerous are candidate luminous blue variables (LBVs). In this paper, we give a census of candidate and confirmed Galactic LBVs revealed with Spitzer and WISE, and present some new results of spectroscopic observations of central stars of mid-IR nebulae.

IDEOS: Fitting Infrared Spectra from Dusty Galaxies

NASA Astrophysics Data System (ADS)

Viola, Vincent; Rupke, D.

2014-01-01

We fit models to heavily obscured infrared spectra taken by the Spitzer Space Telescope and prepare them for cataloguing in the Infrared Database of Extragalactic Observables from Spitzer (IDEOS). When completed, IDEOS will contain homogeneously measured mid-infrared spectroscopic observables of more than 4200 galaxies beyond the Local Group. The software we use, QUESTFit, models the spectra using up to three extincted blackbodies (including silicate, water ice, and hydrocarbon absorption) and PAH templates. We present results from a sample of the approximately 200 heavily obscured spectra that will be present in IDEOS.

Infrared Luminosities and Dust Properties of z ≈ 2 Dust-obscured Galaxies

NASA Astrophysics Data System (ADS)

Bussmann, R. S.; Dey, Arjun; Borys, C.; Desai, V.; Jannuzi, B. T.; Le Floc'h, E.; Melbourne, J.; Sheth, K.; Soifer, B. T.

2009-11-01

We present SHARC-II 350 μm imaging of twelve 24 μm bright (F 24 μm > 0.8 mJy) Dust-Obscured Galaxies (DOGs) and Combined Array for Research in Millimeter-wave Astronomy (CARMA) 1 mm imaging of a subset of two DOGs. These objects are selected from the Boötes field of the NOAO Deep Wide-Field Survey. Detections of four DOGs at 350 μm imply infrared (IR) luminosities which are consistent to within a factor of 2 of expectations based on a warm-dust spectral energy distribution (SED) scaled to the observed 24 μm flux density. The 350 μm upper limits for the 8 non-detected DOGs are consistent with both Mrk 231 and M82 (warm-dust SEDs), but exclude cold dust (Arp 220) SEDs. The two DOGs targeted at 1 mm were not detected in our CARMA observations, placing strong constraints on the dust temperature: T dust > 35-60 K. Assuming these dust properties apply to the entire sample, we find dust masses of ≈3 × 108 M sun. In comparison to other dusty z ~ 2 galaxy populations such as submillimeter galaxies (SMGs) and other Spitzer-selected high-redshift sources, this sample of DOGs has higher IR luminosities (2 × 1013 L sun versus 6 × 1012 L sun for the other galaxy populations) that are driven by warmer dust temperatures (>35-60 K versus ~30 K) and lower inferred dust masses (3 × 108 M sun versus 3 × 109 M sun). Wide-field Herschel and Submillimeter Common-User Bolometer Array-2 surveys should be able to detect hundreds of these power-law-dominated DOGs. We use the existing Hubble Space Telescope and Spitzer/InfraRed Array Camera data to estimate stellar masses of these sources and find that the stellar to gas mass ratio may be higher in our 24 μm bright sample of DOGs than in SMGs and other Spitzer-selected sources. Although much larger sample sizes are needed to provide a definitive conclusion, the data are consistent with an evolutionary trend in which the formation of massive galaxies at z ~ 2 involves a submillimeter bright, cold-dust, and star-formation-dominated phase followed by a 24 μm bright, warm-dust and AGN-dominated phase.

Observatories Combine to Crack Open the Crab Nebula

NASA Image and Video Library

2017-12-08

Astronomers have produced a highly detailed image of the Crab Nebula, by combining data from telescopes spanning nearly the entire breadth of the electromagnetic spectrum, from radio waves seen by the Karl G. Jansky Very Large Array (VLA) to the powerful X-ray glow as seen by the orbiting Chandra X-ray Observatory. And, in between that range of wavelengths, the Hubble Space Telescope's crisp visible-light view, and the infrared perspective of the Spitzer Space Telescope. This video starts with a composite image of the Crab Nebula, a supernova remnant that was assembled by combining data from five telescopes spanning nearly the entire breadth of the electromagnetic spectrum: the Very Large Array, the Spitzer Space Telescope, the Hubble Space Telescope, the XMM-Newton Observatory, and the Chandra X-ray Observatory. The video dissolves to the red-colored radio-light view that shows how a neutron star’s fierce “wind” of charged particles from the central neutron star energized the nebula, causing it to emit the radio waves. The yellow-colored infrared image includes the glow of dust particles absorbing ultraviolet and visible light. The green-colored Hubble visible-light image offers a very sharp view of hot filamentary structures that permeate this nebula. The blue-colored ultraviolet image and the purple-colored X-ray image shows the effect of an energetic cloud of electrons driven by a rapidly rotating neutron star at the center of the nebula. Read more: go.nasa.gov/2r0s8VC Credits: NASA, ESA, J. DePasquale (STScI)

SPITZER SEARCH FOR DUST DISKS AROUND CENTRAL STARS OF PLANETARY NEBULAE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bilikova, Jana; Chu Youhua; Gruendl, Robert A.

2012-05-01

Two types of dust disks have been discovered around white dwarfs (WDs): small dust disks within the Roche limits of their WDs and large dust disks around hot WDs extending to radial distances of 10-10{sup 2} AU. The majority of the latter WDs are central stars of planetary nebulae (CSPNs). We have therefore used archival Spitzer Infrared Array Camera (IRAC) and Multiband Imaging Photometer for Spitzer (MIPS) observations of PNs to search for CSPNs with IR excesses and to make a comparative investigation of dust disks around stars at different evolutionary stages. We have examined available images of 72 resolvedmore » PNs in the Spitzer archive and found 56 of them large enough for the CSPN to be resolved from the PN. Among these, only 42 CSPNs are visible in IRAC and/or MIPS images and selected for photometric measurements. From the spectral energy distributions (SEDs) of these CSPNs, we find 19 cases with clear IR excess. Of these, seven are [WC]-type stars, two have apparent visual companions that account for the observed excess emission, two are symbiotic CSPNs, and in eight cases the IR excess originates from an extended emitter, likely a dust disk. For some of these CSPNs, we have acquired follow-up Spitzer MIPS images, Infrared Spectrograph spectra, and Gemini NIRI and Michelle spectroscopic observations. The SEDs and spectra show a great diversity in the emission characteristics of the IR excesses, which may imply different mechanisms responsible for the excess emission. For CSPNs whose IR excesses originate from dust continuum, the most likely dust production mechanisms are (1) breakup of bodies in planetesimal belts through collisions and (2) formation of circumstellar dust disks through binary interactions. A better understanding of post-asymptotic giant branch binary evolution as well as debris disk evolution along with its parent star is needed to distinguish between these different origins. Future observations to better establish the physical parameters of the dust disks and the presence of companions are needed for models to discern between the possible dust production mechanisms.« less

MAMBO observations at 240GHz of optically obscured Spitzer sources: source clumps and radio activity at high redshift

NASA Astrophysics Data System (ADS)

Andreani, P.; Magliocchetti, M.; de Zotti, G.

2010-01-01

Optically very faint (R > 25.5) sources detected by the Spitzer Space Telescope at 24μm represent a very interesting population at redshift z ~ (1.5-3). They exhibit strong clustering properties, implying that they are hosted by very massive haloes, and their mid-infrared emission could be powered by either dust-enshrouded star formation and/or by an obscured active galactic nucleus (AGN). We report observations carried out with the Max Planck Millimetre Bolometer (MAMBO) array at the IRAM 30-m antenna on Pico Veleta of a candidate protocluster with five optically obscured sources selected from the 24-μm Spitzer sample of the First-Look Survey. Interestingly, these sources appear to lie on a high-density filament aligned with the two radio jets of an AGN. Four out of five of the observed sources were detected. We combine these measurements with optical, infrared and radio observations to probe the nature of the candidate protocluster members. Our preliminary conclusions can be summarized as follows: the spectral energy distributions (SEDs) of all sources include both AGN and starburst contributions; the AGN contribution to the bolometric luminosities ranges between 14 and 26 per cent of the total. Such a contribution is enough for the AGN to dominate the emission at 5.8, 8 and 24μm, while the stellar component, inferred from SED fitting, prevails at 1.25mm and at λ < 4.5μm. The present analysis suggests a coherent interplay at high z between extended radio activity and the development of filamentary large-scale structures.

The Tarantula Nebula

NASA Technical Reports Server (NTRS)

2004-01-01

NASA's new Spitzer Space Telescope, formerly known as the Space Infrared Telescope Facility, has captured in stunning detail the spidery filaments and newborn stars of the Tarantula Nebula, a rich star-forming region also known as 30 Doradus. This cloud of glowing dust and gas is located in the Large Magellanic Cloud, the nearest galaxy to our own Milky Way, and is visible primarily from the Southern Hemisphere. This image of an interstellar cauldron provides a snapshot of the complex physical processes and chemistry that govern the birth - and death - of stars.

At the heart of the nebula is a compact cluster of stars, known as R136, which contains very massive and young stars. The brightest of these blue supergiant stars are up to 100 times more massive than the Sun, and are at least 100,000 times more luminous. These stars will live fast and die young, at least by astronomical standards, exhausting their nuclear fuel in a few million years.

The Spitzer Space Telescope image was obtained with an infrared array camera that is sensitive to invisible infrared light at wavelengths that are about ten times longer than visible light. In this four-color composite, emission at 3.6 microns is depicted in blue, 4.5 microns in green, 5.8 microns in orange, and 8.0 microns in red. The image covers a region that is three-quarters the size of the full moon.

The Spitzer observations penetrate the dust clouds throughout the Tarantula to reveal previously hidden sites of star formation. Within the luminescent nebula, many holes are also apparent. These voids are produced by highly energetic winds originating from the massive stars in the central star cluster. The structures at the edges of these voids are particularly interesting. Dense pillars of gas and dust, sculpted by the stellar radiation, denote the birthplace of future generations of stars.

The Spitzer image provides information about the composition of the material at the edges of the voids. The surface layers closest to the massive stars are subject to the most intense stellar radiation. Here, the atoms are stripped of their electrons, and the green color of these regions is indicative of the radiation from this highly excited, or 'ionized,' material. The ubiquitous red filaments seen throughout the image reveal the presence of molecular material thought to be rich in hydrocarbons.

The Tarantula Nebula is the nearest example of a 'starburst' phenomenon, in which intense episodes of star formation occur on massive scales. Most starbursts, however, are associated with dusty and distant galaxies. Spitzer infrared observations of the Tarantula provide astronomers with an unprecedented view of the lifecycle of massive stars and their vital role in regulating the birth of future stellar and planetary systems.

The Tarantula Nebula

NASA Image and Video Library

2004-01-13

NASA Spitzer Space Telescope, formerly known as the Space Infrared Telescope Facility, has captured in stunning detail the spidery filaments and newborn stars of theTarantula Nebula, a rich star-forming region also known as 30 Doradus. This cloud of glowing dust and gas is located in the Large Magellanic Cloud, the nearest galaxy to our own Milky Way, and is visible primarily from the Southern Hemisphere. This image of an interstellar cauldron provides a snapshot of the complex physical processes and chemistry that govern the birth - and death - of stars. At the heart of the nebula is a compact cluster of stars, known as R136, which contains very massive and young stars. The brightest of these blue supergiant stars are up to 100 times more massive than the Sun, and are at least 100,000 times more luminous. These stars will live fast and die young, at least by astronomical standards, exhausting their nuclear fuel in a few million years. The Spitzer Space Telescope image was obtained with an infrared array camera that is sensitive to invisible infrared light at wavelengths that are about ten times longer than visible light. In this four-color composite, emission at 3.6 microns is depicted in blue, 4.5 microns in green, 5.8 microns in orange, and 8.0 microns in red. The image covers a region that is three-quarters the size of the full moon. The Spitzer observations penetrate the dust clouds throughout the Tarantula to reveal previously hidden sites of star formation. Within the luminescent nebula, many holes are also apparent. These voids are produced by highly energetic winds originating from the massive stars in the central star cluster. The structures at the edges of these voids are particularly interesting. Dense pillars of gas and dust, sculpted by the stellar radiation, denote the birthplace of future generations of stars. The Spitzer image provides information about the composition of the material at the edges of the voids. The surface layers closest to the massive stars are subject to the most intense stellar radiation. Here, the atoms are stripped of their electrons, and the green color of these regions is indicative of the radiation from this highly excited, or 'ionized,' material. The ubiquitous red filaments seen throughout the image reveal the presence of molecular material thought to be rich in hydrocarbons. The Tarantula Nebula is the nearest example of a 'starburst' phenomenon, in which intense episodes of star formation occur on massive scales. Most starbursts, however, are associated with dusty and distant galaxies. Spitzer infrared observations of the Tarantula provide astronomers with an unprecedented view of the lifecycle of massive stars and their vital role in regulating the birth of future stellar and planetary systems. http://photojournal.jpl.nasa.gov/catalog/PIA05062

THE TYPE Ia SUPERNOVA RATE IN RADIO AND INFRARED GALAXIES FROM THE CANADA-FRANCE-HAWAII TELESCOPE SUPERNOVA LEGACY SURVEY

DOE Office of Scientific and Technical Information (OSTI.GOV)

Graham, M. L.; Pritchet, C. J.; Balam, D.

2010-02-15

We have combined the large SN Ia database of the Canada-France-Hawaii Telescope Supernova Legacy Survey and catalogs of galaxies with photometric redshifts, Very Large Array 1.4 GHz radio sources, and Spitzer infrared sources. We present eight SNe Ia in early-type host galaxies which have counterparts in the radio and infrared source catalogs. We find the SN Ia rate in subsets of radio and infrared early-type galaxies is {approx}1-5 times the rate in all early-type galaxies, and that any enhancement is always {approx}<2{sigma}. Rates in these subsets are consistent with predictions of the two-component 'A+B' SN Ia rate model. Since infraredmore » properties of radio SN Ia hosts indicate dust-obscured star formation, we incorporate infrared star formation rates into the 'A+B' model. We also show the properties of SNe Ia in radio and infrared galaxies suggest the hosts contain dust and support a continuum of delay time distributions (DTDs) for SNe Ia, although other DTDs cannot be ruled out based on our data.« less

Inner Milky Way Raging with Star Formation

NASA Technical Reports Server (NTRS)

2008-01-01

More than 444,580 frames from NASA's Spitzer Space Telescope were stitched together to create this portrait of the raging star-formation occurring in the inner Milky Way.

As inhabitants of a flat galactic disk, Earth and its solar system have an edge-on view of their host galaxy, like looking a glass dish from its edge. From our perspective, most of the galaxy is condensed into a blurry narrow band of light that stretches completely around the sky, also known as the galactic plane.

In this mosaic the galactic plane is broken up into five components: the far-left side of the plane (top image); the area just left of the galactic center (second to top); galactic center (middle); the area to the right of galactic center (second to bottom); and the far-right side of the plane (bottom). Together, these panels represent more than 50 percent of our entire Milky Way galaxy.

The red haze that permeates the picture comes from organic molecules called polycyclic aromatic hydrocarbons, which are illuminated by light from massive baby stars. On Earth, these molecules are found in automobile exhaust, or charred barbeque grills anywhere carbon molecules are burned incompletely.

The patches of black are dense, obscuring dust clouds impenetrable by even Spitzer's super-sensitive infrared eyes. Bright arcs of white throughout the image are massive stellar incubators. The bluish-white haze that hovers heavily in the middle panel is starlight from the older stellar population towards the center of the galaxy.

This picture was taken with Spitzer's infrared array camera, as part of the Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE) project. This is a four-color composite where blue is 3.6-micron light, green is 4.5 microns, orange is 5.8 microns and red is 8.0 microns.

Why Are Galaxies So Smooth?

NASA Image and Video Library

2009-04-30

This image from NASA's Spitzer Space Telescope shows the spiral galaxy NGC 2841, located about 46 million light-years from Earth in the constellation Ursa Major. The galaxy is helping astronomers solve one of the oldest puzzles in astronomy: Why do galaxies look so smooth, with stars sprinkled evenly throughout? An international team of astronomers has discovered that rivers of young stars flow from their hot, dense stellar nurseries, dispersing out to form large, smooth distributions. This image is a composite of three different wavelengths from Spitzer's infrared array camera. The shortest wavelengths are displayed inblue, and mostly show the older stars in NGC 2841, as well as foreground stars in our own Milky Way galaxy. The cooler areas are highlighted in red, and show the dusty, gaseous regions of the galaxy. Blue shows infrared light of 3.6 microns, green represents 4.5-micron light and red, 8.0-micron light. The contribution from starlight measured at 3.6 microns has been subtracted from the 8.0-micron data to enhance the visibility of the dust features.The shortest wavelengths are displayed inblue, and mostly show the older stars in NGC 2841, as well as foreground stars in our own Milky Way galaxy. http://photojournal.jpl.nasa.gov/catalog/PIA12001

Coronet: A Star-Formation Neighbor

NASA Image and Video Library

2007-09-13

This composite image shows the Coronet in X-rays from Chandra and infrared from NASA Spitzer Space Telescope orange, green, and cyan. The Spitzer data show young stars plus diffuse emission from dust.

A New Look at Stellar Outflows: Spitzer Observations of the HH 46/47 System

NASA Technical Reports Server (NTRS)

Noriega-Crespo, Alberto; Morris, Patrick; Marleau, Francine R.; Carey, Sean; Boogert, Adwin; van Dishoeck, Ewine; Evans, Neal J., II; Keene, Jocelyn; Muzerolle, James; Stapelfeldt, Karl;

Early 2017 observations of TRAPPIST-1 with Spitzer

NASA Astrophysics Data System (ADS)

Delrez, L.; Gillon, M.; Triaud, A. H. M. J.; Demory, B.-O.; de Wit, J.; Ingalls, J. G.; Agol, E.; Bolmont, E.; Burdanov, A.; Burgasser, A. J.; Carey, S. J.; Jehin, E.; Leconte, J.; Lederer, S.; Queloz, D.; Selsis, F.; Van Grootel, V.

2018-04-01

The recently detected TRAPPIST-1 planetary system, with its seven planets transiting a nearby ultracool dwarf star, offers the first opportunity to perform comparative exoplanetology of temperate Earth-sized worlds. To further advance our understanding of these planets' compositions, energy budgets, and dynamics, we are carrying out an intensive photometric monitoring campaign of their transits with the Spitzer Space Telescope. In this context, we present 60 new transits of the TRAPPIST-1 planets observed with Spitzer/Infrared Array Camera (IRAC) in 2017 February and March. We combine these observations with previously published Spitzer transit photometry and perform a global analysis of the resulting extensive data set. This analysis refines the transit parameters and provides revised values for the planets' physical parameters, notably their radii, using updated properties for the star. As part of our study, we also measure precise transit timings that will be used in a companion paper to refine the planets' masses and compositions using the transit timing variations method. TRAPPIST-1 shows a very low level of low-frequency variability in the IRAC 4.5-μm band, with a photometric RMS of only 0.11 per cent at a 123-s cadence. We do not detect any evidence of a (quasi-)periodic signal related to stellar rotation. We also analyse the transit light curves individually, to search for possible variations in the transit parameters of each planet due to stellar variability, and find that the Spitzer transits of the planets are mostly immune to the effects of stellar variations. These results are encouraging for forthcoming transmission spectroscopy observations of the TRAPPIST-1 planets with the James Webb Space Telescope.

Cosmic Infrared Background Fluctuations in Deep Spitzer Infrared Array Camera Images: Data Processing and Analysis

NASA Technical Reports Server (NTRS)

Arendt, Richard; Kashlinsky, A.; Moseley, S.; Mather, J.

2010-01-01

This paper provides a detailed description of the data reduction and analysis procedures that have been employed in our previous studies of spatial fluctuation of the cosmic infrared background (CIB) using deep Spitzer Infrared Array Camera observations. The self-calibration we apply removes a strong instrumental signal from the fluctuations that would otherwise corrupt the results. The procedures and results for masking bright sources and modeling faint sources down to levels set by the instrumental noise are presented. Various tests are performed to demonstrate that the resulting power spectra of these fields are not dominated by instrumental or procedural effects. These tests indicate that the large-scale ([greater, similar]30') fluctuations that remain in the deepest fields are not directly related to the galaxies that are bright enough to be individually detected. We provide the parameterization of these power spectra in terms of separate instrument noise, shot noise, and power-law components. We discuss the relationship between fluctuations measured at different wavelengths and depths, and the relations between constraints on the mean intensity of the CIB and its fluctuation spectrum. Consistent with growing evidence that the [approx]1-5 [mu]m mean intensity of the CIB may not be as far above the integrated emission of resolved galaxies as has been reported in some analyses of DIRBE and IRTS observations, our measurements of spatial fluctuations of the CIB intensity indicate the mean emission from the objects producing the fluctuations is quite low ([greater, similar]1 nW m-2 sr-1 at 3-5 [mu]m), and thus consistent with current [gamma]-ray absorption constraints. The source of the fluctuations may be high-z Population III objects, or a more local component of very low luminosity objects with clustering properties that differ from the resolved galaxies. Finally, we discuss the prospects of the upcoming space-based surveys to directly measure the epochs inhabited by the populations producing these source-subtracted CIB fluctuations, and to isolate the individual fluxes of these populations.

NASA Spitzer 12th Anniversary Space Calendar

NASA Image and Video Library

2015-08-20

NASA Spitzer Space Telescope celebrated its 12th anniversary with a new digital calendar showcasing some of the mission most notable discoveries and popular cosmic eye candy. The digital calendar is online at http://www.jpl.nasa.gov/images/spitzer/20150820/Spitzer12thAnniversaryCalendar.pdf The calendar follows the life of the mission, with each month highlighting top infrared images and discoveries from successive years -- everything from a dying star resembling the eye of a monster to a star-studded, swirling galaxy. The final month includes a brand new image of the glittery star-making factory known as the Monkey Head nebula. Spitzer, which launched into space on August 25, 2003, from Cape Canaveral, Florida, is still going strong. It continues to use its ultra-sensitive infrared vision to probe asteroids, comets, exoplanets (planets outside our solar system) and some of the farthest known galaxies. Recently, Spitzer helped discover the closest known rocky exoplanet to us, named HD219134b, at 21 light-years away. In fact, Spitzer's exoplanet studies continue to surprise the astronomy community. The telescope wasn't originally designed to study exoplanets, but as luck -- and some creative engineering -- would have it, Spitzer has turned out to be a critical tool in the field, probing the climates and compositions of these exotic worlds. This pioneering work began in 2005, when Spitzer became the first telescope to detect light from an exoplanet. http://photojournal.jpl.nasa.gov/catalog/PIA19872

Light from Red-Hot Planet

NASA Image and Video Library

2009-01-28

This figure charts 30 hours of observations taken by NASA Spitzer Space Telescope of a strongly irradiated exoplanet an planet orbiting a star beyond our own. Spitzer measured changes in the planet heat, or infrared light.

The Great Exoplanet Eclipse: Spitzer Observations of the Benchmark Sub-Saturn-Mass Planet KELT-11b

NASA Astrophysics Data System (ADS)

Colon, Knicole; Beatty, Thomas; Line, Michael; Kreidberg, Laura; Lopez, Eric; Stassun, Keivan; Rodriguez, Joseph; Pepper, Joshua; James, David

2017-10-01

KELT-11b is a unique sub-Saturn-mass planet with a super-Jupiter radius that is in orbit around a bright, metal-rich, sub-giant star. We propose to observe a single eclipse of KELT-11b with Spitzer in IRAC Channel 2, which will allow us to precisely constrain the orbital eccentricity of the planet, study atmospheric circulation in an as yet unexplored regime of planetary surface gravity and temperature, and perform comparative science with other exoplanets in order to explore the correlation between surface gravity and thermal structure. Spitzer is the only active facility capable of providing the high precision, continuous infrared eclipse photometry of KELT-11b that is required to reach these objectives. The Spitzer infrared eclipse combined with near-infrared transmission spectroscopy that we will obtain with WFC3 on the Hubble Space Telescope will ultimately enable a detailed investigation of the atmospheric properties of KELT-11b and will provide a benchmark for planning thermal observations of exoplanets with the James Webb Space Telescope.

Young Stars Emerge from Orion Head

NASA Image and Video Library

2007-05-17

This image from NASA's Spitzer Space Telescope shows infant stars "hatching" in the head of the hunter constellation, Orion. Astronomers suspect that shockwaves from a supernova explosion in Orion's head, nearly three million years ago, may have initiated this newfound birth. The region featured in this Spitzer image is called Barnard 30. It is located approximately 1,300 light-years away and sits on the right side of Orion's "head," just north of the massive star Lambda Orionis. Wisps of green in the cloud are organic molecules called polycyclic aromatic hydrocarbons. These molecules are formed anytime carbon-based materials are burned incompletely. On Earth, they can be found in the sooty exhaust from automobile and airplane engines. They also coat the grills where charcoal-broiled meats are cooked. Tints of orange-red in the cloud are dust particles warmed by the newly forming stars. The reddish-pink dots at the top of the cloud are very young stars embedded in a cocoon of cosmic gas and dust. Blue spots throughout the image are background Milky Way along this line of sight. This composite includes data from Spitzer's infrared array camera instrument, and multiband imaging photometer instrument. Light at 4.5 microns is shown as blue, 8.0 microns is green, and 24 microns is red. http://photojournal.jpl.nasa.gov/catalog/PIA09411

Young Stars Emerge from Orion's Head

NASA Technical Reports Server (NTRS)

2007-01-01

This image from NASA's Spitzer Space Telescope shows infant stars 'hatching' in the head of the hunter constellation, Orion. Astronomers suspect that shockwaves from a supernova explosion in Orion's head, nearly three million years ago, may have initiated this newfound birth

The region featured in this Spitzer image is called Barnard 30. It is located approximately 1,300 light-years away and sits on the right side of Orion's 'head,' just north of the massive star Lambda Orionis.

Wisps of green in the cloud are organic molecules called polycyclic aromatic hydrocarbons. These molecules are formed anytime carbon-based materials are burned incompletely. On Earth, they can be found in the sooty exhaust from automobile and airplane engines. They also coat the grills where charcoal-broiled meats are cooked.

Tints of orange-red in the cloud are dust particles warmed by the newly forming stars. The reddish-pink dots at the top of the cloud are very young stars embedded in a cocoon of cosmic gas and dust. Blue spots throughout the image are background Milky Way along this line of sight.

This composite includes data from Spitzer's infrared array camera instrument, and multiband imaging photometer instrument. Light at 4.5 microns is shown as blue, 8.0 microns is green, and 24 microns is red.

Comparison of BiLinearly Interpolated Subpixel Sensitivity Mapping and Pixel-Level Decorrelation

NASA Astrophysics Data System (ADS)

Challener, Ryan C.; Harrington, Joseph; Cubillos, Patricio; Foster, Andrew S.; Deming, Drake; WASP Consortium

2016-10-01

Exoplanet eclipse signals are weaker than the systematics present in the Spitzer Space Telescope's Infrared Array Camera (IRAC), and thus the correction method can significantly impact a measurement. BiLinearly Interpolated Subpixel Sensitivity (BLISS) mapping calculates the sensitivity of the detector on a subpixel grid and corrects the photometry for any sensitivity variations. Pixel-Level Decorrelation (PLD) removes the sensitivity variations by considering the relative intensities of the pixels around the source. We applied both methods to WASP-29b, a Saturn-sized planet with a mass of 0.24 ± 0.02 Jupiter masses and a radius of 0.84 ± 0.06 Jupiter radii, which we observed during eclipse twice with the 3.6 µm and once with the 4.5 µm channels of IRAC aboard Spitzer in 2010 and 2011 (programs 60003 and 70084, respectively). We compared the results of BLISS and PLD, and comment on each method's ability to remove time-correlated noise. WASP-29b exhibits a strong detection at 3.6 µm and no detection at 4.5 µm. Spitzer is operated by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. This work was supported by NASA Planetary Atmospheres grant NNX12AI69G and NASA Astrophysics Data Analysis Program grant NNX13AF38G.

New Views of a Familiar Beauty

NASA Image and Video Library

2005-01-12

This image composite compares the well-known visible-light picture of the glowing Trifid Nebula (left panel) with infrared views from NASA's Spitzer Space Telescope (remaining three panels). The Trifid Nebula is a giant star-forming cloud of gas and dust located 5,400 light-years away in the constellation Sagittarius. The false-color Spitzer images reveal a different side of the Trifid Nebula. Where dark lanes of dust are visible trisecting the nebula in the visible-light picture, bright regions of star-forming activity are seen in the Spitzer pictures. All together, Spitzer uncovered 30 massive embryonic stars and 120 smaller newborn stars throughout the Trifid Nebula, in both its dark lanes and luminous clouds. These stars are visible in all the Spitzer images, mainly as yellow or red spots. Embryonic stars are developing stars about to burst into existence. Ten of the 30 massive embryos discovered by Spitzer were found in four dark cores, or stellar "incubators," where stars are born. Astronomers using data from the Institute of Radioastronomy millimeter telescope in Spain had previously identified these cores but thought they were not quite ripe for stars. Spitzer's highly sensitive infrared eyes were able to penetrate all four cores to reveal rapidly growing embryos. http://photojournal.jpl.nasa.gov/catalog/PIA07225

On the Nature of Bright Infrared Sources in the Small Magellanic Cloud: Interpreting MSX through the Lens of Spitzer

NASA Astrophysics Data System (ADS)

Kraemer, Kathleen E.; Sloan, G. C.

2015-01-01

We compare infrared observations of the Small Magellanic Cloud (SMC) by the Midcourse Space Experiment (MSX) and the Spitzer Space Telescope to better understand what components of a metal-poor galaxy dominate radiative processes in the infrared. The SMC, at a distance of ~60 kpc and with a metallicity of ~0.1-0.2 solar, can serve as a nearby proxy for metal-poor galaxies at high redshift. The MSX Point Source Catalog contains 243 objects in the SMC that were detected at 8.3 microns, the most sensitive MSX band. Multi-epoch, multi-band mapping with Spitzer, supplemented with observations from the Two-Micron All-Sky Survey (2MASS) and the Wide-field Infrared Survey Explorer (WISE), provides variability information, and, together with spectra from Spitzer for ~15% of the sample, enables us to determine what these luminous sources are. How many remain simple point sources? What fraction break up into multiple stars? Which are star forming regions, with both bright diffuse emission and point sources? How do evolved stars and stellar remnants contribute at these wavelengths? What role do young stellar objects and HII regions play? Answering these questions sets the stage for understanding what we will see with the James Webb Space Telescope (JWST).

Life at the Intersection of Colliding Galaxies

NASA Image and Video Library

2004-09-07

This false-color image from NASA's Spitzer Space Telescope reveals hidden populations of newborn stars at the heart of the colliding "Antennae" galaxies. These two galaxies, known individually as NGC 4038 and 4039, are located around 68 million light-years away and have been merging together for about the last 800 million years. The latest Spitzer observations provide a snapshot of the tremendous burst of star formation triggered in the process of this collision, particularly at the site where the two galaxies overlap. The image was taken by Spitzer's infrared array camera and is a combination of infrared light ranging from 3.6 microns (shown in blue) to 8.0 microns (shown in red). The dust emission (red) is by far the strongest feature in this image. Starlight was systematically subtracted from the longer wavelength data (red) to enhance dust features. The two nuclei, or centers, of the merging galaxies show up as white areas, one above the other. The brightest clouds of forming stars lie in the overlap region between and left of the nuclei. Throughout the sky, astronomers have identified many of these so-called "interacting" galaxies, whose spiral discs have been stretched and distorted by their mutual gravity as they pass close to one another. The distances involved are so large that the interactions evolve on timescales comparable to geologic changes on Earth. Observations of such galaxies, combined with computer models of these collisions, show that the galaxies often become forever bound to one another, eventually merging into a single, spheroidal-shaped galaxy. Wavelengths of 3.6 microns are represented in blue, 4.5 microns in green and 5.8-8.0 microns in red. This image was taken on Dec. 24, 2003. http://photojournal.jpl.nasa.gov/catalog/PIA06853

What's Old is New in the Large Magellanic Cloud

NASA Technical Reports Server (NTRS)

2006-01-01

[figure removed for brevity, see original site] Poster Version Large Magellanic Cloud

This vibrant image from NASA's Spitzer Space Telescope shows the Large Magellanic Cloud, a satellite galaxy to our own Milky Way galaxy.

The infrared image, a mosaic of 300,000 individual tiles, offers astronomers a unique chance to study the lifecycle of stars and dust in a single galaxy. Nearly one million objects are revealed for the first time in this Spitzer view, which represents about a 1,000-fold improvement in sensitivity over previous space-based missions. Most of the new objects are dusty stars of various ages populating the Large Magellanic Cloud; the rest are thought to be background galaxies.

The blue color in the picture, seen most prominently in the central bar, represents starlight from older stars. The chaotic, bright regions outside this bar are filled with hot, massive stars buried in thick blankets of dust. The red color around these bright regions is from dust heated by stars, while the red dots scattered throughout the picture are either dusty, old stars or more distant galaxies. The greenish clouds contain cooler interstellar gas and molecular-sized dust grains illuminated by ambient starlight.

Astronomers say this image allows them to quantify the process by which space dust -- the same stuff that makes up planets and even people -- is recycled in a galaxy. The picture shows dust at its three main cosmic hangouts: around the young stars, where it is being consumed (red-tinted, bright clouds); scattered about in the space between stars (greenish clouds); and in expelled shells of material from old stars (randomly-spaced red dots).

The Large Magellanic Cloud, located 160,000 light-years from Earth, is one of a handful of dwarf galaxies that orbit our own Milky Way. It is approximately one-third as wide as the Milky Way, and, if it could be seen in its entirety, would cover the same amount of sky as a grid of about 480 full moons. About one-third of the entire galaxy can be seen in the Spitzer image.

This picture is a composite of infrared light captured by Spitzer. Light with wavelengths of 3.6 (blue) and 8 (green) microns was captured by the telescope's infrared array camera; 24-micron light (red) was detected by the multiband imaging photometer.

What Old is New in the Large Magellanic Cloud

NASA Image and Video Library

2006-09-01

This vibrant image from NASA's Spitzer Space Telescope shows the Large Magellanic Cloud, a satellite galaxy to our own Milky Way galaxy. The infrared image, a mosaic of 300,000 individual tiles, offers astronomers a unique chance to study the lifecycle of stars and dust in a single galaxy. Nearly one million objects are revealed for the first time in this Spitzer view, which represents about a 1,000-fold improvement in sensitivity over previous space-based missions. Most of the new objects are dusty stars of various ages populating the Large Magellanic Cloud; the rest are thought to be background galaxies. The blue color in the picture, seen most prominently in the central bar, represents starlight from older stars. The chaotic, bright regions outside this bar are filled with hot, massive stars buried in thick blankets of dust. The red color around these bright regions is from dust heated by stars, while the red dots scattered throughout the picture are either dusty, old stars or more distant galaxies. The greenish clouds contain cooler interstellar gas and molecular-sized dust grains illuminated by ambient starlight. Astronomers say this image allows them to quantify the process by which space dust -- the same stuff that makes up planets and even people -- is recycled in a galaxy. The picture shows dust at its three main cosmic hangouts: around the young stars, where it is being consumed (red-tinted, bright clouds); scattered about in the space between stars (greenish clouds); and in expelled shells of material from old stars (randomly-spaced red dots). The Large Magellanic Cloud, located 160,000 light-years from Earth, is one of a handful of dwarf galaxies that orbit our own Milky Way. It is approximately one-third as wide as the Milky Way, and, if it could be seen in its entirety, would cover the same amount of sky as a grid of about 480 full moons. About one-third of the entire galaxy can be seen in the Spitzer image. This picture is a composite of infrared light captured by Spitzer. Light with wavelengths of 3.6 (blue) and 8 (green) microns was captured by the telescope's infrared array camera; 24-micron light (red) was detected by the multiband imaging photometer. http://photojournal.jpl.nasa.gov/catalog/PIA07137

Lighting up a Dead Star Layers

NASA Image and Video Library

2006-10-26

This image from NASA Spitzer Space Telescope shows the scattered remains of an exploded star named Cassiopeia A. Spitzer infrared detectors picked through these remains and found that much of the star original layering had been preserved.

SEDS: The Spitzer Extended Deep Survey. Survey Design, Photometry, and Deep IRAC Source Counts

NASA Technical Reports Server (NTRS)

Ashby, M. L. N.; Willner, S. P.; Fazio, G. G.; Huang, J.-S.; Arendt, A.; Barmby, P.; Barro, G; Bell, E. F.; Bouwens, R.; Cattaneo, A.;

Spitzer Photometry of WISE-Selected Brown Dwarf and Hyper-Lumninous Infrared Galaxy Candidates

NASA Technical Reports Server (NTRS)

Griffith, Roger L.; Kirkpatrick, J. Davy; Eisenhardt, Peter R. M.; Gelino, Christopher R.; Cushing, Michael C.; Benford, Dominic; Blain, Andrew; Bridge, Carrie R.; Cohen, Martin; Cutri, Roc M.;

SPIRITS: SPitzer InfraRed Intensive Transients Survey

NASA Astrophysics Data System (ADS)

Kasliwal, Mansi; Lau, Ryan; Cao, Yi; Masci, Frank; Helou, George; Williams, Robert; Bally, John; Bond, Howard; Whitelock, Patricia; Cody, Ann Marie; Gehrz, Robert; Jencson, Jacob; Tinyanont, Samaporn; Smith, Nathan; Surace, Jason; Armus, Lee; Cantiello, Matteo; Langer, Norbert; Levesque, Emily; Mohamed, Shazrene; Ofek, Eran; Parthasarathy, Mudumba; van Dyk, Schuyler; Boyer, Martha; Phillips, Mark; Hsiao, Eric; Morrell, Nidia; Perley, Dan; Gonzalez, Consuelo; Contreras, Carlos; Jones, Olivia; Ressler, Michael; Adams, Scott; Moore, Anna; Cook, David; Fox, Ori; Johansson, Joel; Khan, Rubab; Monson, Andy

2016-08-01

Spitzer is pioneering a systematic exploration of the dynamic infrared sky. Our SPitzer InfraRed Intensive Transients Survey (SPIRITS) has already discovered 147 explosive transients and 1948 eruptive variables. Of these 147 infrared transients, 35 are so red that they are devoid of optical counterparts and we call them SPRITEs (eSPecially Red Intermediate-luminosity Transient Events). The nature of SPRITEs is unknown and progress on deciphering the explosion physics depends on mid-IR spectroscopy. Multiple physical origins have been proposed including stellar merger, birth of a massive binary, electron capture supernova and stellar black-hole formation. Hence, we propose a modest continuation of SPIRITS, focusing on discovering and monitoring SPRITEs, in preparation for follow-up with the James Webb Space Telescope (JWST). As the SPRITEs evolve and cool, the bulk of the emission shifts to longer wavelengths. MIRI aboard JWST will be the only available platform in the near future capable of characterizing SPRITEs out to 28um. Specifically, the low resolution spectrometer would determine dust mass, grain chemistry, ice abundance and energetics to disentangle the proposed origins. The re-focused SPIRITS program consists of continued Spitzer monitoring of only those 104 luminous galaxies that are known SPRITE hosts or are most likely to host new SPRITEa. Scaling from the SPIRITS discovery rate, we estimate finding 22 new SPRITEs and 6 new supernovae over the next two years. The SPIRITS team remains committed to extensive ground-based follow-up. The Spitzer observations proposed here are essential for determining the final fates of active SPRITEs as well as bridging the time lag between the current SPIRITS survey and JWST launch.

SPIRITS: SPitzer InfraRed Intensive Transients Survey

NASA Astrophysics Data System (ADS)

Kasliwal, Mansi; Jencson, Jacob; Lau, Ryan; Masci, Frank; Helou, George; Williams, Robert; Bally, John; Bond, Howard; Whitelock, Patricia; Cody, Ann Marie; Gehrz, Robert; Tinyanont, Samaporn; Smith, Nathan; Surace, Jason; Armus, Lee; Cantiello, Matteo; Langer, Norbert; Levesque, Emily; Mohamed, Shazrene; Ofek, Eran; Parthasarathy, Mudumba; van Dyk, Schuyler; Boyer, Martha; Phillips, Mark; Hsiao, Eric; Morrell, Nidia; Perley, Dan; Gonzalez, Consuelo; Contreras, Carlos; Jones, Olivia; Ressler, Michael; Adams, Scott; Moore, Anna; Cook, David; Fox, Ori; Johansson, Joel; Khan, Rubab; Monson, Andrew; Hankins, Matthew; Goldman, Steven; Jacob, Jencson

2018-05-01

Spitzer is pioneering a systematic exploration of the dynamic infrared sky. Our SPitzer InfraRed Intensive Transients Survey (SPIRITS) has already discovered 78 explosive transients and 2457 eruptive variables. Of these 78 infrared transients, 60 are so red that they are devoid of optical counterparts and we call them SPRITEs (eSPecially Red Intermediate-luminosity Transient Events). The nature of SPRITEs is unknown and progress on deciphering the explosion physics depends on mid-IR spectroscopy. Multiple physical origins have been proposed including stellar merger, birth of a massive binary, electron capture supernova and stellar black hole formation. Hence, we propose a modest continuation of SPIRITS, focusing on discovering and monitoring SPRITEs, in preparation for follow-up with the James Webb Space Telescope (JWST). As the SPRITEs evolve and cool, the bulk of the emission shifts to longer wavelengths. MIRI aboard JWST will be the only available platform in the near future capable of characterizing SPRITEs out to 28 um. Specifically, the low resolution spectrometer would determine dust mass, grain chemistry, ice abundance and energetics to disentangle the proposed origins. The re-focused SPIRITS program consists of continued Spitzer monitoring of those 106 luminous galaxies that are known SPRITE hosts or are most likely to host new SPRITEs. Scaling from the SPIRITS discovery rate, we estimate finding 10 new SPRITEs and 2-3 new supernovae in Cycle 14. The SPIRITS team remains committed to extensive ground-based follow-up. The Spitzer observations proposed here are essential for determining the final fates of active SPRITEs as well as bridging the time lag between the current SPIRITS survey and JWST launch.

VizieR Online Data Catalog: ALMA survey of protoplanetary disks in sigma Ori (Ansdell+, 2017)

NASA Astrophysics Data System (ADS)

Ansdell, M.; Williams, J. P.; Manara, C. F.; Miotello, A.; Facchini, S.; van der Marel, N.; Testi, L.; van Dishoeck, E. F.

2017-08-01

Our sample consists of the 92 Young Stellar Objects (YSOs) in σ Orionis with infrared excesses consistent with the presence of a protoplanetary disk. hese sources are identified by cross-matching the Class II and transition disk (TD) candidates from the Spitzer survey of Hernandez et al. 2007 (Cat. J/ApJ/662/1067) with the Mayrit catalog (Caballero 2008, Cat. J/A+A/478/667). Both catalogs are expected to be complete down to the brown dwarf limit. Disk classifications are based on the Spitzer/Infrared Array Camera (IRAC) Spectral Energy Distribution (SED) slope, as described in Hernandez et al. 2007 (Cat. J/ApJ/662/1067). We also include in our sample a Class I disk (source 1153), as it is located near the Spitzer/IRAC color cutoff for Class II disks. Our Band 6 Atacama Large Millimeter/sub-millimeter Array (ALMA) observations were obtained on 2016 July 30 and 31 during Cycle 3 (Project ID: 2015.1.00089.S; PI: Williams). The array configuration used 36 and 37 12m antennas on July 30 and 31, respectively, with baselines of 15-1124m on both runs. The correlator setup included two broadband continuum windows centered on 234.293 and 216.484GHz with bandwidths of 2.000 and 1.875GHz and channel widths of 15.625 and 0.976MHz, respectively. The bandwidth-weighted mean continuum frequency was 225.676GHz (1.33mm). The spectral windows covered the 12CO (230.538GHz), 13CO (220.399GHz), and C18O (219.560GHz) J=2-1 transitions at velocity resolutions of 0.16-0.17km/s. These spectral windows were centered on 230.531, 220.392, and 219.554GHz with bandwidths of 11.719MHz and channel widths of 0.122MHz. On-source integration times were 1.2 minutes per object for an average continuum rms of 0.15mJy/beam (Table1). This sensitivity was based on the James Clerk Maxwell Telescope (JCMT)/Submillimeter Common User Bolometer Array (SCUBA)-2 survey of σ Orionis disks by Williams et al. 2013 (Cat. J/MNRAS/435/1671), who found that stacking their individual non-detections revealed a mean 850μm continuum signal of 1.3mJy at 4σ significance. The sensitivity of our ALMA survey was therefore chosen to provide ~3-4σ detections of such disks at 1.3mm, based on an extrapolation of the 850μm mean signal using a spectral slope of α=2-3. Table1 presents the 1.33mm continuum flux densities and associated uncertainties (F1.33mm). Table2 gives our integrated line fluxes or upper limits. (2 data files).

Spitzer Sees Water Loud and Clear

NASA Image and Video Library

2007-08-29

This plot of infrared data, called a spectrum, shows the strong signature of water vapor deep within the core of an embryonic star system, called NGC 1333-IRAS 4B. The data were captured by NASA Spitzer Space Telescope.

AKARI/IRC source catalogues and source counts for the IRAC Dark Field, ELAIS North and the AKARI Deep Field South

NASA Astrophysics Data System (ADS)

Davidge, H.; Serjeant, S.; Pearson, C.; Matsuhara, H.; Wada, T.; Dryer, B.; Barrufet, L.

2017-12-01

We present the first detailed analysis of three extragalactic fields (IRAC Dark Field, ELAIS-N1, ADF-S) observed by the infrared satellite, AKARI, using an optimized data analysis toolkit specifically for the processing of extragalactic point sources. The InfaRed Camera (IRC) on AKARI complements the Spitzer Space Telescope via its comprehensive coverage between 8-24 μm filling the gap between the Spitzer/IRAC and MIPS instruments. Source counts in the AKARI bands at 3.2, 4.1, 7, 11, 15 and 18 μm are presented. At near-infrared wavelengths, our source counts are consistent with counts made in other AKARI fields and in general with Spitzer/IRAC (except at 3.2 μm where our counts lie above). In the mid-infrared (11 - 18 μm), we find our counts are consistent with both previous surveys by AKARI and the Spitzer peak-up imaging survey with the InfraRed Spectrograph (IRS). Using our counts to constrain contemporary evolutionary models, we find that although the models and counts are in agreement at mid-infrared wavelengths there are inconsistencies at wavelengths shortward of 7 μm, suggesting either a problem with stellar subtraction or indicating the need for refinement of the stellar population models. We have also investigated the AKARI/IRC filters, and find an active galactic nucleus selection criteria out to z < 2 on the basis of AKARI 4.1, 11, 15 and 18 μm colours.

INFRARED LUMINOSITIES AND DUST PROPERTIES OF z approx 2 DUST-OBSCURED GALAXIES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bussmann, R. S.; Dey, Arjun; Jannuzi, B. T.

We present SHARC-II 350 mum imaging of twelve 24 mum bright (F{sub 24m}u{sub m} > 0.8 mJy) Dust-Obscured Galaxies (DOGs) and Combined Array for Research in Millimeter-wave Astronomy (CARMA) 1 mm imaging of a subset of two DOGs. These objects are selected from the Booetes field of the NOAO Deep Wide-Field Survey. Detections of four DOGs at 350 mum imply infrared (IR) luminosities which are consistent to within a factor of 2 of expectations based on a warm-dust spectral energy distribution (SED) scaled to the observed 24 mum flux density. The 350 mum upper limits for the 8 non-detected DOGsmore » are consistent with both Mrk 231 and M82 (warm-dust SEDs), but exclude cold dust (Arp 220) SEDs. The two DOGs targeted at 1 mm were not detected in our CARMA observations, placing strong constraints on the dust temperature: T{sub dust} > 35-60 K. Assuming these dust properties apply to the entire sample, we find dust masses of approx3 x 10{sup 8} M{sub sun}. In comparison to other dusty z approx 2 galaxy populations such as submillimeter galaxies (SMGs) and other Spitzer-selected high-redshift sources, this sample of DOGs has higher IR luminosities (2 x 10{sup 13} L{sub sun} versus 6 x 10{sup 12} L{sub sun} for the other galaxy populations) that are driven by warmer dust temperatures (>35-60 K versus approx30 K) and lower inferred dust masses (3 x 10{sup 8} M{sub sun} versus 3 x 10{sup 9} M{sub sun}). Wide-field Herschel and Submillimeter Common-User Bolometer Array-2 surveys should be able to detect hundreds of these power-law-dominated DOGs. We use the existing Hubble Space Telescope and Spitzer/InfraRed Array Camera data to estimate stellar masses of these sources and find that the stellar to gas mass ratio may be higher in our 24 mum bright sample of DOGs than in SMGs and other Spitzer-selected sources. Although much larger sample sizes are needed to provide a definitive conclusion, the data are consistent with an evolutionary trend in which the formation of massive galaxies at z approx 2 involves a submillimeter bright, cold-dust, and star-formation-dominated phase followed by a 24 mum bright, warm-dust and AGN-dominated phase.« less

The Seven Sisters Pose for Spitzer

NASA Image and Video Library

2007-04-16

The Seven Sisters, also known as the Pleiades star cluster, seem to float on a bed of feathers in a new infrared image from NASA Spitzer Space Telescope. Clouds of dust sweep around the stars, swaddling them in a cushiony veil.

Spitzer Reveals Stellar Family Tree

NASA Image and Video Library

2008-08-22

Generations of stars can be seen in this new infrared portrait from NASA Spitzer Space Telescope. In this wispy star-forming region, called W5, the oldest stars can be seen as blue dots in the centers of the two hollow cavities.

Multi-Wavelength Views of Messier 81

NASA Technical Reports Server (NTRS)

2003-01-01

[figure removed for brevity, see original site] Click on individual images below for larger view

[figure removed for brevity, see original site]

[figure removed for brevity, see original site]

[figure removed for brevity, see original site]

[figure removed for brevity, see original site]

The magnificent spiral arms of the nearby galaxy Messier 81 are highlighted in this image from NASA's Spitzer Space Telescope. Located in the northern constellation of Ursa Major (which also includes the Big Dipper), this galaxy is easily visible through binoculars or a small telescope. M81 is located at a distance of 12 million light-years.

The main image is a composite mosaic obtained with the multiband imaging photometer for Spitzer and the infrared array camera. Thermal infrared emission at 24 microns detected by the photometer (red, bottom left inset) is combined with camera data at 8.0 microns (green, bottom center inset) and 3.6 microns (blue, bottom right inset).

A visible-light image of Messier 81, obtained at Kitt Peak National Observatory, a ground-based telescope, is shown in the upper right inset. Both the visible-light picture and the 3.6-micron near-infrared image trace the distribution of stars, although the Spitzer image is virtually unaffected by obscuring dust. Both images reveal a very smooth stellar mass distribution, with the spiral arms relatively subdued.

As one moves to longer wavelengths, the spiral arms become the dominant feature of the galaxy. The 8-micron emission is dominated by infrared light radiated by hot dust that has been heated by nearby luminous stars. Dust in the galaxy is bathed by ultraviolet and visible light from nearby stars. Upon absorbing an ultraviolet or visible-light photon, a dust grain is heated and re-emits the energy at longer infrared wavelengths. The dust particles are composed of silicates (chemically similar to beach sand), carbonaceous grains and polycyclic aromatic hydrocarbons and trace the gas distribution in the galaxy. The well-mixed gas (which is best detected at radio wavelengths) and dust provide a reservoir of raw materials for future star formation.

The 24-micron multiband imaging photometer image shows emission from warm dust heated by the most luminous young stars. The infrared-bright clumpy knots within the spiral arms show where massive stars are being born in giant H II (ionized hydrogen) regions. Studying the locations of these star forming regions with respect to the overall mass distribution and other constituents of the galaxy (e.g., gas) will help identify the conditions and processes needed for star formation.

Evidence for Infrared-faint Radio Sources as z > 1 Radio-loud Active Galactic Nuclei

NASA Astrophysics Data System (ADS)

Huynh, Minh T.; Norris, Ray P.; Siana, Brian; Middelberg, Enno

2010-02-01

Infrared-Faint Radio Sources (IFRSs) are a class of radio objects found in the Australia Telescope Large Area Survey which have no observable mid-infrared counterpart in the Spitzer Wide-area Infrared Extragalactic (SWIRE) survey. The extended Chandra Deep Field South now has even deeper Spitzer imaging (3.6-70 μm) from a number of Legacy surveys. We report the detections of two IFRS sources in IRAC images. The non-detection of two other IFRSs allows us to constrain the source type. Detailed modeling of the spectral energy distribution of these objects shows that they are consistent with high-redshift (z >~ 1) active galactic nuclei.

EVIDENCE FOR INFRARED-FAINT RADIO SOURCES AS z > 1 RADIO-LOUD ACTIVE GALACTIC NUCLEI

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huynh, Minh T.; Norris, Ray P.; Siana, Brian

2010-02-10

Infrared-Faint Radio Sources (IFRSs) are a class of radio objects found in the Australia Telescope Large Area Survey which have no observable mid-infrared counterpart in the Spitzer Wide-area Infrared Extragalactic (SWIRE) survey. The extended Chandra Deep Field South now has even deeper Spitzer imaging (3.6-70 {mu}m) from a number of Legacy surveys. We report the detections of two IFRS sources in IRAC images. The non-detection of two other IFRSs allows us to constrain the source type. Detailed modeling of the spectral energy distribution of these objects shows that they are consistent with high-redshift (z {approx}> 1) active galactic nuclei.

Hubble Space Telescope,Spitzer Space Telescope

NASA Image and Video Library

2018-01-11

This image showcases both the visible and infrared visualizations of the Orion Nebula. This view from a movie sequence looks down the 'valley' leading to the star cluster at the far end. The left side of the image shows the visible-light visualization, which fades to the infrared-light visualization on the right. These two contrasting models derive from observations by the Hubble and Spitzer space telescopes. An animation is available at https://photojournal.jpl.nasa.gov/catalog/PIA22089

SPIRITS: Uncovering Unusual Infrared Transients with Spitzer

NASA Astrophysics Data System (ADS)

Kasliwal, Mansi M.; Bally, John; Masci, Frank; Cody, Ann Marie; Bond, Howard E.; Jencson, Jacob E.; Tinyanont, Samaporn; Cao, Yi; Contreras, Carlos; Dykhoff, Devin A.; Amodeo, Samuel; Armus, Lee; Boyer, Martha; Cantiello, Matteo; Carlon, Robert L.; Cass, Alexander C.; Cook, David; Corgan, David T.; Faella, Joseph; Fox, Ori D.; Green, Wayne; Gehrz, R. D.; Helou, George; Hsiao, Eric; Johansson, Joel; Khan, Rubab M.; Lau, Ryan M.; Langer, Norbert; Levesque, Emily; Milne, Peter; Mohamed, Shazrene; Morrell, Nidia; Monson, Andy; Moore, Anna; Ofek, Eran O.; O' Sullivan, Donal; Parthasarathy, Mudumba; Perez, Andres; Perley, Daniel A.; Phillips, Mark; Prince, Thomas A.; Shenoy, Dinesh; Smith, Nathan; Surace, Jason; Van Dyk, Schuyler D.; Whitelock, Patricia A.; Williams, Robert

2017-04-01

We present an ongoing, five-year systematic search for extragalactic infrared transients, dubbed SPIRITS—SPitzer InfraRed Intensive Transients Survey. In the first year, using Spitzer/IRAC, we searched 190 nearby galaxies with cadence baselines of one month and six months. We discovered over 1958 variables and 43 transients. Here, we describe the survey design and highlight 14 unusual infrared transients with no optical counterparts to deep limits, which we refer to as SPRITEs (eSPecially Red Intermediate-luminosity Transient Events). SPRITEs are in the infrared luminosity gap between novae and supernovae, with [4.5] absolute magnitudes between -11 and -14 (Vega-mag) and [3.6]-[4.5] colors between 0.3 mag and 1.6 mag. The photometric evolution of SPRITEs is diverse, ranging from <0.1 mag yr-1 to >7 mag yr-1. SPRITEs occur in star-forming galaxies. We present an in-depth study of one of them, SPIRITS 14ajc in Messier 83, which shows shock-excited molecular hydrogen emission. This shock may have been triggered by the dynamic decay of a non-hierarchical system of massive stars that led to either the formation of a binary or a protostellar merger.

SPIRITS: Uncovering Unusual Infrared Transients with Spitzer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kasliwal, Mansi M.; Jencson, Jacob E.; Tinyanont, Samaporn

2017-04-20

We present an ongoing, five-year systematic search for extragalactic infrared transients, dubbed SPIRITS—SPitzer InfraRed Intensive Transients Survey. In the first year, using Spitzer /IRAC, we searched 190 nearby galaxies with cadence baselines of one month and six months. We discovered over 1958 variables and 43 transients. Here, we describe the survey design and highlight 14 unusual infrared transients with no optical counterparts to deep limits, which we refer to as SPRITEs (eSPecially Red Intermediate-luminosity Transient Events). SPRITEs are in the infrared luminosity gap between novae and supernovae, with [4.5] absolute magnitudes between −11 and −14 (Vega-mag) and [3.6]–[4.5] colors betweenmore » 0.3 mag and 1.6 mag. The photometric evolution of SPRITEs is diverse, ranging from <0.1 mag yr{sup −1} to >7 mag yr{sup −1}. SPRITEs occur in star-forming galaxies. We present an in-depth study of one of them, SPIRITS 14ajc in Messier 83, which shows shock-excited molecular hydrogen emission. This shock may have been triggered by the dynamic decay of a non-hierarchical system of massive stars that led to either the formation of a binary or a protostellar merger.« less

Devastated Stellar Neighborhood

NASA Technical Reports Server (NTRS)

2008-01-01

This image from NASA's Spitzer Space Telescope shows the nasty effects of living near a group of massive stars: radiation and winds from the massive stars (white spot in center) are blasting planet-making material away from stars like our sun. The planetary material can be seen as comet-like tails behind three stars near the center of the picture. The tails are pointing away from the massive stellar furnaces that are blowing them outward.

The picture is the best example yet of multiple sun-like stars being stripped of their planet-making dust by massive stars.

The sun-like stars are about two to three million years old, an age when planets are thought to be growing out of surrounding disks of dust and gas. Astronomers say the dust being blown from the stars is from their outer disks. This means that any Earth-like planets forming around the sun-like stars would be safe, while outer planets like Uranus might be nothing more than dust in the wind.

This image shows a portion of the W5 star-forming region, located 6,500 light-years away in the constellation Cassiopeia. It is a composite of infrared data from Spitzer's infrared array camera and multiband imaging photometer. Light with a wavelength of 3.5 microns is blue, while light from the dust of 24 microns is orange-red.

CALISTO - A Novel Architecture for the Single Aperture Far Infrared Observatory

NASA Astrophysics Data System (ADS)

Lester, Daniel F.; Goldsmith, P.; Benford, D.

2007-12-01

Following the success of Spitzer, and in expectation of success with JWST and Herschel, the astronomical community is looking ahead to a large aperture far infrared mission that can build on the scientific results of these missions. This expectation was formalized by the 2000 Decadal recommendation for design studies on a SAFIR - a single aperture far infrared observatory. A JWST-inspired architecture for SAFIR was considered in a Vision Mission study several years ago. We present here a exciting new architecture for this important mission that offers several advantages. This CALISTO (Cryogenic Far-Infrared/Submillimeter Observatory) architecture, originally developed by JPL, builds on the thermally optimized passive cooling design of the Vision Mission version of SAFIR, and focal plane instrument strategies as well, but is based on a 4x6m ellipsoidal primary that greatly simplifies deployment out of an ELV launch shroud. Used off-axis, this design is much less affected by scattered (e.g. galactic plane and ZODI) emission than previous architectures, providing astronomical background-limited facility over much of the sky. Technologies for such a large mirror, diffraction-limited at 20µm, are now becoming credible. Using the large focal plane to host envisioned large format sensor arrays operating with high spatial resolution, CALISTO will resolve the far infrared extragalactic background, and trace the chemical evolution of galaxies. Simple models suggest that detection of the first structure in the universe, marked by cooling primordial clouds of molecular hydrogen at high z, may be achievable with such a telescope. Further building on the work of Spitzer, CALISTO will trace the development of planetary systems, probing the inner structure of star forming disks, and reveal the structure of nearby solar systems using the structure of debris disks that surround them. We review in this paper the science goals and engineering challenges for this mission.

A Giant Gathering of Galaxies

NASA Image and Video Library

2015-11-03

The galaxy cluster called MOO J1142+1527 can be seen here as it existed when light left it 8.5 billion years ago. The red galaxies at the center of the image make up the heart of the galaxy cluster. This color image is constructed from multi-wavelength observations: Infrared observations from NASA's Spitzer Space Telescope are shown in red; near-infrared and visible light captured by the Gemini Observatory atop Mauna Kea in Hawaii is green and blue; and radio light from the Combined Array for Research in Millimeter-wave Astronomy (CARMA), near Owens Valley in California, is purple. In addition to galaxies, clusters also contain a reservoir of hot gas with temperatures in the tens of millions of degrees Celsius/Kelvin. CARMA was used to detect this gas, and to determine the mass of this cluster. http://photojournal.jpl.nasa.gov/catalog/PIA20052

Galaxies Collide to Create Hot, Huge Galaxy

NASA Technical Reports Server (NTRS)

2009-01-01

This image of a pair of colliding galaxies called NGC 6240 shows them in a rare, short-lived phase of their evolution just before they merge into a single, larger galaxy. The prolonged, violent collision has drastically altered the appearance of both galaxies and created huge amounts of heat turning NGC 6240 into an 'infrared luminous' active galaxy.

A rich variety of active galaxies, with different shapes, luminosities and radiation profiles exist. These galaxies may be related astronomers have suspected that they may represent an evolutionary sequence. By catching different galaxies in different stages of merging, a story emerges as one type of active galaxy changes into another. NGC 6240 provides an important 'missing link' in this process.

This image was created from combined data from the infrared array camera of NASA's Spitzer Space Telescope at 3.6 and 8.0 microns (red) and visible light from NASA's Hubble Space Telescope (green and blue).

Cosmic Sparklers

NASA Image and Video Library

2015-07-02

This new composite image of stellar cluster NGC 1333 combines X-rays from NASA's Chandra X-ray Observatory (pink); infrared data from NASA's Spitzer Space Telescope (red); and optical data from the Digitized Sky Survey and the National Optical Astronomical Observatories' Mayall 4-meter telescope on Kitt Peak near Tucson, Arizona. The Chandra data reveal 95 young stars glowing in X-ray light, 41 of which had not been seen previously using Spitzer because they lacked infrared emission from a surrounding disk. http://photojournal.jpl.nasa.gov/catalog/PIA19347

Infrared Faint Radio Sources in the Extended Chandra Deep Field South

NASA Astrophysics Data System (ADS)

Huynh, Minh T.

2009-01-01

Infrared-Faint Radio Sources (IFRSs) are a class of radio objects found in the Australia Telescope Large Area Survey (ATLAS) which have no observable counterpart in the Spitzer Wide-area Infrared Extragalactic Survey (SWIRE). The extended Chandra Deep Field South now has even deeper Spitzer imaging (3.6 to 70 micron) from a number of Legacy surveys. We report the detections of two IFRS sources in IRAC images. The non-detection of two other IFRSs allows us to constrain the source type. Detailed modeling of the SED of these objects shows that they are consistent with high redshift AGN (z > 2).

The impact of Spitzer infrared data on stellar mass estimates - and a revised galaxy stellar mass function at 0 < z < 5

NASA Astrophysics Data System (ADS)

Elsner, F.; Feulner, G.; Hopp, U.

2008-01-01

Aims:We estimate stellar masses of galaxies in the high redshift universe with the intention of determining the influence of newly available Spitzer/IRAC infrared data on the analysis. Based on the results, we probe the mass assembly history of the universe. Methods: We use the GOODS-MUSIC catalog, which provides multiband photometry from the U-filter to the 8 μm Spitzer band for almost 15 000 galaxies with either spectroscopic (for ≈7% of the sample) or photometric redshifts, and apply a standard model fitting technique to estimate stellar masses. We than repeat our calculations with fixed photometric redshifts excluding Spitzer photometry and directly compare the outcomes to look for systematic deviations. Finally we use our results to compute stellar mass functions and mass densities up to redshift z = 5. Results: We find that stellar masses tend to be overestimated on average if further constraining Spitzer data are not included into the analysis. Whilst this trend is small up to intermediate redshifts z ⪉ 2.5 and falls within the typical error in mass, the deviation increases strongly for higher redshifts and reaches a maximum of a factor of three at redshift z ≈ 3.5. Thus, up to intermediate redshifts, results for stellar mass density are in good agreement with values taken from literature calculated without additional Spitzer photometry. At higher redshifts, however, we find a systematic trend towards lower mass densities if Spitzer/IRAC data are included.

Infrared radiation from hot Jupiters

NASA Astrophysics Data System (ADS)

Deming, D.; Richardson, L. J.; Seager, S.; Harrington, J.

2006-02-01

Recent Spitzer infrared (IR) observations of two transiting hot Jupiters during their secondary eclipses have provided the first direct detection of planets orbiting other stars (Charbonneau et al. 2005, ApJ 626, 523; Deming et al. 2005, Nature 434, 740). We here elaborate on some aspects of our detection of HD 209458b at 24 μm, and we compare to the detection of TrES-1 by Charbonneau et al. Spitzer will eventually determine the IR spectral energy distribution of these and similar hot Jupiters, opening the new field of comparative exoplanetology. For now, we have only three Spitzer data points, augmented by upper limits from the ground. We here interpret the available measurements from a purely observational perspective, and we point out that a blackbody spectrum having T ˜ 1100K can account for all current IR measurements, within the errors. This will surely not remain true for long, since ongoing Spitzer observations will be very sensitive to the IR characteristics of hot Jupiters.

Reconciling the Census of Forming Stars in Gould's Belt

NASA Astrophysics Data System (ADS)

Gutermath, Robert

We seek funding to construct a set of new, publicly available, value-enhanced data products for the 37 deg2 of archival Spitzer IRAC 3-8 micron and MIPS 24 micron imaging from the Spitzer Legacy surveys From Molecular Cores to Planet-forming Disks (PI Evans) and the subsequent Gould's Belt: Star Formation in the Solar Neighborhood (PI Allen; c2d/GB hereafter). These surveys comprise our canonical view of low-mass star formation, encompassing most of the nearest (<400pc) molecular clouds other than Taurus. From the proposed c2d/GB reprocessing, we will produce and deliver the following products to the Infrared Science Archive (IRSA) at IPAC for community access: - Artifact-mitigated, astrometrically-refined Spitzer mosaics at 3.6, 4.5, 5.8, 8.0, and 24 microns for all 18 clouds in c2d/GB; - Complete, band-merged, point source catalogs in all five Spitzer bands considered, combined with 2MASS and WISE photometry where available, and a census of young stellar objects (YSOs) with excess infrared emission that are selected via the Gutermuth et al. (2009; G09) YSO identification and classification techniques from the full catalogs; - Point source completeness decay data cubes at 30'' resolution for all Spitzer mosaics, and midIR luminosity completeness images built from the five-band completeness cubes for a wide range of mid-IR spectral energy distribution (SED) shapes. Our overarching goal is to provide a precise observational product that contains the means to test ever more detailed simulations of star formation and guide and supplement future observations of nearby star-forming regions and clouds at all wavelengths. A complete, internally consistent census of all YSOs exhibiting excess infrared emission and a detailed mapping of the limits of non-detections by YSO evolutionary stage for all molecular clouds and star-forming complexes observed by Spitzer within 2 kpc will have incredible value for both goals. With a full YSO census and a clearer understanding of how to interpret any lack of YSOs spatially within a wide range of clouds, we will address three fundamental lines of inquiry across a wide range of local star-forming environments: - What is the protostellar phase lifetime? How does it correlate with the star formation efficiency of molecular gas? - What is the shape of the protostellar luminosity function? Does it vary with molecular gas properties? - Which dense pre-stellar gas cores are starless ? More specifically, what YSO luminosity limits can we exclude in starless cores with the Spitzer surveys? Most of the c2d/GB cloud surveys have been analyzed and published by the original teams, and they have now largely dispersed (two of this proposal's investigators were members of one or both surveys). In parallel, the G09 techniques that were developed for a survey of 36 nearby starforming clusters and groups were adopted for a wide array of YSO surveys of more distant starforming molecular clouds (400-2000pc). These are observed similarly to the c2d/GB surveys, and thus the G09 techniques are readily applicable to the nearest clouds. Indeed, the c2d/GB YSO census overlaps with several clusters in the original G09 clusters survey, and substantial inconsistencies have been found between the corresponding YSO catalogs. Attempts to conduct broad comparisons and interpretation among c2d/GB and G09-family catalogs have been clearly limited by method-dependent differences. Reconciliation of these discrepancies is essential to establish a consistent census of YSOs and enable further scientific progress on these topics.

The Sword of Orion

NASA Technical Reports Server (NTRS)

2006-01-01

[figure removed for brevity, see original site] [figure removed for brevity, see original site] AnimationFigure 1

This infrared image from NASA's Spitzer Space Telescope shows the Orion nebula, our closest massive star-making factory, 1,450 light-years from Earth. The nebula is close enough to appear to the naked eye as a fuzzy star in the sword of the popular hunter constellation.

The nebula itself is located on the lower half of the image, surrounded by a ring of dust. It formed in a cold cloud of gas and dust and contains about 1,000 young stars. These stars illuminate the cloud, creating the beautiful nebulosity, or swirls of material, seen here in infrared.

In the center of the nebula (bottom inset of figure 1) are four monstrously massive stars, up to 100,000 times as luminous as our sun, called the Trapezium (tiny yellow smudge to the lower left of green splotches. Radiation and winds from these stars are blasting gas and dust away, excavating a cavity walled in by the large ring of dust.

Behind the Trapezium, still buried deeply in the cloud, a second generation of massive stars is forming (in the area with green splotches). The speckled green fuzz in this bright region is created when bullets of gas shoot out from the juvenile stars and ram into the surrounding cloud.

Above this region of intense activity are networks of cold material that appear as dark veins against the pinkish nebulosity (upper inset pf figure 1). These dark veins contain embryonic stars. Some of the natal stars illuminate the cloud, creating small, aqua-colored wisps. In addition, jets of gas from the stars ram into the cloud, resulting in the green horseshoe-shaped globs.

Spitzer surveyed a significant swath of the Orion constellation, beyond what is highlighted in this image. Within that region, called the Orion cloud complex, the telescope found 2,300 stars circled by disks of planet-forming dust and 200 stellar embryos too young to have developed disks.

This image shows infrared light captured by Spitzer's infrared array camera. Light with wavelengths of 8 and 5.8 microns (red and orange) comes mainly from dust that has been heated by starlight. Light of 4.5 microns (green) shows hot gas and dust; and light of 3.6 microns (blue) is from starlight.

VizieR Online Data Catalog: Spitzer and VRIJHK photometry of V582 Mon (Arulanantham+, 2016)

NASA Astrophysics Data System (ADS)

Arulanantham, N. A.; Herbst, W.; Cody, A. M.; Stauffer, J. R.; Rebull, L. M.; Agol, E.; Windemuth, D.; Marengo, M.; Winn, J. N.; Hamilton, C. M.; Mundt, R.; Johns-Krull, C. M.; Gutermuth, R. A.

2016-07-01

We have continued to obtain ground-based optical and near-infrared photometry over the last two years using A Novel Dual Imaging CAMera (ANDICAM) on the 1.3m telescope at Cerro-Tololo Inter-American Observatory (CTIO) in Chile. The instrument is operated by the SMARTS consortium. Data were collected almost nightly from 2013 October through 2014 April. Observations were resumed in 2014 September and continued until 2015 April. Each night, four 150s exposures were obtained in each of the three optical bands (VRI) along with 10-15 dithered exposures (30s each) in the near-infrared bands (JHK). All images have a 10.2'*10.2' field of view. The data acquisition and reduction processes are discussed briefly in Appendix A, and a more complete description is given by Windemuth & Herbst 2014 (cat. J/AJ/147/9). The VRIJHK magnitudes from the last two observing seasons have been added to the entire set of CCD data obtained since 1995, which is presented here as Table1. Images of KH 15D were collected with the InfraRed Array Camera (IRAC) on the Spitzer Space Telescope during six observational runs with five separate PI's spanning three distinct epochs since 2004 (2004 Mar 6 and 2004 Oct 08, PI Giovanni Fazio, Program ID=37; 2004 Oct 5-12 and 2005 Oct 21-29, PI Massimo Marengo, Program ID=3441; 2006 Mar 23-27, PI Eric Agol, Program ID=3469; 2008 Nov 1-2, PI Lucas A. Cieza, Program ID=50773). The fifth set of observations was obtained by the CSI 2264 team (PI=John R. Stauffer, Program ID=61027, 80040) as part of a large campaign to monitor young variable objects in NGC2264 (Cody et al. 2014, cat. J/AJ/147/82). These data were obtained over 28 consecutive days of observation in 2011 December (2011 Dec 3-2012 Jan 1). A final set of observations was obtained on eight nights between 2013 December and 2014 January (2013 Dec 22-2014 Jan 20, PI William Herbst, Program ID=90154, 90098). The full set of Spitzer photometry at all epochs is given in Table3. (2 data files).

Spitzer - Hot & Colorful Student Activities

NASA Astrophysics Data System (ADS)

McDonald, D.; Rebull, L. M.; DeWolf, C.; Guastella, P.; Johnson, C. H.; Schaefers, J.; Spuck, T.; McDonald, J. G., III; DeWolf, T.; Brock, S.; Boerma, J.; Bemis, G.; Paulsen, K.; Yueh, N.; Peter, A.; Wassmer, W.; Haber, R.; Scaramucci, A.; Butchart, J.; Holcomb, A.; Karns, B.; Kennedy, S.; Siegel, R.; Weiser, S.

2009-01-01

In this poster, we present the results of several activities developed for the general science student to explore infrared light. The first activity involved measuring infrared radiation using an updated version of Newton's experiment of splitting white light and finding IR radiation. The second used Leslie's cube to allow students to observe different radiators, while the third used a modern infrared thermometer to measure and identify IR sources in an enclosed box. The last activity involved students making false-color images from narrow-band filter images from data sets from Spitzer Space Telescope, STScI Digitized Sky Survey and other sources. Using computer programs like Adobe Photoshop and free software such as ds9, Spot and Leopard, poster-like images were created by the students. This research is funded by the Spitzer Science Center (SSC) and the National Optical Astronomy Observatory (NOAO). Please see our companion poster, Johnson et al., on the science aspect of this program, and another poster on the educational aspects, Guastella et al.

Cracking the Code of Faraway Worlds

NASA Technical Reports Server (NTRS)

2007-01-01

This infrared data from NASA's Spitzer Space Telescope - called a spectrum - tells astronomers that a distant gas planet, a so-called 'hot Jupiter' called HD 209458b, might be smothered with high clouds. It is one of the first spectra of an alien world.

A spectrum is created when an instrument called a spectrograph cracks light from an object open into a rainbow of different wavelengths. Patterns or ripples within the spectrum indicate the presence, or absence, of molecules making up the object.

Astronomers using Spitzer's spectrograph were able to obtain infrared spectra for two so-called 'transiting' hot-Jupiter planets using the 'secondary eclipse' technique. In this method, the spectrograph first collects the combined infrared light from the planet plus its star, then, as the planet is eclipsed by the star, the infrared light of just the star. Subtracting the latter from the former reveals the planet's own rainbow of infrared colors.

When astronomers first saw the infrared spectrum above, they were shocked. It doesn't look anything like what theorists had predicted. For example, theorists thought there'd be signatures of water in the wavelength ranges of 8 to 9 microns. The fact that water is not detected might indicate that it is hidden under a thick blanket of high, dry clouds.

In addition, the spectrum shows signs of silicate dust -- tiny grains of sand -- in the wavelength range of 9 to 10 microns. This suggests that the planet's skies could be filled with high clouds of dust unlike anything seen in our own solar system.

There is also an unidentified molecular signature at 7.78 microns. Future observations using Spitzer's spectrograph should be able to determine the nature of the mysterious feature.

This spectrum was produced by Dr. Jeremy Richardson of NASA's Goddard Space Flight Center, Greenbelt, Md. and his colleagues. The data were taken by Spitzer's infrared spectrograph on July 6 and 13, 2005.

Cracking the Code of Faraway Worlds

NASA Image and Video Library

2007-02-21

This infrared data from NASA's Spitzer Space Telescope -- called a spectrum -- tells astronomers that a distant gas planet, a so-called "hot Jupiter" called HD 209458b, might be smothered with high clouds. It is one of the first spectra of an alien world. A spectrum is created when an instrument called a spectrograph cracks light from an object open into a rainbow of different wavelengths. Patterns or ripples within the spectrum indicate the presence, or absence, of molecules making up the object. Astronomers using Spitzer's spectrograph were able to obtain infrared spectra for two so-called "transiting" hot-Jupiter planets using the "secondary eclipse" technique. In this method, the spectrograph first collects the combined infrared light from the planet plus its star, then, as the planet is eclipsed by the star, the infrared light of just the star. Subtracting the latter from the former reveals the planet's own rainbow of infrared colors. When astronomers first saw the infrared spectrum above, they were shocked. It doesn't look anything like what theorists had predicted. For example, theorists thought there'd be signatures of water in the wavelength ranges of 8 to 9 microns. The fact that water is not detected might indicate that it is hidden under a thick blanket of high, dry clouds. In addition, the spectrum shows signs of silicate dust -- tiny grains of sand -- in the wavelength range of 9 to 10 microns. This suggests that the planet's skies could be filled with high clouds of dust unlike anything seen in our own solar system. There is also an unidentified molecular signature at 7.78 microns. Future observations using Spitzer's spectrograph should be able to determine the nature of the mysterious feature. This spectrum was produced by Dr. Jeremy Richardson of NASA's Goddard Space Flight Center, Greenbelt, Md. and his colleagues. The data were taken by Spitzer's infrared spectrograph on July 6 and 13, 2005. http://photojournal.jpl.nasa.gov/catalog/PIA09197

Cracking the Code of Faraway Worlds

NASA Image and Video Library

2007-02-21

This infrared data from NASA's Spitzer Space Telescope -- called a spectrum -- tells astronomers that a distant gas planet, a so-called "hot Jupiter" called HD 209458b, might be smothered with high clouds. It is one of the first spectra of an alien world. A spectrum is created when an instrument called a spectrograph cracks light from an object open into a rainbow of different wavelengths. Patterns or ripples within the spectrum indicate the presence, or absence, of molecules making up the object. Astronomers using Spitzer's spectrograph were able to obtain infrared spectra for two so-called "transiting" hot-Jupiter planets using the "secondary eclipse" technique. In this method, the spectrograph first collects the combined infrared light from the planet plus its star, then, as the planet is eclipsed by the star, the infrared light of just the star. Subtracting the latter from the former reveals the planet's own rainbow of infrared colors. When astronomers first saw the infrared spectrum above, they were shocked. It doesn't look anything like what theorists had predicted. For example, theorists thought there'd be signatures of water in the wavelength ranges of 8 to 9 microns. The fact that water is not detected might indicate that it is hidden under a thick blanket of high, dry clouds. In addition, the spectrum shows signs of silicate dust -- tiny grains of sand -- in the wavelength range of 9 to 10 microns. This suggests that the planet's skies could be filled with high clouds of dust unlike anything seen in our own solar system. There is also an unidentified molecular signature at 7.78 microns. Future observations using Spitzer's spectrograph should be able to determine the nature of the mysterious feature. This spectrum was produced by Dr. Jeremy Richardson of NASA's Goddard Space Flight Center, Greenbelt, Md. and his colleagues. The data were taken by Spitzer's infrared spectrograph on July 6 and 13, 2005. http://photojournal.jpl.nasa.gov/catalog/PIA09198

The Infrared Spectrograph on the Spitzer Space Telescope

NASA Technical Reports Server (NTRS)

Roellig, Thomas L.

2017-01-01

The Infrared Spectrograph (IRS) instrument on the Spitzer Space Telescope covered the 5 to 38 micron wavelength range at low and medium spectral resolutions. The instrument was very popular during Spitzers 5.7 year-long cold mission. Every year it attracted the most proposals, and garnered more observing hours, of any of the science instruments. This success was the culmination of a very long development period, where the instrument design changed radically. When the instrument was first selected by NASA in 1984 it was very complicated. As part of the overall reduction of the size of the SIRTF Observatory following its recovery from the missions cancellation in 1991 the IRS became smaller and much, much simpler. The only aspect of the instrument that increased from the original design was the pixel count of the detectors.

The Spitzer-HETDEX Exploratory Large-area Survey

NASA Astrophysics Data System (ADS)

Papovich, C.; Shipley, H. V.; Mehrtens, N.; Lanham, C.; Lacy, M.; Ciardullo, R.; Finkelstein, S. L.; Bassett, R.; Behroozi, P.; Blanc, G. A.; de Jong, R. S.; DePoy, D. L.; Drory, N.; Gawiser, E.; Gebhardt, K.; Gronwall, C.; Hill, G. J.; Hopp, U.; Jogee, S.; Kawinwanichakij, L.; Marshall, J. L.; McLinden, E.; Mentuch Cooper, E.; Somerville, R. S.; Steinmetz, M.; Tran, K.-V.; Tuttle, S.; Viero, M.; Wechsler, R.; Zeimann, G.

2016-06-01

We present post-cryogenic Spitzer imaging at 3.6 and 4.5 μm with the Infrared Array Camera (IRAC) of the Spitzer/HETDEX Exploratory Large-Area (SHELA) survey. SHELA covers ≈24 deg2 of the Sloan Digital Sky Survey “Stripe 82” region, and falls within the footprints of the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) and the Dark Energy Survey. The HETDEX blind R ˜ 800 spectroscopy will produce ˜200,000 redshifts from the Lyα emission for galaxies in the range 1.9 < z < 3.5, and an additional ˜200,000 redshifts from the [O II] emission for galaxies at z < 0.5. When combined with deep ugriz images from the Dark Energy Camera, K-band images from NEWFIRM, and other ancillary data, the IRAC photometry from Spitzer will enable a broad range of scientific studies of the relationship between structure formation, galaxy stellar mass, halo mass, the presence of active galactic nuclei, and environment over a co-moving volume of ˜0.5 Gpc3 at 1.9 < z < 3.5. Here, we discuss the properties of the SHELA IRAC data set, including the data acquisition, reduction, validation, and source catalogs. Our tests show that the images and catalogs are 80% (50%) complete to limiting magnitudes of 22.0 (22.6) AB mag in the detection image, which is constructed from the weighted sum of the IRAC 3.6 and 4.5 μm images. The catalogs reach limiting sensitivities of 1.1 μJy at both 3.6 and 4.5 μm (1σ, for R = 2″ circular apertures). As a demonstration of the science, we present IRAC number counts, examples of highly temporally variable sources, and galaxy surface density profiles of rich galaxy clusters. In the spirit of the Spitzer Exploratory programs, we provide all of the images and catalogs as part of the publication.

The Vital Infrared to X-ray Link in the Sgr A* Accretion Flow

NASA Astrophysics Data System (ADS)

Fazio, Giovanni; Ashby, Matthew; Baganoff, Frederick; Becklin, Eric; Boyce, Hope; Carey, Sean; Gammie, Charles; Ghez, Andrea; Glaccum, William; Gurwell, Mark; Haggard, Daryl; Herrero-Illana, Ruben; Hora, Joseph; Ingalls, James; Lowrance, Patrick; Markoff, Sera; Marrone, Daniel; Morris, Mark; Narayan, Ramesh; Neilsen, Joseph; Ponti, Gabriele; Smith, Howard; Willner, Steven; Witzel, Gunther

2018-05-01

Black hole accretion drives extreme astrophysical phenomena in the universe. Sgr A*, the radiating counterpart of the nearest supermassive black hole, is highly variable, but sparse data and short observations have left its emission physics in question. Despite enormous advances in accretion models, physical description of the interacting radiation mechanisms is incomplete. The X-ray emission mechanism in particular remains unknown. Because the necessary information is contained in the time-dependent relation between X-ray and infrared emission, we have begun monitoring Sgr A* simultaneously with Chandra in X-rays and with Spitzer in the infrared. Defining the X-ray to infrared flux density ratio will allow the entire energy distribution to be understood. We therefore request two new 24-hour epochs of Spitzer monitoring at 4.5 microns simultaneous with Chandra time already approved. This will increase the exposure time for X-ray flares where the NIR state is known, moving us out of the realm of small-number statistics and enabling diagnostics of the true X-ray/IR ratio. Under current NASA plans, this will be the last chance for these valuable Spitzer+Chandra observations.

VizieR Online Data Catalog: z>~5 AGN in Chandra Deep Field-South (Weigel+, 2015)

NASA Astrophysics Data System (ADS)

Weigel, A. K.; Schawinski, K.; Treister, E.; Urry, C. M.; Koss, M.; Trakhtenbrot, B.

2015-09-01

The Chandra 4-Ms source catalogue by Xue et al. (2011, Cat. J/ApJS/195/10) is the starting point of this work. It contains 740 sources and provides counts and observed frame fluxes in the soft (0.5-2keV), hard (2-8keV) and full (0.5-8keV) band. All object IDs used in this work refer to the source numbers listed in the Xue et al. (2011, Cat. J/ApJS/195/10) Chandra 4-Ms catalogue. We make use of Hubble Space Telescope (HST)/Advanced Camera for Surveys (ACS) data from the Great Observatories Origins Deep Survey South (GOODS-south) in the optical wavelength range. We use catalogues and images for filters F435W (B), F606W (V), F775W (i) and 850LP (z) from the second GOODS/ACS data release (v2.0; Giavalisco et al., 2004, Cat. II/261). We use Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) Wide Field Camera 3 (WFC3)/infrared data from the first data release (DR1, v1.0) for passbands F105W (Y), F125W (J) and F160W (H) (Grogin et al., 2011ApJS..197...35G; Koekemoer et al., 2011ApJS..197...36K). To determine which objects are red, dusty, low-redshift interlopers, we also include the 3.6 and 4.5 micron Spitzer Infrared Array Camera (IRAC) channels. We use SIMPLE image data from the DR1 (van Dokkum et al., 2005, Spitzer Proposal, 2005.20708) and the first version of the extended SIMPLE catalogue by Damen et al. (2011, Cat. J/ApJ/727/1). (6 data files).

Detection of Planetary Emission from the Exoplanet TrES-2 Using Spitzer/IRAC

NASA Technical Reports Server (NTRS)

Donovan, Francis T.; Charbonneau, David; Harrington, Joseph; Madhusudhan, N.; Seager, Sara; Deming, Drake; Knutson, Heather A.

2010-01-01

We present here the results of our observations of TrES-2 using the Infrared Array Camera on Spitzer. We monitored this transiting system during two secondary eclipses, when the planetary emission is blocked by the star. The resulting decrease in flux is 0.127% +/- 0.021%, 0.230% +/- 0.024%, 0.199% +/- 0.054%, and 0.359% +/- 0.060% at 3.6 microns, 4.5 microns, 5.8 microns, and 8.0 microns, respectively. We show that three of these flux contrasts are well fit by a blackbody spectrum with T(sub eff) = 1500 K, as well as by a more detailed model spectrum of a planetary atmosphere. The observed planet-to-star flux ratios in all four lRAC channels can be explained by models with and without a thermal inversion in the atmosphere of TrES-2, although with different atmospheric chemistry. Based on the assumption of thermochemical equilibrium, the chemical composition of the inversion model seems more plausible, making it a more favorable scenario. TrES-2 also falls in the category of highly irradiated planets which have been theoretically predicted to exhibit thermal inversions. However, more observations at infrared and visible wavelengths would be needed to confirm a thermal inversion in this system. Furthermore, we find that the times of the secondary eclipses are consistent with previously published times of transit and the expectation from a circular orbit. This implies that TrES-2 most likely has a circular orbit, and thus does not obtain additional thermal energy from tidal dissipation of a non-zero orbital eccentricity, a proposed explanation for the large radius of this planet. Key words: eclipses - infrared: stars - planetary systems - stars: individual (OSC 03549-02811) - techniques: photometric

Diogenite-like Features in the Spitzer IRS (5-35 micrometers) Spectrum of 956 ELISA

NASA Technical Reports Server (NTRS)

Lim, Lucy F.; Emery, Joshua P.; Moskovitz, Nicholas A.

2009-01-01

We report preliminary results from the Spitzer Infrared Spectrograph (IRS) observations of the V-type asteroid 956 Elisa. Elisa was observed as part of a campaign to measure the 5.2-38 micron spectra of small basaltic asteroids with the Spitzer IRS. Targets include members of the dynamical family of the unique large differentiated asteroid 4 Vesta ("Vesroids"), several outer-main-belt basaltic asteroids whose orbits exclude them from originating on 4 Vesta, and the basaltic near-Earth asteroid 4055 Magellan.

VizieR Online Data Catalog: Spitzer obs. of warm dust in 83 debris disks (Ballering+, 2017)

NASA Astrophysics Data System (ADS)

Ballering, N. P.; Rieke, G. H.; Su, K. Y. L.; Gaspar, A.

2018-04-01

For our sample, we used the systems with a warm component found by Ballering+ (2013, J/ApJ/775/55), where "warm" was defined as warmer than 130K. All of these systems have data available from the Multiband Imaging Photometer for Spitzer (MIPS) at 24 and 70um and from the Spitzer Infrared Spectrograph (IRS). The selected 83 targets used for our analysis are listed in Table 1. (5 data files).

The Infrared Hunter

NASA Image and Video Library

2006-08-15

NASA Spitzer Space Telescope and the National Optical Astronomy Observatory compare infrared and visible views of the famous Orion nebula and its surrounding cloud, an industrious star-making region located near the hunter constellation sword.

VizieR Online Data Catalog: Galactic CHaMP. II. Dense gas clumps. (Ma+, 2013)

NASA Astrophysics Data System (ADS)

Ma, B.; Tan, J. C.; Barnes, P. J.

2015-04-01

A total of 303 dense gas clumps have been detected using the HCO+(1-0) line in the CHaMP survey (Paper I, Barnes et al. 2011, J/ApJS/196/12). In this article we have derived the SED for these clumps using Spitzer, MSX, and IRAS data. The Midcourse Space Experiment (MSX) was launched in 1996 April. It conducted a Galactic plane survey (0

THE MID-INFRARED TULLY-FISHER RELATION: SPITZER SURFACE PHOTOMETRY

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sorce, Jenny G.; Courtois, Helene M.; Tully, R. Brent, E-mail: j.sorce@ipnl.in2p3.fr

2012-11-01

The availability of photometric imaging of several thousand galaxies with the Spitzer Space Telescope enables a mid-infrared calibration of the correlation between luminosity and rotation in spiral galaxies. The most important advantage of the new calibration in the 3.6 {mu}m band, IRAC Channel 1, is photometric consistency across the entire sky. Additional advantages are minimal obscuration, observations of flux dominated by old stars, and sensitivity to low surface brightness levels due to favorable backgrounds. Roughly 3000 galaxies have been observed through Spitzer cycle 7 and images of these are available from the Spitzer archive. In cycle 8, a program calledmore » Cosmic Flows with Spitzer was initiated, which will increase the available sample of spiral galaxies with inclinations greater than 45 Degree-Sign from face-on that are suitable for distance measurements by 1274. This paper describes procedures, based on the photometry package Archangel, that are being employed to analyze both the archival and new data in a uniform way. We give results for 235 galaxies, our calibrator sample for the Tully-Fisher relation. Galaxy magnitudes are determined with uncertainties held below 0.05 mag for normal spiral systems. A subsequent paper will describe the calibration of the [3.6] luminosity-rotation relation.« less

SPRITE: the Spitzer proposal review website

NASA Astrophysics Data System (ADS)

Crane, Megan K.; Storrie-Lombardi, Lisa J.; Silbermann, Nancy A.; Rebull, Luisa M.

2008-07-01

The Spitzer Science Center (SSC), located on the campus of the California Institute of Technology, supports the science operations of NASA's infrared Spitzer Space Telescope. The SSC issues an annual Call for Proposals inviting investigators worldwide to submit Spitzer Space Telescope proposals. The Spitzer Proposal Review Website (SPRITE) is a MySQL/PHP web database application designed to support the SSC proposal review process. Review panel members use the software to view, grade, and write comments about the proposals, and SSC support team members monitor the grading and ranking process and ultimately generate a ranked list of all the proposals. The software is also used to generate, edit, and email award letters to the proposers. This work was performed at the California Institute of Technology under contract to the National Aeronautics and Space Administration.

A Slice of Orion

NASA Technical Reports Server (NTRS)

2006-01-01

[figure removed for brevity, see original site] Extended Orion Nebula Cloud

This image composite shows a part of the Orion constellation surveyed by NASA's Spitzer Space Telescope. The shape of the main image was designed by astronomers to roughly follow the shape of Orion cloud A, an enormous star-making factory containing about 1,800 young stars. This giant cloud includes the famous Orion nebula (bright circular area in 'blade' part of hockey stick-shaped box at the bottom), which is visible to the naked eye on a clear, dark night as a fuzzy star in the hunter constellation's sword.

The region that makes up the shaft part of the hockey stick box stretches 70 light-years beyond the Orion nebula. This particular area does not contain massive young stars like those of the Orion nebula, but is filled with 800 stars about the same mass as the sun. These sun-like stars don't live in big 'cities,' or clusters, of stars like the one in the Orion nebula; instead, they can be found in small clusters (right inset), or in relative isolation (middle insert).

In the right inset, developing stars are illuminating the dusty cloud, creating small wisps that appear greenish. The stars also power speedy jets of gas (also green), which glow as the jets ram into the cloudy material.

Since infrared light can penetrate through dust, we see not only stars within the cloud, but thousands of stars many light-years behind it, which just happen to be in the picture like unwanted bystanders. Astronomers carefully separate the young stars in the Orion cloud complex from the bystanders by looking for their telltale infrared glow.

The infrared image shows light captured by Spitzer's infrared array camera. Light with wavelengths of 8 and 5.8 microns (red and orange) comes mainly from dust that has been heated by starlight. Light of 4.5 microns (green) shows hot gas and dust; and light of 3.6 microns (blue) is from starlight.

The Hidden Galaxy

NASA Image and Video Library

2011-01-18

Maffei 2 is the poster child for an infrared galaxy that is almost invisible to optical telescopes. But this infrared image from NASA Spitzer Space Telescope penetrates the dust to reveal the galaxy in all its glory.

All That Remains of Exploded Star

NASA Image and Video Library

2011-10-24

Infrared images from NASA Spitzer Space Telescope and Wide-field Infrared Survey Explorer are combined in this image of RCW 86, the dusty remains of the oldest documented example of an exploding star, or supernova.

Improving the photometric precision of IRAC Channel 1

NASA Astrophysics Data System (ADS)

Mighell, Kenneth J.; Glaccum, William; Hoffmann, William

2008-07-01

Planning is underway for a possible post-cryogenic mission with the Spitzer Space Telescope. Only Channels 1 and 2 (3.6 and 4.5 μm) of the Infrared Array Camera (IRAC) will be operational; they will have unmatched sensitivity from 3 to 5 microns until the James Webb Space Telescope is launched. At SPIE Orlando, Mighell described his NASA-funded MATPHOT algorithm for precision stellar photometry and astrometry and presented MATPHOT-based simulations that suggested Channel 1 stellar photometry may be significantly improved by modeling the nonuniform RQE within each pixel, which, when not taken into account in aperture photometry, causes the derived flux to vary according to where the centroid falls within a single pixel (the pixel-phase effect). We analyze archival observations of calibration stars and compare the precision of stellar aperture photometry, with the recommended 1-dimensional and a new 2-dimensional pixel-phase aperture-flux correction, and MATPHOT-based PSF-fitting photometry which accounts for the observed loss of stellar flux due to the nonuniform intrapixel quantum efficiency. We show how the precision of aperture photometry of bright isolated stars corrected with the new 2-dimensional aperture-flux correction function can yield photometry that is almost as precise as that produced by PSF-fitting procedures. This timely research effort is intended to enhance the science return not only of observations already in Spitzer data archive but also those that would be made during the Spitzer Warm Mission.

Building the James Webb Space Telescope

NASA Technical Reports Server (NTRS)

Gardner, Jonathan P.

2012-01-01

The James Webb Space Telescope is the scientific successor to the Hubble and Spitzer Space Telescopes. It will be a large (6.6m) cold (50K) telescope launched into orbit around the second Earth-Sun Lagrange point. It is a partnership of NASA with the European and Canadian Space Agencies. JWST will make progress In almost every area of astronomy, from the first galaxies to form in the early universe to exoplanets and Solar System objects. Webb will have four instruments: The Near-Infrared Camera, the Near-Infrared multi-object Spectrograph, and the Near-Infrared Imager and Slitless Spectrograph will cover the wavelength range 0.6 to 5 microns, while the Mid-Infrared Instrument will do both imaging and spectroscopy from 5 to 28.5 microns. The observatory Is confirmed for launch in 2018; the design is complete and it is in its construction phase. Innovations that make JWST possible include large-area low-noise infrared detectors, cryogenic ASICs, a MEMS micro-shutter array providing multi-object spectroscopy, a non-redundant mask for interferometric coronagraphy and diffraction-limited segmented beryllium mirrors with active wavefront sensing and control. Recent progress includes the completion of the mirrors, the delivery of the first flight instruments and the start of the integration and test phase.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jang-Condell, Hannah; Chen, Christine H.; Mittal, Tushar

We analyze spectra obtained with the Spitzer Infrared Spectrograph (IRS) of 110 B-, A-, F-, and G-type stars with optically thin infrared excess in the Scorpius–Centaurus OB association. The ages of these stars range from 11 to 17 Myr. We fit the infrared excesses observed in these sources by Spitzer IRS and the Multiband Imaging Photometer for Spitzer (MIPS) to simple dust models according to Mie theory. We find that nearly all of the objects in our study can be fit by one or two belts of dust. Dust around lower mass stars appears to be closer in than aroundmore » higher mass stars, particularly for the warm dust component in the two-belt systems, suggesting a mass-dependent evolution of debris disks around young stars. For those objects with stellar companions, all dust distances are consistent with truncation of the debris disk by the binary companion. The gaps between several of the two-belt systems can place limits on the planets that might lie between the belts, potentially constraining the mass and locations of planets that may be forming around these stars.« less

Spitzer Sees Water Loud and Clear

NASA Technical Reports Server (NTRS)

2007-01-01

This plot of infrared data, called a spectrum, shows the strong signature of water vapor deep within the core of an embryonic star system, called NGC 1333-IRAS 4B.

The data were captured by NASA's Spitzer Space Telescope using an instrument called a spectrograph. A spectrograph collects light and sorts it according to color, or wavelength. In this case, infrared light from NGC 1333-IRAS 4B was broken up into the wavelengths listed on the horizontal axis of the plot. The sharp spikes, called spectral lines, occur at wavelengths at which the stellar object is particularly bright. The signature of water vapor is revealed in the pattern of wavelengths at which the spikes appear.

By comparing the observed data to a model (lower curve), astronomers can also determine the physical and chemical details of the region. For example, astronomers say these data suggest that ice in a cocoon surrounding the forming star is falling inward. The ice then smacks supersonically into a dusty planet-forming disk surrounding the stellar embryo, heats up and vaporizes quickly, releasing the infrared light that Spitzer collected.

Design of a Teacher-Student Research Program Using the Spitzer Space Telescope

NASA Astrophysics Data System (ADS)

Pompea, S. M.; Daou, D.; Thaller, M.

2004-12-01

Under the sponsorship of the NASA Spitzer Science Center, we have designed a program for teacher and student research using observing time on the Spitzer Space Telescope. The participating teachers attended a fall, 2004 workshop to become familiar with the Spitzer Science Center Archives, observation planning process, and telescope and instrument capabilities in order to plan observations. They also received fundamental training in infrared astronomy and infrared observational techniques, before they began planning their observing program. This program has as its goals the fundamental NASA goals of inspiring and motivating students to pursue careers in science, technology, engineering, and mathematics as well as to engage the public in shaping and sharing the experience of exploration and discovery. Our educational plan addresses the OSS/NASA objectives of improving student proficiency in science and improving science instruction by providing a unique opportunity to a group of teachers and students to observe with the Spitzer Space Telescope and work with infrared archival data. This program allows a team of 12 teachers and their students to utilize up to 3 hours of Director's discretionary observing time on the Spitzer Space Telescope for educational observations. With the goal of leveraging on a well-established teacher professional development, the program serves teachers in the NSF-sponsored Teacher Leaders in Research Based Science Education (TLRRBSE), an ongoing Public Affairs and Educational Outreach Department program at the National Optical Astronomy Observatory (NOAO) in Tucson. The program touches the formal education community through a national audience of well-trained and supported middle and high school teachers. There are currently 68 teachers (and their students) participating in TLRBSE with an additional 57 teachers in the still-supported precursor RBSE program. The Spitzer educational research program also reaches an additional national audience of students through an informal education program based at the University of Arizona's Astronomy Camp, directed by Dr. Don McCarthy, who has been active in both the RBSE and TLRBSE programs. The TLRBSE Project is funded by the National Science Foundation under ESI 0101982, funded through the AURA/NSF Cooperative Agreement AST-9613615. NOAO is operated by the Association of Universities for Research in Astronomy (AURA), Inc. under cooperative agreement with the National Science Foundation. JPL manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology in Pasadena. JPL is a division of Caltech.

VizieR Online Data Catalog: Infrared photometry of all known members in Taurus (Esplin+, 2014)

NASA Astrophysics Data System (ADS)

Esplin, T. L.; Luhman, K. L.; Mamajek, E. E.

2016-08-01

To construct a census of the circumstellar disks in Taurus, we begin by compiling a list of all known members of the region. We adopt the 352 members from Luhman et al. 2010 (cat. J/ApJS/186/111), 4 additional stars that have good evidence of membership from previous studies (Section 5.4), 32 members found in a subsequent survey by K. Luhman (in preparation; 33 if GZ Tau A and B are counted separately), and 25 new members (26 if BS Tau A and B are counted separately) that we have confirmed with spectroscopy (Section 5.3). We also adopt as a member HD 285957, which has a proper motion consistent with that of the Taurus subgroup L1551 (Zacharias et al. 2013, cat. I/322; Luhman et al. 2009ApJ...703..399L) and exhibits evidence of youth in the form of Li absorption (Wichmann et al. 2000A&A...359..181W; Sestito et al. 2008, cat. J/A+A/488/943). We make use of mid-infrared photometry for members of Taurus measured with Spitzer's Infrared Array Camera (IRAC) and the Multiband Imaging Photometer for Spitzer (MIPS). We consider the four bands of IRAC (3.6, 4.5, 5.8, and 8.0μm) and the 24μm band of MIPS, which are denoted as [3.6], [4.5], [5.8], [8.0], and [24], respectively. IRAC produced images with a field of view of 5.2'*5.2' and FWHM of 1.6''-1.9'' for [3.6] to [8.0]. MIPS had a field of view of 5.4'*5.4' and a FWHM of 5.9'' for [24]. Photometry from most Spitzer images for most members of Taurus has been measured by Luhman et al. 2010 (cat. J/ApJS/186/111) (see also Hartmann et al. 2005ApJ...629..881H; Luhman et al. 2006, cat. J/ApJ/647/1180; Guieu et al. 2007, cat. 2007A&A...465..855G; Rebull et al. 2010, cat. J/ApJS/186/259). We have measured photometry of the members that were not considered in Luhman et al. 2010 (cat. J/ApJS/186/111) and all known members appearing in Spitzer images that have become publicly available since that study (Astronomical Observation Requests 26470912, 26471168 26477056, 26475264, 26472704, 26473216, and 23272448). These data were measured with the methods described by Luhman et al. 2010 (cat. J/ApJS/186/111) and are presented in Tables 2 and 3. Members identified after Luhman et al. 2010 (cat. J/ApJS/186/111) that were not detected or observed by Spitzer are not included in these tables. In Table1, we have constructed a compilation of all Spitzer photometry from Luhman et al. 2010 (cat. J/ApJS/186/111) and Tables 2 and 3 for all known members of Taurus. In addition to the Spitzer data, we also utilize the more recent mid-infrared photometry measured by WISE. The four WISE photometric bands are centered at 3.4, 4.6, 12, and 22μm and are denoted as W1 through W4. The first three bands have an angular resolution of ~6'' while W4 has a resolution of ~12''. For unconfused areas near the ecliptic plane, WISE typically achieved a signal-to-noise ratio of 5 at W1=16.8, W2=15.6, W3=11.3, and W4=8.0. To compile the WISE photometry in Taurus, we began by retrieving all sources from the WISE All-Sky Source Catalog (Cutri et al. 2012, cat. II/311) within 2'' of the known members. In total, we report WISE photometry in at least one WISE band for 401 of the entries in Table1. We obtained optical and near-infrared spectra of 10 and 41 WISE candidates, respectively. We also performed infrared spectroscopy on candidate companions to BS Tau and 2MASSJ04485789+2913548. The optical observations were performed with the Marcario Low-Resolution Spectrograph (LRS) on the Hobby-Eberly Telescope (HET) on the nights of 2012 December 5, 8, and 9. The instrument was operated with the G3 grism and the 2'' slit, which provided a wavelength coverage of 6200-9100Å and a resolution of R=1100. The near-infrared spectra were collected with SpeX (Rayner et al. 2003PASP..115..362R) at the NASA Infrared Telescope Facility (IRTF) on the nights of 2012 December 28, 2013 January 1 and 3, and 2013 August 26. The SpeX data were collected in the prism mode with a 0.8'' slit, providing a wavelength coverage of 0.8-2.5μm and a resolution of R=100 for all targets except 2MASS J04221376+1525298, which was observed with the short cross-dispersed (SXD) mode (R=800). Our classifications are presented in Table6. The 34 remaining viable candidates that have not been observed with spectroscopy are presented in Table7. (6 data files).

Understanding Nucleosynthesis in Neutron Star Mergers with Spitzer Observations

NASA Astrophysics Data System (ADS)

Kasliwal, Mansi; Lau, Ryan; Cenko, Brad; Singer, Leo; Goobar, Ariel; Ofek, Eran; Kaplan, David; Andreoni, Igor; Adams, Scott; Perley, Daniel

2018-05-01

The discovery of the first electromagnetic counterpart to gravitational waves from merging neutron stars opened a new chapter in multi-messenger astrophysics. The infrared signature was key to unraveling the prolific production of heavy elements by r-process nucleosynthesis. Understanding the nuclear physics in the heavy element production requires observations a few weeks after the merger at longer wavelengths that are only accessible by Spitzer. In particular, Spitzer can address the question of whether or not the heaviest elements in the third abundance peak (such as gold and platinum) were synthesized. Here, we request 30 hours of Target of Opportunity time to undertake Spitzer follow-up of two neutron star mergers.

Dragonfish Coming At You in Infrared

NASA Image and Video Library

2011-12-12

This infrared image from NASA Spitzer Space Telescope shows the nebula nicknamed the Dragonfish. This turbulent region, jam-packed with stars, is home to some of the most luminous massive stars in our Milky Way galaxy.

Long-Wavelength Infrared Views of Messier 81

NASA Technical Reports Server (NTRS)

2003-01-01

The magnificent and dusty spiral arms of the nearby galaxy Messier 81 are highlighted in these NASA Spitzer Space Telescope images. Located in the northern constellation of Ursa Major (which also includes the Big Dipper), this galaxy is easily visible through binoculars or a small telescope. M81 is located at a distance of 12 million light-years.

The three-panel mosaic is a series of images obtained with the multiband imaging photometer for Spitzer. Thermal infrared emission at 24 microns (top), 70 microns (center) and 160 microns (bottom) is shown in the images. Note that the effective spatial resolution degrades as ones moves to longer wavelengths.

At these wavelengths, Spitzer sees the dust, rather than the stars, within the disc of silicates and carbonaceous grains. It is well-mixed with gas, which is best seen at radio wavelengths, to form the essential ingredients for future star formation.

Cracking the Code of Faraway Worlds

NASA Technical Reports Server (NTRS)

2007-01-01

This infrared data from NASA's Spitzer Space Telescope - called a spectrum - tells astronomers that a distant gas planet, a so-called 'hot Jupiter' called HD 189733b, might be smothered with high clouds. It is one of the first spectra of an alien world.

A spectrum is created when an instrument called a spectrograph cracks light from an object open into a rainbow of different wavelengths. Patterns or ripples within the spectrum indicate the presence, or absence, of molecules making up the object.

Astronomers using Spitzer's spectrograph were able to obtain infrared spectra for two so-called 'transiting' hot-Jupiter planets using the 'secondary eclipse' technique. In this method, the spectrograph first collects the combined infrared light from the planet plus its star, then, as the planet is eclipsed by the star, the infrared light of just the star. Subtracting the latter from the former reveals the planet's own rainbow of infrared colors.

Astronomers were perplexed when they first saw the infrared spectrum above. It doesn't look anything like what theorists had predicted. Theorists thought the spectra of hot, Jupiter-like planets like this one would be filled with the signatures of molecules in the planets' atmospheres. But the spectrum doesn't show any molecules, and is instead what astronomers call 'flat.' For example, theorists thought there'd be a strong signature of water in the form of a big drop in the wavelength range between 7 and 10 microns. The fact that water is not detected may indicate that it is hidden underneath a thick blanket of high, dry clouds. The average brightness of the spectrum is also a bit lower than theoretical predictions, suggesting that very high winds are rapidly moving the terrific heat of the noonday sun from the day side of HD 189733b to the night side.

This spectrum was produced by Dr. Carl Grillmair of NASA's Spitzer Science Center at the California Institute of Technology in Pasadena, Calif., and his colleagues. The data were taken by Spitzer's infrared spectrograph on November 22, 2006.

Cracking the Code of Faraway Worlds

NASA Image and Video Library

2007-02-21

This infrared data from NASA's Spitzer Space Telescope -- called a spectrum -- tells astronomers that a distant gas planet, a so-called "hot Jupiter" called HD 189733b, might be smothered with high clouds. It is one of the first spectra of an alien world. A spectrum is created when an instrument called a spectrograph cracks light from an object open into a rainbow of different wavelengths. Patterns or ripples within the spectrum indicate the presence, or absence, of molecules making up the object. Astronomers using Spitzer's spectrograph were able to obtain infrared spectra for two so-called "transiting" hot-Jupiter planets using the "secondary eclipse" technique. In this method, the spectrograph first collects the combined infrared light from the planet plus its star, then, as the planet is eclipsed by the star, the infrared light of just the star. Subtracting the latter from the former reveals the planet's own rainbow of infrared colors. Astronomers were perplexed when they first saw the infrared spectrum above. It doesn't look anything like what theorists had predicted. Theorists thought the spectra of hot, Jupiter-like planets like this one would be filled with the signatures of molecules in the planets' atmospheres. But the spectrum doesn't show any molecules, and is instead what astronomers call "flat." For example, theorists thought there'd be a strong signature of water in the form of a big drop in the wavelength range between 7 and 10 microns. The fact that water is not detected may indicate that it is hidden underneath a thick blanket of high, dry clouds. The average brightness of the spectrum is also a bit lower than theoretical predictions, suggesting that very high winds are rapidly moving the terrific heat of the noonday sun from the day side of HD 189733b to the night side. This spectrum was produced by Dr. Carl Grillmair of NASA's Spitzer Science Center at the California Institute of Technology in Pasadena, Calif., and his colleagues. The data were taken by Spitzer's infrared spectrograph on November 22, 2006. http://photojournal.jpl.nasa.gov/catalog/PIA09199

Featured Image: A Molecular Cloud Outside Our Galaxy

NASA Astrophysics Data System (ADS)

Kohler, Susanna

2018-06-01

What do molecular clouds look like outside of our own galaxy? See for yourself in the images above and below of N55, a molecular cloud located in the Large Magellanic Cloud (LMC). In a recent study led by Naslim Neelamkodan (Academia Sinica Institute of Astronomy and Astrophysics, Taiwan), a team of scientists explore N55 to determine how its cloud properties differ from clouds within the Milky Way. The image above reveals the distribution of infrared-emitting gas and dust observed in three bands by the Spitzer Space Telescope. Overplotted in cyan are observations from the Atacama Submillimeter Telescope Experiment tracing the clumpy, warm molecular gas. Below, new observations from the Atacama Large Millimeter/submillimeter Array (ALMA) reveal the sub-parsec-scale molecular clumps in greater detail, showing the correlation of massive clumps with Spitzer-identified young stellar objects (crosses). The study presented here indicates that this cloud in the LMC is the site of massive star formation, with properties similar to equivalent clouds in the Milky Way. To learn more about the authors findings, check out the article linked below.CitationNaslim N. et al 2018 ApJ 853 175. doi:10.3847/1538-4357/aaa5b0

An Integrated Optimal Estimation Approach to Spitzer Space Telescope Focal Plane Survey

NASA Technical Reports Server (NTRS)

Bayard, David S.; Kang, Bryan H.; Brugarolas, Paul B.; Boussalis, D.

2004-01-01

This paper discusses an accurate and efficient method for focal plane survey that was used for the Spitzer Space Telescope. The approach is based on using a high-order 37-state Instrument Pointing Frame (IPF) Kalman filter that combines both engineering parameters and science parameters into a single filter formulation. In this approach, engineering parameters such as pointing alignments, thermomechanical drift and gyro drifts are estimated along with science parameters such as plate scales and optical distortions. This integrated approach has many advantages compared to estimating the engineering and science parameters separately. The resulting focal plane survey approach is applicable to a diverse range of science instruments such as imaging cameras, spectroscopy slits, and scanning-type arrays alike. The paper will summarize results from applying the IPF Kalman Filter to calibrating the Spitzer Space Telescope focal plane, containing the MIPS, IRAC, and the IRS science Instrument arrays.

Infrared Astronomy Professional Development for K-12 Educators: WISE Telescope

NASA Astrophysics Data System (ADS)

Borders, Kareen; Mendez, B. M.

2010-01-01

K-12 educators need effective and relevant astronomy professional development. WISE Telescope (Wide-Field Infrared Survey Explorer) and Spitzer Space Telescope Education programs provided an immersive teacher professional development workshop at Arecibo Observatory in Puerto Rico during the summer of 2009. As many common misconceptions involve scale and distance, teachers worked with Moon/Earth scale, solar system scale, and distance of objects in the universe. Teachers built and used basic telescopes, learned about the history of telescopes, explored ground and satellite based telescopes, and explored and worked on models of WISE Telescope. An in-depth explanation of WISE and Spitzer telescopes gave participants background knowledge for infrared astronomy observations. We taught the electromagnetic spectrum through interactive stations. The stations included an overview via lecture and power point, the use of ultraviolet beads to determine ultraviolet exposure, the study of WISE lenticulars and diagramming of infrared data, listening to light by using speakers hooked up to photoreceptor cells, looking at visible light through diffraction glasses and diagramming the data, protocols for using astronomy based research in the classroom, and infrared thermometers to compare environmental conditions around the observatory. An overview of LIDAR physics was followed up by a simulated LIDAR mapping of the topography of Mars. We will outline specific steps for K-12 infrared astronomy professional development, provide data demonstrating the impact of the above professional development on educator understanding and classroom use, and detail future plans for additional K-12 professional development. Funding was provided by WISE Telescope, Spitzer Space Telescope, Starbucks, Arecibo Observatory, the American Institute of Aeronautics and Astronautics, and the Washington Space Grant Consortium.

Spitzer Telescope Sends Rose for Valentine Day

NASA Image and Video Library

2004-02-12

A cluster of newborn stars herald their birth in this interstellar Valentine Day commemorative picture obtained with NASA Spitzer Space Telescope. These bright young stars are found in a rosebud-shaped and rose-colored nebulosity known as NGC 7129. The star cluster and its associated nebula are located at a distance of 3300 light-years in the constellation Cepheus. A recent census of the cluster reveals the presence of 130 young stars. The stars formed from a massive cloud of gas and dust that contains enough raw materials to create a thousand Sun-like stars. In a process that astronomers still poorly understand, fragments of this molecular cloud became so cold and dense that they collapsed into stars. Most stars in our Milky Way galaxy are thought to form in such clusters. The Spitzer Space Telescope image was obtained with an infrared array camera that is sensitive to invisible infrared light at wavelengths that are about ten times longer than visible light. In this four-color composite, emission at 3.6 microns is depicted in blue, 4.5 microns in green, 5.8 microns in orange, and 8.0 microns in red. The image covers a region that is about one quarter the size of the full moon. As in any nursery, mayhem reigns. Within the astronomically brief period of a million years, the stars have managed to blow a large, irregular bubble in the molecular cloud that once enveloped them like a cocoon. The rosy pink hue is produced by glowing dust grains on the surface of the bubble being heated by the intense light from the embedded young stars. Upon absorbing ultraviolet and visible-light photons produced by the stars, the surrounding dust grains are heated and re-emit the energy at the longer infrared wavelengths observed by Spitzer. The reddish colors trace the distribution of molecular material thought to be rich in hydrocarbons. The cold molecular cloud outside the bubble is mostly invisible in these images. However, three very young stars near the center of the image are sending jets of supersonic gas into the cloud. The impact of these jets heats molecules of carbon monoxide in the cloud, producing the intricate green nebulosity that forms the stem of the rosebud. Not all stars are formed in clusters. Away from the main nebula and its young cluster are two smaller nebulae, to the left and bottom of the central 'rosebud,'each containing a stellar nursery with only a few young stars. Astronomers believe that our own Sun may have formed billions of years ago in a cluster similar to NGC 7129. Once the radiation from new cluster stars destroys the surrounding placental material, the stars begin to slowly drift apart. http://photojournal.jpl.nasa.gov/catalog/PIA05266

An empirical mass-loss law for Population II giants from the Spitzer-IRAC survey of Galactic globular clusters

NASA Astrophysics Data System (ADS)

Origlia, L.; Ferraro, F. R.; Fabbri, S.; Fusi Pecci, F.; Dalessandro, E.; Rich, R. M.; Valenti, E.

2014-04-01

Aims: The main aim of the present work is to derive an empirical mass-loss (ML) law for Population II stars in first and second ascent red giant branches. Methods: We used the Spitzer InfraRed Array Camera (IRAC) photometry obtained in the 3.6-8 μm range of a carefully chosen sample of 15 Galactic globular clusters spanning the entire metallicity range and sampling the vast zoology of horizontal branch (HB) morphologies. We complemented the IRAC photometry with near-infrared data to build suitable color-magnitude and color-color diagrams and identify mass-losing giant stars. Results: We find that while the majority of stars show colors typical of cool giants, some stars show an excess of mid-infrared light that is larger than expected from their photospheric emission and that is plausibly due to dust formation in mass flowing from them. For these stars, we estimate dust and total (gas + dust) ML rates and timescales. We finally calibrate an empirical ML law for Population II red and asymptotic giant branch stars with varying metallicity. We find that at a given red giant branch luminosity only a fraction of the stars are losing mass. From this, we conclude that ML is episodic and is active only a fraction of the time, which we define as the duty cycle. The fraction of mass-losing stars increases by increasing the stellar luminosity and metallicity. The ML rate, as estimated from reasonable assumptions for the gas-to-dust ratio and expansion velocity, depends on metallicity and slowly increases with decreasing metallicity. In contrast, the duty cycle increases with increasing metallicity, with the net result that total ML increases moderately with increasing metallicity, about 0.1 M⊙ every dex in [Fe/H]. For Population II asymptotic giant branch stars, we estimate a total ML of ≤0.1 M⊙, nearly constant with varying metallicity. This work is based on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with NASA. Support for this work was provided by NASA through an award issued by JPL/Caltech.Appendix A is available in electronic form at http://www.aanda.org

Spitzer/IRS spectroscopy of the 12um Seyferts

NASA Astrophysics Data System (ADS)

Wu, Yanling; Charmandaris, V.; Huang, J.; Houck, J.

2009-01-01

The extended 12um galaxy sample is a flux-limited sample of 893 galaxies selected from the IRAS Faint Source Catalog 2. A total of 118 objects from this sample have been classified optically as Seyfert galaxies, providing one of the largest infrared selected unbiased sample of active galactic nuclei (AGN). We present our prelimary results from our analysis of mid-infrared Spitzer/IRS spectra of 102 12um Seyferts (that is 86 % of the 12um Seyfert sample) which have been observed by various Spitzer programs and are available in the Spitzer archive. A number of mid-infared diagnostics have been developed to study the nature of nuclear dust enshrouded emission from AGNs, in order to disentangle the starburst-AGN connection. Since PAH emission is a tracer of star formation activity we have measured the 11.3um PAH feature for our Seyfert sample. We find that as the strength of the radiation field in AGNs increases the PAH molecules are destroyed, while the PAH EWs increase with the IRAS f60/f25 ratios of the host galaxies. We further probe this warm/cold color diagnostic, by contrasting our findings with those of we starbust galaxies, ULIRGs, as well as blue compact dwarf galaxies.

A Twisted Star-Forming Web in the Galaxy IC 342

NASA Image and Video Library

2011-07-20

Looking like a spider web swirled into a spiral, galaxy IC 342 presents its delicate pattern of dust in this infrared light image from NASA Spitzer Space Telescope. The very center glows especially brightly in the infrared.

First Stars or Stray Stars? A Cosmic Infrared Mystery

NASA Image and Video Library

2014-11-06

Our sky is filled with a diffuse background glow, known as the cosmic infrared background. Much of the light is from galaxies we know about, but previous Spitzer measurements have shown an extra component of unknown origin.

The AKARI FU-HYU galaxy evolution program: first results from the GOODS-N field

NASA Astrophysics Data System (ADS)

Pearson, C. P.; Serjeant, S.; Negrello, M.; Takagi, T.; Jeong, W.-S.; Matsuhara, H.; Wada, T.; Oyabu, S.; Lee, H. M.; Im, M. S.

2010-05-01

The AKARI FU-HYU mission program carried out mid-infrared imaging of several well studied Spitzer fields preferentially selecting fields already rich in multi-wavelength data from radio to X-ray wavelengths filling in the wavelength desert between the Spitzer IRAC and MIPS bands. We present the initial results for the FU-HYU survey in the GOODS-N field. We utilize the supreme multiwavelength coverage in the GOODS-N field to produce a multiwavelength catalogue from infrared to ultraviolet wavelengths, containing more than 4393 sources, including photometric redshifts. Using the FU-HYU catalogue we present colour-colour diagrams that map the passage of PAH features through our observation bands. We find that the longer mid-infrared bands from AKARI (IRC-L18W 18 micron band) and Spitzer (MIPS24 24 micron band) provide an accurate measure of the total MIR emission of the sources and therefore their probable total mid-infrared luminosity. We also find that colours incorporating the AKARI IRC-S11 11 micron band produce a bimodal distribution where an excess at 11 microns preferentially selects moderate redshift star-forming galaxies. These powerful colour-colour diagnostics are further used as tools to extract anomalous colour populations, in particular a population of Silicate Break galaxies from the GOODS-N field showing that dusty starbursts can be selected of specific redshift ranges (z = 1.2-1.6) by mid-infrared drop-out techniques. The FU-HYU catalogue will be made publically available to the astronomical community.

THE SPITZER-WISE SURVEY OF THE ECLIPTIC POLES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jarrett, T. H.; Masci, F.; Cutri, R. M.

2011-07-10

We have carried out a survey of the north and south ecliptic poles, EP-N and EP-S, respectively, with the Spitzer Space Telescope and the Wide-field Infrared Survey Explorer (WISE). The primary objective was to cross-calibrate WISE with the Spitzer and Midcourse Space Experiment (MSX) photometric systems by developing a set of calibration stars that are common to these infrared missions. The ecliptic poles were continuous viewing zones for WISE due to its polar-crossing orbit, making these areas ideal for both absolute and internal calibrations. The Spitzer IRAC and MIPS imaging survey covers a complete area of 0.40 deg{sup 2} formore » the EP-N and 1.28 deg{sup 2} for the EP-S. WISE observed the whole sky in four mid-infrared bands, 3.4, 4.6, 12, and 22 {mu}m, during its eight-month cryogenic mission, including several hundred ecliptic polar passages; here we report on the highest coverage depths achieved by WISE, an area of {approx}1.5 deg{sup 2} for both poles. Located close to the center of the EP-N, the Sy-2 galaxy NGC 6552 conveniently functions as a standard calibrator to measure the red response of the 22 {mu}m channel of WISE. Observations from Spitzer-IRAC/MIPS/IRS-LL and WISE show that the galaxy has a strong red color in the mid-infrared due to star-formation and the presence of an active galactic nucleus (AGN), while over a baseline >1 year the mid-IR photometry of NGC 6552 is shown to vary at a level less than 2%. Combining NGC 6552 with the standard calibrator stars, the achieved photometric accuracy of the WISE calibration, relative to the Spitzer and MSX systems, is 2.4%, 2.8%, 4.5%, and 5.7% for W1 (3.4 {mu}m), W2 (4.6 {mu}m), W3 (12 {mu}m), and W4 (22 {mu}m), respectively. The WISE photometry is internally stable to better than 0.1% over the cryogenic lifetime of the mission. The secondary objective of the Spitzer-WISE Survey was to explore the poles at greater flux-level depths, exploiting the higher angular resolution Spitzer observations and the exceptionally deep (in total coverage) WISE observations that potentially reach down to the confusion limit of the survey. The rich Spitzer and WISE data sets were used to study the Galactic and extragalactic populations through source counts, color-magnitude and color-color diagrams. As an example of what the data sets facilitate, we have separated stars from galaxies, delineated normal galaxies from power-law-dominated AGNs, and reported on the different fractions of extragalactic populations. In the EP-N, we find an AGN source density of {approx}260 deg{sup -2} to a 12 {mu}m depth of 115 {mu}Jy, representing 15% of the total extragalactic population to this depth, similar to what has been observed for low-luminosity AGNs in other fields.« less

Polycyclic Aromatic Hydrocarbons and Infrared Astrophysics with Spitzer

NASA Technical Reports Server (NTRS)

Allamandola, L. J.; Hudgins, D. M.

2004-01-01

PAH spectral features are now being used as new probes of the ISM. PAH ionization states reflect the ionization balance of the medium while PAH size and structure reflect the energetic and chemical history of the medium. This paper will focus on recent applications of the NASA Ames PAH IR spectral Database to interpret astronomical observations made by the Spitzer Space telescope and other space based infrared instruments. Examples will be given showing how changes in the spectral characteristics of different objects reveal interstellar PAH characteristics such as structure, size and composition, as well as provide insight into the chemical history and physical nature of the emission zones.

Elemental Abundances of Blue Compact Dwarfs from Mid-Infrared Spectroscopy with Spitzer

NASA Astrophysics Data System (ADS)

Wu, Yanling; Bernard-Salas, J.; Charmandaris, V.; Lebouteiller, V.; Hao, Lei; Brandl, B. R.; Houck, J. R.

2008-01-01

We present a study of elemental abundances in a sample of 13 blue compact dwarf (BCD) galaxies, using the ~10-37 μm high-resolution spectra obtained with Spitzer IRS. We derive the abundances of neon and sulfur for our sample using the infrared fine-structure lines probing regions which may be obscured by dust in the optical and compare our results with similar infrared studies of starburst galaxies from ISO. We find a good correlation between the neon and sulfur abundances, although sulfur is underabundant relative to neon with respect to the solar value. A comparison of the elemental abundances (neon and sulfur) measured from the infrared data with those derived from the optical (neon, sulfur, and oxygen) studies reveals a good overall agreement for sulfur, while the infrared-derived neon abundances are slightly higher than the optical values. This indicates either that the metallicities of dust-enshrouded regions in BCDs are similar to the optically accessible regions, or that if they are different they do not contribute substantially to the total infrared emission of the host galaxy.

Archival Investigation of Outburst Sites and Progenitors of Extragalactic Intermediate-Luminosity Mid-IR Transients

NASA Astrophysics Data System (ADS)

Bond, Howard

2017-08-01

Our team is using Spitzer in a long-term search for extragalactic mid-infrared (MIR) variable stars and transients-the SPIRITS project (SPitzer InfraRed Intensive Transients Survey). In this first exploration of luminous astrophysical transients in the infrared, we have discovered a puzzling new class. We call them SPRITEs: eSPecially Red Intermediate-luminosity Transient Events. They have maximum MIR luminosities between supernovae and classical novae, but are not detected in the optical to deep limits. To date, we have discovered more than 50 SPRITEs in galaxies out to 17 Mpc. In this Archival Research proposal, we request support in order to investigate the pre-eruption sites in HST images of some 3 dozen SPRITEs discovered to date, and an additional 2 dozen that we are likely to find until the end of Spitzer observing in late 2018. Our aims are (1) characterize the pre-outburst environments at HST resolution in the visible and near-IR, to understand the stellar populations, stellar ages and masses, and interstellar medium at the outburst sites; (2) search for progenitors; (3) help prepare the way for a better understanding of the nature of extragalactic IR transients that will be investigated by JWST.

Spitzer Observations of the New Luminous Red Nova M85 OT2006-1

NASA Astrophysics Data System (ADS)

Rau, A.; Kulkarni, S. R.; Ofek, E. O.; Yan, L.

2007-04-01

M85 OT2006-1 is the latest and most brilliant addition to the small group of known luminous red novae (LRNe). An identifying characteristic of the previously detected events (M31 RV, V4332 Sgr, and V838 Mon) was a spectral redward evolution connected with an emerging infrared component following the optical decay. Here we report on the discovery of a similar feature in Keck NIRC and Spitzer photometry of M85 OT2006-1 6 months posteruption. We find that its 2.1-22 μm spectral energy distribution is best described by a blackbody with effective temperature Teff=950+/-150 K and bolometric luminosity L=2.9+0.4-0.5×105 Lsolar. Assuming spherical geometry, the blackbody effective radius, R=2.0+0.6-0.4×104 Rsolar, and corresponding expansion velocity, v=870+260-180 km s-1, are remarkably similar to the properties of M31 RV 70 days after its eruption. Furthermore, we propose a search strategy for LRNe in the local universe making use of the longevity of their infrared excess emission and discuss the expected number of events in the Spitzer Infrared Nearby Galaxies Survey.

The Clustering of High-Redshift (2.9 < z < 5.4) Quasars in SDSS Stripe 82

NASA Astrophysics Data System (ADS)

Timlin, John; Ross, Nicolas; Richards, Gordon; Myers, Adam; Bauer, Franz Erik; Lacy, Mark; Schneider, Donald; Wollack, Edward; Zakamska, Nadia

2018-01-01

We present the data from the Spitzer IRAC Equatorial Survey (SpIES) along with our first high-redshift (2.9

VizieR Online Data Catalog: Tori in AGNs through Spitzer/IRS spectra (Gonzalez-Martin+, 2017)

NASA Astrophysics Data System (ADS)

Gonzalez-Martin, O.; Masegosa, J.; Hernan-Caballero, A.; Marquez, I.; Almeida, C. R.; Alonso-Herrero, A.; Aretxaga, I.; Rodriguez-Espinosa, J. M.; Acosta-Pulido, J. A.; Hernandez-Garcia, L.; Esparza-Arredondo, D.; Martinez-Paredes, M.; Bonfini, P.; Pasetto, A.; Dultzin, D.

2018-01-01

The sample was originally presented by Gonzalez-Martin+ (2015, J/A+A/578/A74). The LINER sample is selected as those objects with reported X-ray luminosities from Gonzalez-Martin+ (2009A&A...506.1107G) with full coverage of the 5-30um range with the InfraRed Spectrograph (Spitzer/IRS) spectra. This guarantees that all of the LINERs have LX(2-10keV) measurements. Among the 48 LINERs with Spitzer/IRS spectra, 40 mid-infrared spectra were taken from the CASSIS atlas (Lebouteiller+ 2011ApJS..196....8L) and 8 from the SINGS database (Kennicutt+ 2003PASP..115..928K). We have included in our analysis mid-infrared spatially resolved images taken with CanariCam/GTC using the filter "Si6" centered at 11.5um. These observations are part of proprietary data of a sample of faint and Compton-thick LINERs observed with CanariCam/GTC (proposal ID GTC10-14A, P.I. Gonzalez-Martin). The summary of the observations used in this paper is reported in Table 4. See section 3.2 for further explanations. (5 data files).

The Last Gasp of Gas Giant Planet Formation: A Spitzer Study of the 5 Myr Old Cluster NGC 2362

NASA Astrophysics Data System (ADS)

Currie, Thayne; Lada, Charles J.; Plavchan, Peter; Robitaille, Thomas P.; Irwin, Jonathan; Kenyon, Scott J.

2009-06-01

Expanding upon the Infrared Array Camera (IRAC) survey from Dahm & Hillenbrand, we describe Spitzer IRAC and Multiband Imaging Photometer for Spitzer observations of the populous, 5 Myr old open cluster NGC 2362. We analyze the mid-IR colors of cluster members and compared their spectral energy distributions (SEDs) to star+circumstellar disk models to constrain the disk morphologies and evolutionary states. Early/intermediate-type confirmed/candidate cluster members either have photospheric mid-IR emission or weak, optically thin IR excess emission at λ >= 24 μm consistent with debris disks. Few late-type, solar/subsolar-mass stars have primordial disks. The disk population around late-type stars is dominated by disks with inner holes (canonical "transition disks") and "homologously depleted" disks. Both types of disks represent an intermediate stage between primordial disks and debris disks. Thus, in agreement with previous results, we find that multiple paths for the primordial-to-debris disk transition exist. Because these "evolved primordial disks" greatly outnumber primordial disks, our results undermine standard arguments in favor of a lsim105 yr timescale for the transition based on data from Taurus-Auriga. Because the typical transition timescale is far longer than 105 yr, these data also appear to rule out standard ultraviolet photoevaporation scenarios as the primary mechanism to explain the transition. Combining our data with other Spitzer surveys, we investigate the evolution of debris disks around high/intermediate-mass stars and investigate timescales for giant planet formation. Consistent with Currie et al., the luminosity of 24 μm emission in debris disks due to planet formation peaks at ≈10-20 Myr. If the gas and dust in disks evolve on similar timescales, the formation timescale for gas giant planets surrounding early-type, high/intermediate-mass (gsim1.4 M sun) stars is likely 1-5 Myr. Most solar/subsolar-mass stars detected by Spitzer have SEDs that indicate their disks may be actively leaving the primordial disk phase. Thus, gas giant planet formation may also occur by ~5 Myr around solar/subsolar-mass stars as well.

New z>2 clusters unveiled by Planck, Herschel & Spitzer - prospects for JWST & Euclid

NASA Astrophysics Data System (ADS)

Dole, Herve A.

2015-08-01

Searching for z>2 clusters/protoclusters is an active field in cosmology, and quite successfull using wide near-infrared surveys (e.g. Spitzer). We present a new approach by selecting highly star forming high-z cluster candidates over the whole sky using Planck, taking benefit of the redshifted far-infrared peak into the Planck submillimetre channels and a clean component separation (among which Galactic cirrus & CMB). Out of more than 1000 Planck high-z candidates, about 230 were confirmed by a Herschel/SPIRE follow-up as significant overdensities of red sources, confirming their high-z spectral energy distribution and high star formation rates (typically 700 Msun/yr per SPIRE source, and >5000 Msun/yr for each structure). These overdensities could be protoclusters in their intense star formation phase. Few targets have spectroscopic redshift (in the NIR and mm) confirmations, all in the range 1.7-2.3, while photometric analysis indicates z>2 for all the Planck counterparts.The key points here are the wavelength plus the angular and resolution coverage from Planck, Herschel and Spitzer. 40 fields were followed-up by Spitzer down to 1uJy 5sigma, and show unambiguous presence of galaxy overdensities compatible with z~2 based on color analysis on 4 band photometry (J, K, 3.6 and 4.5um). These targetted Spitzer observations can serve as pilot project for the more extended data coming in the next decade with JWST and Euclid.This new window on the high-z (z>2) protocluster may yield powerful constraints on structure formation (e.g., SFR vs environnement at high-z, z>2 mass assembly in clusters, bias). Furthermore, these objects will allow to better quantify the prediction for clusters to be detected by WFIRST and Euclid. Finally, these clusters will help us extending the current search for high-z clusters, in nice complementarity with current selections in the near-infrared (dominated by stellar mass) and the millimeter (dominated by hot gas and SZ effect), using the far-infrared and submillimetre (dominated by star formation). My talk will review all these aspects.

New z>2 clusters unveiled by Planck, Herschel & Spitzer - prospects for JWST, Euclid, WFIRST

NASA Astrophysics Data System (ADS)

Dole, Herve A.

2015-08-01

Searching for z>2 clusters/protoclusters is an active field in cosmology, and quite successfull using wide near-infrared surveys (e.g. Spitzer). We present a new approach by selecting highly star forming high-z cluster candidates over the whole sky using Planck, taking benefit of the redshifted far-infrared peak into the Planck submillimetre channels and a clean component separation (among which Galactic cirrus & CMB). Out of more than 1000 Planck high-z candidates, about 230 were confirmed by a Herschel/SPIRE follow-up as significant overdensities of red sources, confirming their high-z spectral energy distribution and high star formation rates (typically 700 Msun/yr per SPIRE source, and >5000 Msun/yr for each structure). These overdensities could be protoclusters in their intense star formation phase. Few targets have spectroscopic redshift (in the NIR and mm) confirmations, all in the range 1.7-2.3, while photometric analysis indicates z>2 for all the Planck counterparts.The key points here are the wavelength plus the angular and resolution coverage from Planck, Herschel and Spitzer. 40 fields were followed-up by Spitzer down to 1uJy 5sigma, and show unambiguous presence of galaxy overdensities compatible with z~2 based on color analysis on 4 band photometry (J, K, 3.6 and 4.5um). These targetted Spitzer observations can serve as pilot project for the more extended data coming in the next decade with JWST and Euclid.This new window on the high-z (z>2) protocluster may yield powerful constraints on structure formation (e.g., SFR vs environnement at high-z, z>2 mass assembly in clusters, bias). Furthermore, these objects will allow to better quantify the prediction for clusters to be detected by WFIRST and Euclid. Finally, these clusters will help us extending the current search for high-z clusters, in nice complementarity with current selections in the near-infrared (dominated by stellar mass) and the millimeter (dominated by hot gas and SZ effect), using the far-infrared and submillimetre (dominated by star formation). My talk will review all these aspects.

Unmasking a Hidden Glow

NASA Image and Video Library

2012-10-24

The image on the left shows a portion of our sky, called the Boötes field, in infrared light, while the image on the right shows a mysterious, background infrared glow captured by NASA Spitzer Space Telescope in the same region of sky.

Hot and Cold in the M100 Galaxy

NASA Image and Video Library

2012-08-15

The galaxy Messier 100, or M100, shows its swirling spiral in this infrared image from NASA Spitzer Space Telescope. The arcing spiral arms of dust and gas that harbor star forming regions glow vividly when seen in the infrared.

Repeatability and Accuracy of Exoplanet Eclipse Depths Measured with Post-cryogenic Spitzer

NASA Astrophysics Data System (ADS)

Ingalls, James G.; Krick, J. E.; Carey, S. J.; Stauffer, John R.; Lowrance, Patrick J.; Grillmair, Carl J.; Buzasi, Derek; Deming, Drake; Diamond-Lowe, Hannah; Evans, Thomas M.; Morello, G.; Stevenson, Kevin B.; Wong, Ian; Capak, Peter; Glaccum, William; Laine, Seppo; Surace, Jason; Storrie-Lombardi, Lisa

2016-08-01

We examine the repeatability, reliability, and accuracy of differential exoplanet eclipse depth measurements made using the InfraRed Array Camera (IRAC) on the Spitzer Space Telescope during the post-cryogenic mission. We have re-analyzed an existing 4.5 μm data set, consisting of 10 observations of the XO-3b system during secondary eclipse, using seven different techniques for removing correlated noise. We find that, on average, for a given technique, the eclipse depth estimate is repeatable from epoch to epoch to within 156 parts per million (ppm). Most techniques derive eclipse depths that do not vary by more than a factor 3 of the photon noise limit. All methods but one accurately assess their own errors: for these methods, the individual measurement uncertainties are comparable to the scatter in eclipse depths over the 10 epoch sample. To assess the accuracy of the techniques as well as to clarify the difference between instrumental and other sources of measurement error, we have also analyzed a simulated data set of 10 visits to XO-3b, for which the eclipse depth is known. We find that three of the methods (BLISS mapping, Pixel Level Decorrelation, and Independent Component Analysis) obtain results that are within three times the photon limit of the true eclipse depth. When averaged over the 10 epoch ensemble, 5 out of 7 techniques come within 60 ppm of the true value. Spitzer exoplanet data, if obtained following current best practices and reduced using methods such as those described here, can measure repeatable and accurate single eclipse depths, with close to photon-limited results.

Bruce Grossan's Home Page

Science.gov Websites

Generation Rapid-Optical Response GRB Mission (ADS link) now on web (i.e. arxiv link). First Spitzer Paper the Infra-Red (2.1 micron K' band), taken at the Wyoming IR Observatory (WIRO) 4/16/94. The galaxy is largest, most sensitive map of a low-dust region made with the Spitzer 160 µm Camera. The cosmic far-IR

DOE Office of Scientific and Technical Information (OSTI.GOV)

Papovich, C.; Shipley, H. V.; Mehrtens, N.

We present post-cryogenic Spitzer imaging at 3.6 and 4.5 μ m with the Infrared Array Camera (IRAC) of the Spitzer /HETDEX Exploratory Large-Area (SHELA) survey. SHELA covers ≈24 deg{sup 2} of the Sloan Digital Sky Survey “Stripe 82” region, and falls within the footprints of the Hobby–Eberly Telescope Dark Energy Experiment (HETDEX) and the Dark Energy Survey. The HETDEX blind R ∼ 800 spectroscopy will produce ∼200,000 redshifts from the Ly α emission for galaxies in the range 1.9 <  z  < 3.5, and an additional ∼200,000 redshifts from the [O ii] emission for galaxies at z  < 0.5. When combined with deepmore » ugriz images from the Dark Energy Camera, K -band images from NEWFIRM, and other ancillary data, the IRAC photometry from Spitzer will enable a broad range of scientific studies of the relationship between structure formation, galaxy stellar mass, halo mass, the presence of active galactic nuclei, and environment over a co-moving volume of ∼0.5 Gpc{sup 3} at 1.9 <  z  < 3.5. Here, we discuss the properties of the SHELA IRAC data set, including the data acquisition, reduction, validation, and source catalogs. Our tests show that the images and catalogs are 80% (50%) complete to limiting magnitudes of 22.0 (22.6) AB mag in the detection image, which is constructed from the weighted sum of the IRAC 3.6 and 4.5 μ m images. The catalogs reach limiting sensitivities of 1.1  μ Jy at both 3.6 and 4.5 μ m (1 σ , for R = 2″ circular apertures). As a demonstration of the science, we present IRAC number counts, examples of highly temporally variable sources, and galaxy surface density profiles of rich galaxy clusters. In the spirit of the Spitzer Exploratory programs, we provide all of the images and catalogs as part of the publication.« less

VizieR Online Data Catalog: YSOs search in LDN 1340 in optical (Kun+, 2016)

NASA Astrophysics Data System (ADS)

Kun, M.; Moor, A.; Szegedi-Elek, E.; Reipurth, B.

2016-08-01

We observed the optical spectra of 23 stars, utilizing several instruments, namely CAFOS with the G-100 grism, installed on the 2.2m telescope of the Calar Alto Observatory, FAST on the 1.5m telescope of the Fred Lawrence Whipple Observatory, ALFOSC with grism 8 on the Nordic Optical Telescope in the Observatorio del Roque de los Muchachos in La Palma, and the low-resolution slit spectrograph operated on the 1m RCC telescope of the Konkoly Observatory between 1999 Aug 07 and 2011 Sep 27 (see table 1). We observed L1340 with the Wide Field Grism Spectrograph 2 (WFGS2), installed on the University of Hawaii 2.2m telescope, on 2011 January 1, October 15, 16, and 18, and 2012 August 10. We covered an area of 30x40arcmin, centered on RA=2:30,DE=72:48(J2000), with a mosaic of 12 overlapping fields. We found 75 stars with Hα emission by examining the images visually. See section 2.2 and table 2. Spitzer L1340 was observed by the Spitzer Space Telescope using Spitzer's Infrared Array Camera (IRAC) on 2009 March 16 and by the Multiband Imaging Photometer for Spitzer (MIPS) on 2008 November 26 (Prog. ID: 50691, PI: G. Fazio). A small part of the cloud, centered on RNO 7, was observed in the four IRAC bands on 2006 September 24 (Prog. ID: 30734, PI: D. Figer). All but eight of the Hα sources have counterparts in the AllWISE Source Catalog (Wright et al. 2010AJ....140.1868W; see II/328). L1340 is situated within Stripe 1260 of the SEGUE survey (Yanny et al. 2009, J/AJ/137/4377). Each of our target stars has a counterpart in the SDSS Data Release 9 (Ahn et al. 2012, V/139) within 1" of the 2MASS position. (6 data files).

SPITZER SECONDARY ECLIPSE DEPTHS WITH MULTIPLE INTRAPIXEL SENSITIVITY CORRECTION METHODS OBSERVATIONS OF WASP-13b, WASP-15b, WASP-16b, WASP-62b, AND HAT-P-22b

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kilpatrick, Brian M.; Tucker, Gregory S.; Lewis, Nikole K.

2017-01-01

We measure the 4.5 μ m thermal emission of five transiting hot Jupiters, WASP-13b, WASP-15b, WASP-16b, WASP-62b, and HAT-P-22b using channel 2 of the Infrared Array Camera (IRAC) on the Spitzer Space Telescope . Significant intrapixel sensitivity variations in Spitzer IRAC data require careful correction in order to achieve precision on the order of several hundred parts per million (ppm) for the measurement of exoplanet secondary eclipses. We determine eclipse depths by first correcting the raw data using three independent data reduction methods. The Pixel Gain Map (PMAP), Nearest Neighbors (NNBR), and Pixel Level Decorrelation (PLD) each correct for themore » intrapixel sensitivity effect in Spitzer photometric time-series observations. The results from each methodology are compared against each other to establish if they reach a statistically equivalent result in every case and to evaluate their ability to minimize uncertainty in the measurement. We find that all three methods produce reliable results. For every planet examined here NNBR and PLD produce results that are in statistical agreement. However, the PMAP method appears to produce results in slight disagreement in cases where the stellar centroid is not kept consistently on the most well characterized area of the detector. We evaluate the ability of each method to reduce the scatter in the residuals as well as in the correlated noise in the corrected data. The NNBR and PLD methods consistently minimize both white and red noise levels and should be considered reliable and consistent. The planets in this study span equilibrium temperatures from 1100 to 2000 K and have brightness temperatures that require either high albedo or efficient recirculation. However, it is possible that other processes such as clouds or disequilibrium chemistry may also be responsible for producing these brightness temperatures.« less

Spitzer Secondary Eclipse Depths with Multiple Intrapixel Sensitivity Correction Methods Observations of WASP-13b, WASP-15b, WASP-16b, WASP-62b, and HAT-P-22b

NASA Astrophysics Data System (ADS)

Kilpatrick, Brian M.; Lewis, Nikole K.; Kataria, Tiffany; Deming, Drake; Ingalls, James G.; Krick, Jessica E.; Tucker, Gregory S.

2017-01-01

We measure the 4.5 μm thermal emission of five transiting hot Jupiters, WASP-13b, WASP-15b, WASP-16b, WASP-62b, and HAT-P-22b using channel 2 of the Infrared Array Camera (IRAC) on the Spitzer Space Telescope. Significant intrapixel sensitivity variations in Spitzer IRAC data require careful correction in order to achieve precision on the order of several hundred parts per million (ppm) for the measurement of exoplanet secondary eclipses. We determine eclipse depths by first correcting the raw data using three independent data reduction methods. The Pixel Gain Map (PMAP), Nearest Neighbors (NNBR), and Pixel Level Decorrelation (PLD) each correct for the intrapixel sensitivity effect in Spitzer photometric time-series observations. The results from each methodology are compared against each other to establish if they reach a statistically equivalent result in every case and to evaluate their ability to minimize uncertainty in the measurement. We find that all three methods produce reliable results. For every planet examined here NNBR and PLD produce results that are in statistical agreement. However, the PMAP method appears to produce results in slight disagreement in cases where the stellar centroid is not kept consistently on the most well characterized area of the detector. We evaluate the ability of each method to reduce the scatter in the residuals as well as in the correlated noise in the corrected data. The NNBR and PLD methods consistently minimize both white and red noise levels and should be considered reliable and consistent. The planets in this study span equilibrium temperatures from 1100 to 2000 K and have brightness temperatures that require either high albedo or efficient recirculation. However, it is possible that other processes such as clouds or disequilibrium chemistry may also be responsible for producing these brightness temperatures.

The Chemistry of Extragalactic Carbon Stars

NASA Technical Reports Server (NTRS)

Woods, Paul; Walsh, C.; Cordiner, M. A.; Kemper, F.

2013-01-01

Prompted by the ongoing interest in Spitzer Infrared Spectrometer spectra of carbon stars in the Large Magellanic Cloud, we have investigated the circumstellar chemistry of carbon stars in low-metallicity environments. Consistent with observations, our models show that acetylene is particularly abundant in the inner regions of low metallicity carbon-rich asymptotic giant branch stars - more abundant than carbon monoxide. As a consequence, larger hydrocarbons have higher abundances at the metallicities of the Magellanic Clouds than in stars with solar metallicity. We also find that the oxygen and nitrogen chemistry is suppressed at lower metallicity, as expected. Finally, we calculate molecular line emission from carbon stars in the Large and Small Magellanic Cloud and find that several molecules should be readily detectable with the Atacama Large Millimeter Array at Full Science operations.

Evidence for Pulsation-Driven Mass Loss from δ Cephei

NASA Astrophysics Data System (ADS)

Marengo, M.; Evans, N. R.; Matthews, L. D.; Bono, G.; Barmby, P.; Welch, D. L.; Romaniello, M.; Su, K. Y. L.; Fazio, G. G.; Huelsman, D.

We found the first direct evidence that the Cepheid class namesake, δ Cephei, is currently losing mass. These observations are based on data obtained with the Spitzer Space Telescope in the infrared, and with the Very Large Array in the radio. We found that δ Cephei is associated with a vast circumstellar structure, reminiscent of a bow shock. This structure is created as the wind from the star interacts with the local interstellar medium. We measure an outflow velocity of ≈ 35. 5 km s- 1 and a mass loss rate of ≈ 10- 7-10- 6 M ⊙ year- 1. The very low dust content of the outflow suggests that the wind is possibly pulsation-driven, rather than dust-driven as common for other classes of evolved stars.

GeV-gamma-ray emission regions

NASA Image and Video Library

2017-12-08

NASA's Fermi Closes on Source of Cosmic Rays New images from NASA's Fermi Gamma-ray Space Telescope show where supernova remnants emit radiation a billion times more energetic than visible light. The images bring astronomers a step closer to understanding the source of some of the universe's most energetic particles -- cosmic rays. Fermi mapped GeV-gamma-ray emission regions (magenta) in the W44 supernova remnant. The features clearly align with filaments detectable in other wavelengths. This composite merges X-rays (blue) from the Germany-led ROSAT mission, infrared (red) from NASA's Spitzer Space Telescope, and radio (orange) from the Very Large Array near Socorro, N.M. Credit: NASA/DOE/Fermi LAT Collaboration, ROSAT, JPL-Caltech, and NRAO/AUI For more information: www.nasa.gov/mission_pages/GLAST/news/cosmic-rays-source....

A warm Spitzer survey of the LSST/DES 'Deep drilling' fields

NASA Astrophysics Data System (ADS)

Lacy, Mark; Farrah, Duncan; Brandt, Niel; Sako, Masao; Richards, Gordon; Norris, Ray; Ridgway, Susan; Afonso, Jose; Brunner, Robert; Clements, Dave; Cooray, Asantha; Covone, Giovanni; D'Andrea, Chris; Dickinson, Mark; Ferguson, Harry; Frieman, Joshua; Gupta, Ravi; Hatziminaoglou, Evanthia; Jarvis, Matt; Kimball, Amy; Lubin, Lori; Mao, Minnie; Marchetti, Lucia; Mauduit, Jean-Christophe; Mei, Simona; Newman, Jeffrey; Nichol, Robert; Oliver, Seb; Perez-Fournon, Ismael; Pierre, Marguerite; Rottgering, Huub; Seymour, Nick; Smail, Ian; Surace, Jason; Thorman, Paul; Vaccari, Mattia; Verma, Aprajita; Wilson, Gillian; Wood-Vasey, Michael; Cane, Rachel; Wechsler, Risa; Martini, Paul; Evrard, August; McMahon, Richard; Borne, Kirk; Capozzi, Diego; Huang, Jiashang; Lagos, Claudia; Lidman, Chris; Maraston, Claudia; Pforr, Janine; Sajina, Anna; Somerville, Rachel; Strauss, Michael; Jones, Kristen; Barkhouse, Wayne; Cooper, Michael; Ballantyne, David; Jagannathan, Preshanth; Murphy, Eric; Pradoni, Isabella; Suntzeff, Nicholas; Covarrubias, Ricardo; Spitler, Lee

2014-12-01

We propose a warm Spitzer survey to microJy depth of the four predefined Deep Drilling Fields (DDFs) for the Large Synoptic Survey Telescope (LSST) (three of which are also deep drilling fields for the Dark Energy Survey (DES)). Imaging these fields with warm Spitzer is a key component of the overall success of these projects, that address the 'Physics of the Universe' theme of the Astro2010 decadal survey. With deep, accurate, near-infrared photometry from Spitzer in the DDFs, we will generate photometric redshift distributions to apply to the surveys as a whole. The DDFs are also the areas where the supernova searches of DES and LSST are concentrated, and deep Spitzer data is essential to obtain photometric redshifts, stellar masses and constraints on ages and metallicities for the >10000 supernova host galaxies these surveys will find. This 'DEEPDRILL' survey will also address the 'Cosmic Dawn' goal of Astro2010 through being deep enough to find all the >10^11 solar mass galaxies within the survey area out to z~6. DEEPDRILL will complete the final 24.4 square degrees of imaging in the DDFs, which, when added to the 14 square degrees already imaged to this depth, will map a volume of 1-Gpc^3 at z>2. It will find ~100 > 10^11 solar mass galaxies at z~5 and ~40 protoclusters at z>2, providing targets for JWST that can be found in no other way. The Spitzer data, in conjunction with the multiwavelength surveys in these fields, ranging from X-ray through far-infrared and cm-radio, will comprise a unique legacy dataset for studies of galaxy evolution.

Seeing Beyond the Monkey Head

NASA Image and Video Library

2015-08-20

Scores of baby stars shrouded by dust are revealed in this infrared image of the star-forming region NGC 2174, as seen by NASA Spitzer Space Telescope. Found in the constellation Orion, NGC 2174 is located around 6,400 light-years away. Some of the clouds in the region resemble the face of a monkey in visible-light images, hence the nebula's nickname: the "Monkey Head." However, in infrared images such as this, the monkey disappears. That's because different clouds are highlighted in infrared and visible-light images. Found in the northern reaches of the constellation Orion, NGC 2174 is located around 6,400 light-years away. Columns of dust, slightly to the right of center in the image, are being carved out of the dust by radiation and stellar winds from the hottest young stars recently born in the area. Spitzer's infrared view provides us with a preview of the next clusters of stars that will be born in the coming millennia. The reddish spots of light scattered through the darker filaments are infant stars swaddled by blankets of warm dust. The warm dust glows brightly at infrared wavelengths. Eventually, these stars will pop out of their dusty envelopes and their light will carve away at the dust clouds surrounding them. In this image, infrared wavelengths have been assigned visible colors we see with our eyes. Light with a wavelength of 3.5 microns is shown in blue, 8.0 microns is green, and 24 microns in red. The greens show the organic molecules in the dust clouds, illuminated by starlight. Reds are caused by the thermal radiation emitted from the very hottest areas of dust. Areas around the edges that were not observed by Spitzer have been filled in using infrared observations from NASA's Wide Field Infrared Survey Explorer, or WISE. http://photojournal.jpl.nasa.gov/catalog/PIA19836

CONTINUOUS MID-INFRARED STAR FORMATION RATE INDICATORS: DIAGNOSTICS FOR 0 < z < 3 STAR-FORMING GALAXIES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Battisti, A. J.; Calzetti, D.; Johnson, B. D.

2015-02-20

We present continuous, monochromatic star formation rate (SFR) indicators over the mid-infrared wavelength range of 6–70 μm. We use a sample of 58 star-forming galaxies (SFGs) in the Spitzer–SDSS–GALEX Spectroscopic Survey at z < 0.2, for which there is a rich suite of multi-wavelength photometry and spectroscopy from the ultraviolet through to the infrared. The data from the Spitzer Infrared Spectrograph (IRS) of these galaxies, which spans 5–40 μm, is anchored to their photometric counterparts. The spectral region between 40–70 μm is interpolated using dust model fits to the IRS spectrum and Spitzer 70 and 160 μm photometry. Since theremore » are no sharp spectral features in this region, we expect these interpolations to be robust. This spectral range is calibrated as a SFR diagnostic using several reference SFR indicators to mitigate potential bias. Our band-specific continuous SFR indicators are found to be consistent with monochromatic calibrations in the local universe, as derived from Spitzer, WISE, and Herschel photometry. Our local composite template and continuous SFR diagnostics are made available for public use through the NASA/IPAC Infrared Science Archive (IRSA) and have typical dispersions of 30% or less. We discuss the validity and range of applicability for our SFR indicators in the context of unveiling the formation and evolution of galaxies. Additionally, in the era of the James Webb Space Telescope this will become a flexible tool, applicable to any SFG up to z ∼ 3.« less

Infrared Spectroscopy of Star Formation in Galactic and Extragalactic Regions

NASA Technical Reports Server (NTRS)

Smith, Howard A.; Hasan, Hashima (Technical Monitor)

2004-01-01

Last year we submitted and had accepted a paper entitled "The Far-Infrared Emission Line and Continuum Spectrum of the Seyfert Galaxy NGC 1068," by Spinoglio, L., Malkan, M., Smith. HA, Gonzalez-Alfonso, E., and Fischer, J. This analysis was based on the SWAS Monte Carlo code modeling of the OH lines in galaxies observed by ISO. Since that meeting last spring considerable effort has been put into improving the Monte Carlo code. A group of European astronomers, including Prof. Eduardo Gonzalez-Alfonso, had been performing Monte Carlo modeling of other molecules seen in ISO galaxies. We used portions of this grant to bring Prof. Gonzalez-Alfonso to Cambridge for an intensive working visit. A second major paper on the ISO IR spectroscopy of galaxies, "The Far Infrared Spectrum of Arp 220," Gonzalez-Alfonso, E., Smith. H., Fischer, J., and Cernicharo, J., is in press. Spitzer science development was the major component of this past year;s research. This program supported the development of five Early Release Objects for Spitzer observations on which Dr. Smith was Principal Investigator or Co-Investigator, and another five proposals for GO time. The early release program is designed to rapidly present to the public and the scientific community some exciting results from Spitzer in the first months of its operation. The Spitzer instrument and science teams submitted proposals for ERO objects, and a competitive selection process narrowed these down to a small group with exciting science and realistic observational parameters. This grant supported Dr. Smith's participation in the ERO process, including developing science goals, identifying key objects for observation, and developing the detailed AOR (observing formulae) to be use by the instruments for mapping, integrating, etc.). During this year Dr. Smith worked on writing up and publishing these early results. The attached bibliography includes six of Dr. Smith's articles. During this past year Dr. Smith also led or helped to develop proposals for ten Spitzer GO Programs, and three others. Appendix B lists the programs involved.

Neon and [CII] 158 μm Emission Line Profiles in Dusty Starbursts and Active Galactic Nuclei

NASA Astrophysics Data System (ADS)

Samsonyan, A.; Weedman, D.; Lebouteiller, V.; Barry, D.; Sargsyan, L.

2017-07-01

Identifying and understanding the initial formation of massive galaxies and quasars in the early universe is a fundamental goal of observational cosmology. A rapidly developing capability for tracing luminosity sources to high redshifts is the observation of the [CII] 158 μm emission line at redshifts z > 4 using ground based submillimeter interferometers, with detections now having been made to z = 7. This has long been known as the strongest far-infrared line in most sources, often carrying about 1% of the total source luminosity, and is thought to be associated with star formation because it should arise within the photodissociation region (PDR) surrounding starbursts. The sample of 382 extragalactic sources has been analysed that have mid-infrared,high resolution spectroscopy with the Spitzer Infrared Spectrograph (IRS) and also spectroscopy of the [CII] 158 μm line with the Herschel Photodetector Array Camera and Spectrometer (PACS). The emission line profiles of [NeII] 12.81μm , [NeIII] 15.55 μm , and [CII] 158 μm are studied, and intrinsic line widths are determined. All line profiles together with overlays comparing positions of PACS and IRS observations are made available in the Cornell Atlas of Spitzer IRS Sources (CASSIS). Sources are classified from AGN to starburst based on equivalent widths of the 6.2 μm polycyclic aromatic hydrocarbon feature. It is found that intrinsic line widths do not change among classification for [CII], with median widths of 207 km s-1 for AGN, 248 km s-1 for composites, and 233 km s-1 for starbursts. The [NeII] line widths also do not change with classification, but [NeIII] lines are progressively broader from starburst to AGN. A small number of objects with unusually broad lines or unusual redshift differences in any feature are identified.

Obituary: James Houck (1940 - 2015)

NASA Astrophysics Data System (ADS)

Weedman, Daniel; Barry, Donald; Soifer, Thomas

James R. Houck, the leading figure in developing infrared spectroscopy for astrophysics, died in Ithaca, NY, on September 18, 2015, at age 74 from complications of Alzheimer's Disease. He was born on October 5, 1940, in Mobile, Alabama, but lived much of his early life in Pittsburgh, Pennsylvania, where he received his undergraduate degree from Carnegie Institute of Technology. Jim spent his scientific career at Cornell University. He came to Cornell as a physics graduate student in 1962 and remained until his retirement as the Kenneth A. Wallace Professor of Astronomy in 2012. His only year away from Ithaca was as a Guggenheim Fellow at Caltech, and he declined job offers from other universities because of his opinion that Ithaca provided the best environment for raising his family. His passion for learning, doing, and teaching science by building instruments and understanding physics led to great benefits for his students and astronomy colleagues. After receiving his PhD in condensed matter physics, he changed fields to work in astronomy at Cornell. He first collaborated with colleague Martin Harwit to develop a rocket program at Cornell for infrared observations and made numerous treks to the White Sands Missile Range flying payloads on Aerobee sounding rockets. Jim emphasized building spectrographs and making pioneering observations with ground based, airborne, and rocket-borne infrared instrumentation. Jim flew on every airplane NASA provided for astronomy. Those were pioneering times. One of his survival stories was of the Learjet in which both engines flamed out over the Pacific when the pilot did a celebratory barrel role after successful completion of their observations. His observations with rockets and airplanes were primarily of a variety of Galactic objects, including planetary nebulae, HII regions, and stars. But the most notable was an observation on the Convair 990 that produced a prescient discovery paper in 1973 led by Jim which discovered bound water on Mars from infrared absorption at 2.85 microns. The analysis that "this bound water comprises about one percent by weight of the surface material" was confirmed forty years later when the Mars Rover Curiosity determined water content by vaporizing Martian soil. Jim was a crucial participant in NASA's first major infrared space mission, the Infrared Astronomical Satellite (IRAS), especially because of his detector expertise which solved a major focal plane problem for the mission. His archive contains a napkin from a British pub on which he sketched a wiring diagram to show his colleagues how to save the 25 micron detector array. Once the results began from IRAS, Jim's scientific interests moved to extragalactic astronomy. He was a major participant in two of the most significant discoveries from IRAS, announced in 1984: an extended population of optically faint, infrared bright galaxies, and the presence of galaxies with exceptional infrared luminosities (now known as the Ultraluminous Infrared Galaxies, ULIRGs). After the great success of IRAS, NASA begin planning a major infrared mission, first labeled "Shuttle Infrared Telescope Facility" but soon becoming the Space Infrared Telescope Facility (SIRTF), and now operating as the Spitzer Space Telescope. Although hundreds contributed, Jim was among the few individuals who contributed most to the success of Spitzer. His colleagues acknowledged this by awarding him both the NASA Exceptional Scientific Achievement Medal in 2005 and the American Astronomical Society's 2008 Joseph Weber Award for Astronomical Instrumentation, with the citation stating, "It is no exaggeration to say that without Dr. Houck's contributions, modern IR astronomy would never have reached its current level of maturity." Jim was the Principal Investigator for the infrared spectrograph on Spitzer (IRS), initially chosen for the original SIRTF mission. Jim became the vital infrared representative on the review panel setting astronomy's priorities for the 1990s (the "Bahcall Report"), and his persuasive advocacy convinced the panel that SIRTF should be the decade's highest priority. Subsequently, Jim chaired the NASA HQ Astrophysics Advisory Committee and played a crucial role in organizing and participating in legislative advocacy for the SIRTF "new start" that was needed. Jim's extraordinary technical expertise was vital to the essential redesign of SIRTF required to meet NASA targets for the mission cost. Following the success of IRAS, SIRTF was intended primarily as a photometric mission. Jim was the advocate for spectroscopy which subsequently turned out to be the instrument in greatest demand for the cryogenic Spitzer mission. Jim's first scientific paper with the IRS in 2005 announced the presence of a large population of quasars in the early universe so heavily obscured by dust that they had been invisible to optical telescopes. The legacy of the Spitzer IRS is now permanently in place as the "Cornell Atlas of Spitzer IRS Sources" (CASSIS at cassis.sirtf.com), providing an easily accessible archive of mid-infrared spectra (5-37 micron) for everything from outer planet satellites to quasars at the edge of the observable universe. CASSIS will be the fundamental reference archive of mid-infrared spectra for the upcoming James Webb Space Telescope. During all these years of major research projects, Jim maintained a consistent dedication to high quality undergraduate teaching, simultaneously with advising numerous PhD students. His most notable legacy for undergraduates at Cornell was his development by 1974 of a research quality telescope close to campus to teach instrumentation and observational techniques. The 25 inch telescope of the Hartung-Boothroyd Observatory not only trained Cornell students for decades, but was also a testbed for spectrographs. What students felt about Jim was summarized by a former undergraduate who told us, "It is no stretch whatsoever to say that I would not be anything close to what I am today had I not run into Jim in my first Cornell Astro course." To improve Cornell's access to ground based observing, Jim also initiated a partnership with Caltech in the Hale 5 m telescope and led development of Cornell instruments for that facility. The sad aspect of Jim's accomplishments was the distraction from his celebration of the IRS success by the long term care he gave to his beloved wife Elaine. They married in 1965, and Elaine became partially disabled a few years before the Spitzer launch. Jim assembled an extraordinary team to assure the success of the IRS, frequently making grueling trips from Ithaca to Pasadena and hurrying home to care for Elaine, who died in 2011. This combination of dedicated personal affection and incredible talent as an astrophysicist summarizes the uniqueness of James R. Houck. He is survived by his sons, Chris and Robert, and by four grandchildren.

Hunting Elusive SPRITEs with Spitzer

NASA Astrophysics Data System (ADS)

Kohler, Susanna

2017-05-01

In recent years, astronomers have developed many wide-field imaging surveys in which the same targets are observed again and again. This new form of observing has allowed us to discover optical and radio transients explosive or irregular events with durations ranging from seconds to years. The dynamic infrared sky, however, has remained largely unexplored until now.Infrared ExplorationExample of a transient: SPIRITS 14ajc was visible when imaged by SPIRITS in 2014 (left) but it wasnt there during previous imaging between 2004 and 2008 (right). The bottom frame shows the difference between the two images. [Adapted from Kasliwal et al. 2017]Why hunt for infrared transients? Optical wavelengths dont allow us to observe events that are obscured, such that their own structure or their surroundings hide them from our view. Both supernovae and luminous red novae (associated with stellar mergers) are discoverable as infrared transients, and there may well be new types of transients in infrared that we havent seen before!To explore this uncharted territory, a team of scientists developed SPIRITS, the Spitzer Infrared Intensive Transients Survey. Begun in 2014, SPIRITS is a five-year long survey that uses the Spitzer Space Telescope to conduct a systematic search for mid-infrared transients in nearby galaxies.In a recent publication led by Mansi Kasliwal (Caltech and the Carnegie Institution for Science), the SPIRITS team has now detailed how their survey works and what theyve discovered in its first year.The light curves of SPRITEs (red stars) lie in the mid-infared luminosity gap between novae (orange) and supernovae (blue). [Kasliwal et al. 2017]Mystery TransientsKasliwal and collaborators used Spitzer to monitor 190 nearby galaxies. In SPIRITS first year, they found over 1958 variable stars and 43 infrared transient sources. Of these 43 transients, 21 were known supernovae, 4 were in the luminosity range of novae, and 4 had optical counterparts. The remaining 14 events were designated eSPecially Red Intermediate-luminosity Transient Events, or SPRITEs.SPRITEs are unusual infrared transients that lie in the luminosity gap between novae and supernovae, and they have no optical counterparts. They all occur in star-forming galaxies.Search for the CauseWhats the physical origin of these phenomena? The authors explore a number of possible sources, including obscured supernovae, stellar mergers with dusty winds, collapse of extreme stars, or even weak shocks in failed supernovae.Spitzer image of M83, one of the closest barred spiral galaxies in the sky. SPIRITS 14ajc was discovered in one of M83s spiral arms. [NASA/JPL-Caltech]In one case, SPIRITS 14ajc, the SPRITEs spectrum shows signs of excited molecular hydrogen lines, which are indicative of a shock. Based on the data, Kasliwal and collaborators propose that the shock might have been driven into a molecular cloud after it was triggered by the decay of a system of massive stars that either passed closely or collided and merged.The other SPRITEs may all have different origins, however, and in general the infrared photometric data isnt sufficient to identify which model fits each transient. Future technology, like spectroscopy with the James Webb Space Telescope, may help us to better understand the origins of these elusive transients, though. And future surveying with projects like SPIRITS will help us to discover more SPRITE-like events, expanding our understanding of the dynamic infrared sky.CitationMansi M. Kasliwal et al 2017 ApJ 839 88. doi:10.3847/1538-4357/aa6978

EXTRASOLAR STORMS: PRESSURE-DEPENDENT CHANGES IN LIGHT-CURVE PHASE IN BROWN DWARFS FROM SIMULTANEOUS HST AND SPITZER OBSERVATIONS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Hao; Apai, Dániel; Karalidi, Theodora

We present Spitzer /Infrared Array Camera Ch1 and Ch2 monitoring of six brown dwarfs during eight different epochs over the course of 20 months. For four brown dwarfs, we also obtained simulataneous Hubble Space Telescope ( HST )/WFC3 G141 grism spectra during two epochs and derived light curves in five narrowband filters. Probing different pressure levels in the atmospheres, the multiwavelength light curves of our six targets all exhibit variations, and the shape of the light curves evolves over the timescale of a rotation period, ranging from 1.4 to 13 hr. We compare the shapes of the light curves andmore » estimate the phase shifts between the light curves observed at different wavelengths by comparing the phase of the primary Fourier components. We use state-of-the-art atmosphere models to determine the flux contribution of different pressure layers to the observed flux in each filter. We find that the light curves that probe higher pressures are similar and in phase, but are offset and often different from the light curves that probe lower pressures. The phase differences between the two groups of light curves suggest that the modulations seen at lower and higher pressures may be introduced by different cloud layers.« less

Dusty Disks, Diffuse Clouds, and Dim Suns: Galactic Science with the Infrared Spectrograph on the Spitzer Space Telescope

NASA Technical Reports Server (NTRS)

Roellig, T. L.; Watson, D. M.; Uchida, K. I.; Forrest, W. J.; VanCleve, J. E.; Herter, T. L.; Sloan, G. C.; Furlan, E.; Wilson, J. C.; Bernard-Salas, J.

2004-01-01

The Infrared Spectrograph (IRS) on the Spitzer Space Telescope has now been in routine science operations since Dec. 14,2003. The IRS Science Team has used a portion of their guaranteed time to pursue three major science themes in galactic astronomy: the evolution of protostellar disks and debris disks; the composition and evolution of diffuse matter and clouds in the interstellar medium; and the composition and structure of brown dwarfs and low-mass main-sequence stars. We report here on the results from the first five months of IRS observations in these programs. Full IRS Spectra have already been obtained for large samples of YSO/protoplanetary disks in the Taurus and TW Hya associations, and or debris disks around main-sequence stars, in which many aspects of the evolution of planetary systems can be addressed for the first time. As anticipated, the mid-infrared IRS observations of brown dwarfs have yielded important new information about their atmospheres, including the identification of NH3 and measurements of new methane features. This work is based on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under NASA contract 1407. Support for this work was provided by NASA's Office of Space Science.

Dusty Disks, Diffuse Clouds, and Dim Suns - Galactic Science with the Infrared Spectrograph on the Spitzer Space Telescope

NASA Astrophysics Data System (ADS)

Roellig, T. L.; Watson, D. M.; Uchida, K. I.; Forrest, W. J.; Van Cleve, J. E.; Herter, T. L.; Sloan, G. C.; Furlan, E.; Wilson, J. C.; Bernard-Salas, J.; Saumon, D.; Leggett, S.; Chen, C.; Kemper, F.; Hartmann, L.; Marley, M.; Cushing, M.; Mainzer, A. K.; Kirkpatrick, D.; Jura, M.; Houck, J. R.

2004-05-01

The Infrared Spectrograph (IRS) on the Spitzer Space Telescope has now been in routine science operations since Dec. 14, 2003. The IRS Science Team has used a portion of their guaranteed time to pursue three major science themes in galactic astronomy: the evolution of protostellar disks and debris disks; the composition and evolution of diffuse matter and clouds in the interstellar medium; and the composition and structure of brown dwarfs and low-mass main-sequence stars. We report here on the results from the first five months of IRS observations in these programs. Full IRS Spectra have already been obtained for large samples of YSO/protoplanetary disks in the Taurus and TW Hya associations, and of debris disks around main-sequence stars, in which many aspects of the evolution of planetary systems can be addressed for the first time. As anticipated, the mid-infrared IRS observations of brown dwarfs have yielded important new information about their atmospheres, including the identification of NH3 and measurements of new methane features. This work is based on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under NASA contract 1407. Support for this work was provided by NASA's Office of Space Science.

Mid-ir Properties Of Seyferts: Spitzer/irs Spectroscopy Of The Iras 12µM Seyfert Sample

NASA Astrophysics Data System (ADS)

Wu, Yanling; Charmandaris, V.; Huang, J.

2009-05-01

The study of Seyfert galaxies is of particular interest as they trace the build up of SMBH at the centers of galaxies and they are responsible for the most of the cosmic X-ray background at redshift z 0.8. Given the high obscuration of their nuclei by dust extinction, a large fraction of their emitted radiation is absorbed and reemitted in the infrared. It has been recently demonstrated that mid-infrared spectroscopy, in particular with ISO and Spitzer, is a powerful tool to probe the physics of the radiation field of deeply enshrouded galactic nuclei. Here we present our analysis on the properties of Seyfert galaxies based mostly on our uniformly extracted low-resolution Spitzer/IRS 5.5-35micron spectra for 103 Seyfert galaxies, nearly 90% of the local 12 µm IRAS Seyfert sample. We find that we are able to disentangle the AGN/starburst contribution of the mid-IR emission, and estimate the circumnuclear star formation rate using typical mid-IR tracers. We also find that the mid-IR properties of Type 1 and Type 2 Seyferts are indistinguishable at a given luminosiry range, placing constrains both on the infrared optical depth to their nuclei galaxies as well as to the applicability of the unified AGN model.

Epsilon Aurigae's dark side: A thermal phase curve investigation of the near-eclipse phases

NASA Astrophysics Data System (ADS)

Pearson, Richard L.; Stencel, Robert E.; Howell, Steve B.; Hoard, D. W.; Kim, Daryl L.; Russell, Ray W.; Sitko, Michael L.

2017-06-01

The epsilon Aurigae disk-eclipsing binary system moves through a primary eclipse that lasts just over two years and occurs every 27.1-years. It comprises of a warm F0Ia-star (around 7750 K) and an opaque, circumstellar disk hiding an internal B-star (with a temperature greater than 15,000 K). We present new infrared observations from Spitzer's Infrared Array Camera (IRAC, at 3.6 and 4.5 microns) and The Aerospace Corporation’s Broadband Array Spectrograph System (BASS, a 116-element prism system spectrograph spanning 3 - 14 microns) in order to extract the thermal signature of the disk. Previous findings indicate a variable temperature of the disk, depending on its location within the system’s orbit: a 550 +\\- 50 K temperature was identified during eclipse phases, while a 1150 +\\- 50 K temperature was found near secondary—or anti-eclipse—phases by Hoard et al. (2010) and Hoard et al. (2012). We use the latest observations in combination with previously published IRAC and BASS data to compile a more complete thermal phase curve (TPC) of the disk across nearly one-third of the system’s orbit. The TPC indicates heating and cooling effects of the disk, pointing to specific ranges of material properties and disk structure. The observations, process, results, and implications will be presented.

Spitzer Characterization of Transients from the Palomar Transient Factory

NASA Astrophysics Data System (ADS)

Kasliwal, Mansi; Ofek, Eran; Corsi, Alessandra; Nugent, Peter; Kulkarni, Shri; Cao, Yi; Helou, George; Gal-Yam, Avishay; Arcavi, Iair; Ben-Ami, Sagi

2012-12-01

We propose to continue Spitzer/IRAC follow-up of optical transients discovered by the Palomar Transient Factory. Our goals are: (i) probe the mass loss history and characterize the circumstellar environment of supernovae. (ii) construct a late-time bolometric light curve; the mid-infrared observations complement our ground-based optical and near-infrared data and (iii) understand the physical origin of new classes of transients (specifically, intermediate luminosity red transients) where the mystery is literally enshrouded in dust. We select extremely nearby supernovae, both thermonuclear and core-collapse, where the thermal echo is easily detectable in the mid-infrared. We also select peculiar supernovae that show tell-tale signs of circumstellar interaction. We also select rare and red gap transients in the local universe for IRAC follow-up. Additionally, we request low-impact target of opportunity observations for new discoveries in 2013. Our total request is 24 hrs.

Spitzer Characterization of Transients from the Palomar Transient Factory

NASA Astrophysics Data System (ADS)

Kasliwal, Mansi; Goobar, Ariel; Johansson, Joel; Cenko, Brad; Ofek, Eran; Nugent, Peter; Kulkarni, Shri; Cao, Yi; Helou, George; Gal-Yam, Avishay; Arcavi, Iair; Ben-Ami, Sagi

2013-10-01

We propose to continue Spitzer/IRAC follow-up of optical transients discovered by the Palomar Transient Factory. Our goals are: (i) probe the mass loss history and characterize the circumstellar environment of supernovae. (ii) construct a late-time bolometric light curve; the mid-infrared observations complement our ground-based optical and near-infrared data and (iii) understand the physical origin of new classes of transients (specifically, intermediate luminosity red transients) where the mystery is literally enshrouded in dust. We select extremely nearby supernovae, both thermonuclear and core-collapse, where the thermal echo is easily detectable in the mid-infrared. We also select peculiar supernovae that show tell-tale signs of circumstellar interaction. We also select rare and red gap transients in the local universe. Additionally, we request low-impact target of opportunity observations for new discoveries in 2014. Our total request is 17 hrs.

The Great Observatories Origins Deep Survey Spitzer Legacy Science Program

NASA Astrophysics Data System (ADS)

Dickinson, M.; GOODS Team

2005-12-01

The Great Observatories Origins Deep Survey (GOODS) is a multiwavelength anthology of deep field programs using NASA's Great Observatories and the most powerful ground-based facilities to create a public data resource for studying the formation and evolution of galaxies and active galactic nuclei (AGN) throughout cosmic history. GOODS incorporates a Spitzer Legacy Program, which has obtained the deepest observations with that telescope at 3.6 to 24 microns. The Spitzer/IRAC data detect the rest-frame near-infrared light from galaxies out to z ˜ 6, providing valuable information on their stellar populations and masses. The MIPS 24μ m data are a sensitive probe of re-emitted energy from dust-obscured star formation and AGN out to z ˜ 3. I will very briefly introduce the survey and summarize science highlights from the Spitzer data.

Pandora Cluster Seen by Spitzer

NASA Image and Video Library

2016-09-28

This image of galaxy cluster Abell 2744, also called Pandora's Cluster, was taken by the Spitzer Space Telescope. The gravity of this galaxy cluster is strong enough that it acts as a lens to magnify images of more distant background galaxies. This technique is called gravitational lensing. The fuzzy blobs in this Spitzer image are the massive galaxies at the core of this cluster, but astronomers will be poring over the images in search of the faint streaks of light created where the cluster magnifies a distant background galaxy. The cluster is also being studied by NASA's Hubble Space Telescope and Chandra X-Ray Observatory in a collaboration called the Frontier Fields project. In this image, light from Spitzer's infrared channels is colored blue at 3.6 microns and green at 4.5 microns. http://photojournal.jpl.nasa.gov/catalog/PIA20920

Spitzer Clusters

NASA Astrophysics Data System (ADS)

Krick, Kessica

This proposal is a specific response to the strategic goal of NASA's research program to "discover how the universe works and explore how the universe evolved into its present form." Towards this goal, we propose to mine the Spitzer archive for all observations of galaxy groups and clusters for the purpose of studying galaxy evolution in clusters, contamination rates for Sunyaev Zeldovich cluster surveys, and to provide a database of Spitzer observed clusters to the broader community. Funding from this proposal will go towards two years of support for a Postdoc to do this work. After searching the Spitzer Heritage Archive, we have found 194 unique galaxy groups and clusters that have data from both the Infrared array camera (IRAC; Fazio et al. 2004) at 3.6 - 8 microns and the multiband imaging photometer for Spitzer (MIPS; Rieke et al. 2004) at 24microns. This large sample will add value beyond the individual datasets because it will be a larger sample of IR clusters than ever before and will have sufficient diversity in mass, redshift, and dynamical state to allow us to differentiate amongst the effects of these cluster properties. An infrared sample is important because it is unaffected by dust extinction while at the same time is an excellent measure of both stellar mass (IRAC wavelengths) and star formation rate (MIPS wavelengths). Additionally, IRAC can be used to differentiate star forming galaxies (SFG) from active galactic nuclei (AGN), due to their different spectral shapes in this wavelength regime. Specifically, we intend to identify SFG and AGN in galaxy groups and clusters. Groups and clusters differ from the field because the galaxy densities are higher, there is a large potential well due mainly to the mass of the dark matter, and there is hot X-ray gas (the intracluster medium; ICM). We will examine the impact of these differences in environment on galaxy formation by comparing cluster properties of AGN and SFG to those in the field. Also, we will examine the effect that evolutions of cluster redshift and dynamical state have on SFG and AGN in groups and clusters. In addition to environment, we will study the timescales of chemical enrichment of the ICM, using the SFG and AGN as tracers of processes that can transport metals outside of galaxies. Cosmological parameters can be measured based on observing galaxy clusters as signposts of the growth of structure in the universe. The best way to select a redshift independent sample is to use the SZ effect with mm observations to detect a shift in the cosmic microwave background spectrum as those photons scatter off hot gas in clusters. However, such mm observations are contaminated by the emission of SFG and AGN. We intend to characterize the magnitude of this effect on SZ surveys by understanding the frequency, radial distribution, and redshift distribution of these galaxies in clusters. Lastly, a compiled cluster catalog of all Spitzer observed clusters would be useful to the broader astronomical community. We plan to incorporate ancillary multi-wavelength data, where available, and to both publish our catalog in journals, and work with NED to make the catalog easily accessible in an efficient manner by the community.

TIFR Near Infrared Imaging Camera-II on the 3.6 m Devasthal Optical Telescope

NASA Astrophysics Data System (ADS)

Baug, T.; Ojha, D. K.; Ghosh, S. K.; Sharma, S.; Pandey, A. K.; Kumar, Brijesh; Ghosh, Arpan; Ninan, J. P.; Naik, M. B.; D’Costa, S. L. A.; Poojary, S. S.; Sandimani, P. R.; Shah, H.; Krishna Reddy, B.; Pandey, S. B.; Chand, H.

Tata Institute of Fundamental Research (TIFR) Near Infrared Imaging Camera-II (TIRCAM2) is a closed-cycle Helium cryo-cooled imaging camera equipped with a Raytheon 512×512 pixels InSb Aladdin III Quadrant focal plane array (FPA) having sensitivity to photons in the 1-5μm wavelength band. In this paper, we present the performance of the camera on the newly installed 3.6m Devasthal Optical Telescope (DOT) based on the calibration observations carried out during 2017 May 11-14 and 2017 October 7-31. After the preliminary characterization, the camera has been released to the Indian and Belgian astronomical community for science observations since 2017 May. The camera offers a field-of-view (FoV) of ˜86.5‧‧×86.5‧‧ on the DOT with a pixel scale of 0.169‧‧. The seeing at the telescope site in the near-infrared (NIR) bands is typically sub-arcsecond with the best seeing of ˜0.45‧‧ realized in the NIR K-band on 2017 October 16. The camera is found to be capable of deep observations in the J, H and K bands comparable to other 4m class telescopes available world-wide. Another highlight of this camera is the observational capability for sources up to Wide-field Infrared Survey Explorer (WISE) W1-band (3.4μm) magnitudes of 9.2 in the narrow L-band (nbL; λcen˜ 3.59μm). Hence, the camera could be a good complementary instrument to observe the bright nbL-band sources that are saturated in the Spitzer-Infrared Array Camera (IRAC) ([3.6] ≲ 7.92 mag) and the WISE W1-band ([3.4] ≲ 8.1 mag). Sources with strong polycyclic aromatic hydrocarbon (PAH) emission at 3.3μm are also detected. Details of the observations and estimated parameters are presented in this paper.

The 2-Year Checkup on 10 SNe IIn Discovered by Spitzer to Exhibit Late-Time (is greater than 100 Day) IR Emission

NASA Technical Reports Server (NTRS)

Fox, Ori Dosovitz; Chevalier, R. A.; Skrutskie, A. V.; Filippenko, A. V.; Silverman, J. M.; Ganeshalingam, M.

2012-01-01

Two years ago, a warm Spitzer survey of sixty-eight SNe IIn identified between the years 1998-2008 discovered 10 events with unreported late-time infrared (IR) excesses, in some cases more than 5 years post-explosion. These data nearly double the database of existing mid-IR observations of SNe IIn and offer important clues regarding the SN circumstellar.

Cracking the Code of Faraway Worlds

NASA Technical Reports Server (NTRS)

2007-01-01

This infrared data from NASA's Spitzer Space Telescope - called a spectrum - tells astronomers that a distant gas planet, a so-called 'hot Jupiter' called HD 209458b, might be smothered with high clouds. It is one of the first spectra of an alien world.

A spectrum is created when an instrument called a spectrograph spreads light from an object apart into a rainbow of different wavelengths. Patterns or ripples within the spectrum indicate the presence, or absence, of molecules making up the object.

Astronomers using Spitzer's spectrograph were able to obtain infrared spectra for two so-called 'transiting' hot-Jupiter planets using the 'secondary eclipse' technique. In this method, the spectrograph first collects the combined infrared light from the planet plus its star, then, as the planet is eclipsed by the star, the infrared light of just the star. Subtracting the latter from the former reveals the planet's own rainbow of infrared colors.

When astronomers first saw the infrared spectrum above, they were shocked. It doesn't look anything like what theorists had predicted. Theorists though the spectra for hot, Jupiter-like planets like this one would be filled with the signatures of molecules in the planets' atmospheres. But the spectrum doesn't show any molecules. It is what astronomers call 'flat.' For example, theorists thought there'd be signatures of water in the wavelength ranges of 8 to 9 microns. The fact that water is not seen there might indicate that the water is hidden under a thick blanket of high, dry clouds.

This spectrum was produced by Dr. Mark R. Swain of NASA's Jet Propulsion Laboratory in Pasadena, Calif., using a complex set of mathematical tools. It was derived using two different methods, both of which led to the same result. The data were taken on July 6 and 13, 2005, by Dr. Jeremy Richardson of NASA's Goddard Space Flight Center and his team using Spitzer's infrared spectrograph.

The Carnegie Hubble Program

NASA Technical Reports Server (NTRS)

Freedman, Wendy L.; Madore, Barry F.; Scowcroft, Vicky; Mnso, Andy; Persson, S. E.; Rigby, Jane; Sturch, Laura; Stetson, Peter

2011-01-01

We present an overview of and preliminary results from an ongoing comprehensive program that has a goal of determining the Hubble constant to a systematic accuracy of 2%. As part of this program, we are currently obtaining 3.6 micron data using the Infrared Array Camera (IRAC) on Spitzer, and the program is designed to include JWST in the future. We demonstrate that the mid-infrared period-luminosity relation for Cepheids at 3.6 microns is the most accurate means of measuring Cepheid distances to date. At 3.6 microns, it is possible to minimize the known remaining systematic uncertainties in the Cepheid extragalactic distance scale. We discuss the advantages of 3.6 micron observations in minimizing systematic effects in the Cepheid calibration of the Hubble constant including the absolute zero point, extinction corrections, and the effects of metallicity on the colors and magnitudes of Cepheids. We are undertaking three independent tests of the sensitivity of the mid-IR Cepheid Leavitt Law to metallicity, which when combined will allow a robust constraint on the effect. Finally, we are providing a new mid-IR Tully-Fisher relation for spiral galaxies.

METALLICITY AND AGE OF THE STELLAR STREAM AROUND THE DISK GALAXY NGC 5907

DOE Office of Scientific and Technical Information (OSTI.GOV)

Laine, Seppo; Grillmair, Carl J.; Capak, Peter

2016-09-01

Stellar streams have become central to studies of the interaction histories of nearby galaxies. To characterize the most prominent parts of the stellar stream around the well-known nearby ( d  = 17 Mpc) edge-on disk galaxy NGC 5907, we have obtained and analyzed new, deep gri Subaru/Suprime-Cam and 3.6 μ m Spitzer /Infrared Array Camera observations. Combining the near-infrared 3.6 μ m data with visible-light images allows us to use a long wavelength baseline to estimate the metallicity and age of the stellar population along an ∼60 kpc long segment of the stream. We have fitted the stellar spectral energy distributionmore » with a single-burst stellar population synthesis model and we use it to distinguish between the proposed satellite accretion and minor/major merger formation models of the stellar stream around this galaxy. We conclude that a massive minor merger (stellar mass ratio of at least 1:8) can best account for the metallicity of −0.3 inferred along the brightest parts of the stream.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vican, Laura; Zuckerman, B.; Schneider, Adam

We present results from two Herschel observing programs using the Photodetector Array Camera and Spectrometer. During three separate campaigns, we obtained Herschel data for 24 stars at 70, 100, and 160 μ m. We chose stars that were already known or suspected to have circumstellar dust based on excess infrared (IR) emission previously measured with the InfraRed Astronomical Satellite ( IRAS ) or Spitzer and used Herschel to examine long-wavelength properties of the dust. Fifteen stars were found to be uncontaminated by background sources and possess IR emission most likely due to a circumstellar debris disk. We analyzed the propertiesmore » of these debris disks to better understand the physical mechanisms responsible for dust production and removal. Seven targets were spatially resolved in the Herschel images. Based on fits to their spectral energy distributions, nine disks appear to have two temperature components. Of these nine, in three cases, the warmer dust component is likely the result of a transient process rather than a steady-state collisional cascade. The dust belts at four stars are likely stirred by an unseen planet and merit further investigation.« less

The Mid-Infrared Extinction Law in the Ophiuchus, Perseus, and Serpens Molecular Clouds

NASA Astrophysics Data System (ADS)

Chapman, Nicholas L.; Mundy, Lee G.; Lai, Shih-Ping; Evans, Neal J., II

2009-01-01

We compute the mid-IR extinction law from 3.6 to 24 μm in three molecular clouds—Ophiuchus, Perseus, and Serpens—by combining data from the "Cores to Disks" Spitzer Legacy Science program with deep JHKs imaging. Using a new technique, we are able to calculate the line-of-sight (LOS) extinction law toward each background star in our fields. With these LOS measurements, we create, for the first time, maps of the χ2 deviation of the data from two extinction law models. Because our χ2 maps have the same spatial resolution as our extinction maps, we can directly observe the changing extinction law as a function of the total column density. In the Spitzer Infrared Array Camera (IRAC) bands, 3.6-8 μm, we see evidence for grain growth. Below A_{K_s} = 0.5, our extinction law is well fitted by the Weingartner and Draine RV = 3.1 diffuse interstellar-medium dust model. As the extinction increases, our law gradually flattens, and for A_{K_s} \\ge 1, the data are more consistent with the Weingartner and Draine RV = 5.5 model that uses larger maximum dust grain sizes. At 24 μm, our extinction law is 2-4 times higher than the values predicted by theoretical dust models, but is more consistent with the observational results of Flaherty et al. Finally, from our χ2 maps we identify a region in Perseus where the IRAC extinction law is anomalously high considering its column density. A steeper near-IR extinction law than the one we have assumed may partially explain the IRAC extinction law in this region.

A Cauldron of Stars at the Galaxy's Center

NASA Technical Reports Server (NTRS)

2006-01-01

This dazzling infrared image from NASA's Spitzer Space Telescope shows hundreds of thousands of stars crowded into the swirling core of our spiral Milky Way galaxy. In visible-light pictures, this region cannot be seen at all because dust lying between Earth and the galactic center blocks our view.

In this false-color picture, old and cool stars are blue, while dust features lit up by blazing hot, massive stars are shown in a reddish hue. Both bright and dark filamentary clouds can be seen, many of which harbor stellar nurseries. The plane of the Milky Way's flat disk is apparent as the main, horizontal band of clouds. The brightest white spot in the middle is the very center of the galaxy, which also marks the site of a supermassive black hole.

The region pictured here is immense, with a horizontal span of 890 light-years and a vertical span of 640 light-years. Earth is located 26,000 light-years away, out in one of the Milky Way's spiral arms. Though most of the objects seen in this image are located at the galactic center, the features above and below the galactic plane tend to lie closer to Earth.

Scientists are intrigued by the giant lobes of dust extending away from the plane of the galaxy. They believe the lobes may have been formed by winds from massive stars.

This image is a mosaic of thousands of short exposures taken by Spitzer's infrared array camera, showing emissions from wavelengths of 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange), and 8.0 microns (red). The entire region was imaged in less than 16 hours.

DETECTION OF PLANETARY EMISSION FROM THE EXOPLANET TrES-2 USING SPITZER/IRAC

DOE Office of Scientific and Technical Information (OSTI.GOV)

O'Donovan, Francis T.; Charbonneau, David; Knutson, Heather A.

2010-02-20

We present here the results of our observations of TrES-2 using the Infrared Array Camera on Spitzer. We monitored this transiting system during two secondary eclipses, when the planetary emission is blocked by the star. The resulting decrease in flux is 0.127% +- 0.021%, 0.230% +- 0.024%, 0.199% +- 0.054%, and 0.359% +- 0.060% at 3.6 {mu}m, 4.5 {mu}m, 5.8 {mu}m, and 8.0 {mu}m, respectively. We show that three of these flux contrasts are well fit by a blackbody spectrum with T{sub eff} = 1500 K, as well as by a more detailed model spectrum of a planetary atmosphere. Themore » observed planet-to-star flux ratios in all four IRAC channels can be explained by models with and without a thermal inversion in the atmosphere of TrES-2, although with different atmospheric chemistry. Based on the assumption of thermochemical equilibrium, the chemical composition of the inversion model seems more plausible, making it a more favorable scenario. TrES-2 also falls in the category of highly irradiated planets which have been theoretically predicted to exhibit thermal inversions. However, more observations at infrared and visible wavelengths would be needed to confirm a thermal inversion in this system. Furthermore, we find that the times of the secondary eclipses are consistent with previously published times of transit and the expectation from a circular orbit. This implies that TrES-2 most likely has a circular orbit, and thus does not obtain additional thermal energy from tidal dissipation of a non-zero orbital eccentricity, a proposed explanation for the large radius of this planet.« less

Embedded Star Formation in the Eagle Nebula with Spitzer GLIMPSE

NASA Astrophysics Data System (ADS)

Indebetouw, R.; Robitaille, T. P.; Whitney, B. A.; Churchwell, E.; Babler, B.; Meade, M.; Watson, C.; Wolfire, M.

2007-09-01

We present new Spitzer photometry of the Eagle Nebula (M16, containing the optical cluster NGC 6611) combined with near-infrared photometry from 2MASS. We use dust radiative transfer models, mid-infrared and near-infrared color-color analysis, and mid-infrared spectral indices to analyze point-source spectral energy distributions, select candidate YSOs, and constrain their mass and evolutionary state. Comparison of the different protostellar selection methods shows that mid-infrared methods are consistent, but as has been known for some time, near-infrared-only analysis misses some young objects. We reveal more than 400 protostellar candidates, including one massive YSO that has not been previously highlighted. The YSO distribution supports a picture of distributed low-level star formation, with no strong evidence of triggered star formation in the ``pillars.'' We confirm the youth of NGC 6611 by a large fraction of infrared excess sources and reveal a younger cluster of YSOs in the nearby molecular cloud. Analysis of the YSO clustering properties shows a possible imprint of the molecular cloud's Jeans length. Multiwavelength mid-IR imaging thus allows us to analyze the protostellar population, to measure the dust temperature and column density, and to relate these in a consistent picture of star formation in M16.

The Milky Way Center Aglow with Dust

NASA Technical Reports Server (NTRS)

2006-01-01

[figure removed for brevity, see original site] Milky Way Poster

Our Milky Way is a dusty place. So dusty, in fact, that we cannot see the center of the galaxy in visible light. But when NASA's Spitzer Space Telescope set its infrared eyes on the galactic center, it captured this spectacular view.

Taken with just one of Spitzer's cameras (at a wavelength of 8 microns), the image highlights the region's exceptionally bright and dusty clouds, lit up by young massive stars. Individual stars can also be seen as tiny dots scattered throughout the dust. The top mosaic shows a portion of the galactic center that stretches across a distance of 760 light-years.

Thanks to Spitzer's excellent resolution, the dusty features within the galactic center are seen in unprecedented detail. Four examples are shown in the magnified insets at the bottom. The farthest left box shows a pair of star-forming regions resembling owl-like cosmic eyes. To the left of the 'eyes,' dark lanes of dust can be seen. This object is probably located in a spiral arm between Earth and the galactic center, in contrast to the following examples, which are all located at the galactic center.

The next inset to the right includes the extremely luminous 'Quintuplet' stars, a set of five massive stars believed to have buried themselves in cocoons of dust. Just below and to the right of the Quintuplet is the 'Pistol' nebula, a bubble of ejected material from the central, massive Pistol star. The finger-like pillars to the left are part of a structure known as 'Sickle.' They are similar in size and shape to those in the famous picture of the Eagle Nebula taken by NASA's Hubble Space Telescope. Pillars like these are sculpted out of dense dust clouds by radiation and winds from hot stars. The pillars in the Sickle were likely to have been formed by a cluster of hot stars located to their right but not readily visible here.

The third inset highlights a system of long, stringy structures that are seen for the first time near the base of a region known as the 'Arched Filaments.' These long filaments are about 10 light-years long and less than 1 light-year wide. The bright star-forming regions to the right are some of the brightest in the infrared sky.

The final inset to the right shows the center of our galaxy, which is the brightest spot in the entire mosaic. The brightness is a result of dust being heated up by a compact cluster of hot stars. The bright spot also marks the location of a supermassive black hole, around which a rotating ring of gas and dust known as the circumnuclear disk can be seen.

This image was taken with Spitzer's infrared array camera, using its 8-micron detector. It shows emissions from heated molecules in dust clouds called polycyclic aromatic hydrocarbons.

ON THE ORBIT OF EXOPLANET WASP-12b

DOE Office of Scientific and Technical Information (OSTI.GOV)

Campo, Christopher J.; Harrington, Joseph; Hardy, Ryan A.

We observed two secondary eclipses of the exoplanet WASP-12b using the Infrared Array Camera on the Spitzer Space Telescope. The close proximity of WASP-12b to its G-type star results in extreme tidal forces capable of inducing apsidal precession with a period as short as a few decades. This precession would be measurable if the orbit had a significant eccentricity, leading to an estimate of the tidal Love number and an assessment of the degree of central concentration in the planetary interior. An initial ground-based secondary-eclipse phase reported by Lopez-Morales et al. (0.510 {+-} 0.002) implied eccentricity at the 4.5{sigma} level.more » The spectroscopic orbit of Hebb et al. has eccentricity 0.049 {+-} 0.015, a 3{sigma} result, implying an eclipse phase of 0.509 {+-} 0.007. However, there is a well-documented tendency of spectroscopic data to overestimate small eccentricities. Our eclipse phases are 0.5010 {+-} 0.0006 (3.6 and 5.8 {mu}m) and 0.5006 {+-} 0.0007 (4.5 and 8.0 {mu}m). An unlikely orbital precession scenario invoking an alignment of the orbit during the Spitzer observations could have explained this apparent discrepancy, but the final eclipse phase of Lopez-Morales et al. (0.510 {+-}{sup +0.007}{sub -0.006}) is consistent with a circular orbit at better than 2{sigma}. An orbit fit to all the available transit, eclipse, and radial-velocity data indicates precession at <1{sigma}; a non-precessing solution fits better. We also comment on analysis and reporting for Spitzer exoplanet data in light of recent re-analyses.« less

The Spitzer-IRAC Point-source Catalog of the Vela-D Cloud

NASA Astrophysics Data System (ADS)

Strafella, F.; Elia, D.; Campeggio, L.; Giannini, T.; Lorenzetti, D.; Marengo, M.; Smith, H. A.; Fazio, G.; De Luca, M.; Massi, F.

2010-08-01

This paper presents the observations of Cloud D in the Vela Molecular Ridge, obtained with the Infrared Array Camera (IRAC) camera on board the Spitzer Space Telescope at the wavelengths λ = 3.6, 4.5, 5.8, and 8.0 μm. A photometric catalog of point sources, covering a field of approximately 1.2 deg2, has been extracted and complemented with additional available observational data in the millimeter region. Previous observations of the same region, obtained with the Spitzer MIPS camera in the photometric bands at 24 μm and 70 μm, have also been reconsidered to allow an estimate of the spectral slope of the sources in a wider spectral range. A total of 170,299 point sources, detected at the 5σ sensitivity level in at least one of the IRAC bands, have been reported in the catalog. There were 8796 sources for which good quality photometry was obtained in all four IRAC bands. For this sample, a preliminary characterization of the young stellar population based on the determination of spectral slope is discussed; combining this with diagnostics in the color-magnitude and color-color diagrams, the relative population of young stellar objects (YSOs) in different evolutionary classes has been estimated and a total of 637 candidate YSOs have been selected. The main differences in their relative abundances have been highlighted and a brief account for their spatial distribution is given. The star formation rate has also been estimated and compared with the values derived for other star-forming regions. Finally, an analysis of the spatial distribution of the sources by means of the two-point correlation function shows that the younger population, constituted by the Class I and flat-spectrum sources, is significantly more clustered than the Class II and III sources.

The Light and Dark Sides of a Distant Planet

NASA Technical Reports Server (NTRS)

2006-01-01

[figure removed for brevity, see original site] Poster Version

The top graph consists of infrared data from NASA's Spitzer Space Telescope. It tells astronomers that a distant planet, called Upsilon Andromedae b, always has a giant hot spot on the side that faces the star, while the other side is cold and dark. The artist's concepts above the graph illustrate how the planet might look throughout its orbit if viewed up close with infrared eyes.

Spitzer was able to determine the difference in temperature between the two sides of this planet by measuring the planet's infrared light, or heat, at five points during its 4.6-day-long trip around its star. The temperature rose and fell depending on which face, the sunlit or dark, was pointed toward Spitzer's cameras. Those temperature oscillations are traced by the wavy orange curve. They indicate that Upsilon Andromedae b has an extreme range of temperatures across its surface, about 1,400 degrees Celsius (2,550 degrees Fahrenheit). This means that hot gas moving across the bright side of the planet cools off by the time it reaches the dark side.

The bottom graph and artist's concepts represent what astronomers might have seen if the planet had bands of different temperatures girdling it, like Jupiter. Some astronomers had speculated that 'hot-Jupiter' planets like Upsilon Andromedae b, which circle very closely around their stars, might resemble Jupiter in this way. If Upsilon Andromedae b had been like this, there would have been no difference between the average temperatures of the sunlit and dark sides to detect, and Spitzer's data would have appeared as a flat line.

A Million Comet Pieces

NASA Technical Reports Server (NTRS)

2006-01-01

[figure removed for brevity, see original site] A Million Comet Pieces (poster version)

This infrared image from NASA's Spitzer Space Telescope shows the broken Comet 73P/Schwassman-Wachmann 3 skimming along a trail of debris left during its multiple trips around the sun. The flame-like objects are the comet's fragments and their tails, while the dusty comet trail is the line bridging the fragments.

Comet 73P /Schwassman-Wachmann 3 began to splinter apart in 1995 during one of its voyages around the sweltering sun. Since then, the comet has continued to disintegrate into dozens of fragments, at least 36 of which can be seen here. Astronomers believe the icy comet cracked due the thermal stress from the sun.

The Spitzer image provides the best look yet at the trail of debris left in the comet's wake after its 1995 breakup. The observatory's infrared eyes were able to see the dusty comet bits and pieces, which are warmed by sunlight and glow at infrared wavelengths. This comet debris ranges in size from pebbles to large boulders. When Earth passes near this rocky trail every year, the comet rubble burns up in our atmosphere, lighting up the sky in meteor showers. In 2022, Earth is expected to cross close to the comet's trail, producing a noticeable meteor shower.

Astronomers are studying the Spitzer image for clues to the comet's composition and how it fell apart. Like NASA's Deep Impact experiment, in which a probe smashed into comet Tempel 1, the cracked Comet 73P/Schwassman-Wachmann 3 provides a perfect laboratory for studying the pristine interior of a comet.

This image was taken from May 4 to May 6 by Spitzer's multi-band imaging photometer, using its 24-micron wavelength channel.

Additional Spitzer IRS Spectroscopy of Three Intermediate Polars: The Detection of a Mid-infrared Synchrotron Flare from V1223 Sagittarii

NASA Astrophysics Data System (ADS)

Harrison, Thomas E.; Bornak, Jillian; Rupen, Michael P.; Howell, Steve B.

2010-02-01

We present new Spitzer Infrared Spectrograph (IRS) observations of three intermediate polars: V1223 Sgr, EX Hya, and V603 Aql. We detected a strong, fading flare event from V1223 Sgr. During this event, the flux declined by a factor of 13 in 30 minutes. Given the similarity in the slope of its mid-infrared spectrum during this event to that of AE Aqr, we suggest that this event was caused by transient synchrotron emission. Thus, V1223 Sgr becomes the third cataclysmic variable known to be a synchrotron source. We were unable to confirm the mid-infrared excess noted by Harrison et al. (Paper I) for EX Hya, suggesting that this object is either not a synchrotron source, or is slightly variable. Due to a very high background, V603 Aql was not detected in the long-wavelength regions accessible to the IRS. Given the recent detection of SS Cygni at radio wavelengths during outburst, we extract archival Spitzer IRS spectra for this source obtained during two successive maxima. These spectra do not show a strong excess, but without simultaneous data at shorter wavelengths, it is not possible to determine whether there is any contribution to the mid-infrared fluxes from a synchrotron jet. Includes observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Science and Technology Facilities Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministério da Ciência e Tecnologia (Brazil), and Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina).

Spitzer observations of NGC 2264: the nature of the disk population

NASA Astrophysics Data System (ADS)

Teixeira, P. S.; Lada, C. J.; Marengo, M.; Lada, E. A.

2012-04-01

Aims: NGC 2264 is a young cluster with a rich circumstellar disk population which makes it an ideal target for studying the evolution of stellar clusters. Our goal is to study the star formation history of NGC 2264 and to analyse the primordial disk evolution of its members. Methods: The study presented is based on data obtained with the Infrared Array Camera (IRAC) and the Multiband Imaging Photometer for Spitzer (MIPS) on board the Spitzer Space Telescope, combined with deep near-infrared (NIR) ground-based FLAMINGOS imaging and previously published optical data. Results: We build NIR dust extinction maps of the molecular cloud associated with the cluster, and determine it to have a mass of 2.1 × 103 M⊙ above an AV of 7 mag. Using a differential Ks-band luminosity function (KLF) of the cluster, we estimate the size of the population of NGC 2264, within the area observed by FLAMINGOS, to be 1436 ± 242 members. The star formation efficiency is ≥ ~25%. We identify the disk population and divide it into 3 groups based on their spectral energy distribution slopes from 3.6 μm to 8 μm and on the 24 μm excess emission: (i) optically thick inner disks, (ii) anaemic inner disks, and (iii) disks with inner holes, or transition disks. We analyse the spatial distribution of these sources and find that sources with thick disks segregate into sub-clusterings, whereas sources with anaemic disks do not. Furthermore, sources with anaemic disks are found to be unembedded (i.e., with AV < 3 mag), whereas the clustered sources with thick disks are still embedded within the parental cloud. Conclusions: NGC 2264 has undergone more than one star-forming event, where the anaemic and extincted thick disk population appear to have formed in separate episodes: the sources with anaemic disks are more evolved and have had time to disperse and populate a halo of the cluster. We also find tentative evidence of triggered star-formation in the Fox Fur Nebula. In terms of disk evolution, our findings support the emerging disk evolution paradigm of two distinct evolutionary paths for primordial optically thick disks: a homologous one where the disk emission decreases uniformly at NIR and mid-infrared (MIR) wavelengths, and a radially differential one where the emission from the inner region of the disk decreases more rapidly than from the outer region (forming transition disks).

Cold Probes of the Hot Universe

NASA Technical Reports Server (NTRS)

Kilbourne, Caroline

2017-01-01

In this image, data from NASA's Spitzer, Hubble, and Chandra satellites are combined. Optical light from stars (yellow-greenHubble) shows the disk of an apparently normal galaxy. Another Hubble observation designed to image 10,000 K hydrogen gas (orange) reveals matter blasting out of the galaxy. The Spitzer infrared image (red) shows that cool gas and dust are also being ejected. Chandra's X-ray image (blue) reveals gas that has been heated to millions of degrees by the violent outflow.

Infrared Continuum and Line Evolution of the Equatorial Ring Around SN 1987A

NASA Technical Reports Server (NTRS)

Arendt, Richard G.; Dwek, Eli; Bouchet, Patrice; Danziger, I. John; Frank, Kari A.; Gehrz, Robert D.; Park, Sangwook; Woodward, Charles E.

2017-01-01

Spitzer observations of SN 1987A have now spanned more than a decade. Since day approximately 4000, mid-infrared (mid-IR) emission has been dominated by that from shock-heated dust in the equatorial ring (ER). From 6000 to 8000 days after the explosion, Spitzer observations included broadband photometry at 3.6-24 micrometer, and low and moderate resolution spectroscopy at 5-35 micrometer. Here we present later Spitzer observations, through day 10,377, which include only the broadband measurements at 3.6 and 4.5 micrometer. These data show that the 3.6 and 4.5 micrometer brightness has clearly begun to fade after day approximately 8500, and no longer tracks the X-ray emission as well as it did at earlier epochs. This can be explained by the destruction of the dust in the ER on timescales shorter than the cooling time for the shocked gas. We find that the evolution of the late time IR emission is also similar to the now fading optical emission. We provide the complete record of the IR emission lines, as seen by Spitzer prior to day 8000. The past evolution of the gas as seen by the IR emission lines seems largely consistent with the optical emission, although the IR [Fe(II)]and [Si(II)]lines show different, peculiar velocity structures.

Applications of machine-learning algorithms for infrared colour selection of Galactic Wolf-Rayet stars

NASA Astrophysics Data System (ADS)

Morello, Giuseppe; Morris, P. W.; Van Dyk, S. D.; Marston, A. P.; Mauerhan, J. C.

2018-01-01

We have investigated and applied machine-learning algorithms for infrared colour selection of Galactic Wolf-Rayet (WR) candidates. Objects taken from the Spitzer Galactic Legacy Infrared Midplane Survey Extraordinaire (GLIMPSE) catalogue of the infrared objects in the Galactic plane can be classified into different stellar populations based on the colours inferred from their broad-band photometric magnitudes [J, H and Ks from 2 Micron All Sky Survey (2MASS), and the four Spitzer/IRAC bands]. The algorithms tested in this pilot study are variants of the k-nearest neighbours approach, which is ideal for exploratory studies of classification problems where interrelations between variables and classes are complicated. The aims of this study are (1) to provide an automated tool to select reliable WR candidates and potentially other classes of objects, (2) to measure the efficiency of infrared colour selection at performing these tasks and (3) to lay the groundwork for statistically inferring the total number of WR stars in our Galaxy. We report the performance results obtained over a set of known objects and selected candidates for which we have carried out follow-up spectroscopic observations, and confirm the discovery of four new WR stars.

The Milky Way Project: What are Yellowballs?

NASA Astrophysics Data System (ADS)

Kerton, C. R.; Wolf-Chase, G.; Arvidsson, K.; Lintott, C. J.; Simpson, R. J.

2015-02-01

Yellowballs are a collection of approximately 900 compact, infrared sources identified and named by volunteers participating in the Milky Way Project (MWP), a citizen science project that uses GLIMPSE/MIPSGAL images from Spitzer to explore topics related to Galactic star formation. In this paper, through a combination of catalog cross-matching and infrared color analysis, we show that yellowballs are a mix of compact star-forming regions, including ultra-compact and compact H II regions, as well as analogous regions for less massive B-type stars. The resulting MWP yellowball catalog provides a useful complement to the Red MSX Source survey. It similarly highlights regions of massive star formation, but the selection of objects purely on the basis of their infrared morphology and color in Spitzer images identifies a signature of compact star-forming regions shared across a broad range of luminosities and, by inference, masses. We discuss the origin of their striking mid-infrared appearance and suggest that future studies of the yellowball sample will improve our understanding of how massive and intermediate-mass star-forming regions transition from compact to more extended bubble-like structures.

Updated 34-band Photometry for the SINGS/KINGFISH Samples of Nearby Galaxies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dale, D. A.; Turner, J. A.; Cook, D. O.

2017-03-01

We present an update to the ultraviolet-to-radio database of global broadband photometry for the 79 nearby galaxies that comprise the union of the KINGFISH (Key Insights on Nearby Galaxies: A Far-Infrared Survey with Herschel ) and SINGS ( Spitzer Infrared Nearby Galaxies Survey) samples. The 34-band data set presented here includes contributions from observational work carried out with a variety of facilities including GALEX , SDSS, Pan-STARRS1, NOAO , 2MASS, Wide-Field Infrared Survey Explorer , Spitzer , Herschel , Planck , JCMT , and the VLA. Improvements of note include recalibrations of previously published SINGS BVR {sub C} I {submore » C} and KINGFISH far-infrared/submillimeter photometry. Similar to previous results in the literature, an excess of submillimeter emission above model predictions is seen primarily for low-metallicity dwarf or irregular galaxies. This 33-band photometric data set for the combined KINGFISH+SINGS sample serves as an important multiwavelength reference for the variety of galaxies observed at low redshift. A thorough analysis of the observed spectral energy distributions is carried out in a companion paper.« less

The Optical Green Valley Versus Mid-infrared Canyon in Compact Groups

NASA Technical Reports Server (NTRS)

Walker, Lisa May; Butterfield, Natalie; Johnson, Kelsey; Zucker, Catherine; Gallagher, Sarah; Konstantopoulos, Iraklis; Zabludoff, Ann; Hornschemeier, Ann E.; Tzanavaris, Panayiotis; Charlton, Jane C.

2013-01-01

Compact groups of galaxies provide conditions similar to those experienced by galaxies in the earlier universe. Recent work on compact groups has led to the discovery of a dearth of mid-infrared transition galaxies (MIRTGs) in Infrared Array Camera (3.6-8.0 micrometers) color space as well as at intermediate specific star formation rates. However, we find that in compact groups these MIRTGs have already transitioned to the optical ([g-r]) red sequence. We investigate the optical color-magnitude diagram (CMD) of 99 compact groups containing 348 galaxies and compare the optical CMD with mid-infrared (mid-IR) color space for compact group galaxies. Utilizing redshifts available from Sloan Digital Sky Survey, we identified new galaxy members for four groups. By combining optical and mid-IR data, we obtain information on both the dust and the stellar populations in compact group galaxies. We also compare with more isolated galaxies and galaxies in the Coma Cluster, which reveals that, similar to clusters, compact groups are dominated by optically red galaxies. While we find that compact group transition galaxies lie on the optical red sequence, LVL (Local Volume Legacy) + (plus) SINGS (Spitzer Infrared Nearby Galaxies Survey) mid-IR (infrared) transition galaxies span the range of optical colors. The dearth of mid-IR transition galaxies in compact groups may be due to a lack of moderately star-forming low mass galaxies; the relative lack of these galaxies could be due to their relatively small gravitational potential wells. This makes them more susceptible to this dynamic environment, thus causing them to more easily lose gas or be accreted by larger members.

THE MID-INFRARED EVOLUTION OF THE FU ORIONIS DISK

DOE Office of Scientific and Technical Information (OSTI.GOV)

Green, Joel D.; Jones, Olivia C.; Poteet, Charles A.

2016-11-20

We present new SOFIA-FORCAST observations obtained in 2016 February of the archetypal outbursting low-mass young stellar object FU Orionis, and we compare the continuum, solid-state, and gas properties with mid-infrared data obtained at the same wavelengths in 2004 with Spitzer -IRS. In this study, we conduct the first mid-infrared spectroscopic comparison of an FUor over a long time period. Over a 12-year period, UBVR monitoring indicates that FU Orionis has continued its steady decrease in overall brightness by ∼14%. We find that this decrease in luminosity occurs only at wavelengths ≲20 μ m. In particular, the continuum shortward of the silicate emission complex atmore » 10 μ m exhibits a ∼12% (∼3 σ ) drop in flux density but no apparent change in slope; both the Spitzer and SOFIA spectra are consistent with a 7200 K blackbody. Additionally, the detection of water absorption is consistent with the Spitzer spectrum. The silicate emission feature at 10 μ m continues to be consistent with unprocessed grains, unchanged over 12 years. We conclude that either the accretion rate in FU Orionis has decreased by ∼12–14% over this time baseline or the inner disk has cooled, but the accretion disk remains in a superheated state outside the innermost region.« less

Spectral calibration in the mid-infrared: Challenges and solutions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sloan, G. C.; Herter, T. L.; Houck, J. R.

2015-01-01

We present spectra obtained with the Infrared Spectrograph on the Spitzer Space Telescope of 33 K giants and 20 A dwarfs to assess their suitability as spectrophotometric standard stars. The K giants confirm previous findings that the strength of the SiO absorption band at 8 μm increases for both later optical spectral classes and redder (B–V){sub 0} colors, but with considerable scatter. For K giants, the synthetic spectra underpredict the strengths of the molecular bands from SiO and OH. For these reasons, the assumed true spectra for K giants should be based on the assumption that molecular band strengths inmore » the infrared can be predicted accurately from neither optical spectral class or color nor synthetric spectra. The OH bands in K giants grow stronger with cooler stellar temperatures, and they are stronger than predicted by synthetic spectra. As a group, A dwarfs are better behaved and more predictable than the K giants, but they are more likely to show red excesses from debris disks. No suitable A dwarfs were located in parts of the sky continuously observable from Spitzer, and with previous means of estimating the true spectra of K giants ruled out, it was necessary to use models of A dwarfs to calibrate spectra of K giants from observed spectral ratios of the two groups and then use the calibrated K giants as standards for the full database of infrared spectra from Spitzer. We also describe a lingering artifact that affects the spectra of faint blue sources at 24 μm.« less

A GLIMPSE of Star Formation in the Outer Galaxy

NASA Astrophysics Data System (ADS)

Winston, Elaine; Hora, Joseph L.; Tolls, Volker

2018-01-01

The wealth of infrared data provided by recent infrared missions such as Spitzer, Herschel, and WISE has yet to be fully mined in the study of star formation in the outer galaxy. The nearby galaxy and massive star forming regions towards the galactic center have been extensively studied. However the outer regions of the Milky Way, where the metallicity is intermediate in value between the inner galactic disk and the Magellanic Clouds, has not been systematically studied. We are using Spitzer/IRAC’s GLIMPSE (Galactic Legacy Infrared Mid-plane Survey Extraordinaire) observations of the galactic plane at 3.6, 4.5, 5.8, and 8.0 microns to identify young stellar objects (YSOs) via their disk emission in the mid-infrared. A tiered clustering analysis is then performed: preliminary large scale clustering is identified across the field using a Density-Based Spatial Clustering of Applications with Noise (DBSCAN) technique. Smaller scale sub clustering within these regions is performed using an implementation of the Minimum Spanning Tree (MST) technique. The YSOs are then compared to known objects in the SIMBAD catalogue and their photometry and cluster membership is augmented using available Herschel and WISE photometry. We compare our results to those in the inner galaxy to determine how dynamical processes and environmental factors affect the star formation efficiency. These results will have applications to the study of star formation in other galaxies, where only global properties can be determined. We will present here the results of our initial investigation into star formation in the outer galaxy using the Spitzer/GLIMPSE observations of the SMOG field.

Absolute photometric calibration of IRAC: lessons learned using nine years of flight data

NASA Astrophysics Data System (ADS)

Carey, S.; Ingalls, J.; Hora, J.; Surace, J.; Glaccum, W.; Lowrance, P.; Krick, J.; Cole, D.; Laine, S.; Engelke, C.; Price, S.; Bohlin, R.; Gordon, K.

2012-09-01

Significant improvements in our understanding of various photometric effects have occurred in the more than nine years of flight operations of the Infrared Array Camera aboard the Spitzer Space Telescope. With the accumulation of calibration data, photometric variations that are intrinsic to the instrument can now be mapped with high fidelity. Using all existing data on calibration stars, the array location-dependent photometric correction (the variation of flux with position on the array) and the correction for intra-pixel sensitivity variation (pixel-phase) have been modeled simultaneously. Examination of the warm mission data enabled the characterization of the underlying form of the pixelphase variation in cryogenic data. In addition to the accumulation of calibration data, significant improvements in the calibration of the truth spectra of the calibrators has taken place. Using the work of Engelke et al. (2006), the KIII calibrators have no offset as compared to the AV calibrators, providing a second pillar of the calibration scheme. The current cryogenic calibration is better than 3% in an absolute sense, with most of the uncertainty still in the knowledge of the true flux densities of the primary calibrators. We present the final state of the cryogenic IRAC calibration and a comparison of the IRAC calibration to an independent calibration methodology using the HST primary calibrators.

NEAR-INFRARED THERMAL EMISSION FROM TrES-3b: A Ks-BAND DETECTION AND AN H-BAND UPPER LIMIT ON THE DEPTH OF THE SECONDARY ECLIPSE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Croll, Bryce; Jayawardhana, Ray; Fortney, Jonathan J.

2010-08-01

We present H- and Ks-band photometry bracketing the secondary eclipse of the hot Jupiter TrES-3b using the Wide-field Infrared Camera on the Canada-France-Hawaii Telescope. We detect the secondary eclipse of TrES-3b with a depth of 0.133{sup +0.018}{sub -0.016}% in the Ks band (8{sigma})-a result that is in sharp contrast to the eclipse depth reported by de Mooij and Snellen. We do not detect its thermal emission in the H band, but place a 3{sigma} limit of 0.051% on the depth of the secondary eclipse in this band. A secondary eclipse of this depth in Ks requires very efficient day-to-nightside redistributionmore » of heat and nearly isotropic reradiation, a conclusion that is in agreement with longer wavelength, mid-infrared Spitzer observations. Our 3{sigma} upper limit on the depth of our H-band secondary eclipse also argues for very efficient redistribution of heat and suggests that the atmospheric layer probed by these observations may be well homogenized. However, our H-band upper limit is so constraining that it suggests the possibility of a temperature inversion at depth, or an absorbing molecule, such as methane, that further depresses the emitted flux at this wavelength. The combination of our near-infrared measurements and those obtained with Spitzer suggests that TrES-3b displays a near-isothermal dayside atmospheric temperature structure, whose spectrum is well approximated by a blackbody. We emphasize that our strict H-band limit is in stark disagreement with the best-fit atmospheric model that results from longer wavelength observations only, thus highlighting the importance of near-infrared observations at multiple wavelengths, in addition to those returned by Spitzer in the mid-infrared, to facilitate a comprehensive understanding of the energy budgets of transiting exoplanets.« less

Time Delay in Microlensing Event

NASA Image and Video Library

2015-04-14

This plot shows data obtained from NASA's Spitzer Space Telescope and the Optical Gravitational Lensing Experiment, or OGLE, telescope located in Chile, during a "microlensing" event. Microlensing events occur when one star passes another, and the gravity of the foreground star causes the distant star's light to magnify and brighten. This magnification is evident in the plot, as both Spitzer and OGLE register an increase in the star's brightness. If the foreground star is circled by a planet, the planet's gravity can alter the magnification over a shorter period, seen in the plot in the form of spikes and a dip. The great distance between Spitzer, in space, and OGLE, on the ground, meant that Spitzer saw this particular microlensing event before OGLE. The offset in the timing can be used to measure the distance to the planet. In this case, the planet, called OGLE-2014-BLG-0124L, was found to be 13,000 light-years away, near the center of our Milky Way galaxy. The finding was the result of fortuitous timing because Spitzer's overall program to observe microlensing events was only just starting up in the week before the planet's effects were visible from Spitzer's vantage point. While Spitzer sees infrared light of 3.6 microns in wavelength, OGLE sees visible light of 0.8 microns. http://photojournal.jpl.nasa.gov/catalog/PIA19331

Thermal Emission Spectroscopy (5.2 To 38 Microns) And Analysis Of 10 Near-earth Asteroids

NASA Astrophysics Data System (ADS)

Dave, Riddhi; Emery, J.; Cruikshank, D.; Mueller, M.; Delbo, M.; Trilling, D. E.; Mommert, M.

2010-10-01

Near Earth Asteroids (NEAs- 0.983AU

Spitzer Observations of MF 16 Nebula and the Associated Ultraluminous X-Ray Source

DTIC Science & Technology

2012-06-01

reserved. Printed in the U.S.A. SPITZER OBSERVATIONS OF MF 16 NEBULA AND THE ASSOCIATED ULTRALUMINOUS X-RAY SOURCE C. T. Berghea and R. P. Dudik United...associated nebula MF 16. This ULX has very similar properties to the famous Holmberg II ULX, the first ULX to show a prominent infrared [O iv] emission...the most interesting developments in ULX history is the discovery in recent years of large ionized bubble nebulae around some of the most famous ULXs

Infrared and Radio Observations of a Small Group of Protostellar Objects in the Molecular Core, L1251-C

NASA Astrophysics Data System (ADS)

Kim, Jungha; Lee, Jeong-Eun; Choi, Minho; Bourke, Tyler L.; Evans, Neal J., II; Di Francesco, James; Cieza, Lucas A.; Dunham, Michael M.; Kang, Miju

2015-05-01

We present a multi-wavelength observational study of a low-mass star-forming region, L1251-C, with observational results at wavelengths from the near-infrared to the millimeter. Spitzer Space Telescope observations confirmed that IRAS 22343+7501 is a small group of protostellar objects. The extended emission in the east-west direction with its intensity peak at the center of L1251A has been detected at 350 and 850 μm with the Caltech Submillimeter Observatory and James Clerk Maxwell telescopes, tracing dense envelope material around L1251A. The single-dish data from the Korean VLBI Network and TRAO telescopes show inconsistencies between the intensity peaks of several molecular emission lines and that of the continuum emission, suggesting complex distributions of molecular abundances around L1251A. The Submillimeter Array interferometer data, however, show intensity peaks of CO 2-1 and 13CO 2-1 located at the position of IRS 1, which is both the brightest source in the Infrared Array Camera image and the weakest source in the 1.3 mm dust-continuum map. IRS 1 is the strongest candidate for the driving source of the newly detected compact CO 2-1 outflow. Over the entire region (14‧ × 14‧) of L125l-C, 3 Class I and 16 Class II sources have been detected, including three young stellar objects (YSOs) in L1251A. A comparison between the average projected distance among the 19 YSOs in L1251-C and that among the 3 YSOs in L1251A suggests that L1251-C is an example of low-mass cluster formation where protostellar objects form in a small group.

Cassiopeia A: Death Becomes Her

NASA Technical Reports Server (NTRS)

2005-01-01

This stunning false-color picture shows off the many sides of the supernova remnant Cassiopeia A. It is made up of images taken by three of NASA's Great Observatories, using three different wavebands of light. Infrared data from the Spitzer Space Telescope are colored red; visible data from the Hubble Space Telescope are yellow; and X-ray data from the Chandra X-ray Observatory are green and blue.

Located 10,000 light-years away in the northern constellation Cassiopeia, Cassiopeia A is the remnant of a once massive star that died in a violent supernova explosion 325 years ago. It consists of a dead star, called a neutron star, and a surrounding shell of material that was blasted off as the star died. The neutron star can be seen in the Chandra data as a sharp turquoise dot in the center of the shimmering shell.

Each Great Observatory highlights different characteristics of this celestial orb. While Spitzer reveals warm dust in the outer shell about a few hundred degrees Kelvin (80 degrees Fahrenheit) in temperature, Hubble sees the delicate filamentary structures of hot gases about 10,000 degrees Kelvin (18,000 degrees Fahrenheit). Chandra probes unimaginably hot gases, up to about 10 million degrees Kelvin (18 million degrees Fahrenheit). These extremely hot gases were created when ejected material from Cassiopeia A smashed into surrounding gas and dust. Chandra can also see Cassiopeia A's neutron star (turquoise dot at center of shell).

Blue Chandra data were acquired using broadband X-rays (low to high energies); green Chandra data correspond to intermediate energy X-rays; yellow Hubble data were taken using a 900 nanometer-wavelength filter, and red Spitzer data are from the telescope's 24-micron detector.

The animation begins with the false-color picture of the supernova remnant Cassiopeia A. It then pans out to show a Spitzer view of Cassiopeia A (yellow ball) and surrounding clouds of dust (reddish orange). Here, the animation flips back and forth between two Spitzer images taken one year apart. A blast of light from Cassiopeia A is seen waltzing through the dusty skies. Called an 'infrared echo,' this dance began when the remnant's dead star erupted, or 'turned in its grave,' about 50 years ago.

Infrared echoes are created when a star explodes or erupts, flashing light into surrounding clumps of dust. As the light zips through the dust clumps, it heats them up, causing them to glow successively in infrared, like a chain of Christmas bulbs lighting up one by one. The result is an optical illusion, in which the dust appears to be flying outward at the speed of light. Echoes are distinct from supernova shockwaves, which are made up material that is swept up and hurled outward by exploding stars.

This infrared echo is the largest ever seen, stretching more than 50 light-years away from Cassiopeia A. If viewed from Earth, the entire movie frame would take up the same amount of space as two full moons.

Hints of an older infrared echo from Cassiopeia A's supernova explosion hundreds of years ago can also be seen.

The earlier Spitzer image was taken on November 30, 2003, and the later, on December 2, 2004.

The Contribution of TP-AGB Stars to the Mid-infrared Colors of Nearby Galaxies

NASA Astrophysics Data System (ADS)

Chisari, Nora E.; Kelson, Daniel D.

2012-07-01

We study the mid-infrared color space of 30 galaxies from the Spitzer Infrared Nearby Galaxies Survey (SINGS) survey for which Sloan Digital Sky Survey data are also available. We construct two-color maps for each galaxy and compare them to results obtained from combining Maraston evolutionary synthesis models, galactic thermally pulsating asymptotic giant branch (TP-AGB) colors, and smooth star formation histories. For most of the SINGS sample, the spatially extended mid-IR emission seen by Spitzer in normal galaxies is consistent with our simple model in which circumstellar dust from TP-AGB stars dominates at 8 and 24 μm. There is a handful of exceptions that we identify as galaxies that have high star formation rates presumably with star formation histories that cannot be assumed to be smooth, or anemic galaxies, which were depleted of their H I at some point during their evolution and have very low ongoing star formation rates.

THE CONTRIBUTION OF TP-AGB STARS TO THE MID-INFRARED COLORS OF NEARBY GALAXIES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chisari, Nora E.; Kelson, Daniel D., E-mail: nchisari@astro.princeton.edu

2012-07-10

We study the mid-infrared color space of 30 galaxies from the Spitzer Infrared Nearby Galaxies Survey (SINGS) survey for which Sloan Digital Sky Survey data are also available. We construct two-color maps for each galaxy and compare them to results obtained from combining Maraston evolutionary synthesis models, galactic thermally pulsating asymptotic giant branch (TP-AGB) colors, and smooth star formation histories. For most of the SINGS sample, the spatially extended mid-IR emission seen by Spitzer in normal galaxies is consistent with our simple model in which circumstellar dust from TP-AGB stars dominates at 8 and 24 {mu}m. There is a handfulmore » of exceptions that we identify as galaxies that have high star formation rates presumably with star formation histories that cannot be assumed to be smooth, or anemic galaxies, which were depleted of their H I at some point during their evolution and have very low ongoing star formation rates.« less

Missing GRB host galaxies in deep mid-infrared observations: implications on the use of GRBs as star formation tracers

NASA Astrophysics Data System (ADS)

Le Floc'h, Emeric; Charmandaris, Vassilis; Forrest, Bill; Mirabel, Félix; Armus, Lee; Devost, Daniel

2006-05-01

We report on the first mid-infrared observations of 16 GRB host galaxies performed with the Spitzer Space Telescope, and investigate the presence of evolved stellar populations and dust-enshrouded star-forming activity associated with GRBs. Only a very small fraction of our sample is detected by Spitzer, which is not consistent with recent works suggesting the presence of a GRB host population dominated by massive and strongly-starbursting galaxies (SFR >~ 100Msolaryr-1). Should the GRB hosts be representative of star-forming galaxies at high redshift, models of galaxy evolution indicate that >~ 50% of GRB hosts would be easily detected at the depth of our mid-infrared observations. Unless our sample suffers from a strong observational bias which remains to be understood, we infer in this context that the GRBs identified with the current techniques can not be directly used as unbiased probes of the global and integrated star formation history of the Universe.

Atmospheric Retrievals of HAT-P-16b and WASP-11b/HAT-P-10b

NASA Astrophysics Data System (ADS)

McIntyre, Kathleen; Harrington, Joseph; Challener, Ryan; Lenius, Maria; Hartman, Joel D.; Bakos, Gaspar A.; Blecic, Jasmina; Cubillos, Patricio E.; Cameron, Andrew

2018-01-01

We report Bayesian atmospheric retrievals performed on the exoplanets HAT-P-16b and WASP-11b/HAT-P-10b. HAT-P-16b is a hot (equilibrium temperature 1626 ± 40 K, assuming zero Bond albedo and efficient energy redistribution), 4.19 ± 0.09 Jupiter-mass exoplanet orbiting an F8 star every 2.775960 ± 0.000003 days (Buchhave et al 2010). WASP-11b/HAT-P-10b is a cooler (1020 ± 17 K), 0.487 ± 0.018 Jupiter-mass exoplanet orbiting a K3 star every 3.7224747 ± 0.0000065 days (Bakos et al. 2009, co-discovered by West et al. 2008). We observed secondary eclipses of both planets using the 3.6 μm and 4.5 μm channels of the Spitzer Space Telescope's Infrared Array Camera (program ID 60003). We applied our Photometry for Orbits, Eclipses, and Transits (POET) code to produce normalized eclipse light curves, and our Bayesian Atmospheric Radiative Transfer (BART) code to constrain the temperature-pressure profiles and atmospheric molecular abundances of the two planets. Spitzer is operated by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. This work was supported by NASA Planetary Atmospheres grant NNX12AI69G and NASA Astrophysics Data Analysis Program grant NNX13AF38G.

The `DODO' survey - I. Limits on ultra-cool substellar and planetary-mass companions to van Maanen's star (vMa2)

NASA Astrophysics Data System (ADS)

Burleigh, M. R.; Clarke, F. J.; Hogan, E.; Brinkworth, C. S.; Bergeron, P.; Dufour, P.; Dobbie, P. D.; Levan, A. J.; Hodgkin, S. T.; Hoard, D. W.; Wachter, S.

2008-05-01

We report limits in the planetary-mass regime for companions around the nearest single white dwarf to the Sun, van Maanen's star (vMa2), from deep J-band imaging with Gemini North and Spitzer Infrared Array Camera (IRAC) mid-IR photometry. We find no resolved common proper motion companions to vMa2 at separations from 3 to 45 arcsec, at a limiting magnitude of J ~ 23. Assuming a total age for the system of 4.1 +/- 1Gyr, and utilizing the latest evolutionary models for substellar objects, this limit is equivalent to companion masses >7 +/- 1MJup(Teff ~ 300K). Taking into account the likely orbital evolution of very low mass companions in the post-main-sequence phase, these J-band observations effectively survey orbits around the white dwarf progenitor from 3 to 50au. There is no flux excess detected in any of the complimentary Spitzer IRAC mid-IR filters. We fit a white dwarf model atmosphere to the optical BVRI, JHK and IRAC photometry. The best solution gives Teff = 6030 +/- 240K, logg = 8.10 +/- 0.04 and, hence, M = 0.633 +/- 0.022Msolar. We then place a 3σ upper limit of 10 +/- 2MJup on the mass of any unresolved companion in the 4.5μm band.

Spectrum from Faint Galaxy IRAS F00183-7111

NASA Technical Reports Server (NTRS)

2003-01-01

NASA's Spitzer Space Telescope has detected the building blocks of life in the distant universe, albeit in a violent milieu. Training its powerful infrared eye on a faint object located at a distance of 3.2 billion light-years, Spitzer has observed the presence of water and organic molecules in the galaxy IRAS F00183-7111. With an active galactic nucleus, this is one of the most luminous galaxies in the universe, rivaling the energy output of a quasar. Because it is heavily obscured by dust (see visible-light image in the inset), most of its luminosity is radiated at infrared wavelengths.

The infrared spectrograph instrument onboard Spitzer breaks light into its constituent colors, much as a prism does for visible light. The image shows a low-resolution spectrum of the galaxy obtained by the spectrograph at wavelengths between 4 and 20 microns. Spectra are graphical representations of a celestial object's unique blend of light. Characteristic patterns, or fingerprints, within the spectra allow astronomers to identify the object's chemical composition and to determine such physical properties as temperature and density.

The broad depression in the center of the spectrum denotes the presence of silicates (chemically similar to beach sand) in the galaxy. An emission peak within the bottom of the trough is the chemical signature for molecular hydrogen. The hydrocarbons (orange) are organic molecules comprised of carbon and hydrogen, two of the most common elements on Earth. Since it has taken more than three billion years for the light from the galaxy to reach Earth, it is intriguing to note the presence of organics in a distant galaxy at a time when life is thought to have started forming on our home planet.

Additional features in the spectrum reveal the presence of water ice (blue), carbon dioxide ice (green) and carbon monoxide (purple) in both gas and solid forms. The magenta peak corresponds to singly ionized neon gas, a spectral line often used by astronomers as a diagnostic of star formation rates in distant galaxies.

The Spitzer spectrum is the result of only 14 minutes of integration time, highlighting the power of the infrared spectrograph to unlock the secrets of distant galaxies.

Structure of massive star forming clumps from the Red MSX Source Survey

NASA Astrophysics Data System (ADS)

Figura, Charles C.; Urquhart, J. S.; Morgan, L.

2014-01-01

We present ammonia (1,1) and (2,2) emission maps of 61 high-mass star forming regions drawn from the Red MSX Source (RMS) Survey and observed with the Green Bank Telescope's K-Band Focal Plane Array. We use these observations to investigate the spatial distribution of the environmental conditions associated with this sample of embedded massive young stellar objects (MYSOs). Ammonia is an excellent high-density tracer of star-forming regions as its hyperfine structure allows relatively simple characterisation of the molecular environment. These maps are used to measure the column density, kinetic gas temperature distributions and velocity structure across these regions. We compare the distribution of these properties to that of the associated dust and mid-infrared emission traced by the ATLASGAL 870 micron emission maps and the Spitzer GLIMPSE IRAC images. We present a summary of these results and highlight some of more interesting finds.

North Polar Surfaces of the Uranian Moons: Coated with CO2 Frost?

NASA Astrophysics Data System (ADS)

Cartwright, Richard; Emery, Joshua; Rivkin, Andy; Trilling, David; Pinilla-Alonso, Noemi

2014-12-01

We propose to investigate the near-surface composition of the Uranian moons Ariel, Umbriel, Titania, and Oberon by using the Infrared Array Camera (IRAC) onboard the Spitzer Space Telescope. Previous IRAC observations of these objects in Program 71 (2003 - 2005) indicate that the surfaces of their southern hemispheres are dominated by pure water ice (sub-observer latitudes 7 - 18 degree S). The observations we propose here are of these objects' now observable northern hemispheres (sub-observer latitudes 25 - 33 degree N). Unlike the Program 71 observations, which collected data near the end of southern summer when any seasonal CO2 frost would have migrated to the winter hemisphere, we are proposing to observe these moons at the beginning of northern summer when seasonal CO2 frost should still be present. Therefore, the 2015 - 2016 Cycle 11 opportunity window represents an ideal time frame to search for seasonal CO2 frost on these objects.

An AzTEC 1.1-mm survey for ULIRGs in the field of the Galaxy Cluster MS0451.6-0305

NASA Astrophysics Data System (ADS)

Wardlow, J. L.; Smail, Ian; Wilson, G. W.; Yun, M. S.; Coppin, K. E. K.; Cybulski, R.; Geach, J. E.; Ivison, R. J.; Aretxaga, I.; Austermann, J. E.; Edge, A. C.; Fazio, G. G.; Huang, J.; Hughes, D. H.; Kodama, T.; Kang, Y.; Kim, S.; Mauskopf, P. D.; Perera, T. A.; Scott, K. S.

2010-02-01

We have undertaken a deep (σ ~ 1.1 mJy) 1.1-mm survey of the z = 0.54 cluster MS0451.6-0305 using the AzTEC camera on the James Clerk Maxwell Telescope. We detect 36 sources with signal-to-noise ratio (S/N) >= 3.5 in the central 0.10 deg2 and present the AzTEC map, catalogue and number counts. We identify counterparts to 18 sources (50 per cent) using radio, mid-infrared, Spitzer InfraRed Array Camera (IRAC) and Submillimetre Array data. Optical, near- and mid-infrared spectral energy distributions are compiled for the 14 of these galaxies with detectable counterparts, which are expected to contain all likely cluster members. We then use photometric redshifts and colour selection to separate background galaxies from potential cluster members and test the reliability of this technique using archival observations of submillimetre galaxies. We find two potential MS0451-03 members, which, if they are both cluster galaxies, have a total star formation rate (SFR) of ~100Msolaryr-1 - a significant fraction of the combined SFR of all the other galaxies in MS0451-03. We also examine the stacked rest-frame mid-infrared, millimetre and radio emission of cluster members below our AzTEC detection limit, and find that the SFRs of mid-IR-selected galaxies in the cluster and redshift-matched field populations are comparable. In contrast, the average SFR of the morphologically classified late-type cluster population is nearly three times less than the corresponding redshift-matched field galaxies. This suggests that these galaxies may be in the process of being transformed on the red sequence by the cluster environment. Our survey demonstrates that although the environment of MS0451-03 appears to suppress star formation in late-type galaxies, it can support active, dust-obscured mid-IR galaxies and potentially millimetre-detected LIRGs.

A SPITZER SURVEY OF MID-INFRARED MOLECULAR EMISSION FROM PROTOPLANETARY DISKS. I. DETECTION RATES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pontoppidan, Klaus M.; Blake, Geoffrey A.; Meijerink, Rowin

2010-09-01

We present a Spitzer InfraRed Spectrometer search for 10-36 {mu}m molecular emission from a large sample of protoplanetary disks, including lines from H{sub 2}O, OH, C{sub 2}H{sub 2}, HCN, and CO{sub 2}. This paper describes the sample and data processing and derives the detection rate of mid-infrared molecular emission as a function of stellar mass. The sample covers a range of spectral type from early M to A, and is supplemented by archival spectra of disks around A and B stars. It is drawn from a variety of nearby star-forming regions, including Ophiuchus, Lupus, and Chamaeleon. Spectra showing strong emissionmore » lines are used to identify which lines are the best tracers of various physical and chemical conditions within the disks. In total, we identify 22 T Tauri stars with strong mid-infrared H{sub 2}O emission. Integrated water line luminosities, where water vapor is detected, range from 5 x 10{sup -4} to 9 x 10{sup -3} L{sub sun}, likely making water the dominant line coolant of inner disk surfaces in classical T Tauri stars. None of the five transitional disks in the sample show detectable gaseous molecular emission with Spitzer upper limits at the 1% level in terms of line-to-continuum ratios (apart from H{sub 2}), but the sample is too small to conclude whether this is a general property of transitional disks. We find a strong dependence on detection rate with spectral type; no disks around our sample of 25 A and B stars were found to exhibit water emission, down to 1%-2% line-to-continuum ratios, in the mid-infrared, while more than half of disks around late-type stars (M-G) show sufficiently intense water emission to be detected by Spitzer, with a detection rate approaching 2/3 for disks around K stars. Some Herbig Ae/Be stars show tentative H{sub 2}O/OH emission features beyond 20 {mu}m at the 1%-2% level, however, and one of them shows CO{sub 2} in emission. We argue that the observed differences between T Tauri disks and Herbig Ae/Be disks are due to a difference in excitation and/or chemistry depending on spectral type and suggest that photochemistry may be playing an important role in the observable characteristics of mid-infrared molecular line emission from protoplanetary disks.« less

The growing population of dark objects that have high emissivity contrast

NASA Astrophysics Data System (ADS)

Sunshine, Jessica M.; Kelley, Michael S. P.; McAdam, Margaret M.

2017-10-01

At visible and near-infrared wavelengths dark asteroids, Trojan asteroids, and cometary nuclei are largely featureless and are thus characterized and compared primarily based on differences in their spectral slopes. In contrast, in the mid-infrared a series of telescopic observations (e.g., ISO, Spitzer, SOFIA) have revealed subtle but clear silicate emissions in the 9-11 µm region. For the most part, these features are very low in spectral contrast (~5%). However, Emery et al. (2006) showed that Spitzer spectra of Trojan asteroids can have much larger spectral contrast (~10-15%) akin to cometary comae and dust in planetary disks. Similar high-contrast silicate features were found by Kelley et al. (2017) in Spitzer spectra of bare cometary nuclei. Together these results suggest the presence of fine grained and likely highly porous surfaces (Emery et al., 2006; Vernazza et al., 2012). Here we report on archival spectroscopy with the Spitzer Space Telescope that shows two mainbelt asteroids 267 Tirza (D-type; 55 km diameter) and 1284 Lativa (T/L-type; 40 km diameter) also have strong 10 µm silicate emission features. Moreover, the shapes of their silicate features match those of the other Trojan D-types; the best agreement is with 1172 Aneas. If high porosity is responsible for the enhanced spectra contrast in these objects, that porosity must now be explained for objects over an extended range of heliocentric distances, sizes, and that likely have different accretionary and impact histories.

The Growing Population of Dark Objects Inferred to Have High Surface Porosity

NASA Astrophysics Data System (ADS)

Sunshine, J. M.; Kelley, M. S. P.; McAdam, M. M.

2017-12-01

At visible and near-infrared wavelengths dark asteroids, Trojan asteroids, and cometary nuclei are largely featureless and are thus characterized and compared primarily based on differences in their spectral slopes. In contrast, in the mid-infrared a series of telescopic observations (e.g., ISO, Spitzer, SOFIA) have revealed subtle but clear silicate emissions in the 9-11 µm region. These features are mostly very low in spectral contrast ( 5%). However, Emery et al. (2006) showed that Spitzer spectra of Trojan asteroids can have much larger spectral contrast ( 10-15%) akin to cometary comae and dust in planetary disks. Similar high-contrast silicate features were found by Kelley et al. (2017) in Spitzer spectra of bare cometary nuclei. Together these results suggest the presence of fine grained and likely highly porous surfaces (Emery et al., 2006; Vernazza et al., 2012). Here we report on archival spectroscopy with the Spitzer Space Telescope that shows two mainbelt asteroids 267 Tirza (D-type; 55 km diameter) and 1284 Lativa (T/L-type; 40 km diameter) also have strong 10 µm silicate emission features. Moreover, the shapes of their silicate features match those of the other Trojan D-types. The best agreement is with 1172 Aneas. If high porosity is responsible for the enhanced spectra contrast in these objects, that porosity must now be explained for objects over an extended range of heliocentric distances, sizes, and that likely have different accretionary and impact histories.

A SYSTEMATIC SEARCH FOR THE SPECTRA WITH FEATURES OF CRYSTALLINE SILICATES IN THE SPITZER IRS ENHANCED PRODUCTS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Rui; Luo, Ali; Liu, Jiaming

2016-06-01

The crystalline silicate features are mainly reflected in infrared bands. The Spitzer Infrared Spectrograph (IRS) collected numerous spectra of various objects and provided a big database to investigate crystalline silicates in a wide range of astronomical environments. We apply the manifold ranking algorithm to perform a systematic search for the spectra with crystalline silicate features in the Spitzer IRS Enhanced Products available. In total, 868 spectra of 790 sources are found to show the features of crystalline silicates. These objects are cross-matched with the SIMBAD database as well as with the Large Sky Area Multi-object Fiber Spectroscopic Telescope (LAMOST)/DR2. Themore » average spectrum of young stellar objects shows a variety of features dominated either by forsterite or enstatite or neither, while the average spectrum of evolved objects consistently present dominant features of forsterite in AGB, OH/IR, post-AGB, and planetary nebulae. They are identified optically as early-type stars, evolved stars, galaxies and so on. In addition, the strength of spectral features in typical silicate complexes is calculated. The results are available through CDS for the astronomical community to further study crystalline silicates.« less

The AGN fraction of submm-selected galaxies and contributions to the submm/mm-wave extragalactic background light

NASA Astrophysics Data System (ADS)

Serjeant, S.; Negrello, M.; Pearson, C.; Mortier, A.; Austermann, J.; Aretxaga, I.; Clements, D.; Chapman, S.; Dye, S.; Dunlop, J.; Dunne, L.; Farrah, D.; Hughes, D.; Lee, H.-M.; Matsuhara, H.; Ibar, E.; Im, M.; Jeong, W.-S.; Kim, S.; Oyabu, S.; Takagi, T.; Wada, T.; Wilson, G.; Vaccari, M.; Yun, M.

2010-05-01

We present a comparison of the SCUBA half degree extragalactic survey (SHADES) at 450 μm, 850 μm and 1100 μm with deep guaranteed time 15 μm AKARI FU-HYU survey data and Spitzer guaranteed time data at 3.6-24 μm in the Lockman hole east. The AKARI data was analysed using bespoke software based in part on the drizzling and minimum-variance matched filtering developed for SHADES, and was cross-calibrated against ISO fluxes. Our stacking analyses find AKARI 15 μm galaxies with ⪆200 μJy contribute >10% of the 450 μm background, but only <4% of the 1100 μm background, suggesting that different populations contribute at mm-wavelengths. We confirm our earlier result that the ultra-deep 450 μm SCUBA-2 cosmology survey will be dominated by populations already detected by AKARI and Spitzer mid-infrared surveys. The superb mid-infrared wavelength coverage afforded by combining Spitzer and AKARI photometry is an excellent diagnostic of AGN contributions, and we find that (23-52)% of submm-selected galaxies have AGN bolometric fractions fAGN > 0.3.

Omega Centauri Looks Radiant in Infrared

NASA Image and Video Library

2008-04-10

A cluster brimming with millions of stars glistens like an iridescent opal in this image from NASA Spitzer Space Telescope. Called Omega Centauri, the sparkling orb of stars is like a miniature galaxy.

Galactic Metropolis

NASA Image and Video Library

2013-12-18

The collection of red dots seen here show one of several very distant galaxy clusters discovered by combining ground-based optical data from the NOAO Kitt Peak National Observatory with infrared data from NASA Spitzer Space Telescope.

Black Hole Jets Make Shock Waves

NASA Image and Video Library

2014-07-02

A composite image of the spiral galaxy NGC 4258 showing X-ray emission observed with NASA Chandra X-ray Observatory blue and infrared emission observed with NASA Spitzer Space Telescope red and green.

Observations of Disks around Brown Dwarfs in the TW Hydra Association with the Spitzer Infrared Spectrograph

NASA Astrophysics Data System (ADS)

Morrow, A. L.; Luhman, K. L.; Espaillat, C.; D'Alessio, P.; Adame, L.; Calvet, N.; Forrest, W. J.; Sargent, B.; Hartmann, L.; Watson, D. M.; Bohac, C. J.

2008-04-01

Using SpeX at the NASA Infrared Telescope Facility and the Spitzer Infrared Spectrograph, we have obtained infrared spectra from 0.7 to 40 μm for three young brown dwarfs in the TW Hydra association (τ ~ 10 Myr), 2MASSW J1207334-393254, 2MASSW J1139511-315921, and SSSPM J1102-3431. The spectral energy distribution for 2MASSW J1139511-315921 is consistent with a stellar photosphere for the entire wavelength range of our data, whereas the other two objects exhibit significant excess emission at λ > 5μm. We are able to reproduce the excess emission from each brown dwarf using our models of irradiated accretion disks. According to our model fits, both disks have experienced a high degree of dust settling. We also find that silicate emission at 10 and 20 μm is absent from the spectra of these disks, indicating that grains in the upper disk layers have grown to sizes larger than ~5 μm. Both of these characteristics are consistent with previous observations of decreasing silicate emission with lower stellar masses and older ages. These trends suggest that either (1) the growth of dust grains, and perhaps planetesimal formation, occurs faster in disks around brown dwarfs than in disks around stars or (2) the radii of the mid-IR-emitting regions of disks are smaller for brown dwarfs than for stars, and grains grow faster at smaller disk radii. Finally, we note the possible detection of an unexplained emission feature near 14 μm in the spectra of both of the disk-bearing brown dwarfs. Based on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory at the California Institute of Technology under NASA contract 1407.

Charting Ingredients for Life

NASA Technical Reports Server (NTRS)

2005-01-01

[figure removed for brevity, see original site] Figure 1: Spectrum Charts Light from a Faraway Galaxy

This graph, or spectrum, charts light from a faraway galaxy located 10 billion light years from Earth. It tracks mid-infrared light from an extremely luminous galaxy when the universe was only 1/4 of its current age.

Spectra are created when an instrument called a spectrograph spreads light out into its basic parts, like a prism turning sunlight into a rainbow. They reveal the signatures, or 'fingerprints,' of molecules that make up a galaxy and contribute to its light.

Spitzer's infrared spectrometer identified characteristic fingerprints of complex organic molecules called polycyclic aromatic hydrocarbons, illustrated in the artist's concept in the inset. These large molecules comprised of carbon and hydrogen, are considered among the building blocks of life.

Scientists determined it took 10 billion years for photons from this galaxy to reach Spitzer's infrared eyes. These complex carbon and hydrogen molecules are from a young galaxy which is undergoing intense star formation, at the time the universe was only 3.5 billion years old.

These distant galaxies with enormous amounts of gas being converted into young stars are some of the most luminous objects in the sky. Enshrouded by dust, they are only faint, inconspicuous little dots in optical images. They are as bright as 10 trillion suns put together and 10 times brighter than starburst galaxies seen in our local universe.

This prompts a fascinating question as to what physical process is driving such enormous energy production in these galaxies when the universe is so young.

These data were taken by Spitzer's infrared spectrograph in August and September 2004.

Observation and Analysis of Secondary Eclipses of WASP-32b

NASA Astrophysics Data System (ADS)

Garland, Justin; Harrington, Joesph; Cubillos, Patricio; Blecic, Jasmina; Foster, Andrew S.; Bowman, Matthew O.; Maxted, Pierre F. L.

2014-11-01

We report two Spitzer secondary eclipses of the exoplanet WASP-32b. Discovered by Maxted et al. (2010), this hot-Jupiter planet has a mass of 3.6 +/- 0.07 Mj, a radius of 1.18 +/- 0.07 Rj, and an orbital period of 2.71865 +/- 0.00008 days around a G-type star. We observed two secondary eclipses in the 3.6 micron and 4.5 micron channels using the Spitzer Space Telescope in 2010 as a part of the Spitzer Exoplanet Target of Opportunity program (program 60003). We present eclipse-depth measurements, estimates of infrared brightness temperatures, and refinements of orbital parameters for WASP-32b from our eclipse measurements as well as amatuer and professional data. Spitzer is operated by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. This work was supported by NASA Planetary Atmospheres grant NNX12AI69G and NASA Astrophysics Data Analysis Program grant NNX13AF38G. JB holds a NASA Earth and Space Science Fellowship.

Spitzer-IRS Spectroscopic Studies of Oxygen-Rich Asymptotic Giant Branch Star and Red Supergiant Star Dust Properties

NASA Astrophysics Data System (ADS)

Sargent, Benjamin A.; Srinivasan, Sundar; Speck, Angela; Volk, Kevin; Kemper, Ciska; Reach, William T.; Lagadec, Eric; Bernard, Jean-Philippe; McDonald, Iain; Meixner, Margaret

2015-01-01

We analyze the dust emission features seen in Spitzer Space Telescope Infrared Spectrograph (IRS) spectra of Oxygen-rich (O-rich) asymptotic giant branch (AGB) and red supergiant (RSG) stars. The spectra come from the Spitzer Legacy program SAGE-Spectroscopy (PI: F. Kemper) and other archival Spitzer-IRS programs. The broad 10 and 20 micron emission features attributed to amorphous dust of silicate composition seen in the spectra show evidence for systematic differences in the centroid of both emission features between O-rich AGB and RSG populations. Radiative transfer modeling using the GRAMS grid of models of AGB and RSG stars suggests that the centroid differences are due to differences in dust properties. We present an update of our investigation of differences in dust composition, size, shape, etc that might be responsible for these spectral differences. We explore how these differences may arise from the different circumstellar environments around RSG and O-rich AGB stars. BAS acknowledges funding from NASA ADAP grant NNX13AD54G.

Spitzer-IRS Spectroscopic Studies of the Properties of Dust from Oxygen-Rich Asymptotic Giant Branch and Red Supergiant Stars

NASA Astrophysics Data System (ADS)

Sargent, Benjamin A.; Speck, A.; Volk, K.; Kemper, C.; Reach, W. T.; Lagadec, E.; Bernard, J.; McDonald, I.; Meixner, M.; Srinivasan, S.

2014-01-01

We analyze the dust emission features seen in Spitzer Space Telescope Infrared Spectrograph (IRS) spectra of Oxygen-rich (O-rich) asymptotic giant branch (AGB) and red supergiant (RSG) stars. The spectra come from the Spitzer Legacy program SAGE-Spectroscopy (PI: F. Kemper) and other archival Spitzer-IRS programs. The broad 10 and 20 micron emission features attributed to amorphous dust of silicate composition seen in the spectra show evidence for systematic differences in the centroid of both emission features between O-rich AGB and RSG populations. Radiative transfer modeling using the GRAMS grid of models of AGB and RSG stars suggests that the centroid differences are due to differences in dust properties. We investigate differences in dust composition, size, shape, etc that might be responsible for these spectral differences. We explore how these differences may arise from the different circumstellar environments around RSG and O-rich AGB stars. BAS acknowledges funding from NASA ADAP grant NNX13AD54G.

Studying Galaxy Formation with the Hubble, Spitzer and James Webb Space Telescopes

NASA Technical Reports Server (NTRS)

Gardner, Jonathan P.

2007-01-01

The deepest optical to infrared observations of the universe include the Hubble Deep Fields, the Great Observatories Origins Deep Survey and the recent Hubble Ultra-Deep Field. Galaxies are seen in these surveys at redshifts 2x3, less than 1 Gyr after the Big Bang, at the end of a period when light from the galaxies has reionized Hydrogen in the inter-galactic medium. These observations, combined with theoretical understanding, indicate that the first stars and galaxies formed at z>lO, beyond the reach of the Hubble and Spitzer Space Telescopes. To observe the first galaxies, NASA is planning the James Webb Space Telescope (JWST), a large (6.5m), cold (<50K), infrared-optimized observatory to be launched early in the next decade into orbit around the second Earth- Sun Lagrange point. JWST will have four instruments: The Near-Infrared Camera, the Near-Infrared multi-object Spectrograph, and the Tunable Filter Imager will cover the wavelength range 0.6 to 5 microns, while the Mid-Infrared Instrument will do both imaging and spectroscopy from 5 to 28.5 microns. In addition to JWST's ability to study the formation and evolution of galaxies, I will also briefly review its expected contributions to studies of the formation of stars and planetary systems.

Studying Galaxy Formation with the Hubble, Spitzer and James Webb Space Telescopes

NASA Technical Reports Server (NTRS)

Gardner, Jonathan F.; Barbier, L. M.; Barthelmy, S. D.; Cummings, J. R.; Fenimore, E. E.; Gehrels, N.; Hullinger, D. D.; Markwardt, C. B.; Palmer, D. M.; Parsons, A. M.;

Studying Galaxy Formation with the Hubble, Spitzer and James Webb Space Telescopes

NASA Technical Reports Server (NTRS)

Gardner, Jonathan P.

2007-01-01

The deepest optical to infrared observations of the universe include the Hubble Deep Fields, the Great Observatories Origins Deep Survey and the recent Hubble Ultra-Deep Field. Galaxies are seen in these surveys at redshifts z>6, less than 1 Gyr after the Big Bang, at the end of a period when light from the galaxies has reionized Hydrogen in the inter-galactic medium. These observations, combined with theoretical understanding, indicate that the first stars and galaxies formed at z>10, beyond the reach of the Hubble and Spitzer Space Telescopes. To observe the first galaxies, NASA is planning the James Webb Space Telescope (JWST), a large (6.5m), cold (<50K), infrared-optimized observatory to be launched early in the next decade into orbit around the second Earth- Sun Lagrange point. JWST will have four instruments: The Near-Infrared Camera, the Near-Infrared multi-object Spectrograph, and the Tunable Filter Imager will cover the wavelength range 0.6 to 5 microns, while the Mid-Infrared Instrument will do both imaging and spectroscopy from 5 to 28.5 microns. In addition to JWST's ability to study the formation and evolution of galaxies, I will also briefly review its expected contributions to studies of the formation of stars and planetary systems.

The Gaseous Disks of Young Stellar Objects

NASA Technical Reports Server (NTRS)

Glassgold, A. E.

2006-01-01

Disks represent a crucial stage in the formation of stars and planets. They are novel astrophysical systems with attributes intermediate between the interstellar medium and stars. Their physical properties are inhomogeneous and are affected by hard stellar radiation and by dynamical evolution. Observing disk structure is difficult because of the small sizes, ranging from as little as 0.05 AU at the inner edge to 100-1000 AU at large radial distances. Nonetheless, substantial progress has been made by observing the radiation emitted by the dust from near infrared to mm wavelengths, i.e., the spectral energy distribution of an unresolved disk. Many fewer results are available for the gas, which is the main mass component of disks over much of their lifetime. The inner disk gas of young stellar objects (henceforth YSOs) have been studied using the near infrared rovibrational transitions of CO and a few other molecules, while the outer regions have been explored with the mm and sub-mm lines of CO and other species. Further progress can be expected in understanding the physical properties of disks from observations with sub-mm arrays like SMA, CARMA and ALMA, with mid infrared measurements using Spitzer, and near infrared spectroscopy with large ground-based telescopes. Intense efforts are also being made to model the observations using complex thermal-chemical models. After a brief review of the existing observations and modeling results, some of the weaknesses of the models will be discussed, including the absence of good laboratory and theoretical calculations for essential microscopic processes.

Short-Wavelength Infrared Views of Messier 81

NASA Image and Video Library

2003-12-18

The magnificent spiral arms of the nearby galaxy Messier 81 are highlighted in this NASA Spitzer Space Telescope image. Located in the northern constellation of Ursa Major which also includes the Big Dipper.

The Case of the Disappearing Continent

NASA Image and Video Library

2011-02-10

This infrared image from NASA Spitzer Space Telescope shows a swirling landscape of stars known as the North America nebula. Clusters of young stars about one million years old can be found throughout the image.

Massive Star Makes Waves

NASA Image and Video Library

2012-12-18

The giant star Zeta Ophiuchi, a young, large and hot star located around 370 light-years away, is having a hocking effect on the surrounding dust clouds in this infrared image from NASA Spitzer Space Telescope.

An Extended Stellar Family

NASA Image and Video Library

2011-02-10

This visible light/infrared image from NASA Spitzer Space Telescope shows a swirling landscape of stars known as the North America nebula. Clusters of young stars about one million years old can be found throughout the image.

Smokin Hot Galaxy animation

NASA Image and Video Library

2006-03-16

This infrared image from NASA Spitzer Space Telescope shows a galaxy that appears to be sizzling hot, with huge plumes of smoke swirling around it. The galaxy is known as Messier 82 or the Cigar galaxy.

Cosmic Epic Unfolds in Infrared

NASA Image and Video Library

2007-01-09

This majestic view taken by NASA Spitzer Space Telescope tells an untold story of life and death in the Eagle nebula, an industrious star-making factory located 7,000 light-years away in the Serpens constellation.

First Results from the AKARI FU-HYU Mission Program

NASA Astrophysics Data System (ADS)

Pearson, C.; Serjeant, S.; Takagi, T.; Jeong, W.-S.; Negrello, M.; Matsuhara, H.; Wada, T.; Oyabu, S.; Lee, H. M.; Im, M.

2009-12-01

The AKARI FU-HYU mission program has carried out mid-infrared imaging of several well studied Spitzer fields. This imaging fills in the wavelength coverage lacking from the Spitzer surveys and gives an extremely high scientific return for minimal input for AKARI. We select fields already rich in multi-wavelength data from radio to X-ray wavelengths and present the results from our initial analysis in the GOODS-N field. We utilize the comprehansive multiwavelength coverage in the GOODS-N field to produce a multiwavelength catalogue from infrared to ultraviolet wavelengths including photometric redshifts. Using the FU-HYU catalogue we present colour-colour diagrams that map the passage of PAH features through our observation bands. These colour-colours diagrams are used as tools to extract anomalous colour populations, in particular a population of Silicate Break galaxies from the GOODS-N field.

Advancing Absolute Calibration for JWST and Other Applications

NASA Astrophysics Data System (ADS)

Rieke, George; Bohlin, Ralph; Boyajian, Tabetha; Carey, Sean; Casagrande, Luca; Deustua, Susana; Gordon, Karl; Kraemer, Kathleen; Marengo, Massimo; Schlawin, Everett; Su, Kate; Sloan, Greg; Volk, Kevin

2017-10-01

We propose to exploit the unique optical stability of the Spitzer telescope, along with that of IRAC, to (1) transfer the accurate absolute calibration obtained with MSX on very bright stars directly to two reference stars within the dynamic range of the JWST imagers (and of other modern instrumentation); (2) establish a second accurate absolute calibration based on the absolutely calibrated spectrum of the sun, transferred onto the astronomical system via alpha Cen A; and (3) provide accurate infrared measurements for the 11 (of 15) highest priority stars with no such data but with accurate interferometrically measured diameters, allowing us to optimize determinations of effective temperatures using the infrared flux method and thus to extend the accurate absolute calibration spectrally. This program is integral to plans for an accurate absolute calibration of JWST and will also provide a valuable Spitzer legacy.

Spectroscopic Infrared Extinction Mapping as a Probe of Grain Growth in IRDCs

NASA Astrophysics Data System (ADS)

Lim, Wanggi; Carey, Sean J.; Tan, Jonathan C.

2015-11-01

We present spectroscopic tests of MIR to FIR extinction laws in IRDC G028.36+00.07, a potential site of massive star and star cluster formation. Lim & Tan developed methods of FIR extinction mapping of this source using Spitzer-MIPS 24 μm and Herschel-PACS 70 μm images, and by comparing to MIR Spitzer-IRAC 3-8 μm extinction maps, found tentative evidence for grain growth in the highest mass surface density regions. Here we present results of spectroscopic infrared extinction mapping using Spitzer-IRS (14-38 μm) data of the same Infrared dark cloud (IRDC). These methods allow us to first measure the SED of the diffuse Galactic interstellar medium that is in the foreground of the IRDC. We then carry out our primary investigation of measuring the MIR to FIR opacity law and searching for potential variations as a function of mass surface density within the IRDC. We find relatively flat, featureless MIR-FIR opacity laws that lack the ˜12 and ˜35 μm features associated with the thick water ice mantle models of Ossenkopf & Henning. Their thin ice mantle models and the coagulating aggregate dust models of Ormel et al. are a generally better match to the observed opacity laws. We also find evidence for generally flatter MIR to FIR extinction laws as mass surface density increases, strengthening the evidence for grain and ice mantle growth in higher density regions.

A Search to Uncover the Infrared Excess (IRXS) Sources in the Spitzer Enhanced Imaging Products (SEIP) Catalog

NASA Astrophysics Data System (ADS)

Rowe, Jamie Lynn; Duranko, Gary; Gorjian, Varoujan; Lineberger, Howard; Orr, Laura; Adewole, Ayomikun; Bradford, Eric; Douglas, Alea; Kohl, Steven; Larson, Lillia; Lascola, Gus; Orr, Quinton; Scott, Mekai; Walston, Joseph; Wang, Xian

2018-01-01

The Spitzer Enhanced Imaging Products catalog (SEIP) is a collection of nearly 42 million point sources obtained by the Spitzer Space Telescope during its 5+ year cryogenic mission. Strasburger et al (2014) isolated sources with a signal-to-noise ratio (SNR) >10 in five infrared (IR) wavelength channels (3.6, 4.5, 5.8, 8 and 24 microns) to begin a search for sources with infrared excess (IRXS). They found 76 objects that were never catalogued before. Based on this success, we intend to dig deeper into the catalog in an attempt to find more IRXS sources, specifically by lowering the SNR on the 3.6, 4.5, and 24 micron channels. The ultimate goal is to use this large sample to seek rare astrophysical sources that are transitional in nature and evolutionarily very important.Our filtering of the database at SNR > 5 yielded 461,000 sources. This was further evaluated and reduced to only the most interesting based on source location on a [3.6]-[4.5] vs [4.5]-[24] color-color diagram. We chose a sample of 985 extreme IRXS sources for further inspection. All of these candidate sources were visually inspected and cross-referenced against known sources in existing databases, resulting in a list of highly reliable IRXS sources.These sources will prove important in the study of galaxy and stellar evolution, and will serve as a starting point for further investigation.

SPECTROSCOPIC INFRARED EXTINCTION MAPPING AS A PROBE OF GRAIN GROWTH IN IRDCs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lim, Wanggi; Carey, Sean J.; Tan, Jonathan C.

We present spectroscopic tests of MIR to FIR extinction laws in IRDC G028.36+00.07, a potential site of massive star and star cluster formation. Lim and Tan developed methods of FIR extinction mapping of this source using Spitzer-MIPS 24 μm and Herschel-PACS 70 μm images, and by comparing to MIR Spitzer-IRAC 3–8 μm extinction maps, found tentative evidence for grain growth in the highest mass surface density regions. Here we present results of spectroscopic infrared extinction mapping using Spitzer-IRS (14–38 μm) data of the same Infrared dark cloud (IRDC). These methods allow us to first measure the SED of the diffusemore » Galactic interstellar medium that is in the foreground of the IRDC. We then carry out our primary investigation of measuring the MIR to FIR opacity law and searching for potential variations as a function of mass surface density within the IRDC. We find relatively flat, featureless MIR–FIR opacity laws that lack the ∼12 and ∼35 μm features associated with the thick water ice mantle models of Ossenkopf and Henning. Their thin ice mantle models and the coagulating aggregate dust models of Ormel et al. are a generally better match to the observed opacity laws. We also find evidence for generally flatter MIR to FIR extinction laws as mass surface density increases, strengthening the evidence for grain and ice mantle growth in higher density regions.« less

Shadows and Dust: Mid-Infrared Extinction Mapping of the Initial Conditions of Massive Star and Star Cluster Formation

NASA Astrophysics Data System (ADS)

Tan, Jonathan

We describe a research plan to develop and extend the mid-infrared (MIR) extinction mapping technique presented by Butler & Tan (2009), who studied Infrared Dark Clouds (IRDCs) using Spitzer Space Telescope Infrared Array Camera (IRAC) 8 micron images. This method has the ability to probe the detailed spatial structure of very high column density regions, i.e. the gas clouds thought to represent the initial conditions for massive star and star cluster formation. We will analyze the data Spitzer obtained at other wavelengths, i.e. the IRAC bands at 3.6, 4.5 and 5.8 microns, and the Multiband Imaging Photometer (MIPS) bands, especially at 24 microns. This will allow us to measure the dust extinction law across the MIR and search for evidence of dust grain evolution, e.g. grain growth and ice mantle formation, as a function of gas density and column density. We will also study the detailed structure of the extinction features, including individual cores that may form single stars or close binaries, especially focusing on those cores that may form massive stars. By studying independent dark cores in a given IRDC, we will be able to test if they have a common minimum observed intensity, which we will then attribute to the foreground. This is a new method that should allow us to more accurately map distant, high column density IRDCs, probing more extreme regimes of star formation. We will combine MIR extinction mapping, which works best at high column densities, with near- IR mapping based on 2MASS images of star fields, which is most useful at lower columns that probe the extended giant molecular cloud structure. This information is crucial to help understand the formation process of IRDCs, which may be the rate limiting step for global galactic star formation rates. We will use our new extinction mapping methods to analyze large samples of IRDCs and thus search the Galaxy for the most extreme examples of high column density cores and assess the global star formation efficiency in dense gas. We will estimate the ability of future NASA missions, such as JWST, to carry out MIR extinction mapping science. We will develop the results of this research into an E/PO presentation to be included in the various public outreach events organized and courses taught by the PI.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vaghmare, Kaustubh; Kembhavi, Ajit; Barway, Sudhanshu, E-mail: kaustubh@iucaa.ernet.in, E-mail: akk@iucaa.ernet.in, E-mail: barway@saao.ac.za

In this Letter, we present a systematic study of lenticular (S0) galaxies based on mid-infrared imaging data on 185 objects taken using the Spitzer Infrared Array Camera. We identify the S0s hosting pseudobulges based on the position of the bulge on the Kormendy diagram and the Sersic index of the bulge. We find that pseudobulges preferentially occur in the fainter luminosity class (defined as having total K-band absolute magnitude M{sub K} fainter than -22.66 in the AB system). We present relations between bulge and disk parameters obtained as a function of the bulge type. The disks in the pseudobulge hostingmore » galaxies are found to have distinct trends on the r{sub e}-r{sub d} and {mu}{sub d}(0)-r{sub d} correlations compared to those in galaxies with classical bulges. We show that the disks of pseudobulge hosts possess on average a smaller scale length and have a fainter central surface brightness than their counterparts occurring in classical bulge hosting galaxies. The differences found for discs in pseudobulge and classical bulge hosting galaxies may be a consequence of the different processes creating the central mass concentrations.« less

History of Hubble Space Telescope (HST)

NASA Image and Video Library

2003-06-09

The razor sharp eye of the Hubble Space Telescope (HST) easily resolves the Sombrero galaxy, Messier 104 (M104). 50,000 light-years across, the galaxy is located 28 million light-years from Earth at the southern edge of the rich Virgo cluster of galaxies. Equivalent to 800 billion suns, Sombrero is one of the most massive objects in that group. The hallmark of Sombrero is a brilliant white, bulbous core encircled by the thick dust lanes comprising the spiral structure of the galaxy. As seen from Earth, the galaxy is tilted nearly edge-on. We view it from just six degrees north of its equatorial plane. This rich system of globular clusters is estimated to be nearly 2,000 in number which is 10 times as many as in our Milky Way galaxy. Similar to the clusters in the Milky Way, the ages range from 10-13 billion years old. Embedded in the bright core of M104 is a smaller disk, which is tilted relative to the large disk. The HST paired with the Spitzer infrared telescope, offers this striking composite capturing the magnificence of the Sombrero galaxy. In the Hubble view, the galaxy resembles a broad-rimmed Mexican hat, whereas in the Spitzer striking infrared view, the galaxy looks more like a bulls eye. The full view provided by Spitzer shows the disk is warped, which is often the result of a gravitational encounter with another galaxy, and clumpy areas spotted in the far edges of the ring indicate young star forming regions. Spitzer detected infrared emission not only from the ring, but from the center of the galaxy as well, where there is a huge black hole believed to be a billion times more massive than our Sun. The Marshall Space Flight Center (MSFC) had responsibility for design, development, and construction of the HST.

Constraining the Origin and Heating Mechanism of Dust in Type IIn Supernovae

NASA Astrophysics Data System (ADS)

Fox, Ori; Skrutskie, Michael; Chevalier, Roger; Moseley, Samuel Harvey

2011-05-01

More than any other supernova subclass, Type IIn supernovae tend to exhibit late-time (>100 days) infrared emission from warm dust. Identifying the origin and heating mechanism of the dust provides an important probe of the supernova explosion, circumstellar environment, and progenitor system. Yet mid-infrared observations, which span the peak of the thermal emission, are rare. Two years ago, we executed a warm Spitzer survey (P60122) of sixty-eight Type IIn events from the past ten years. The survey uncovered nine supernovae with unreported late-time infrared excesses, in some cases more than 5 years post-explosion. From this single epoch of data, and ground-based optical data, we have determined the likely origin of the mid-infrared emission to be pre-existing dust that is continuously heated by optical emission generated by ongoing circumstellar interaction between the forward shock and circumstellar medium. Furthermore, we noticed an emerging trend suggests these supernovae ``turn off'' at ~1000-2000 days post-discovery once the forward shock overruns the dust shell. Now is the ideal time to build upon this work with a second epoch of observations, which will be necessary to constrain our models. If we catch even a single supernova turning off between the first and second epochs of observation, we will be able to both measure the size of the circumstellar dust shell and characterize of the supernova progenitor system. We can obtain all the necessary data in only 9.3 hours of observation. Our team has extensive experience in infrared supernovae observations. We have already published two papers on one Type IIn supernovae (SN 2005ip) and authored two successful proposal for Spitzer observations of this subclass. This is an ideal application for the Spitzer warm mission, as the 3.6 and 4.5 micron bands span the peak of the thermal emission and provide the necessary constraints on the dust temperature, mass, and luminosity.

SpS1-The Spitzer atlas of stellar spectra

NASA Astrophysics Data System (ADS)

Ardila, David R.; Makowiecki, W.; van Dyk, S.; Song, I.; Stauffer, J.; Rho, J.; Fajardo-Acosta, S.; Hoard, D. W.; Wachter, S.

2010-11-01

We present Spitzer Space Telescope spectra of 147 stars (R~64 - 128, λλ = 5 - 35 μm, S/N~100) covering most spectral and luminosity classes within the HR diagram. The spectra are available from the NASA/IPAC Infrared Science Archive (IRSA) and from the first author's webpage (http://web.ipac.caltech.edu/staff/ardila/Atlas/). The Atlas contains spectra of ‘typical’ stars, which may serve to refine galactic synthesis models, study stellar atmospheres, and establish a legacy for future IR missions, such as JWST.

Pink Pleiades

NASA Image and Video Library

2007-04-16

The Seven Sisters, also known as the Pleiades star cluster, seem to float on a bed of feathers in a new infrared image from NASA Spitzer Space Telescope. Clouds of dust sweep around the stars, swaddling them in a cushiony veil.

Infrared Coronet Cluster

NASA Image and Video Library

2007-09-13

This image from NASA Spitzer Space Telescope shows young stars plus diffuse emission from dust. The Corona Australis region containing, at its heart, the Coronet cluster is one of the nearest and most active regions of ongoing star formation.

Bulgeless Galaxy Hides Black Hole

NASA Image and Video Library

2014-03-26

The galaxy NGC 4395 is shown here in infrared light, captured by NASA Spitzer Space Telescope. This dwarf galaxy is relatively small in comparison with our Milky Way galaxy, which is nearly 1,000 times more massive.

Early-stage young stellar objects in the Small Magellanic Cloud

NASA Astrophysics Data System (ADS)

Oliveira, J. M.; van Loon, J. Th.; Sloan, G. C.; Sewiło, M.; Kraemer, K. E.; Wood, P. R.; Indebetouw, R.; Filipović, M. D.; Crawford, E. J.; Wong, G. F.; Hora, J. L.; Meixner, M.; Robitaille, T. P.; Shiao, B.; Simon, J. D.

2013-02-01

We present new observations of 34 young stellar object (YSO) candidates in the Small Magellanic Cloud (SMC). The photometric selection required sources to be bright at 24 and 70 μm (to exclude evolved stars and galaxies). The anchor of the analysis is a set of Spitzer Infrared Spectrograph (IRS) spectra, supplemented by ground-based 3-5 μm spectra, Spitzer Infrared Array Camera and Multiband Imaging Photometer for Spitzer photometry, near-infrared (IR) imaging and photometry, optical spectroscopy and radio data. The sources' spectral energy distributions and spectral indices are consistent with embedded YSOs; prominent silicate absorption is observed in the spectra of at least 10 sources, silicate emission is observed towards four sources. Polycyclic aromatic hydrocarbon (PAH) emission is detected towards all but two sources. Based on band ratios (in particular the strength of the 11.3-μm and the weakness of the 8.6-μm bands) PAH emission towards SMC YSOs is dominated by predominantly small neutral grains. Ice absorption is observed towards 14 sources in the SMC. The comparison of H2O and CO2 ice column densities for SMC, Large Magellanic Cloud and Galactic samples suggests that there is a significant H2O column density threshold for the detection of CO2 ice. This supports the scenario proposed by Oliveira et al., where the reduced shielding in metal-poor environments depletes the H2O column density in the outer regions of the YSO envelopes. No CO ice is detected towards the SMC sources. Emission due to pure rotational 0-0 transitions of molecular hydrogen is detected towards the majority of SMC sources, allowing us to estimate rotational temperatures and H2 column densities. All but one source are spectroscopically confirmed as SMC YSOs. Based on the presence of ice absorption, silicate emission or absorption and PAH emission, the sources are classified and placed in an evolutionary sequence. Of the 33 YSOs identified in the SMC, 30 sources populate different stages of massive stellar evolution. The presence of ice- and/or silicate-absorption features indicates sources in the early embedded stages; as a source evolves, a compact H ii region starts to emerge, and at the later stages the source's IR spectrum is completely dominated by PAH and fine-structure emission. The remaining three sources are classified as intermediate-mass YSOs with a thick dusty disc and a tenuous envelope still present. We propose one of the SMC sources is a D-type symbiotic system, based on the presence of Raman, H and He emission lines in the optical spectrum, and silicate emission in the IRS spectrum. This would be the first dust-rich symbiotic system identified in the SMC.

Nursery of Giants

NASA Image and Video Library

2004-04-13

Hidden behind a shroud of dust in the constellation Cygnus is a stellar nursery called DR21, which is giving birth to some of the most massive stars in our galaxy. Visible light images reveal no trace of this interstellar cauldron because of heavy dust obscuration. In fact, visible light is attenuated in DR21 by a factor of more than 10,000,000,000,000,000,000,000,000,000,000,000,000,000 (ten thousand trillion heptillion). New images from NASA's Spitzer Space Telescope allow us to peek behind the cosmic veil and pinpoint one of the most massive natal stars yet seen in our Milky Way galaxy. The never-before-seen star is 100,000 times as bright as the Sun. Also revealed for the first time is a powerful outflow of hot gas emanating from this star and bursting through a giant molecular cloud. This image is a large-scale mosaic assembled from individual photographs obtained with the InfraRed Array Camera (IRAC) aboard Spitzer. The image covers an area about two times that of a full moon. The mosaic is a composite of images obtained at mid-infrared wavelengths of 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange) and 8 microns (red). The brightest infrared cloud near the top center corresponds to DR21, which presumably contains a cluster of newly forming stars at a distance of 10,000 light-years. Protruding out from DR21 toward the bottom left of the image is a gaseous outflow (green), containing both carbon monoxide and molecular hydrogen. Data from the Spitzer spectrograph, which breaks light into its constituent individual wavelengths, indicate the presence of hot steam formed as the outflow heats the surrounding molecular gas. Outflows are physical signatures of processes that create supersonic beams, or jets, of gas. They are usually accompanied by discs of material around the new star, which likely contain the materials from which future planetary systems are formed. Additional newborn stars, depicted in green, can be seen surrounding the DR21 region. The red filaments stretching across this image denote the presence of polycyclic aromatic hydrocarbons. These organic molecules, comprised of carbon and hydrogen, are excited by surrounding interstellar radiation and become luminescent at wavelengths near 8.0 microns. The complex pattern of filaments is caused by an intricate combination of radiation pressure, gravity and magnetic fields. The result is a tapestry in which winds, outflows and turbulence move and shape the interstellar medium. To the lower left of the mosaic is a large bubble of gas and dust, which may represent the remnants of a past generation of stars. http://photojournal.jpl.nasa.gov/catalog/PIA05732

Nursery of Giants

NASA Technical Reports Server (NTRS)

2004-01-01

Hidden behind a shroud of dust in the constellation Cygnus is a stellar nursery called DR21, which is giving birth to some of the most massive stars in our galaxy. Visible light images reveal no trace of this interstellar cauldron because of heavy dust obscuration. In fact, visible light is attenuated in DR21 by a factor of more than 10,000,000,000,000,000,000,000,000,000,000,000,000,000 (ten thousand trillion heptillion).

New images from NASA's Spitzer Space Telescope allow us to peek behind the cosmic veil and pinpoint one of the most massive natal stars yet seen in our Milky Way galaxy. The never-before-seen star is 100,000 times as bright as the Sun. Also revealed for the first time is a powerful outflow of hot gas emanating from this star and bursting through a giant molecular cloud.

This image is a large-scale mosaic assembled from individual photographs obtained with the InfraRed Array Camera (IRAC) aboard Spitzer. The image covers an area about two times that of a full moon. The mosaic is a composite of images obtained at mid-infrared wavelengths of 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange) and 8 microns (red). The brightest infrared cloud near the top center corresponds to DR21, which presumably contains a cluster of newly forming stars at a distance of 10,000 light-years.

Protruding out from DR21 toward the bottom left of the image is a gaseous outflow (green), containing both carbon monoxide and molecular hydrogen. Data from the Spitzer spectrograph, which breaks light into its constituent individual wavelengths, indicate the presence of hot steam formed as the outflow heats the surrounding molecular gas. Outflows are physical signatures of processes that create supersonic beams, or jets, of gas. They are usually accompanied by discs of material around the new star, which likely contain the materials from which future planetary systems are formed. Additional newborn stars, depicted in green, can be seen surrounding the DR21 region.

The red filaments stretching across this image denote the presence of polycyclic aromatic hydrocarbons. These organic molecules, comprised of carbon and hydrogen, are excited by surrounding interstellar radiation and become luminescent at wavelengths near 8.0 microns. The complex pattern of filaments is caused by an intricate combination of radiation pressure, gravity and magnetic fields. The result is a tapestry in which winds, outflows and turbulence move and shape the interstellar medium.

To the lower left of the mosaic is a large bubble of gas and dust, which may represent the remnants of a past generation of stars.

Development of megapixel HgCdTe detector arrays with 15 micron cutoff

NASA Astrophysics Data System (ADS)

Forrest, William J.; McMurtry, Craig W.; Dorn, Meghan L.; Pipher, Judith; Cabrera, Mario S.

2016-06-01

I. HistoryHgCdTe is a versatile II-VI semiconductor with a direct-bandgap tunable via the Hg:Cd ratio. Hg:Cd ratio = 53:47 (2.5 micron cutoff) was used on the NICMOS instrument on HST and the 2MASS. Increasing Hg:Cd ratio to 70:30 leads to a 5.4 micron cutoff, utilized in NEOWISE and many JWST instruments. Bailey, Wu et al. (1998) motivated extending this technology to 10 microns and beyond. Bacon, McMurtry et al. (2003, 2004) indicated significant progress toward this longwave (LW) goal.Warm-Spitzer has pioneered passive cooling to below 30 K in space, enabling the JWST mission.II. CurrentNASA's proposed NEOcam mission selected HgCdTe with a 10.6 micron cutoff because it promises natural Zodiacal background limited sensitivity with modest cooling (40 K). Teledyne Imaging Systems (TIS) is producing megapixel arrays with excellent performance (McMurtry, Lee, Dorn et al. (2013)) for this mission.III. FutureModest cooling requirements (circa 30 K) coupled with megapixel arrays and LW sensitivity in the thermal IR make HgCdTe attractive for many infrared instruments. For instance, the spectral signature of a terrestrial planet orbiting in the habitable zone of a nearby star will be the deep and wide absorption by CO_2 centered at 15 microns (Seager and Deming, 2010). LW instruments can enhance Solar System missions, such as exploration of the Enceladus geysers (Spencer, Buratti et al. 2006). Passive cooling will be adequate for these missions. Modern ground-based observatories will benefit from infrared capability out to the N band (7.5-13.6 microns). The required detector temperatures (30-40 K) are easily achievable using commercially available mechanical cryo-coolers (refrigerators).IV. Progress to dateTIS is developing megapixel HgCdTe arrays sensitive out to 15 microns under the direction of the University of Rochester. As a first step, we have produced arrays with a 13 micron cutoff. The initial measurements indicate very promising performance. We will present the measurements of dark current, noise, and quantum efficiency for these devices and discuss our plans to reach our 15 micron target wavelength.

Development of megapixel HgCdTe detector arrays with 15 micron cutoff

NASA Astrophysics Data System (ADS)

Forrest, William J.; McMurtry, Craig W.; Dorn, Meghan; Pipher, Judith; Cabrera, Mario S.

2016-10-01

I. HistoryHgCdTe is a versatile II-VI semiconductor with a direct-bandgap tunable via the Hg:Cd ratio. Hg:Cd ratio = 53:47 (2.5 micron cutoff) was used on the NICMOS instrument on HST and the 2MASS. Increasing Hg:Cd ratio to 70:30 leads to a 5.4 micron cutoff, utilized in NEOWISE and many JWST instruments. Bailey, Wu et al. (1998) motivated extending this technology to 10 microns and beyond. Bacon, McMurtry et al. (2003, 2004) indicated significant progress toward this longwave (LW) goal.Warm-Spitzer has pioneered passive cooling to below 30 K in space, enabling the JWST mission.II. CurrentNASA's proposed NEOcam mission selected HgCdTe with a 10.6 micron cutoff because it promises natural Zodiacal background limited sensitivity with modest cooling (40 K). Teledyne Imaging Systems (TIS) is producing megapixel arrays with excellent performance (McMurtry, Lee, Dorn et al. (2013)) for this mission.III. FutureModest cooling requirements (circa 30 K) coupled with megapixel arrays and LW sensitivity in the thermal IR make HgCdTe attractive for many infrared instruments. For instance, the spectral signature of a terrestrial planet orbiting in the habitable zone of a nearby star will be the deep and wide absorption by CO_2 centered at 15 microns (Seager and Deming, 2010). LW instruments can enhance Solar System missions, such as exploration of the Enceladus geysers (Spencer, Buratti et al. 2006). Passive cooling will be adequate for these missions. Modern ground-based observatories will benefit from infrared capability out to the N band (7.5-13.6 microns). The required detector temperatures (30-40 K) are easily achievable using commercially available mechanical cryo-coolers (refrigerators).IV. Progress to dateTIS is developing megapixel HgCdTe arrays sensitive out to 15 microns under the direction of the University of Rochester. As a first step, we have produced arrays with a 13 micron cutoff. The initial measurements indicate very promising performance. We will present the measurements of dark current, noise, and quantum efficiency for these devices and discuss our plans to reach our 15 micron target wavelength.

VizieR Online Data Catalog: Selecting IRAC counterparts to SMGs (Alberts+, 2013)

NASA Astrophysics Data System (ADS)

Alberts, S.; Wilson, G. W.; Lu, Y.; Johnson, S.; Yun, M. S.; Scott, K. S.; Pope, A.; Aretxaga, I.; Ezawa, H.; Hughes, D. H.; Kawabe, R.; Kim, S.; Kohno, K.; Oshima, T.

2014-05-01

We present a new submm/mm galaxy counterpart identification technique which builds on the use of Spitzer Infrared Array Camera (IRAC) colours as discriminators between likely counterparts and the general IRAC galaxy population. Using 102 radio- and Submillimeter Array-confirmed counterparts to AzTEC sources across three fields [Great Observatories Origins Deep Survey-North, -South and Cosmic Evolution Survey (COSMOS)], we develop a non-parametric IRAC colour-colour characteristic density distribution, which, when combined with positional uncertainty information via likelihood ratios, allows us to rank all potential IRAC counterparts around submillimetre galaxies (SMGs) and calculate the significance of each ranking via the reliability factor. We report all robust and tentative radio counterparts to SMGs, the first such list available for AzTEC/COSMOS, as well as the highest ranked IRAC counterparts for all AzTEC SMGs in these fields as determined by our technique. We demonstrate that the technique is free of radio bias and thus applicable regardless of radio detections. For observations made with a moderate beam size (~18"), this technique identifies ~85% of SMG counterparts. For much larger beam sizes (>~30"), we report identification rates of 33-49%. Using simulations, we demonstrate that this technique is an improvement over using positional information alone for observations with facilities such as AzTEC on the Large Millimeter Telescope and Submillimeter Common User Bolometer Array 2 on the James Clerk Maxwell Telescope. (3 data files).

Galactic Hearts of Glass

NASA Technical Reports Server (NTRS)

2006-01-01

[figure removed for brevity, see original site] Click on image for larger graph

This artist's concept shows delicate greenish crystals sprinkled throughout the violent core of a pair of colliding galaxies. The white spots represent a thriving population of stars of all sizes and ages. NASA's Spitzer Space Telescope detected more than 20 bright and dusty galactic mergers like the one depicted here, all teeming with the tiny gem-like crystals.

When galaxies collide, they trigger the birth of large numbers of massive stars. Astronomers believe these blazing hot stars act like furnaces to produce silicate crystals in the same way that glass is made from sand. The stars probably shed the crystals as they age, and as they blow apart in supernovae explosions.

At the same time the crystals are being churned out, they are also being destroyed. Fast-moving particles from supernova blasts easily convert silicates crystals back to their amorphous, or shapeless, form.

How is Spitzer seeing the crystals if they are rapidly disappearing? Astronomers say that, for a short period of time at the beginning of galactic mergers, massive stars might be producing silicate crystals faster than they are eliminating them. When our own galaxy merges with the Andromeda galaxy in a few billion years, a similar burst of massive stars and silicate crystals might occur.

Crystal Storm in Distant Galaxy The graph (see inset above) of infrared data from NASA's Spitzer Space Telescope tells astronomers that a distant galaxy called IRAS 08752+3915 is experiencing a storm of tiny crystals made up of silicates. The crystals are similar to the glass-like grains of sand found on Earth's many beaches.

The data were taken by Spitzer's infrared spectrograph, which splits light open to reveal its rainbow-like components. The resulting spectrum shown here reveals the signatures of both crystalline (green) and non-crystalline (brown) silicates.

Spitzer detected the same crystals in 20 additional galaxies, all belonging to a class called ultraluminous infrared galaxies. These extremely bright and dusty galaxies usually consist of two galaxies in the process of smashing into each other. Astronomers believe massive stars at the hearts of the galaxies are churning out clouds of silicate crystals. This phenomenon may represent a short-lived phase in the evolution of galactic mergers.

Bow Shocks in Space

NASA Image and Video Library

2016-01-05

Bow shocks thought to mark the paths of massive, speeding stars are highlighted in these images from NASA's Spitzer Space Telescope and Wide-field Infrared Survey Explorer, or WISE. Cosmic bow shocks occur when massive stars zip through space, pushing material ahead of them in the same way that water piles up in front of a race boat. The stars also produce high-speed winds that smack into this compressed material. The end result is pile-up of heated material that glows in infrared light. In these images, infrared light has been assigned the colored red. Green shows wispy dust in the region and blue shows stars. The two images at left are from Spitzer, and the one on the right is from WISE. The speeding stars thought to be creating the bow shocks can be seen at the center of each arc-shaped feature. The image at right actually consists of two bow shocks and two speeding stars. All the speeding stars are massive, ranging from about 8 to 30 times the mass of our sun. http://photojournal.jpl.nasa.gov/catalog/PIA20062

The Spitzer Atlas of Stellar Spectra (SASS)

NASA Astrophysics Data System (ADS)

Ardila, D. R.; van Dyk, S. D., Makowiecki, W.; Stauffer, J.; Song, I.; Ro, J.; Fajardo-Acosta, S.; Hoard, D. W.; Wachter, S.

2011-11-01

We present the Spitzer Atlas of Stellar Spectra (SASS), which includes 159 stellar spectra (5 to 32 micron; R about 100) taken with the Infrared Spectrograph on the Spitzer Space Telescope. This Atlas gathers representative spectra of a broad section of the Hertzsprung-Russell diagram, intended to serve as a general stellar spectral reference in the mid-infrared. It includes stars from all luminosity classes, as well as Wolf-Rayet (WR) objects. Furthermore, it includes some objects of intrinsic interest, like blue stragglers and certain pulsating variables. All the spectra have been uniformly reduced, and all are available online. For dwarfs and giants, the spectra of early-type objects are relatively featureless, dominated by Hydrogen lines around A spectral types. Besides these, the most noticeable photospheric features correspond to water vapor and silicon monoxide in late-type objects and methane and ammonia features at the latest spectral types. Most supergiant spectra in the Atlas present evidence of circumstellar gas. The sample includes five M supergiant spectra, which show strong dust excesses and in some cases PAH features. Sequences of WR stars present the well-known pattern of lines of He I and He II, as well as forbidden lines of ionized metals. The characteristic flat-top shape of the [Ne III] line is evident even at these low spectral resolutions. Several Luminous Blue Variables and other transition stars are present in the Atlas and show very diverse spectra, dominated by circumstellar gas and dust features. We show that the [8]-[24] Spitzer colors (IRAC and MIPS) are poor predictors of spectral type for most luminosity classes.

Tiny Particles, So Far Away

NASA Image and Video Library

2005-01-10

NASA's Spitzer Space Telescope recently captured these images of the star Vega, located 25 light years away in the constellation Lyra. Spitzer was able to detect the heat radiation from the cloud of dust around the star and found that the debris disc is much larger than previously thought. This side by side comparison, taken by Spitzer's multiband imaging photometer, shows the warm infrared glows from dust particles orbiting the star at wavelengths of 24 microns (figure 2 in blue) and 70 microns (figure 3 in red). Both images show a very large, circular and smooth debris disc. The disc radius extends to at least 815 astronomical units. (One astronomical unit is the distance from Earth to the Sun, which is 150-million kilometers or 93-million miles). Scientists compared the surface brightness of the disc in the infrared wavelengths to determine the temperature distribution of the disc and then infer the corresponding particle size in the disc. Most of the particles in the disc are only a few microns in size, or 100 times smaller than a grain of Earth sand. These fine dust particles originate from collisions of embryonic planets near the star at a radius of approximately 90 astronomical units, and are then blown away by Vega's intense radiation. The mass and short lifetime of these small particles indicate that the disc detected by Spitzer is the aftermath of a large and relatively recent collision, involving bodies perhaps as big as the planet Pluto. The images are 3 arcminutes on each side. North is oriented upward and east is to the left. http://photojournal.jpl.nasa.gov/catalog/PIA07218

Ring of Stellar Fire

NASA Image and Video Library

2014-10-22

This image from NASA Spitzer Space Telescope shows where the action is taking place in galaxy NGC 1291. The outer ring, colored red, is filled with new stars that are igniting and heating up dust that glows with infrared light.

Asteroid Bites the Dust Around Dead Star Artist Concept

NASA Image and Video Library

2009-01-05

NASA Spitzer Space Telescope set its infrared eyes upon the dusty remains of shredded asteroids around several dead stars. This artist concept illustrates a white dwarf, surrounded by the bits and pieces of a disintegrating asteroid.

The Pacman Nebula

NASA Image and Video Library

2011-09-28

This composite image of the star cluster NGC 28 contains X-ray data from Chandra, in purple, with infrared observations from Spitzer, in red, green, blue. NGC 281 is known informally as the Pacman Nebula because of its appearance in optical images.

Weighing in on the Dumbbell Nebula

NASA Image and Video Library

2011-08-10

The Dumbbell nebula, also known as Messier 27, pumps out infrared light in this image from NASA Spitzer Space Telescope. Planetary nebulae are now known to be the remains of stars that once looked a lot like our sun.

An Audience Favorite Nebula

NASA Image and Video Library

2012-03-08

This nebula, which is in the constellation of Scutum, has no common name since it is hidden behind dust clouds. It takes an infrared telescope like NASA Spitzer to see through this dark veil and reveal this spectacular hidden nebula.

The Serpent Star-Forming Cloud Spawns Stars

NASA Image and Video Library

2014-05-28

Studied by astronomers, Serpens Cloud Core is one of the youngest collections of stars ever seen in our galaxy. This infrared image combines data from NASA Spitzer with shorter-wavelength observations from the Two Micron All Sky Survey.

Improved characterization of the TRAPPIST-1 planets

NASA Astrophysics Data System (ADS)

Delrez, Laetitia; Triaud, Amaury; Gillon, Michael; Demory, Brice-Olivier; Ingalls, Jim; Carey, Sean; Bolmont, Emeline; Queloz, Didier; Jehin, Emmanuel; de, Julien; Kilpatrick, Brian

2017-07-01

The aim of this DDT is to improve the characterization of the TRAPPIST-1 planets by using Spitzer to gather further high-precision infrared photometric time-series. The AORs for this program are in program ID 13067.

The Universe First Fireworks

NASA Image and Video Library

2006-12-18

This is an image from NASA Spitzer Space Telescope of stars and galaxies in the Ursa Major constellation. This infrared image covers a region of space so large that light would take up to 100 million years to travel across it.

Extrasolar Planets Observed with JWST and the ELTs

NASA Technical Reports Server (NTRS)

Deming, L. Drake

2010-01-01

The advent of cryogenic space-borne infrared observatories such as the Spitzer Space Telescope has lead to a revolution in the study of planets and planetary systems orbiting sun-like stars. Already Spitzer has characterized the emergent infrared spectra of close-in giant exoplanets using transit and eclipse techniques. The James Webb Space Telescope (JWST) will be able to extend these studies to superEarth exoplanets orbiting in the habitable zones of M-dwarf stars in the near solar neighborhood. The forthcoming ground-based Extremely Large Telescopes (ELTs) will playa key role in these studies, being especially valuable for spectroscopy at higher spectral resolving powers where large photon fluxes are needed. The culmination of this work within the next two decades will be the detection and spectral characterization of the major molecular constituents in the atmosphere of a habitable superEarth orbiting a nearby lower main sequence star.

Spitzer Observations of the North Ecliptic Pole

NASA Astrophysics Data System (ADS)

Nayyeri, H.; Ghotbi, N.; Cooray, A.; Bock, J.; Clements, D. L.; Im, M.; Kim, M. G.; Korngut, P.; Lanz, A.; Lee, H. M.; Lee, D. H.; Malkan, M.; Matsuhara, H.; Matsumoto, T.; Matsuura, S.; Nam, U. W.; Pearson, C.; Serjeant, S.; Smidt, J.; Tsumura, K.; Wada, T.; Zemcov, M.

2018-02-01

We present a photometric catalog for Spitzer Space Telescope warm mission observations of the North Ecliptic Pole (NEP; centered at R.A. = 18h00m00s, decl. = 66d33m38.ˢ552). The observations are conducted with IRAC in the 3.6 and 4.5 μm bands over an area of 7.04 deg2, reaching 1σ depths of 1.29 μJy and 0.79 μJy in the 3.6 μm and 4.5 μm bands, respectively. The photometric catalog contains 380,858 sources with 3.6 and 4.5 μm band photometry over the full-depth NEP mosaic. Point-source completeness simulations show that the catalog is 80% complete down to 19.7 AB. The accompanying catalog can be used for constraining the physical properties of extragalactic objects, studying the AGN population, measuring the infrared colors of stellar objects, and studying the extragalactic infrared background light.

Spitzer Spectroscopy of Low-Mass Dwarfs - Clouds and Chemistry at the Bottom of the IMF

NASA Technical Reports Server (NTRS)

Roellig, Thomas L.

2006-01-01

Brown dwarfs and low-mass stars show evidence of complicated atmospheres, including a variety of molecular species and clouds. Infrared observations are one of the best probes of the physics of these objects, but up until recently these observations have been limited in studies from ground-based telescopes by atmospheric absorption and insufficient sensitivity. With the launch of the Spitzer Space Telescope with its Infrared Spectrograph (IRS) instrument we now have the capability to undertake a systematic study of the atmospheric structure and chemistry in these cool objects. The IRS Dim Suns team has compiled spectra from objects ranging from M1 dwarfs with effective temperatures 3,800K of down to T8 dwarfs with effective temperatures of 700. This talk will present these results and discuss their implications for our understanding of cool dwarf atmospheric physics and structure.

Astronomy from Space: The Hubble, Herschel and James Webb Space Telescopes

NASA Technical Reports Server (NTRS)

Gardner, Jonathan P.

2009-01-01

Space-based astronomy is going through a renaissance, with three Great Observatories currently flying: Hubble in the visible and ultraviolet, Spitzer in the infrared and Chandra in X-rays. The future looks equally bright. The final servicing mission to Hubble will take place in February 2009 and promises to make the observatory more capable than ever with two new cameras, and refurbishment that will allow it to last at least five years. The upcoming launch of the Herschel Space Telescope will open the far-infrared to explore the cool and dusty Universe. Finally, we look forward to the launch of the James Webb Space Telescope in 2013, which wil provide a successor to both Hubble and Spitzer. In this talk, the author discusses some of the highlights of scientific discovery in the last 10 years and reveals the promise to the next 10 years.

Rosette globulettes and shells in the infrared

NASA Astrophysics Data System (ADS)

Mäkelä, M. M.; Haikala, L. K.; Gahm, G. F.

2014-07-01

Context. Giant galactic H ii regions surrounding central young clusters show compressed molecular shells, which have broken up into clumps, filaments, and elephant trunks interacting with UV light from central OB stars. Tiny, dense clumps of subsolar mass, called globulettes, form in this environment. Aims: We observe and explore the nature and origin of the infrared emission and extinction in these cool, dusty shell features and globulettes in one H ii region, the Rosette nebula, and search for associated newborn stars. Methods: We imaged the northwestern quadrant of the Rosette nebula in the near-infrared (NIR) through wideband JHKs filters and narrowband H2 1-0 S(1) and Pβ plus continuum filters using the Son of Isaac (SOFI) instrument at the New Technology Telescope (NTT) at European Southern Observatory (ESO). We used the NIR images to study the surface brightness of the globulettes and associated bright rims. We used the NIR JHKs photometry to create a visual extinction map and to search for objects with NIR excess emission. In addition, archival images from Spitzer Infrared Array Camera (IRAC) and Multiband Imaging Photometer for Spitzer (MIPS) 24 μm and Herschel Photoconductor Array Camera and Spectrometer (PACS) observations, covering several bands in the mid-infrared and far-infrared, were used to further analyze the stellar population, to examine the structure of the trunks and other shell structures and to study this Rosette nebula photon-dominated region in more detail. Results: The globulettes and elephant trunks have bright rims in the Ks band, which are unresolved in our images, on the sides facing the central cluster. An analysis of 21 globulettes, where surface brightness in the H2 1-0 S(1) line at 2.12 μm is detected, shows that approximately a third of the surface brightness observed in the Ks filter is due to this line: the observed average of the H2/Ks surface brightness is 0.26 ± 0.02 in the globulettes' cores and 0.30 ± 0.01 in the rims. The estimated H2 1-0 S(1) surface brightness of the rims is ˜3-8 × 10-8 Wm-2 sr-1μm-1. The ratio of the surface brightnesses support fluorescence instead of shocks as the H2 excitation mechanism. The globulettes have number densities of n(H2) ˜ 10-4 cm-3 or higher. We estimated masses of individual globulettes and compared them to the results from previous optical and radio molecular line surveys. We confirm that the larger globulettes contain very dense cores, that the density is also high farther out from the core, and that their mass is subsolar. Two NIR protostellar objects were found in an elephant trunk and one was found in the most massive globulette in our study. Based on observations done at the European Southern Observatory, La Silla, Chile (ESO programmes 084.C-0299 and 088.C-0630).Appendix A is only available in electronic form at http://www.aanda.orgTables 5 and 6 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/567/A108

The Carnegie-Spitzer-IMACS Redshift Survey of Galaxy Evolution since z = 1.5. I. Description and Methodology

NASA Astrophysics Data System (ADS)

Kelson, Daniel D.; Williams, Rik J.; Dressler, Alan; McCarthy, Patrick J.; Shectman, Stephen A.; Mulchaey, John S.; Villanueva, Edward V.; Crane, Jeffrey D.; Quadri, Ryan F.

2014-03-01

We describe the Carnegie-Spitzer-IMACS (CSI) Survey, a wide-field, near-IR selected spectrophotometric redshift survey with the Inamori Magellan Areal Camera and Spectrograph (IMACS) on Magellan-Baade. By defining a flux-limited sample of galaxies in Spitzer Infrared Array Camera 3.6 μm imaging of SWIRE fields, the CSI Survey efficiently traces the stellar mass of average galaxies to z ~ 1.5. This first paper provides an overview of the survey selection, observations, processing of the photometry and spectrophotometry. We also describe the processing of the data: new methods of fitting synthetic templates of spectral energy distributions are used to derive redshifts, stellar masses, emission line luminosities, and coarse information on recent star formation. Our unique methodology for analyzing low-dispersion spectra taken with multilayer prisms in IMACS, combined with panchromatic photometry from the ultraviolet to the IR, has yielded high-quality redshifts for 43,347 galaxies in our first 5.3 deg2 of the SWIRE XMM-LSS field. We use three different approaches to estimate our redshift errors and find robust agreement. Over the full range of 3.6 μm fluxes of our selection, we find typical redshift uncertainties of σ z /(1 + z) <~ 0.015. In comparisons with previously published spectroscopic redshifts we find scatters of σ z /(1 + z) = 0.011 for galaxies at 0.7 <= z <= 0.9, and σ z /(1 + z) = 0.014 for galaxies at 0.9 <= z <= 1.2. For galaxies brighter and fainter than i = 23 mag, we find σ z /(1 + z) = 0.008 and σ z /(1 + z) = 0.022, respectively. Notably, our low-dispersion spectroscopy and analysis yields comparable redshift uncertainties and success rates for both red and blue galaxies, largely eliminating color-based systematics that can seriously bias observed dependencies of galaxy evolution on environment. This paper includes data gathered with the 6.5 m Magellan Telescopes located at Las Campanas Observatory, Chile.

THE SPITZER-IRAC POINT-SOURCE CATALOG OF THE VELA-D CLOUD

DOE Office of Scientific and Technical Information (OSTI.GOV)

Strafella, F.; Elia, D.; Campeggio, L., E-mail: francesco.strafella@le.infn.i, E-mail: loretta.campeggio@le.infn.i, E-mail: eliad@oal.ul.p

2010-08-10

This paper presents the observations of Cloud D in the Vela Molecular Ridge, obtained with the Infrared Array Camera (IRAC) camera on board the Spitzer Space Telescope at the wavelengths {lambda} = 3.6, 4.5, 5.8, and 8.0 {mu}m. A photometric catalog of point sources, covering a field of approximately 1.2 deg{sup 2}, has been extracted and complemented with additional available observational data in the millimeter region. Previous observations of the same region, obtained with the Spitzer MIPS camera in the photometric bands at 24 {mu}m and 70 {mu}m, have also been reconsidered to allow an estimate of the spectral slopemore » of the sources in a wider spectral range. A total of 170,299 point sources, detected at the 5{sigma} sensitivity level in at least one of the IRAC bands, have been reported in the catalog. There were 8796 sources for which good quality photometry was obtained in all four IRAC bands. For this sample, a preliminary characterization of the young stellar population based on the determination of spectral slope is discussed; combining this with diagnostics in the color-magnitude and color-color diagrams, the relative population of young stellar objects (YSOs) in different evolutionary classes has been estimated and a total of 637 candidate YSOs have been selected. The main differences in their relative abundances have been highlighted and a brief account for their spatial distribution is given. The star formation rate has also been estimated and compared with the values derived for other star-forming regions. Finally, an analysis of the spatial distribution of the sources by means of the two-point correlation function shows that the younger population, constituted by the Class I and flat-spectrum sources, is significantly more clustered than the Class II and III sources.« less

Studying Galaxy Formation with the Hubble, Spitzer and James Webb Space Telescopes

NASA Technical Reports Server (NTRS)

Gardner, Jonathan P.

2009-01-01

The deepest optical to infrared observations of the universe include the Hubble Deep Fields, the Great Observatories Origins Deep Survey and the recent Hubble Ultra-Deep Field. Galaxies are seen in these surveys at redshifts z greater than 6, less than 1 Gyr after the Big Bang, at the end of a period when light from the galaxies has reionized Hydrogen in the inter-galactic medium. These observations, combined with theoretical understanding, indicate that the first stars and galaxies formed at z greater than 10, beyond the reach of the Hubble and Spitzer Space Telescopes. To observe the first galaxies, NASA is planning the James Webb Space Telescope (JWST), a large (6.5m), cold (less than 50K), infrared-optimized observatory to be launched early in the next decade into orbit around the second Earth-Sun Lagrange point. JWST will have four instruments: The Near-Infrared Camera, the Near-Infrared multi-object Spectrograph, and the Tunable Filter Imager will cover the wavelength range 0.6 to 5 microns, while the Mid-Infrared Instrument will do both imaging and spectroscopy from 5 to 28.5 microns. In addition to JWST's ability to study the formation and evolution of galaxies, I will also briefly review its expected contributions to studies of the formation of stars and planetary systems, and discuss recent progress in constructing the observatory.

The First Detection of [O IV] from an Ultraluminous X-ray Source with Spitzer. I. Observational Results for Holmberg II ULX

NASA Technical Reports Server (NTRS)

Berghea, C. T.; Dudik, R. P.; Weaver, K. A.; Kallman, T. R.

2009-01-01

We presen the first Spitzer Infrared Spectrograph (IRS) observations of the [O IV] 25.89 um emission line detected from the ultraluminous X-ray source (ULX) in Holmberg II. This line is a well established signature of high excitation usually associated with AGN. Its detection suggests that the ULX has a strong impact on the surrounding gas. A Spitzer high resolution spectral map shows that the [O IV] is coincident with the X-ray position of the ULX. The ratios of the [O IV] to lower ionization lines are similar to those observed in AGN, suggesting that a strong UV and X-ray source is responsible for the, photoionization. The best XMM-Newton data is used to model the X-ray band which is then extrapolated into the UV. We perform infrared and ultraviolet photometry, and use its previously published optical and radio data to construct the full SED for the ULX and its companion. The preferred model to describe the SED includes an accretion disk which dominates the soft X-rays but contributes little at UV and optical wavelengths. The optical counterpart is consistent with a B supergiant as previously suggested in other studies. The bolometric luminosity of the ULX suggests the presence of an intermediate-mass black hole with mass >85 M for sub-Eddington accretion or, alternatively, a stellar-mass black hole that is accreting at super-Eddington rates. In a follow-up second paper we perform detailed photoionization modeling of the infrared lines in order to constrain the bolometric luminosity of the ULX.

Spitzer Infrared Spectrograph Observations of the Galactic Center: Quantifying the Extreme Ultraviolet/Soft X-ray Fluxes

NASA Astrophysics Data System (ADS)

Simpson, Janet P.

2018-04-01

It has long been shown that the extreme ultraviolet spectrum of the ionizing stars of H II regions can be estimated by comparing the observed line emission to detailed models. In the Galactic Center (GC), however, previous observations have shown that the ionizing spectral energy distribution (SED) of the local photon field is strange, producing both very low excitation ionized gas (indicative of ionization by late O stars) and also widespread diffuse emission from atoms too highly ionized to be found in normal H II regions. This paper describes the analysis of all GC spectra taken by Spitzer's Infrared Spectrograph and downloaded from the Spitzer Heritage Archive. In it, H II region densities and abundances are described, and serendipitously discovered candidate planetary nebulae, compact shocks, and candidate young stellar objects are tabulated. Models were computed with Cloudy, using SEDs from Starburst99 plus additional X-rays, and compared to the observed mid-infrared forbidden and recombination lines. The ages inferred from the model fits do not agree with recent proposed star formation sequences (star formation in the GC occurring along streams of gas with density enhancements caused by close encounters with the black hole, Sgr A*), with Sgr B1, Sgr C, and the Arches Cluster being all about the same age, around 4.5 Myr old, with similar X-ray requirements. The fits for the Quintuplet Cluster appear to give a younger age, but that could be caused by higher-energy photons from shocks from stellar winds or from a supernova.

WARM SPITZER OBSERVATIONS OF THREE HOT EXOPLANETS: XO-4b, HAT-P-6b, AND HAT-P-8b

DOE Office of Scientific and Technical Information (OSTI.GOV)

Todorov, Kamen O.; Deming, Drake; Knutson, Heather A.

2012-02-10

We analyze Warm Spitzer/Infrared Array Camera observations of the secondary eclipses of three planets, XO-4b, HAT-P-6b, and HAT-P-8b. We measure secondary eclipse amplitudes at 3.6 {mu}m and 4.5 {mu}m for each target. XO-4b exhibits a stronger eclipse depth at 4.5 {mu}m than at 3.6 {mu}m, which is consistent with the presence of a temperature inversion. HAT-P-8b shows a stronger eclipse amplitude at 3.6 {mu}m and is best described by models without a temperature inversion. The eclipse depths of HAT-P-6b can be fitted with models with a small or no temperature inversion. We consider our results in the context of amore » postulated relationship between stellar activity and temperature inversion and a relationship between irradiation level and planet dayside temperature, as discussed by Knutson et al. and Cowan and Agol, respectively. Our results are consistent with these hypotheses, but do not significantly strengthen them. To measure accurate secondary eclipse central phases, we require accurate ephemerides. We obtain primary transit observations and supplement them with publicly available observations to update the orbital ephemerides of the three planets. Based on the secondary eclipse timing, we set upper boundaries for ecos ({omega}) for HAT-P-6b, HAT-P-8b, and XO-4b and find that the values are consistent with circular orbits.« less

Galaxy Cluster IDCS J1426

NASA Image and Video Library

2016-01-07

Astronomers have made the most detailed study yet of an extremely massive young galaxy cluster using three of NASA's Great Observatories. This multi-wavelength image shows this galaxy cluster, called IDCS J1426.5+3508 (IDCS 1426 for short), in X-rays recorded by the Chandra X-ray Observatory in blue, visible light observed by the Hubble Space Telescope in green, and infrared light detected by the Spitzer Space Telescope in red. This rare galaxy cluster, which is located 10 billion light-years from Earth, is almost as massive as 500 trillion suns. This object has important implications for understanding how such megastructures formed and evolved early in the universe. The light astronomers observed from IDCS 1426 began its journey to Earth when the universe was less than a third of its current age. It is the most massive galaxy cluster detected at such an early time. First discovered by the Spitzer Space Telescope in 2012, IDCS 1426 was then observed using the Hubble Space Telescope and the Keck Observatory to determine its distance. Observations from the Combined Array for Millimeter-wave Astronomy indicated it was extremely massive. New data from the Chandra X-ray Observatory confirm the galaxy cluster's mass and show that about 90 percent of this mass is in the form of dark matter -- the mysterious substance that has so far been detected only through its gravitational pull on normal matter composed of atoms. http://photojournal.jpl.nasa.gov/catalog/PIA20063

The Invisible Dragon

NASA Image and Video Library

2010-07-07

A dragon-shaped cloud of dust seems to fly out from a bright explosion in this infrared light image from NASA Spitzer Space Telescope. These views have revealed that this dark cloud, called M17 SWex, is forming stars at a furious rate.

Stars Spring up Out of the Darkness Artist Concept

NASA Image and Video Library

2006-12-18

This artist animation illustrates the universe early years, from its explosive formation to its dark ages to its first stars and mini-galaxies. Scientists using NASA Spitzer Space Telescope found patches of infrared light splattered across the sky.

Charting Ingredients for Life

NASA Image and Video Library

2005-07-27

This graph, or spectrum, from NASA Spitzer Space Telescope, charts light from a faraway galaxy located 10 billion light years from Earth. It tracks mid-infrared light from an extremely luminous galaxy when the universe was only 1/4 of its current age.

North America Nebula in Different Lights

NASA Image and Video Library

2011-02-10

This view of the North America nebula combines both visible and infrared light observations, taken by the Digitized Sky Survey and NASA Spitzer Space Telescope. Clusters of young stars about one million years old can be found throughout the image.

Pointing History Engine for the Spitzer Space Telescope

NASA Technical Reports Server (NTRS)

Bayard, David; Ahmed, Asif; Brugarolas, Paul

2007-01-01

The Pointing History Engine (PHE) is a computer program that provides mathematical transformations needed to reconstruct, from downlinked telemetry data, the attitude of the Spitzer Space Telescope (formerly known as the Space Infrared Telescope Facility) as a function of time. The PHE also serves as an example for development of similar pointing reconstruction software for future space telescopes. The transformations implemented in the PHE take account of the unique geometry of the Spitzer telescope-pointing chain, including all data on relative alignments of components, and all information available from attitude-determination instruments. The PHE makes it possible to coordinate attitude data with observational data acquired at the same time, so that any observed astronomical object can be located for future reference and re-observation. The PHE is implemented as a subroutine used in conjunction with telemetry-formatting services of the Mission Image Processing Laboratory of NASA s Jet Propulsion Laboratory to generate the Boresight Pointing History File (BPHF). The BPHF is an archival database designed to serve as Spitzer s primary astronomical reference documenting where the telescope was pointed at any time during its mission.

Advanced Optimal Extraction for the Spitzer/IRS

NASA Astrophysics Data System (ADS)

Lebouteiller, V.; Bernard-Salas, J.; Sloan, G. C.; Barry, D. J.

2010-02-01

We present new advances in the spectral extraction of pointlike sources adapted to the Infrared Spectrograph (IRS) on board the Spitzer Space Telescope. For the first time, we created a supersampled point-spread function of the low-resolution modules. We describe how to use the point-spread function to perform optimal extraction of a single source and of multiple sources within the slit. We also examine the case of the optimal extraction of one or several sources with a complex background. The new algorithms are gathered in a plug-in called AdOpt which is part of the SMART data analysis software.

DUST AROUND R CORONAE BOREALIS STARS. II. INFRARED EMISSION FEATURES IN AN H-POOR ENVIRONMENT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Garcia-Hernandez, D. A.; Rao, N. Kameswara; Lambert, D. L., E-mail: agarcia@iac.es, E-mail: nkrao@iiap.res.in, E-mail: dll@astro.as.utexas.edu

2013-08-20

Residual Spitzer/Infrared Spectrograph spectra for a sample of 31 R Coronae Borealis (RCB) stars are presented and discussed in terms of narrow emission features superimposed on the quasi-blackbody continuous infrared emission. A broad {approx}6-10 {mu}m dust emission complex is seen in the RCBs showing an extreme H-deficiency. A secondary and much weaker {approx}11.5-15 {mu}m broad emission feature is detected in a few RCBs with the strongest {approx}6-10 {mu}m dust complex. The Spitzer infrared spectra reveal for the first time the structure within the {approx}6-10 {mu}m dust complex, showing the presence of strong C-C stretching modes at {approx}6.3 and 8.1 {mu}mmore » as well as of other dust features at {approx}5.9, 6.9, and 7.3 {mu}m, which are attributable to amorphous carbonaceous solids with little or no hydrogen. The few RCBs with only moderate H-deficiencies display the classical ''unidentified infrared bands (UIRs)'' and mid-infrared features from fullerene-related molecules. In general, the characteristics of the RCB infrared emission features are not correlated with the stellar and circumstellar properties, suggesting that the RCB dust features may not be dependent on the present physical conditions around RCB stars. The only exception seems to be the central wavelength of the 6.3 {mu}m feature, which is blueshifted in those RCBs showing also the UIRs, i.e., the RCBs with the smallest H deficiency.« less

THE YOUNG STELLAR POPULATION OF LYNDS 1340. AN INFRARED VIEW

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kun, M.; Moór, A.; Wolf-Chase, G.

We present results of an infrared study of the molecular cloud Lynds 1340, forming three groups of low- and intermediate-mass stars. Our goals are to identify and characterize the young stellar population of the cloud, study the relationships between the properties of the cloud and the emergent stellar groups, and integrate L1340 into the picture of the star-forming activity of our Galactic environment. We selected candidate young stellar objects (YSOs) from the Spitzer and WISE databases using various published color criteria and classified them based on the slope of the spectral energy distribution (SED). We identified 170 Class II, 27more » flat SED, and 45 Class 0/I sources. High angular resolution near-infrared observations of the RNO 7 cluster, embedded in L1340, revealed eight new young stars of near-infrared excess. The surface density distribution of YSOs shows three groups, associated with the three major molecular clumps of L1340, each consisting of ≲100 members, including both pre-main-sequence stars and embedded protostars. New Herbig–Haro objects were identified in the Spitzer images. Our results demonstrate that L1340 is a prolific star-forming region of our Galactic environment in which several specific properties of the intermediate-mass mode of star formation can be studied in detail.« less

LUMINOUS AND HIGH STELLAR MASS CANDIDATE GALAXIES AT z Almost-Equal-To 8 DISCOVERED IN THE COSMIC ASSEMBLY NEAR-INFRARED DEEP EXTRAGALACTIC LEGACY SURVEY

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yan Haojing; Finkelstein, Steven L.; Huang, Kuang-Han

One key goal of the Hubble Space Telescope Cosmic Assembly Near-Infrared Deep Extragalactic Legacy Survey is to track galaxy evolution back to z Almost-Equal-To 8. Its two-tiered ''wide and deep'' strategy bridges significant gaps in existing near-infrared surveys. Here we report on z Almost-Equal-To 8 galaxy candidates selected as F105W-band dropouts in one of its deep fields, which covers 50.1 arcmin{sup 2} to 4 ks depth in each of three near-infrared bands in the Great Observatories Origins Deep Survey southern field. Two of our candidates have J < 26.2 mag, and are >1 mag brighter than any previously known F105W-dropouts.more » We derive constraints on the bright end of the rest-frame ultraviolet luminosity function of galaxies at z Almost-Equal-To 8, and show that the number density of such very bright objects is higher than expected from the previous Schechter luminosity function estimates at this redshift. Another two candidates are securely detected in Spitzer Infrared Array Camera images, which are the first such individual detections at z Almost-Equal-To 8. Their derived stellar masses are on the order of a few Multiplication-Sign 10{sup 9} M{sub Sun }, from which we obtain the first measurement of the high-mass end of the galaxy stellar mass function at z Almost-Equal-To 8. The high number density of very luminous and very massive galaxies at z Almost-Equal-To 8, if real, could imply a large stellar-to-halo mass ratio and an efficient conversion of baryons to stars at such an early time.« less

Spitzer Space Telescope Research Program for Teachers and Students

NASA Astrophysics Data System (ADS)

Daou, D.

2005-12-01

The Spitzer Science Center (SSC) and the National Optical Astronomy Observatory (NOAO) have designed a program for teacher and student research using observing time on the Spitzer Space Telescope. The participating teachers attended a fall, 2004 workshop to become familiar with the Spitzer Space Telescope (SST) archives, and to receive training in infrared astronomy and observational techniques. The teachers also attended a workshop offered by the SSC to learn about the observation planning process, and telescope and instrument capabilities. This program has as its goals the fundamental NASA goals of inspiring and motivating students to pursue careers in science, technology, engineering, and mathematics as well as to engage the public in shaping and sharing the experience of exploration and discovery. Our educational plan addresses the NASA objectives of improving student proficiency in science and improving science instruction by providing a unique opportunity to a group of teachers and students to observe with the Spitzer Space Telescope and work on their data with SSC and NOAO scientists. This program allows a team of 12 teachers and their students to utilize up to 3.5 hours of Director's discretionary observing time on the Spitzer Space Telescope for educational observations. Leveraging on a well-established teacher professional development, the SSC is offering this program to teachers in the Teacher Leaders in Research Based Science Education (TLRRBSE), an ongoing program at the NOAO. This NSF-sponsored program touches the formal education community through a national audience of well-trained and supported middle and high school teachers.

A SWIRE Picture is Worth Billions of Years

NASA Technical Reports Server (NTRS)

2005-01-01

[figure removed for brevity, see original site] Figure 1: SWIRE View of Distant Galaxies [figure removed for brevity, see original site] [figure removed for brevity, see original site] [figure removed for brevity, see original site] Figure 2Figure 3 Figure 4

These spectacular images, taken by the Spitzer Wide-area Infrared Extragalactic (SWIRE) Legacy project, encapsulate one of the primary objectives of the Spitzer mission: to connect the evolution of galaxies from the distant, or early, universe to the nearby, or present day, universe.

The Tadpole galaxy (main image) is the result of a recent galactic interaction in the local universe. Although these galactic mergers are rare in the universe's recent history, astronomers believe that they were much more common in the early universe. Thus, SWIRE team members will use this detailed image of the Tadpole galaxy to help understand the nature of the 'faint red-orange specks' of the early universe.

The larger picture (figure 2) depicts one-sixteenth of the SWIRE survey field called ELAIS-N1. In this image, the bright blue sources are hot stars in our own Milky Way, which range anywhere from 3 to 60 times the mass of our Sun. The fainter green spots are cooler stars and galaxies beyond the Milky Way whose light is dominated by older stellar populations. The red dots are dusty galaxies that are undergoing intense star formation. The faintest specks of red-orange are galaxies billions of light-years away in the distant universe.

Figure 3 features an unusual ring-like galaxy called CGCG 275-022. The red spiral arms indicate that this galaxy is very dusty and perhaps undergoing intense star formation. The star-forming activity could have been initiated by a near head-on collision with another galaxy.

The most distant galaxies that SWIRE is able to detect are revealed in a zoom of deep space (figure 4). The colors in this feature represent the same objects as those in the larger field image of ELAIS-N1.

The observed SWIRE fields were chosen on the basis of being 'empty' or as free as possible from the obscuring dust, gas, and stars of our own Milky Way. Because Earth is located within the Milky Way galaxy, there is always a screen of Milky Way objects blocking our view of the rest of the universe. In some places, our view of the larger universe is less obscured than others and for the most part is considered 'empty.' These are prime observing spots for astronomers interested in studying objects beyond the Milky Way. ELAIS-N1 is only one of six SWIRE survey fields. The full survey covers 49 square degrees of the sky, equivalent to the area covered by about 250 full moons.

The SWIRE images are 3-channel false-color composites, where blue represents visible green light (light that would appear to be blue/green to the human eye), green captures infrared light of 3.6 microns, and red represents infrared emissions of 8 microns. The infrared data are from Spitzer's infrared array camera and the visible-light data are from the Isaac Newton Telescope, Spain.

Galactic Gathering Gives Impressive Light Display

NASA Image and Video Library

2014-12-11

This composite image of NGC 2207 and IC 2163 contains Chandra data in pink, optical-light data from NASA Hubble Space Telescope in red, green, and blue appearing as blue, white, orange, and brown, and infrared data from Spitzer Space Telescope in red.

Dissecting Dust from Detonation of Dead Star

NASA Image and Video Library

2014-06-04

This infrared image from NASA Spitzer Space Telescope shows N103B -- all that remains from a supernova that exploded a millennium ago in the Large Magellanic Cloud, a satellite galaxy 160,000 light-years away from our own Milky Way.

A Glimpse of the Milky Way

NASA Image and Video Library

2005-12-13

In visible light, the bulk of our Milky Way galaxy stars are eclipsed behind thick clouds of galactic dust and gas. But to the infrared eyes of NASA Spitzer Space Telescope, distant stars and dust clouds shine with unparalleled clarity and color.

Hunt for infrared photons from the first binary neutron star merger

NASA Astrophysics Data System (ADS)

Kasliwal, Mansi; Growth Collaboration [Global Relay Of Observatories Watching Transients

2017-10-01

Yesterday, within two seconds of 2017 August 17 12:41:04 GMT, both LIGO interferometers and the Fermi satellite detected gravitational waves from a neutron star merger and a short contemporaneous gamma ray burst! We now have a promising optical and infrared counterpart. This may very well be a historic moment in multi-messenger astronomy, and may even prove to be of the same league as neutrinos from SN,1987A. Here, we request the Spitzer Space Telescope to engage in the hunt for infrared photons.

THE SPITZER ATLAS OF STELLAR SPECTRA (SASS)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ardila, David R.; Van Dyk, Schuyler D.; Makowiecki, Wojciech

2010-12-15

We present the Spitzer Atlas of Stellar Spectra, which includes 159 stellar spectra (5-32 {mu}m; R {approx} 100) taken with the Infrared Spectrograph on the Spitzer Space Telescope. This Atlas gathers representative spectra of a broad section of the Hertzsprung-Russell diagram, intended to serve as a general stellar spectral reference in the mid-infrared. It includes stars from all luminosity classes, as well as Wolf-Rayet (WR) objects. Furthermore, it includes some objects of intrinsic interest, such as blue stragglers and certain pulsating variables. All of the spectra have been uniformly reduced, and all are available online. For dwarfs and giants, themore » spectra of early-type objects are relatively featureless, characterized by the presence of hydrogen lines in A spectral types. Besides these, the most noticeable photospheric features correspond to water vapor and silicon monoxide in late-type objects and methane and ammonia features at the latest spectral types. Most supergiant spectra in the Atlas present evidence of circumstellar gas and/or dust. The sample includes five M supergiant spectra, which show strong dust excesses and in some cases polycyclic aromatic hydrocarbon features. Sequences of WR stars present the well-known pattern of lines of He I and He II, as well as forbidden lines of ionized metals. The characteristic flat-top shape of the [Ne III] line is evident even at these low spectral resolutions. Several Luminous Blue Variables and other transition stars are present in the Atlas and show very diverse spectra, dominated by circumstellar gas and dust features. We show that the [8]-[24] Spitzer colors (IRAC and MIPS) are poor predictors of spectral type for most luminosity classes.« less

The Spitzer Atlas of Stellar Spectra (SASS)

NASA Astrophysics Data System (ADS)

Ardila, David R.; Van Dyk, Schuyler D.; Makowiecki, Wojciech; Stauffer, John; Song, Inseok; Rho, Jeonghee; Fajardo-Acosta, Sergio; Hoard, D. W.; Wachter, Stefanie

2010-12-01

We present the Spitzer Atlas of Stellar Spectra, which includes 159 stellar spectra (5-32 μm R ~ 100) taken with the Infrared Spectrograph on the Spitzer Space Telescope. This Atlas gathers representative spectra of a broad section of the Hertzsprung-Russell diagram, intended to serve as a general stellar spectral reference in the mid-infrared. It includes stars from all luminosity classes, as well as Wolf-Rayet (WR) objects. Furthermore, it includes some objects of intrinsic interest, such as blue stragglers and certain pulsating variables. All of the spectra have been uniformly reduced, and all are available online. For dwarfs and giants, the spectra of early-type objects are relatively featureless, characterized by the presence of hydrogen lines in A spectral types. Besides these, the most noticeable photospheric features correspond to water vapor and silicon monoxide in late-type objects and methane and ammonia features at the latest spectral types. Most supergiant spectra in the Atlas present evidence of circumstellar gas and/or dust. The sample includes five M supergiant spectra, which show strong dust excesses and in some cases polycyclic aromatic hydrocarbon features. Sequences of WR stars present the well-known pattern of lines of He I and He II, as well as forbidden lines of ionized metals. The characteristic flat-top shape of the [Ne III] line is evident even at these low spectral resolutions. Several Luminous Blue Variables and other transition stars are present in the Atlas and show very diverse spectra, dominated by circumstellar gas and dust features. We show that the [8]-[24] Spitzer colors (IRAC and MIPS) are poor predictors of spectral type for most luminosity classes.

NASA Galaxy Mission Celebrates Sixth Anniversary

NASA Image and Video Library

2009-04-28

NASA Galaxy Evolution Explorer Mission celebrates its sixth anniversary studying galaxies beyond our Milky Way through its sensitive ultraviolet telescope, the only such far-ultraviolet detector in space. The mission studies the shape, brightness, size and distance of distant galaxies across 10 billion years of cosmic history, giving scientists a wealth of data to help us better understand the origins of the universe. One such object is pictured here, the galaxy NGC598, more commonly known as M33. This image is a blend of the Galaxy Evolution Explorer's M33 image and another taken by NASA's Spitzer Space Telescope. M33, one of our closest galactic neighbors, is about 2.9 million light-years away in the constellation Triangulum, part of what's known as our Local Group of galaxies. Together, the Galaxy Evolution Explorer and Spitzer can see a broad spectrum of sky. Spitzer, for example, can detect mid-infrared radiation from dust that has absorbed young stars' ultraviolet light. That's something the Galaxy Evolution Explorer cannot see. This combined image shows in amazing detail the beautiful and complicated interlacing of the heated dust and young stars. In some regions of M33, dust gathers where there is very little far-ultraviolet light, suggesting that the young stars are obscured or that stars further away are heating the dust. In some of the outer regions of the galaxy, just the opposite is true: There are plenty of young stars and very little dust. Far-ultraviolet light from young stars glimmers blue, near-ultraviolet light from intermediate age stars glows green, near-infrared light from old stars burns yellow and orange, and dust rich in organic molecules burns red. The small blue flecks outside the spiral disk of M33 are most likely distant background galaxies. This image is a four-band composite that, in addition to the two ultraviolet bands, includes near infrared as yellow/orange and far infrared as red. http://photojournal.jpl.nasa.gov/catalog/PIA11999

Models for Temperature and Composition in Uranus from Spitzer, Herschel and Ground-Based Infrared through Millimeter Observations

NASA Astrophysics Data System (ADS)

Orton, Glenn S.; Fletcher, Leigh N.; Feuchtgruber, Helmut; Lellouch, Emmanuel; Moreno, Raphel; Encrenaz, Therese; Hartogh, Paul; Jarchow, Christopher; Swinyard, Bruce; Cavalie, Thibault; Moses, Julianne; Burgdorf, Martin; Hammel, Heidi; Line, Michael; Mainzer, Amy K.; Hofstadter, Mark; Sandell, Goran H.; Dowell, C. Darren; Pantin, Eric; Fujiyoshi, Takuya

2014-11-01

Photometric and spectroscopic observations of Uranus in the thermal infrared were combined to create self-consistent models of its global-mean temperature profile and vertical distribution of gases. These were derived from a suite of observations from Spitzer and Herschel, together with ground-based observations from UKIRT, CSO, Gemini, VLT and Subaru. Observations of the collision-induced absorption and quadrupoles of H2 have constrained the temperature structure for pressures of nearly 2 bars down to 0.1 millibars. We coupled the vertical distribution of CH4 in the stratosphere of Uranus with models for the vertical mixing in such a way to be consistent with the mixing ratios of hydrocarbons. Spitzer and Herschel data constrain the abundances of CH3, CH4, C2H2, C2H6, C3H4, C4H2, H2O and CO2. The Spitzer IRS data, in concert with photochemical models, show that the homopause is at much higher atmospheric pressures than for the other outer planets, with the predominant trace constituents for pressures lower than 30 µbar being H2O and CO2. The ratio of the oxygen-bearing molecules is consistent with exogenic origins in KBOs or comets. At millimeter wavelengths, there is evidence that an additional opacity source is required besides the H2 collision-induced absorption and the NH3 absorption needed to match the microwave spectrum; this can reasonably (but not uniquely) be attributed to H2S. This model is of ‘programmatic’ interest because it serves as a standard calibration source; the cross-comparison of its spectrum with model spectra for Mars and Neptune shows consistency to within 3%. Near equinox, the IRS spectra at different longitudes showed rotationally variable stratospheric emission that is consistent with a temperature anomaly ≤10 K near ~0.1-0.2 mbar. Spatial variability of tropospheric temperatures observed in ground-based observations from 2006 to 2011 is generally consistent with Voyager infrared (IRIS) results.

NASA Space Telescopes See Weather Patterns in Brown Dwarf

NASA Image and Video Library

2017-12-08

JANUARY 8, 2013: Astronomers using NASA's Hubble and Spitzer space telescopes have probed the stormy atmosphere of a brown dwarf named 2MASSJ22282889-431026, creating the most detailed "weather map" yet for this class of cool, star-like orbs. The forecast shows wind-driven, planet-sized clouds enshrouding these strange worlds. Brown dwarfs form out of condensing gas, as stars do, but lack the mass to fuse atoms and produce energy. Instead, these objects, which some call failed stars, are more similar to gas planets with their complex, varied atmospheres. The new research is a stepping stone toward a better understanding not only brown dwarfs, but also of the atmospheres of planets beyond our solar system. Hubble and Spitzer simultaneously watched the brown dwarf as its light varied in time, brightening and dimming about every 90 minutes as the body rotated. Astronomers found the timing of this change in brightness depended on whether they looked using different wavelengths of infrared light. The variations are the result of different layers or patches of material swirling around in the brown dwarf in windy storms as large as Earth itself. Spitzer and Hubble see different atmospheric layers because certain infrared wavelengths are blocked by vapors of water and methane high up, while other infrared wavelengths emerge from much deeper layers. Daniel Apai, the principal investigator of the research from the University of Arizona, Tucson, presented the results at the American Astronomical Society meeting on January 8 in Long Beach, Calif. A study describing the results, led by Esther Buenzli, also of the University of Arizona, is published in the Astrophysical Journal Letters. For more information about this study, visit www.nasa.gov/spitzer . NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

First Map of Alien World animation

NASA Image and Video Library

2007-05-09

This image shows the first-ever map of the surface of an exoplanet, or a planet beyond our solar system. Showing temperature variations across the cloudy tops of a gas giant called HD 189733b, the infrared data is taken by NASA Spitzer Space Telescope.

NASA's Fermi Proves Supernova Remnants Produce Cosmic Rays

NASA Image and Video Library

2017-12-08

The W44 supernova remnant is nestled within and interacting with the molecular cloud that formed its parent star. Fermi's LAT detects GeV gamma rays (magenta) produced when the gas is bombarded by cosmic rays, primarily protons. Radio observations (yellow) from the Karl G. Jansky Very Large Array near Socorro, N.M., and infrared (red) data from NASA's Spitzer Space Telescope reveal filamentary structures in the remnant's shell. Blue shows X-ray emission mapped by the Germany-led ROSAT mission. To read more go to: 1.usa.gov/14V14qi NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram Credit: NASA/DOE/Fermi LAT Collaboration, NRAO/AUI, JPL-Caltech, ROSAT

WISEP J060738.65+242953.4: A NEARBY POLE-ON L8 BROWN DWARF WITH RADIO EMISSION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gizis, John E.; Paudel, Rishi; Williams, Peter K. G.

2016-11-01

We present a simultaneous, multi-wavelength campaign targeting the nearby (7.2 pc) L8/L9 (optical/near-infrared) dwarf WISEP J060738.65+242953.4 in the mid-infrared, radio, and optical. Spitzer Space Telescope observations show no variability at the 0.2% level over 10 hr each in the 3.6 and 4.5 μ m bands. Kepler K2 monitoring over 36 days in Campaign 0 rules out stable periodic signals in the optical with amplitudes greater than 1.5% and periods between 1.5 hr and 2 days. Non-simultaneous Gemini optical spectroscopy detects lithium, constraining this L dwarf to be less than ∼2 Gyr old, but no Balmer emission is observed. The lowmore » measured projected rotation velocity ( v sin i < 6 km s{sup −1}) and lack of variability are very unusual compared to other brown dwarfs, and we argue that this substellar object is likely viewed pole-on. We detect quiescent (non-bursting) radio emission with the Very Large Array. Among radio-detected L and T dwarfs, it has the lowest observed L{sub ν} and the lowest v  sin  i . We discuss the implications of a pole-on detection for various proposed radio emission scenarios.« less

A Panchromatic View of Star-Forming Regions in the Magellanic Clouds: Characterizing Physical and Evolutionary Parameters of 1,000 Young Stellar Objects

NASA Astrophysics Data System (ADS)

Carlson, Lynn R.

2010-01-01

I discuss newly discovered Young Stellar Objects (YSOs) in several star-forming regions in the Magellanic Clouds. I exploit the synergy between infrared photometry from the Spitzer SAGE (Surveying the Agents of Galaxy Evolution) legacy programs, near-infrared and optical photometry from ground-based surveys, and HST imaging to characterize young stellar populations. This reveals a variety of Main Sequence Stars and Proto-Stars over a wide range of evolutionary stages. Through SED fitting, I characterize the youngest, embedded, infrared-bright YSOs. Complementary color-Magnitude analysis and isochrone fitting of optical data allows a statistical description of more evolved, unembedded stellar and protostellar populations within these same regions. I examine the early evolution of Magellanic star clusters, including propagating and triggered star formation, and take a step toward characterizing evolutionary timescales for YSOs. In this talk, I present an overview of the project and exemplify the analysis by focusing on NGC 602 in the SMC and Henize 206 in the LMC as examples. The SAGE Project is supported by NASA/Spitzer grant 1275598 and NASA NAG5-12595.

Mass Loss from Dusty AGB and Red Supergiant Stars in the Magellanic Clouds and in the Galaxy

NASA Astrophysics Data System (ADS)

Sargent, Benjamin A.; Srinivasan, Sundar; Meixner, Margaret; Kastner, Joel

2016-01-01

Asymptotic giant branch (AGB) and red supergiant (RSG) stars are evolved stars that eject large parts of their mass in outflows of dust and gas. As part of an ongoing effort to measure mass loss from evolved stars in our Galaxy and in the Magellanic Clouds, we are modeling mass loss from AGB and RSG stars in these galaxies. Our approach is twofold. We pursue radiative transfer modeling of the spectral energy distributions (SEDs) of AGB and RSG stars in the Large Magellanic Cloud (LMC), in the Small Magellanic Cloud (SMC), and in the Galactic bulge and in globular clusters of the Milky Way. We are also constructing detailed dust opacity models of AGB and RSG stars in these galaxies for which we have infrared spectra; e.g., from the Spitzer Space Telescope Infrared Spectrograph (IRS). Our sample of infrared spectra largely comes from Spitzer-IRS observations. The detailed dust modeling of spectra informs our choice of dust properties to use in radiative transfer modeling of SEDs. We seek to determine how mass loss from these evolved stars depends upon the metallicity of their host environments. BAS acknowledges funding from NASA ADAP grant NNX15AF15G.

Variability of Massive Young Stellar Objects in Cygnus-X

NASA Astrophysics Data System (ADS)

Thomas, Nancy H.; Hora, J. L.; Smith, H. A.

2013-01-01

Young stellar objects (YSOs) are stars in the process of formation. Several recent investigations have shown a high rate of photometric variability in YSOs at near- and mid-infrared wavelengths. Theoretical models for the formation of massive stars (1-10 solar masses) remain highly idealized, and little is known about the mechanisms that produce the variability. An ongoing Spitzer Space Telescope program is studying massive star formation in the Cygnus-X region. In conjunction with the Spitzer observations, we have conducted a ground-based near-infrared observing program of the Cygnus-X DR21 field using PAIRITEL, the automated infrared telescope at Whipple Observatory. Using the Stetson index for variability, we identified variable objects and a number of variable YSOs in our time-series PAIRITEL data of DR21. We have searched for periodicity among our variable objects using the Lomb-Scargle algorithm, and identified periodic variable objects with an average period of 8.07 days. Characterization of these variable and periodic objects will help constrain models of star formation present. This work is supported in part by the NSF REU and DOD ASSURE programs under NSF grant no. 0754568 and by the Smithsonian Institution.

Is There Anybody Home?

NASA Image and Video Library

2004-12-09

NASA's Spitzer Space Telescope recently captured these infrared images of six older stars with known planets. The yellow, fuzzy blobs are stars circled by disks of dust, or "debris disks," like the one that surrounds our own Sun. Though astronomers had predicted that stars with planets would harbor debris disks, they could not detect such disks until now. Spitzer was able to sense these dusty disks via their warm infrared glows. Specifically, the presence of the disks was inferred from an excess amount of infrared emission relative to what is emitted from the parent star alone. The stars themselves are similar in age and temperature to our Sun. In astronomical terms, they are stellar main sequence stars, with spectral types of F, G, or K. These planet-bearing stars have a median age of four billion years. For reference, our Sun is classified as a G star, with an age of approximately five billion years. The disks surrounding these planetary systems are comprised of cool material, with temperatures less than 100 Kelvin (-173 degrees Celsius). They are10 times farther away from their parent stars than Earth is from the Sun, and are thought to be analogues of the comet-filled Kuiper Belt in our solar system. The contrast scale is the same for each image. The images are approximately 2 arcminutes on each side. North is oriented upward and east is to the left. The pictures were taken with the 70-micron filter of Spitzer's multiband imaging photometer. The telescope resolution at 70 microns is 17 arcseconds and there is no evidence for any emission extended beyond the telescope resolution. http://photojournal.jpl.nasa.gov/catalog/PIA07098

Is There Anybody Home?

NASA Technical Reports Server (NTRS)

2004-01-01

[figure removed for brevity, see original site] Figure 1

NASA's Spitzer Space Telescope recently captured these infrared images of six older stars with known planets. The yellow, fuzzy blobs are stars circled by disks of dust, or 'debris disks,' like the one that surrounds our own Sun. Though astronomers had predicted that stars with planets would harbor debris disks, they could not detect such disks until now.

Spitzer was able to sense these dusty disks via their warm infrared glows. Specifically, the presence of the disks was inferred from an excess amount of infrared emission relative to what is emitted from the parent star alone.

The stars themselves are similar in age and temperature to our Sun. In astronomical terms, they are stellar main sequence stars, with spectral types of F, G, or K. These planet-bearing stars have a median age of four billion years. For reference, our Sun is classified as a G star, with an age of approximately five billion years.

The disks surrounding these planetary systems are comprised of cool material, with temperatures less than 100 Kelvin (-173 degrees Celsius). They are10 times farther away from their parent stars than Earth is from the Sun, and are thought to be analogues of the comet-filled Kuiper Belt in our solar system.

The contrast scale is the same for each image. The images are approximately 2 arcminutes on each side. North is oriented upward and east is to the left. The pictures were taken with the 70-micron filter of Spitzer's multiband imaging photometer. The telescope resolution at 70 microns is 17 arcseconds and there is no evidence for any emission extended beyond the telescope resolution.

Identification and Classification of Infrared Excess Sources in the Spitzer Enhanced Imaging Products (SEIP) Catalog

NASA Astrophysics Data System (ADS)

Strasburger, David; Gorjian, Varoujan; Burke, Todd; Childs, Linda; Odden, Caroline; Tambara, Kevin; Abate, Antoinette; Akhtar, Nadir; Beach, Skyler; Bhojwani, Ishaan; Brown, Caden; Dear, AnnaMaria; Dumont, Theodore; Harden, Olivia; Joli-Coeur, Laurent; Nahirny, Rachel; Nakahira, Andie; Nix, Sabine; Orgul, Sarp; Parry, Johnny; Picken, John; Taylor, Isabel; Toner, Emre; Turner, Aspen; Xu, Jessica; Zhu, Emily

2015-01-01

The Spitzer Space Telescope's original cryogenic mission imaged roughly 42 million sources, most of which were incidental and never specifically targeted for research. These have now been compiled in the publicly accessible Spitzer Enhanced Imaging Products (SEIP) catalog. The SEIP stores millions of never before examined sources that happened to be in the same field of view as objects specifically selected for study. This project examined the catalog to isolate previously unknown infrared excess (IRXS) candidates. The culling process utilized four steps. First, we considered only those objects with signal to noise ratios of at least 10 to 1 in the following five wavelengths: 3.6, 4.5, 5.8, 8 and 24 microns, which narrowed the source list to about one million. Second, objects were removed from highly studied regions, such as the galactic plane and previously conducted infrared surveys. This further reduced the population of sources to 283,758. Third, the remaining sources were plotted using a [3.6]-[4.5] vs. [8]-[24] color-color diagram to isolate IRXS candidates. Fourth, multiple images of sixty-three outlier points from the extrema of the color-color diagram were examined to verify that the sources had been cross matched correctly and to exclude any candidate sources that may have been compromised due to image artifacts or field crowding. The team will ultimately provide statistics for the prevalence of IRXS sources in the SEIP catalog and provide analysis of those extreme outliers from the main locus of points. This research was made possible through the NASA/IPAC Teacher Archive Research Program (NITARP) and was funded by NASA Astrophysics Data Program.

EVLA Observation of Centimeter Continuum Emission from Protostars in Serpens South

NASA Astrophysics Data System (ADS)

Kern, Nicholas S.; Tobin, John J.; Keown, Jared A.; Gutermuth, Robert A.

2015-01-01

Serpens South is a protocluster with an unusually high abundance of Class 0 and I protostars, suggesting it is in a very early phase of star formation and may eventually form a star cluster. Following its discovery in 2008 with the Spitzer space telescope, infrared and millimeter observations and analysis quickly followed, however, Serpens South has yet to be fully explored in the radio. Radio observations at centimeter wavelengths have long been used as a tool to probe the dynamical processes of young protostars that are still heavily shrouded in their protostellar envelopes and thus cannot be seen at longer wavelengths. Radio observations then become an important tool in understanding Serpens South due to its young age. To this end, we have conducted EVLA C band continuum observations of the central region of the Serpens South protostellar cluster in order to map the centimeter continuum emission in a region of high Class 0 / I protostellar surface density. We report the detection of centimeter emission corresponding to protostars identified by Spitzer, and to protostars identified but blended by Herschel. We characterize their centimeter emission, and put them in context with previous Spitzer and Herschel infrared and far-infrared observations, as well as IRAM millimeter observations. Additionally, we make an assessment of the protostars' bolometric luminosity, and compare them to the known protostellar 3.6 cm to 6.0 cm luminosity vs. bolometric luminosity relation. With the EVLA, we present a mid-resolution map of centimeter emission from the central region of Serpens South with the highest sensitivity to date, with a beam size of ~5 arcseconds and rms on the order of 15 microJansky.

Probing Cosmic Star Formation Using Long Gamma-Ray Bursts: New Constraints from the Spitzer Space Telescope

NASA Astrophysics Data System (ADS)

Le Floc'h, Emeric; Charmandaris, Vassilis; Forrest, William J.; Mirabel, I. Félix; Armus, Lee; Devost, Daniel

2006-05-01

We report on IRAC 4.5 μm, IRAC 8.0 μm, and MIPS 24 μm deep observations of 16 gamma-ray burst (GRB) host galaxies performed with the Spitzer Space Telescope, and we investigate in the thermal infrared the presence of evolved stellar populations and dust-enshrouded star-forming activity associated with these objects. Our sample is derived from GRBs that were identified with subarcsecond localization between 1997 and 2001, and only a very small fraction (~20%) of the targeted sources are detected down to f4.5μm~3.5 μJy and f24μm~85 μJy (3 σ). This likely argues against a population dominated by massive and strongly starbursting (i.e., SFR>~100 Msolar yr-1) galaxies as has been recently suggested from submillimeter/radio and optical studies of similarly selected GRB hosts. Furthermore, we find evidence that some GRBs do not occur in the most infrared luminous regions-hence the most actively star-forming environments-of their host galaxies. Should the GRB hosts be representative of all star-forming galaxies at high redshift, models of infrared galaxy evolution indicate that >~50% of GRB hosts should have f24μm>~100 μJy. Unless the identification of GRBs prior to 2001 was prone to strong selection effects biasing our sample against dusty galaxies, we infer in this context that the GRBs identified with the current techniques cannot be directly used as unbiased probes of the global and integrated star formation history of the universe. Based on observations made with the Spitzer Space Telescope, operated by the Jet Propulsion Laboratory under NASA contract 1407.

RESOLVING THE ACTIVE GALACTIC NUCLEUS AND HOST EMISSION IN THE MID-INFRARED USING A MODEL-INDEPENDENT SPECTRAL DECOMPOSITION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hernán-Caballero, Antonio; Alonso-Herrero, Almudena; Hatziminaoglou, Evanthia

2015-04-20

We present results on the spectral decomposition of 118 Spitzer Infrared Spectrograph (IRS) spectra from local active galactic nuclei (AGNs) using a large set of Spitzer/IRS spectra as templates. The templates are themselves IRS spectra from extreme cases where a single physical component (stellar, interstellar, or AGN) completely dominates the integrated mid-infrared emission. We show that a linear combination of one template for each physical component reproduces the observed IRS spectra of AGN hosts with unprecedented fidelity for a template fitting method with no need to model extinction separately. We use full probability distribution functions to estimate expectation values andmore » uncertainties for observables, and find that the decomposition results are robust against degeneracies. Furthermore, we compare the AGN spectra derived from the spectral decomposition with sub-arcsecond resolution nuclear photometry and spectroscopy from ground-based observations. We find that the AGN component derived from the decomposition closely matches the nuclear spectrum with a 1σ dispersion of 0.12 dex in luminosity and typical uncertainties of ∼0.19 in the spectral index and ∼0.1 in the silicate strength. We conclude that the emission from the host galaxy can be reliably removed from the IRS spectra of AGNs. This allows for unbiased studies of the AGN emission in intermediate- and high-redshift galaxies—currently inaccesible to ground-based observations—with archival Spitzer/IRS data and in the future with the Mid-InfraRed Instrument of the James Webb Space Telescope. The decomposition code and templates are available at http://denebola.org/ahc/deblendIRS.« less

Star Formation in the DR21 Region (B)

NASA Technical Reports Server (NTRS)

2004-01-01

[figure removed for brevity, see original site] Annotated mosaic

Hidden behind a shroud of dust in the constellation Cygnus is an exceptionally bright source of radio emission called DR21. Visible light images reveal no trace of what is happening in this region because of heavy dust obscuration. In fact, visible light is attenuated in DR21 by a factor of more than 10,000,000,000,000,000,000,000,000,000,000,000,000,000 (ten thousand trillion heptillion).

New images from NASA's Spitzer Space Telescope allow us to peek behind the cosmic veil and pinpoint one of the most massive natal stars yet seen in our Milky Way galaxy. The never-before-seen star is 100,000 times as bright as the Sun. Also revealed for the first time is a powerful outflow of hot gas emanating from this star and bursting through a giant molecular cloud.

The upper image is a large-scale mosaic assembled from individual photographs obtained with the InfraRed Array Camera (IRAC) aboard Spitzer. The image covers an area about two times that of a full moon. The mosaic is a composite of images obtained at mid-infrared wavelengths of 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange) and 8 microns (red). The brightest infrared cloud near the top center corresponds to DR21, which presumably contains a cluster of newly forming stars at a distance of 10,000 light-years.

Protruding out from DR21 toward the bottom left of the image is a gaseous outflow (green), containing both carbon monoxide and molecular hydrogen. Data from the Spitzer spectrograph, which breaks light into its constituent individual wavelengths, indicate the presence of hot steam formed as the outflow heats the surrounding molecular gas. Outflows are physical signatures of processes that create supersonic beams, or jets, of gas. They are usually accompanied by discs of material around the new star, which likely contain the materials from which future planetary systems are formed. Additional newborn stars, depicted in green, can be seen surrounding the DR21 region.

The red filaments stretching across this image denote the presence of polycyclic aromatic hydrocarbons. These organic molecules, comprised of carbon and hydrogen, are excited by surrounding interstellar radiation and become luminescent at wavelengths near 8.0 microns. The complex pattern of filaments is caused by an intricate combination of radiation pressure, gravity and magnetic fields. The result is a tapestry in which winds, outflows and turbulence move and shape the interstellar medium.

To the lower left of the mosaic is a large bubble of gas and dust, which may represent the remnants of a past generation of stars.

The lower panel shows a 24-micron image mosaic, obtained with the Multiband Imaging Photometer aboard Spitzer (MIPS). This image maps the cooler infrared emission from interstellar dust found throughout the interstellar medium. The DR21 complex is clearly seen near the center of the strip, which covers about twice the area of the IRAC image.

Perhaps the most fascinating feature in this image is a long and shadowy linear filament extending towards the 10 o'clock position of DR21. This jet of cold and dense gas, nearly 50 light-years in extent, appears in silhouette against a warmer background. This filament is too long and massive to be a stellar jet and may have formed from a pre-existing molecular cloud core sculpted by DR21's strong winds. Regardless of its true nature, this jet and the numerous other arcs and wisps of cool dust signify the interstellar turbulence normally unseen by the human eye.

Obituary: Lynne Karen Deutsch, 1954-2004

NASA Astrophysics Data System (ADS)

Sprague, Ann L.

2004-12-01

It is with deep sadness and regret that we note the passing of our dear friend and colleague Prof. Lynne K. Deutsch. Lynne died on 2 April 2004 after a protracted illness and lengthy battle with complications caused by the blood disease Polycythaemia Vera. Lynne was born in Chicago on 26 November 1956 to Victor and Ailsa Deutsch. She lived with her family in the town of Morton Grove, IL until she was 8 years old, when they moved to Beverly Hills, CA. She was an outgoing child who played basketball and excelled in her studies. She graduated from Beverly Hills High School at the age of 16 after completing all high school requirements in only three years. Lynne had a beautiful singing voice, and was in the chorus in high school and college. Lynne earned her first bachelor's degree in philosophy from the University of California at Berkeley in 1977. She then returned to Berkeley and received a second bachelor's degree, this time in physics, in 1981. She was a graduate student and teaching assistant at MIT and earned an MS in physics from MIT in 1983. Lynne then attended the astronomy graduate program at Harvard University, where she earned her MA in 1985 and PhD in 1990. During her degree studies she began crafting mid-infrared instrumentation. These instruments were destined to be used by a host of eager observers to discover, identify, and study many emissions from the Solar System, and galactic and extragalactic sources. Lynne was a National Research Council Post-doctoral Fellow at NASA Ames Research Center from 1990 - 1992, where she played an important role in the development of the Smithsonian Astrophysical Observatory/University of Arizona Mid-Infrared Array Camera (MIRAC), a well-known and much sought after instrument frequently used in studies of Mercury, Jupiter, the Moon, planetary nebulae, star formation regions, galactic center, young stellar objects, and extragalactic objects. After leaving NASA Ames Research Center, Lynne taught for several years (1993-96) at Smith College where she had a significant impact on undergraduate research, especially for women, whom she enjoyed mentoring. Lynne joined the faculty in the Astronomy Department of Boston University in 1996 where she taught instrumentation principles and techniques to undergraduate and graduate students. Over the course of her faculty career, she received numerous research grants and fellowships that were used to support her research, her students, and her postdoctoral associates. She was the principal investigator of Boston University's advanced technologies and instrumentation program MIRABU: A Mid-Infrared Array. As her health declined and the rigors of a full teaching schedule became unacceptably taxing, Lynne took a leave of absence from Boston University and returned to Harvard University and the Center for Astrophysics in 2001. There she became a very active member of the Infrared Group in the OIR Division and a member of the IRAC/Spitzer Space Telescope team. Her research in infrared astronomy covered many areas including star formation, planetary and protoplanetary nebulae, solar system objects, the interstellar medium and infrared-luminous galaxies. Her most recent research with the Infrared Array Camera (IRAC) on the Spitzer Space Telescope concentrated on high-mass star formation and the related evolution of the interstellar medium. In her short life, Lynne made many devoted friends and colleagues and was active in encouraging school-age girls to pursue their interests in the sciences. In her short career, she published more than seventy-five articles. She was an outstanding observer and instrumentalist, whose promising career was tragically cut short. Lynne was also a devoted mother and wife, and, while still well, she found the time to be an active participant in her son's elementary school. She is very greatly missed by her family. She is survived by her husband Douglas Sondak, PhD and her son Reed Deutsch-Sondak who live in Acton, MA, and her parents and sister Judith who reside in California. Lynne will be forever missed by her family, friends, colleagues, and the astronomical community. Her contributions will continue to benefit the community for many years to come. We only wish she were here to share them with us. She will be remembered as a dear friend, colleague, accomplished scientist, and dedicated family member.

Exoplanet Forecast: Hot and Wet

NASA Technical Reports Server (NTRS)

2007-01-01

[figure removed for brevity, see original site] Click on image for larger poster version

This plot of data from NASA's Spitzer Space Telescope tells astronomers that a toasty gas exoplanet, or a planet beyond our solar system, contains water vapor.

Spitzer observed the planet, called HD 189733b, cross in front of its star at three different infrared wavelengths: 3.6 microns; 4.5 microns and 8 microns (see lime-colored dots). For each wavelength, the planet's atmosphere absorbed different amounts of the starlight that passed through it. The pattern by which this absorption varies with wavelength matches known signatures of water, as shown by the theoretical model in blue.

VizieR Online Data Catalog: Spitzer photometry of ~1million stars in M31 & 15 gal. (Khan, 2017)

NASA Astrophysics Data System (ADS)

Khan, R.

2017-03-01

For M31, we used the IRAC 3.6, 4.5, 5.8, and 8um mosaics produced by Mould+ (2008, J/ApJ/687/230) and the MIPS 24um mosaic produced by Gordon+ (2006ApJ...638L..87G). For the other galaxies, we used the IRAC and MIPS mosaics produced by the Spitzer Infrared Nearby Galaxies Survey (SINGS; Kennicutt+ 2003PASP..115..928K) and the Local Volume Legacy Survey (LVL; Dale+ 2009, J/ApJ/703/517). We utilize the full mosaics available for each galaxy. (17 data files).

Spitzer Space Telescope Mid-IR Light Curves of Neptune

NASA Technical Reports Server (NTRS)

Stauffer, John; Marley, Mark S.; Gizis, John E.; Rebull, Luisa; Carey, Sean J.; Krick, Jessica; Ingalls, James G.; Lowrance, Patrick; Glaccum, William; Kirkpatrick, J. Davy;

Submm/mm galaxy counterpart identification using a characteristic density distribution

NASA Astrophysics Data System (ADS)

Alberts, Stacey; Wilson, Grant W.; Lu, Yu; Johnson, Seth; Yun, Min S.; Scott, Kimberly S.; Pope, Alexandra; Aretxaga, Itziar; Ezawa, Hajime; Hughes, David H.; Kawabe, Ryohei; Kim, Sungeun; Kohno, Kotaro; Oshima, Tai

2013-05-01

We present a new submm/mm galaxy counterpart identification technique which builds on the use of Spitzer Infrared Array Camera (IRAC) colours as discriminators between likely counterparts and the general IRAC galaxy population. Using 102 radio- and Submillimeter Array-confirmed counterparts to AzTEC sources across three fields [Great Observatories Origins Deep Survey-North, -South and Cosmic Evolution Survey (COSMOS)], we develop a non-parametric IRAC colour-colour characteristic density distribution, which, when combined with positional uncertainty information via likelihood ratios, allows us to rank all potential IRAC counterparts around submillimetre galaxies (SMGs) and calculate the significance of each ranking via the reliability factor. We report all robust and tentative radio counterparts to SMGs, the first such list available for AzTEC/COSMOS, as well as the highest ranked IRAC counterparts for all AzTEC SMGs in these fields as determined by our technique. We demonstrate that the technique is free of radio bias and thus applicable regardless of radio detections. For observations made with a moderate beam size (˜18 arcsec), this technique identifies ˜85 per cent of SMG counterparts. For much larger beam sizes (≳30 arcsec), we report identification rates of 33-49 per cent. Using simulations, we demonstrate that this technique is an improvement over using positional information alone for observations with facilities such as AzTEC on the Large Millimeter Telescope and Submillimeter Common User Bolometer Array 2 on the James Clerk Maxwell Telescope.

Near-infrared Thermal Emission from TrES-3b: A Ks-band Detection and an H-band Upper Limit on the Depth of the Secondary Eclipse

NASA Astrophysics Data System (ADS)

Croll, Bryce; Jayawardhana, Ray; Fortney, Jonathan J.; Lafrenière, David; Albert, Loic

2010-08-01

We present H- and Ks-band photometry bracketing the secondary eclipse of the hot Jupiter TrES-3b using the Wide-field Infrared Camera on the Canada-France-Hawaii Telescope. We detect the secondary eclipse of TrES-3b with a depth of 0.133+0.018 -0.016% in the Ks band (8σ)—a result that is in sharp contrast to the eclipse depth reported by de Mooij & Snellen. We do not detect its thermal emission in the H band, but place a 3σ limit of 0.051% on the depth of the secondary eclipse in this band. A secondary eclipse of this depth in Ks requires very efficient day-to-nightside redistribution of heat and nearly isotropic reradiation, a conclusion that is in agreement with longer wavelength, mid-infrared Spitzer observations. Our 3σ upper limit on the depth of our H-band secondary eclipse also argues for very efficient redistribution of heat and suggests that the atmospheric layer probed by these observations may be well homogenized. However, our H-band upper limit is so constraining that it suggests the possibility of a temperature inversion at depth, or an absorbing molecule, such as methane, that further depresses the emitted flux at this wavelength. The combination of our near-infrared measurements and those obtained with Spitzer suggests that TrES-3b displays a near-isothermal dayside atmospheric temperature structure, whose spectrum is well approximated by a blackbody. We emphasize that our strict H-band limit is in stark disagreement with the best-fit atmospheric model that results from longer wavelength observations only, thus highlighting the importance of near-infrared observations at multiple wavelengths, in addition to those returned by Spitzer in the mid-infrared, to facilitate a comprehensive understanding of the energy budgets of transiting exoplanets. Based on observations obtained with WIRCam, a joint project of CFHT, Taiwan, Korea, Canada, France, at the Canada-France-Hawaii Telescope (CFHT) which is operated by the National Research Council (NRC) of Canada, the Institute National des Sciences de l'Univers of the Centre National de la Recherche Scientifique of France, and the University of Hawaii.

Spitzer Space Telescope Sequencing Operations Software, Strategies, and Lessons Learned

NASA Technical Reports Server (NTRS)

Bliss, David A.

2006-01-01

The Space Infrared Telescope Facility (SIRTF) was launched in August, 2003, and renamed to the Spitzer Space Telescope in 2004. Two years of observing the universe in the wavelength range from 3 to 180 microns has yielded enormous scientific discoveries. Since this magnificent observatory has a limited lifetime, maximizing science viewing efficiency (ie, maximizing time spent executing activities directly related to science observations) was the key operational objective. The strategy employed for maximizing science viewing efficiency was to optimize spacecraft flexibility, adaptability, and use of observation time. The selected approach involved implementation of a multi-engine sequencing architecture coupled with nondeterministic spacecraft and science execution times. This approach, though effective, added much complexity to uplink operations and sequence development. The Jet Propulsion Laboratory (JPL) manages Spitzer s operations. As part of the uplink process, Spitzer s Mission Sequence Team (MST) was tasked with processing observatory inputs from the Spitzer Science Center (SSC) into efficiently integrated, constraint-checked, and modeled review and command products which accommodated the complexity of non-deterministic spacecraft and science event executions without increasing operations costs. The MST developed processes, scripts, and participated in the adaptation of multi-mission core software to enable rapid processing of complex sequences. The MST was also tasked with developing a Downlink Keyword File (DKF) which could instruct Deep Space Network (DSN) stations on how and when to configure themselves to receive Spitzer science data. As MST and uplink operations developed, important lessons were learned that should be applied to future missions, especially those missions which employ command-intensive operations via a multi-engine sequence architecture.

The Light and Dark Sides of a Distant Planet

NASA Image and Video Library

2006-10-12

The top graph consists of infrared data from NASA Spitzer Space Telescope. It tells astronomers that a distant planet, called Upsilon Andromedae b, always has a giant hot spot on the side that faces the star, while the other side is cold and dark.

A Bubble Bursts

NASA Technical Reports Server (NTRS)

2005-01-01

RCW 79 is seen in the southern Milky Way, 17,200 light-years from Earth in the constellation Centaurus. The bubble is 70-light years in diameter, and probably took about one million years to form from the radiation and winds of hot young stars.

The balloon of gas and dust is an example of stimulated star formation. Such stars are born when the hot bubble expands into the interstellar gas and dust around it. RCW 79 has spawned at least two groups of new stars along the edge of the large bubble. Some are visible inside the small bubble in the lower left corner. Another group of baby stars appears near the opening at the top.

NASA's Spitzer Space Telescope easily detects infrared light from the dust particles in RCW 79. The young stars within RCW 79 radiate ultraviolet light that excites molecules of dust within the bubble. This causes the dust grains to emit infrared light that is detected by Spitzer and seen here as the extended red features.

Studying the Fading Infrared Evolution of SN 1978K

NASA Astrophysics Data System (ADS)

Smith, Ian

2018-05-01

SN 1978K in the nearby barred spiral galaxy NGC 1313 is a remarkable Type IIn supernova that remains bright at X-ray through radio wavelengths 40 years after its explosion. Our long-term program of multi-wavelength observations is probing the dense medium that was ejected by the progenitor star, possibly a Luminous Blue Variable. Only SN 1978K was detected in a search for warm dust in supernovae in the transitional phase (age 10-100 years). Thus SN 1978K is a prime target for studying whether supernovae such as this are important contributors to the Universal dust budget and how the dust reacts to the strong and varying UV and X-ray emissions. Our analysis of the previous Spitzer observations shows a rapid fading of the warm dust emission. Here we request one Spitzer observation at 3.6 and 4.5 microns to continue to monitor the infrared evolution. This will serve as a bridge to future monitoring with JWST.

Polluted White Dwarf (Artist's Concept)

NASA Image and Video Library

2017-11-01

This artist's concept shows an exoplanet and debris disk orbiting a polluted white dwarf. White dwarfs are dim, dense remnants of stars similar to the Sun that have exhausted their nuclear fuel and blown off their outer layers. By "pollution," astronomers mean heavy elements invading the photospheres -- the outer atmospheres -- of these stars. The leading explanation is that exoplanets could push small rocky bodies toward the star, whose powerful gravity would pulverize them into dust. That dust, containing heavy elements from the torn-apart body, would then fall on the star. NASA's Spitzer Space Telescope has been instrumental in expanding the field of polluted white dwarfs orbited by hot, dusty disks. Since launch in 2004, Spitzer has confirmed about 40 of these special stars. Another space telescope, NASA's Wide-field Infrared Survey Explorer (WISE), also detected a handful, bringing the total up to about four dozen known today. Because these objects are so faint, infrared light is crucial to identifying them. https://photojournal.jpl.nasa.gov/catalog/PIA22084

Search For Debris Disks Around A Few Radio Pulsars

NASA Astrophysics Data System (ADS)

Wang, Zhongxiang; Kaplan, David; Kaspi, Victoria

2007-05-01

We propose to observe 7 radio pulsars with Spitzer/IRAC at 4.5 and 8.0 microns, in an effort to probe the general existence of debris disks around isolated neutron stars. Such disks, probably formed from fallback or pushback material left over from supernova explosions, has been suggested to be associated with various phenomena seen in radio pulsars. Recently, new evidence for such a disk around an isolated young neutron star was found in Spitzer observations of an X-ray pulsar. If they exist, the disks could be illuminated by energy output from central pulsars and thus be generally detectable in the infrared by IRAC. We have selected 40 relatively young, energetic pulsars from the most recent pulsar catalogue as the preliminary targets for our ground-based near-IR imaging survey. Based on the results from the survey observations, 7 pulsars are further selected because of their relatively sparse field and estimated low extinction. Combined with our near-IR images, Spitzer/IRAC observations will allow us to unambiguously identify disks if they are detected at the source positions. This Spitzer observation program we propose here probably represents the best test we can do on the general existence of disks around radio pulsars.

Mysterious Blob Galaxies Revealed

NASA Image and Video Library

2005-01-11

This image composite shows a giant galactic blob (red) and the three merging galaxies NASA's Spitzer Space Telescope discovered within it (yellow). Blobs are intensely glowing clouds of hot hydrogen gas that envelop faraway galaxies. They are about 10 times as large as the galaxies they surround. Visible-light images reveal the vast extent of blobs, but don't provide much information about their host galaxies. Using its heat-seeking infrared eyes, Spitzer was able to see the dusty galaxies tucked inside one well-known blob located 11 billion light-years away. The findings reveal three monstrously bright galaxies, trillions of times brighter than the Sun, in the process of merging together. Spitzer also observed three other blobs located in the same cosmic neighborhood, all of which were found to be glaringly bright. One of these blobs is also known to be a galactic merger, only between two galaxies instead of three. It remains to be seen whether the final two blobs studied also contain mergers. The Spitzer data were acquired by its multiband imaging photometer. The visible-light image was taken by the Blanco Telescope at the Cerro Tololo Inter-American Observatory, Chile. http://photojournal.jpl.nasa.gov/catalog/PIA07220

Young stellar population and ongoing star formation in the H II complex Sh2-252

NASA Astrophysics Data System (ADS)

Jose, Jessy; Pandey, A. K.; Samal, M. R.; Ojha, D. K.; Ogura, K.; Kim, J. S.; Kobayashi, N.; Goyal, A.; Chauhan, N.; Eswaraiah, C.

2013-07-01

In this paper, an extensive survey of the star-forming complex Sh2-252 has been undertaken with an aim to explore its hidden young stellar population as well as to understand the structure and star formation history for the first time. This complex is composed of five prominent embedded clusters associated with the subregions A, C, E, NGC 2175s and Teu 136. We used Two Micron All Sky Survey-near-infrared and Spitzer-Infrared Array Camera, Multiband Imaging Photometer for Spitzer photometry to identify and classify the young stellar objects (YSOs) by their infrared (IR) excess emission. Using the IR colour-colour criteria, we identified 577 YSOs, of which, 163 are Class I, 400 are Class II and 14 are transition disc YSOs, suggesting a moderately rich number of YSOs in this complex. Spatial distribution of the candidate YSOs shows that they are mostly clustered around the subregions in the western half of the complex, suggesting enhanced star formation activity towards its west. Using the spectral energy distribution and optical colour-magnitude diagram-based age analyses, we derived probable evolutionary status of the subregions of Sh2-252. Our analysis shows that the region A is the youngest (˜0.5 Myr), the regions B, C and E are of similar evolutionary stage (˜1-2 Myr) and the clusters NGC 2175s and Teu 136 are slightly evolved (˜2-3 Myr). Morphology of the region in the 1.1 mm map shows a semicircular shaped molecular shell composed of several clumps and YSOs bordering the western ionization front of Sh2-252. Our analyses suggest that next generation star formation is currently under way along this border and that possibly fragmentation of the matter collected during the expansion of the H II region as one of the major processes is responsible for such stars. We observed the densest concentration of YSOs (mostly Class I, ˜0.5 Myr) at the western outskirts of the complex, within a molecular clump associated with water and methanol masers and we suggest that it is indeed a site of cluster formation at a very early evolutionary stage, sandwiched between the two relatively evolved CH II regions A and B.

Hypothetical Rejuvenated Planets Artist Concept

NASA Image and Video Library

2015-06-25

This artist's concept shows a hypothetical "rejuvenated" planet -- a gas giant that has reclaimed its youthful infrared glow. NASA's Spitzer Space Telescope found tentative evidence for one such planet around a dead star, or white dwarf, called PG 0010+280 (depicted as white dot in illustration). When planets are young, they are warm and toasty due to internal heat left over from their formation. Planets cool over time -- until they are possibly rejuvenated. The theory goes that this Jupiter-like planet, which orbits far from its star, would accumulate some of the material sloughed off by its star as the star was dying. The material would cause the planet to swell in mass. As the material fell onto the planet, it would heat up due to friction and glow with infrared light. The final result would be an old planet, billions of years in age, radiating infrared light as it did in its youth. Spitzer detected an excess infrared light around the white dwarf PG 0010+280. Astronomers aren't sure where the light is coming from, but one possibility is a rejuvenated planet. Future observations may help solve the mystery. A Jupiter-like planet is about ten times the size of a white dwarf. White dwarfs are about the size of Earth, so one white dwarf would easily fit into the Great Red Spot on Jupiter! http://photojournal.jpl.nasa.gov/catalog/PIA19346

The Fourier-Kelvin Stellar Interferometer (FKSI): Infrared Detection and Characterization of Exozodiacal Dust to Super-Earths, A Progress Report

NASA Technical Reports Server (NTRS)

Danchi, W.

2010-01-01

The Fourier-Kelvin Stellar Interferometer (FKSI) is a structurally connected infrared space interferometer with 0.5 m diameter telescopes on a 12.5 m baseline, and is passively cooled to approx.60K. The FKSI operates in the thermal infrared from 3-8 microns in a nulling (or starlight suppressing) mode for the detection and characterization of exoplanets, debris disks, extrasolar zodiacal dust levels. The FKSI will have the highest angular resolution of any infrared space instrument ever made with its nominal resolution of 40 mas at a 5 micron center wavelength. This resolution exceeds that of Spitzer by a factor of 38 and JWST by a factor of 5. The FKSI mission is conceived as a "probe class" or "mid-sized" strategic mission that utilizes technology advances from flagship projects like JWST, SIM, Spitzer, and the technology programs of TPF-I/Darwin. During the past year we began investigating an enhanced version of FKSI with 1-2 m diameter telescopes, passively cooled to 40K, on a 20-m baseline, with a sunshade giving a +/- 45 degree Field-of-Regard. This enhanced design is capable of detecting and characterizing the atmospheres of many 2 Earth-radius super-Earths and a few Earth-twins. We will report progress on the design of the enhanced mission concept and current status of the technologies needed for this mission.

Three Great Eyes on Kepler's Supernova Remnant

NASA Technical Reports Server (NTRS)

2004-01-01

[figure removed for brevity, see original site] Composite

[figure removed for brevity, see original site] [figure removed for brevity, see original site] Chandra X-Ray Data (blue) Chandra X-Ray Data (green)Hubble Telescope (visible-light)Spitzer Telescope (infrared)

NASA's three Great Observatories -- the Hubble Space Telescope, the Spitzer Space Telescope, and the Chandra X-ray Observatory -- joined forces to probe the expanding remains of a supernova, called Kepler's supernova remnant, first seen 400 years ago by sky watchers, including astronomer Johannes Kepler.

The combined image unveils a bubble-shaped shroud of gas and dust that is 14 light-years wide and is expanding at 4 million miles per hour (2,000 kilometers per second). Observations from each telescope highlight distinct features of the supernova remnant, a fast-moving shell of iron-rich material from the exploded star, surrounded by an expanding shock wave that is sweeping up interstellar gas and dust.

Each color in this image represents a different region of the electromagnetic spectrum, from X-rays to infrared light. These diverse colors are shown in the panel of photographs below the composite image. The X-ray and infrared data cannot be seen with the human eye. By color-coding those data and combining them with Hubble's visible-light view, astronomers are presenting a more complete picture of the supernova remnant.

Visible-light images from the Hubble telescope (colored yellow) reveal where the supernova shock wave is slamming into the densest regions of surrounding gas. The bright glowing knots are dense clumps from instabilities that form behind the shock wave. The Hubble data also show thin filaments of gas that look like rippled sheets seen edge-on. These filaments reveal where the shock wave is encountering lower-density, more uniform interstellar material.

The Spitzer telescope shows microscopic dust particles (colored red) that have been heated by the supernova shock wave. The dust re-radiates the shock wave's energy as infrared light. The Spitzer data are brightest in the regions surrounding those seen in detail by the Hubble telescope.

The Chandra X-ray data show regions of very hot gas, and extremely high-energy particles. The hottest gas (higher-energy X-rays, colored blue) is located primarily in the regions directly behind the shock front. These regions also show up in the Hubble observations, and also align with the faint rim of glowing material seen in the Spitzer data. The X-rays from the region on the lower left (colored blue) may be dominated by extremely high-energy electrons that were produced by the shock wave and are radiating at radio through X-ray wavelengths as they spiral in the intensified magnetic field behind the shock front. Cooler X-ray gas (lower-energy X-rays, colored green) resides in a thick interior shell and marks the location of heated material expelled from the exploded star.

Kepler's supernova, the last such object seen to explode in our Milky Way galaxy, resides about 13,000 light-years away in the constellation Ophiuchus.

The Chandra observations were taken in June 2000, the Hubble in August 2003; and the Spitzer in August 2004.

NASA's Great Observatories Celebrate the International Year of Astronomy

NASA Technical Reports Server (NTRS)

2009-01-01

[figure removed for brevity, see original site] Click on the image for larger version

In 1609, Galileo improved the newly invented telescope, turned it toward the heavens, and revolutionized our view of the universe. In celebration of the 400th anniversary of this milestone, 2009 has been designated as the International Year of Astronomy.

Today, NASA's Great Observatories are continuing Galileo's legacy with stunning images and breakthrough science from the Hubble Space Telescope, the Spitzer Space Telescope, and the Chandra X-ray Observatory.

While Galileo observed the sky using visible light seen by the human eye, technology now allows us to observe in many wavelengths, including Spitzer's infrared view and Chandra's view in X-rays. Each wavelength region shows different aspects of celestial objects and often reveals new objects that could not otherwise be studied.

This image of the spiral galaxy Messier 101 is a composite of views from Spitzer, Hubble, and Chandra. The red color shows Spitzer's view in infrared light. It highlights the heat emitted by dust lanes in the galaxy where stars can form. The yellow color is Hubble's view in visible light. Most of this light comes from stars, and they trace the same spiral structure as the dust lanes. The blue color shows Chandra's view in X-ray light. Sources of X-rays include million-degree gas, exploded stars, and material colliding around black holes.

Such composite images allow astronomers to see how features seen in one wavelength match up with those seen in another wavelength. It's like seeing with a camera, night vision goggles, and X-ray vision all at once.

In the four centuries since Galileo, astronomy has changed dramatically. Yet our curiosity and quest for knowledge remain the same. So, too, does our wonder at the splendor of the universe.

The International Year of Astronomy Great Observatories Image Unveiling is supported by the NASA Science Mission Directorate Astrophysics Division. The project is a collaboration between the Space Telescope Science Institute, the Spitzer Science Center, and the Chandra X-ray Center.

Constraints on the atmospheric circulation and variability of the eccentric hot Jupiter XO-3b

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wong, Ian; Knutson, Heather A.; Cowan, Nicolas B.

We report secondary eclipse photometry of the hot Jupiter XO-3b in the 4.5 μm band taken with the Infrared Array Camera on the Spitzer Space Telescope. We measure individual eclipse depths and center of eclipse times for a total of 12 secondary eclipses. We fit these data simultaneously with two transits observed in the same band in order to obtain a global best-fit secondary eclipse depth of 0.1580% ± 0.0036% and a center of eclipse phase of 0.67004 ± 0.00013. We assess the relative magnitude of variations in the dayside brightness of the planet by measuring the size of themore » residuals during ingress and egress from fitting the combined eclipse light curve with a uniform disk model and place an upper limit of 0.05%. The new secondary eclipse observations extend the total baseline from one and a half years to nearly three years, allowing us to place an upper limit on the periastron precession rate of 2.9 × 10{sup –3} deg day{sup –1}— the tightest constraint to date on the periastron precession rate of a hot Jupiter. We use the new transit observations to calculate improved estimates for the system properties, including an updated orbital ephemeris. We also use the large number of secondary eclipses to obtain the most stringent limits to date on the orbit-to-orbit variability of an eccentric hot Jupiter and demonstrate the consistency of multiple-epoch Spitzer observations.« less

IRSA

Science.gov Websites

Ipac_logo NASA/IPAC Infrared Science Archive Search for Source Search Radius 10 deg arcmin arcsec Guide for Solar System Observers Search Catalog: WISE 2MASS Spitzer Planck Herschel Gaia COSMOS PTF IRAS MSX AKARI Bolocam USNO DENIS Composite_Catalogs Contributed_Data_Sets INTERNALS Search Catalogs

AAS 227: Day 3

NASA Astrophysics Data System (ADS)

Kohler, Susanna

2016-01-01

Editors Note:This week were at the 227th AAS Meeting in Kissimmee, FL. Along with several fellow authors from astrobites.com, I will bewritingupdates on selectedevents at themeeting and posting at the end of each day. Follow along here or atastrobites.com, or catch ourlive-tweeted updates from the@astrobites Twitter account. The usual posting schedule for AAS Nova will resumenext week.Welcome to Day 3 of the winter American Astronomical Society (AAS) meeting in Kissimmee! Several of us are attending the conference this year, and we will report highlights from each day here on astrobites. If youd like to see more timely updates during the day, we encourage you to follow @astrobites on twitter or search the #aas227 hashtag.Henry Norris Russell Lecture: Viewing the Universe with Infrared Eyes: The Spitzer Space Telescope (by Erika Nesvold)The Henry Norris Russell Award is the highest honor given by the AAS, for a lifetime of eminence in astronomy research. This years award went to Giovanni Fazio of the Harvard-Smithsonian Center for Astrophysics. Fazio became a leader in gamma ray astronomy before switching mid-career to the study of infrared astronomy, and he gave his award lecture on the latter subject, specifically on the Spitzer Space Telescope, one of the most successful infrared telescopes of all time.Artists rendering of the Spitzer space telescope. [NASA/JPL-Caltech]Spitzer has been operating for more than twelve years, and has resulted in over six thousand papers in refereed journals in that time. The telescope sits in an Earth-trailing orbit around the Sun, and is now farther from the Earth (1.4 AU) than the Earth is from the Sun. Fazio gave the audience a fascinating overview of the science done by Spitzer over more than a decade. One of the most productive areas of research for Spitzer is the study of exoplanets, which hadnt even been discovered when the Spitzer Telescope was first conceived. Spitzers high sensitivity and ability to observe exoplanets over many orbits has made it a powerhouse for learning about the temperatures, atmospheres, and orbits of exoplanets. The list of examples that Fazio provided included the first global temperature map of an exoplanet (HD 189733b), the detection of the closest transiting exoplanet (HD 219134b), and the measurement of thermal emission from a super-Earth (55 Cnc e). Spitzers large distance from the Earth (specifically, the ground-based telescopes on Earth) even allowed astronomers to observe an exoplanet via gravitational microlensing using a special technique called space-based parallax.Spitzer has also been extremely useful for observing everything from Solar System scales (such as the enormous infrared dust ring around Saturn) to galactic structures. Comparing images of galaxies observed at visible wavelengths with Spitzer images of the same galaxies at infrared wavelengths has allowed us to probe the structure and composition of galaxies at a new level.Astronomers have also used Spitzer to explore the evolution of stars. Thanks to its infrared detectors, Spitzer can look through large clouds of dust that are opaque at visible wavelengths, and observe young stellar objects in their birth environments. Cosmologists can use Spitzer to study the early universe and the formation of galaxies over twelve billion years ago. Fazio used all of these examples and more to demonstrate that Spitzer has truly changed our understanding of the universe.Climate Change for Astronomers (Meredith Rawls)Every astronomer at #aas227 wants to learn about climate change! WOW this room is ridiculously full. pic.twitter.com/ud9an0gLJG Meredith Rawls (@merrdiff) January 7, 2016The second half of the session was a presentation by Doug Duncan featuring an activity from his 101-level college course. He uses climate change as a way to teach critical thinking and scientific reasoning. Members of the audience were walked through an exercise that included interpreting plots of changing surface temperatures, think-pair-share style clicker questions, and comparing excerpts from scientific articles and the media. Eventually, students discover that the Earths overall temperature is going up, but observations can vary from year to year because heat is moving between the atmosphere and the oceans.Press Conference: Fermis Vision, First Stars, Massive Galaxy Cluster, and Dark Energy (by Susanna Kohler)Todays afternoon press conference was an exciting assortment of results, difficult to categorize under a single umbrella.First up was Marco Ajello (Clemson University), who spoke about 2FHL, the second Fermi-LAT catalog of high-energy sources. LAT stands for Large Area Telescope, an instrument on board the Fermi gamma-ray space observatory that scans the entire sky every three hours. Ajello described the contents of the 2FHL catalog: 360 gamma-ray sources, of which 75% are blazars (distant galactic nuclei with jets pointed toward us), 11% are sources within the galaxy, and the remaining 14% are unknown. With this catalog, Fermi has expanded into higher energies than ever before, providing the first map of the 50 GeV 2 TeV sky. Heres the press release.OMeara: Im a lowly spectroscopist so I dont have fun pictures to show you, just squiggly lines. #aas227 astrobites (@astrobites) January 7, 2016Next to speak, John OMeara (St. Michaels College) told us about the discovery of a gas cloud that may be a remnant from the first population of stars. OMeara showed us the emission spectrum from a distant quasar, which displays abrupt absorption by a cloud of gas located at a redshift of z~3.5. Absorption by gas clouds is not unusual but what is unusual is that this cloud is extremely metal-poor, with only 1/2500th solar metallicity. This is the lowest heavy-element content ever measured, and a sign that the cloud might have been enriched by Population III stars the theoretical first population of stars, which were born when gas in the universe was still pristine. Heres the press release.Cluster IDCS J1426.5+3508. [NASA, European Space Agency, University of Florida, University of Missouri, and University of California]Mark Brodwin (University of Missouri, Kansas City) was up next, discussing the most distant massive galaxy cluster that has ever been discovered. The cluster IDCS J1426.5+3508, weighing in at several trillion solar masses (as measured by three independent techniques!), is located at a redshift of z=1.75. Since clusters take several billion years to form, and its redshift corresponds to a time when the universe was only 3.8 billion years old, were probably seeing it at a very early age. This combination of mass and youth is unique! Brodwin also pointed out another interesting feature: the clusters core isnt centered, which means it probably underwent a major merger with another cluster within the last 500 million years. Heres the press release.The final speaker was Sukanya Chakrabarti (Rochester Institute of Technology), who gave a very interesting talk about a topic Id never heard of: galactoseismology. Galactoseismology involves observing waves in the disk of a galaxy to learn about the properties of dwarf galaxies that caused the perturbations. In this case, Chakrabarti evaluated ripples in the outer disk of our galaxy, and used these to predict the location of a dwarf galaxy that must have skimmed the outskirts of our galaxy a few hundred million years ago, causing the waves. This is a cool technique for learning about dwarf galaxies whether or not theyre visible, since theyll cause ripples even if theyre dominated by dark matter. Chakrabarti showed an awesome simulation of this dwarfs interaction with the Milky Way, which you can check out on her website. Heres the press release.

Searching For Infrared Excesses Around White Dwarf Stars

NASA Astrophysics Data System (ADS)

Deeb Wilson, Elin; Rebull, Luisa M.; Debes, John H.; Stark, Chris

2017-01-01

Many WDs have been found to be “polluted,” meaning they contain heavier elements in their atmospheres. Either an active process that counters gravitational settling is taking place, or an external mechanism is the cause. One proposed external mechanism for atmospheric pollution of WDs is the disintegration and accretion of rocky bodies, which would result in a circumstellar (CS) disk. As CS disks are heated, they emit excess infrared (IR) emission. WDs with IR excesses indicative of a CS disk are known as dusty WDs. Statistical studies are still needed to determine how numerous dusty, polluted WDs are, along with trends and correlations regarding rate of planetary accretion, the lifetimes of CS disks, and the structure and evolution of CS disks. These findings will allow for a better understanding of the fates of planets along with potential habitability of surviving planets.In this work, we are trying to confirm IR excesses around a sample of 69 WD stars selected as part of the WISE InfraRed Excesses around Degenerates (WIRED) Survey (Debes et al. 2011). We have archival data from WISE, Spitzer, 2MASS, DENIS, and SDSS. The targets were initially selected from the Sloan Digital Sky Survey (SDSS), and identified as containing IR excesses based on WISE data. We also have data from the Four Star Infrared Camera array, which is part of Carnegie Institution’s Magellan 6.5 meter Baade Telescope located at Las Campanas Observatory in Chile. These Four Star data are much higher spatial resolution than the WISE data that were used to determine if each WD has an IR excess. There are often not many bands delineating the IR excess portion of the SED; therefore, we are using the Four Star data to check if there is another source in the WISE beam affecting the IR excess.

Hot, Dry and Cloudy

NASA Technical Reports Server (NTRS)

2007-01-01

[figure removed for brevity, see original site] Click on the image for movie of Hot, Dry and Cloudy

This artist's concept shows a cloudy Jupiter-like planet that orbits very close to its fiery hot star. NASA's Spitzer Space Telescope was recently used to capture spectra, or molecular fingerprints, of two 'hot Jupiter' worlds like the one depicted here. This is the first time a spectrum has ever been obtained for an exoplanet, or a planet beyond our solar system.

The ground-breaking observations were made with Spitzer's spectrograph, which pries apart infrared light into its basic wavelengths, revealing the 'fingerprints' of molecules imprinted inside. Spitzer studied two planets, HD 209458b and HD 189733b, both of which were found, surprisingly, to have no water in the tops of their atmospheres. The results suggest that the hot planets are socked in with dry, high clouds, which are obscuring water that lies underneath. In addition, HD209458b showed hints of silicates, suggesting that the high clouds on that planet contain very fine sand-like particles.

Capturing the spectra from the two hot-Jupiter planets was no easy feat. The planets cannot be distinguished from their stars and instead appear to telescopes as single blurs of light. One way to get around this is through what is known as the secondary eclipse technique. In this method, changes in the total light from a so-called transiting planet system are measured as a planet is eclipsed by its star, vanishing from our Earthly point of view. The dip in observed light can then be attributed to the planet alone.

This technique, first used by Spitzer in 2005 to directly detect the light from an exoplanet, currently only works at infrared wavelengths, where the differences in brightness between the planet and star are less, and the planet's light is easier to pick out. For example, if the experiment had been done in visible light, the total light from the system would appear to be unchanged, even as the planet disappeared from view.

To capture spectra of the planets, Spitzer observed their secondary eclipses with its spectrograph. It took a spectrum of a star together with its planet, then, as the planet disappeared from view, a spectrum of just the star. By subtracting the spectrum of the star from the spectrum of the star and planet together, astronomers were able to determine the spectrum of the planet itself.

Neither of the parent stars for HD 209458b or HD 189733b can be seen with the naked eye. HD 209458b is located about 153 light-years away in the constellation Pegasus, while HD 189733b is about 62 light-years away in the constellation Vulpecula. Both planets zip around their stars in very tight orbits; HD 209458b circles once every 3.5 days, while HD 189733b orbits once every 2.2 days.

Of the approximately 200 known exoplanets, there are 12 besides HD 209458b and HD 189733b whose orbits are inclined in such a way that, from our point of view, they pass in front of their stars. At least three of these transiting exoplanets are bright enough to follow in the footsteps of HD 209458b and HD 189733 and reveal their infrared spectra to Spitzer. Astronomers hope to use Spitzer's spectrograph in the future to study HD 209458b and HD 189733b again in much greater detail, and to examine some of the other candidates for the first time.

A Spitzer View of Star Formation in the Cyngus X North Complex

DTIC Science & Technology

2009-11-10

Sky Survey ( 2MASS ) data are used to identify and classify young stellar objects. Of the 8,231 sources detected exhibiting infrared excess in Cygnus X...Telescope. A combination of IRAC, MIPS, UKIRT Deep Infrared Sky Survey (UKIDSS), and Two Micron All Sky Survey ( 2MASS ) data are used to identify and classify...MIPS, Two-Micron All-Sky Survey ( 2MASS , Skrutskie et al. 2006) and UKIRT Deep Sky Survey DR4 (UKIDSS, Lawrence et al. 2007; Lucas et al. 2008

Modeling the evolution of infrared galaxies: a parametric backward evolution model

NASA Astrophysics Data System (ADS)

Béthermin, M.; Dole, H.; Lagache, G.; Le Borgne, D.; Penin, A.

2011-05-01

Aims: We attempt to model the infrared galaxy evolution in as simple a way as possible and reproduce statistical properties such as the number counts between 15 μm and 1.1 mm, the luminosity functions, and the redshift distributions. We then use the fitted model to interpret observations from Spitzer, AKARI, BLAST, LABOCA, AzTEC, SPT, and Herschel, and make predictions for Planck and future experiments such as CCAT or SPICA. Methods: This model uses an evolution in density and luminosity of the luminosity function parametrized by broken power-laws with two breaks at redshift ~0.9 and 2, and contains the two populations of the Lagache model: normal and starburst galaxies. We also take into account the effect of the strong lensing of high-redshift sub-millimeter galaxies. This effect is significant in the sub-mm and mm range near 50 mJy. It has 13 free parameters and eight additional calibration parameters. We fit the parameters to the IRAS, Spitzer, Herschel, and AzTEC measurements with a Monte Carlo Markov chain. Results: The model adjusted to deep counts at key wavelengths reproduces the counts from mid-infrared to millimeter wavelengths, as well as the mid-infrared luminosity functions. We discuss the contribution to both the cosmic infrared background (CIB) and the infrared luminosity density of the different populations. We also estimate the effect of the lensing on the number counts, and discuss the discovery by the South Pole Telescope (SPT) of a very bright population lying at high redshift. We predict the contribution of the lensed sources to the Planck number counts, the confusion level for future missions using a P(D) formalism, and the Universe opacity to TeV photons caused by the CIB. Material of the model (software, tables and predictions) is available online.

The Spitzer Infrared Nearby Galaxies Survey: A High-Resolution Spectroscopy Anthology

NASA Astrophysics Data System (ADS)

Dale, D. A.; Smith, J. D. T.; Schlawin, E. A.; Armus, L.; Buckalew, B. A.; Cohen, S. A.; Helou, G.; Jarrett, T. H.; Johnson, L. C.; Moustakas, J.; Murphy, E. J.; Roussel, H.; Sheth, K.; Staudaher, S.; Bot, C.; Calzetti, D.; Engelbracht, C. W.; Gordon, K. D.; Hollenbach, D. J.; Kennicutt, R. C.; Malhotra, S.

2009-03-01

High-resolution mid-infrared spectra are presented for 155 nuclear and extranuclear regions from the Spitzer Infrared Nearby Galaxies Survey (SINGS). The fluxes for nine atomic forbidden and three molecular hydrogen mid-infrared emission lines are also provided, along with upper limits in key lines for infrared-faint targets. The SINGS sample shows a wide range in the ratio of [S III] 18.71 μm/[S III] 33.48 μm, but the average ratio of the ensemble indicates a typical interstellar electron density of 300-400 cm-3 on ~23'' × 15'' scales and 500-600 cm-3 using ~11'' × 9'' apertures, independent of whether the region probed is a star-forming nuclear, a star-forming extranuclear, or an active galactic nuclei (AGN) environment. Evidence is provided that variations in gas-phase metallicity play an important role in driving variations in radiation field hardness, as indicated by [Ne III] 15.56 μm/[Ne II] 12.81 μm, for regions powered by star formation. Conversely, the radiation hardness for galaxy nuclei powered by accretion around a massive black hole is independent of metal abundance. Furthermore, for metal-rich environments AGN are distinguishable from star-forming regions by significantly larger [Ne III] 15.56 μm/[Ne II] 12.81 μm ratios. Finally, [Fe II] 25.99 μm/[Ne II] 12.81 μm versus [Si II] 34.82 μm/[S III] 33.48 μm also provides an empirical method for discerning AGN from normal star-forming sources. However, similar to [Ne III] 15.56 μm/[Ne II] 12.81 μm, these mid-infrared line ratios lose their AGN/star-formation diagnostic powers for very low metallicity star-forming systems with hard radiation fields.

A Year in the Life of an Infrared Echo

NASA Technical Reports Server (NTRS)

2005-01-01

[figure removed for brevity, see original site] Figure 1: Supernova Remnant Cassiopeia A One Year Apart

These Spitzer Space Telescope images, taken one year apart, show the supernova remnant Cassiopeia A (yellow ball) and surrounding clouds of dust (reddish orange). The pictures illustrate that a blast of light from Cassiopeia A is waltzing outward through the dusty skies. This dance, called an 'infrared echo,' began when the remnant erupted about 50 years ago.

Cassiopeia A is the remnant of a once massive star that died in a violent supernova explosion 325 years ago. It consists of a dead star, called a neutron star, and a surrounding shell of material that was blasted off as the star died. This remnant is located 10,000 light-years away in the northern constellation Cassiopeia.

Infrared echoes are created when a star explodes or erupts, flashing light into surrounding clumps of dust. As the light zips through the dust clumps, it heats them up, causing them to glow successively in infrared, like a chain of Christmas bulbs lighting up one by one. The result is an optical illusion, in which the dust appears to be flying outward at the speed of light. Echoes are distinct from supernova shockwaves, which are made up material that is swept up and hurled outward by exploding stars.

This infrared echo is the largest ever seen, stretching more than 50 light-years away from Cassiopeia A. If viewed from Earth, the entire movie frame would take up the same amount of space as two full moons.

Hints of an older infrared echo from Cassiopeia A's supernova explosion hundreds of years ago can also be seen.

The top Spitzer image was taken on November 30, 2003, and the bottom, on December 2, 2004.

Infrared Colors of Dwarf-Dwarf Galaxy Interactions

NASA Astrophysics Data System (ADS)

Liss, Sandra; Stierwalt, Sabrina; Johnson, Kelsey; Patton, Dave; Kallivayalil, Nitya

2015-10-01

We request Spitzer Warm Mission IRAC Channel 1 & 2 imaging for a sample of 60 isolated dwarf galaxy pairs as a key component of a larger, multi-wavelength effort to understand the role low-mass mergers play in galaxy evolution. A systematic study of dwarf-dwarf mergers has never been done, and we wish to characterize the impact such interactions have on fueling star formation in the nearby universe. The Spitzer imaging proposed here will allow us to determine the extent to which the 3.6 and 4.5 mum bands are dominated by stellar light and investigate a) the extent to which interacting pairs show IR excess and b) whether the excess is related to the pair separation. Second, we will use this IR photometry to constrain the processes contributing to the observed color excess and scatter in each system. We will take advantage of the wealth of observations available in the Spitzer Heritage Archive for 'normal' non-interacting dwarfs by comparing the stellar populations of those dwarfs with the likely interacting dwarfs in our sample. Ultimately, we can combine the Spitzer imaging proposed here with our current, ongoing efforts to obtain groundbased optical photometry to model the star formation histories of these dwarfs and to help constrain the timescales and impact dwarf-dwarf mergers have on fueling star formation. The sensitivity and resolution offered by Spitzer are necessary to determine the dust properties of these interacting systems, and how these properties vary as a function of pair separation, mass ratio, and gas fraction.

SPITZER SPACE TELESCOPE MID-IR LIGHT CURVES OF NEPTUNE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stauffer, John; Rebull, Luisa; Carey, Sean J.

2016-11-01

We have used the Spitzer Space Telescope in 2016 February to obtain high cadence, high signal-to-noise, 17 hr duration light curves of Neptune at 3.6 and 4.5 μ m. The light curve duration was chosen to correspond to the rotation period of Neptune. Both light curves are slowly varying with time, with full amplitudes of 1.1 mag at 3.6 μ m and 0.6 mag at 4.5 μ m. We have also extracted sparsely sampled 18 hr light curves of Neptune at W1 (3.4 μ m) and W2 (4.6 μ m) from the Wide-feld Infrared Survey Explorer ( WISE )/ NEOWISEmore » archive at six epochs in 2010–2015. These light curves all show similar shapes and amplitudes compared to the Spitzer light curves but with considerable variation from epoch to epoch. These amplitudes are much larger than those observed with Kepler / K 2 in the visible (amplitude ∼0.02 mag) or at 845 nm with the Hubble Space Telescope ( HST ) in 2015 and at 763 nm in 2016 (amplitude ∼0.2 mag). We interpret the Spitzer and WISE light curves as arising entirely from reflected solar photons, from higher levels in Neptune’s atmosphere than for K 2. Methane gas is the dominant opacity source in Neptune’s atmosphere, and methane absorption bands are present in the HST 763 and 845 nm, WISE W1, and Spitzer 3.6 μ m filters.« less

Creating a Teacher-Student Research Program Using the Spitzer Space Telescope

NASA Astrophysics Data System (ADS)

Daou, D.; Pompea, S.; Thaller, M.

2004-12-01

The Spitzer Science Center (SSC) and the National Optical Astronomy Observatory (NOAO) have created a program for teacher and student research using observing time on the Spitzer Space Telescope. The participating teachers attended a fall, 2004 workshop to become familiar with the Spitzer Space Telescope (SST) archives, and to receive training in infrared astronomy and observational techniques. The teachers will also attend a workshop offered by the SSC to learn about the observation planning process, and telescope and instrument capabilities. This program has as its goals the fundamental NASA goals of inspiring and motivating students to pursue careers in science, technology, engineering, and mathematics as well as to engage the public in shaping and sharing the experience of exploration and discovery. Our educational plan addresses the NASA objectives of improving student proficiency in science and improving science instruction by providing a unique opportunity to a group of teachers and students to observe with the SST and work with the SST archival data. This program allows a team of 12 teachers and their students to utilize up to 3 hours of Director's discretionary observing time on the Spitzer Space Telescope for educational observations. Leveraging on a well-established teacher professional development, the SSC is offering this program to teachers in the Teacher Leaders in Research Based Science Education (TLRRBSE), an ongoing program at the NOAO. This NSF-sponsored program touches the formal education community through a national audience of well-trained and supported middle and high school teachers. The Spitzer educational research program also reaches an additional national audience of students through an informal education program based at the University of Arizona's Astronomy Camp, directed by Dr. Don McCarthy. During this camp, the teachers and their students will learn about the SST through the vast amount of data available in the Spitzer archives.

Proceedings of the Second Infrared Detector Technology Workshop

NASA Technical Reports Server (NTRS)

Mccreight, C. R. (Compiler)

1986-01-01

The workshop focused on infrared detector, detector array, and cryogenic electronic technologies relevant to low-background space astronomy. Papers are organized into the following categories: discrete infrared detectors and readout electronics; advanced bolometers; intrinsic integrated infrared arrays; and extrinsic integrated infrared arrays. Status reports on the Space Infrared Telescope Facility (SIRTF) and Infrared Space Observatory (ISO) programs are also included.

Tracing Star Formation in the Mid-infrared

NASA Astrophysics Data System (ADS)

Wu, Ronin

One of the most important missions of the 20th century in astrophysics is the launch of the Spitzer Space Telescope in August 2003. Since then, with its unprecedented sensitivity and spatial resolution in the infrared, this earth--trailing satellite has significantly improved our understanding of star--formation history and the composition of the interstellar medium from an extragalactic perspective. In this thesis, I present the statistical studies of several star--formation tracers and properties of star--forming galaxies using the photometric and spectroscopic data taken by the Spitzer Space Telescope. The first approach I take in understanding the mid-infrared star--forming tracers is studying the aromatic features at 7.7mum. Aromatic features are the dominant emission lines in the mid-infrared spectra of star--forming galaxies, but these features are much weaker in galaxies of low--luminosity. I combine the infrared and the optical imaging data to demonstrate this trend. Comparison with optical spectroscopic data shows that the strength of the 7.7mum aromatic feature is closely related to the stellar mass of galaxies. Our analysis shows that both oxygen abundance and radiation hardness affect the strength of this feature. However, the generally low oxygen abundance in low--luminosity galaxy interstellar environments, which prevents the synthesis of aromatic molecules, appears to have the stronger effect. The second approach I take is the analysis of the Spitzer SDSS Statistical Spectroscopic Survey (S5), a multi-wavelength study of ˜300 homogeneously selected star--forming galaxies at redshifts 0.05 < z < 0.1. The S5 galaxies span the color range of the Sloan Digital Sky Survey and span two orders of magnitudes in stellar mass. The key goal of the survey is to provide a deeper understanding of the properties of warm interstellar medium by comparing the optical and mid-infrared spectra of galaxies that are structurally similar. The S5 survey contains a significant fraction of galaxies that show composite properties of star--forming and AGN. I explain the data analysis for this survey and present comparisons of optical and mid-infrared AGN/star--forming diagnostics and discuss possible heating mechanisms for aromatic features and molecular hydrogen in galaxies of different types. Molecular hydrogen is the simplest and most abundant molecule in the Universe. Stars are formed from molecular gas through gravitational condensation. The abundance of molecular hydrogen is a direct indicator for the star--forming ability of galaxies. In the third and last part of this thesis, I present the first mass function of molecular hydrogen directly measured using the molecule's rotational lines in the mid-infrared for galaxies in the homogeneously selected, S5 sample.

Infrared Studies of the Variability and Mass Loss of Dusty Asymptotic Giant Branch Stars in the Magellanic Clouds

NASA Astrophysics Data System (ADS)

Sargent, Benjamin; Groenewegen, M. A. T.

2018-01-01

The asymptotic giant branch (AGB) phase is one of the last phases of a star's life. AGB stars lose mass in an outflow in which dust condenses and is pushed away from the star. Extreme AGB stars are so named because their very red colors suggest very large amounts of dust, which in turn suggests extremely high mass loss rates. AGB stars also vary in brightness, and studies show that extreme AGB stars tend to have longer periods than other AGB stars and are more likely to be fundamental mode pulsators than other AGB stars. Extreme AGB stars are difficult to study, as their colors are so red due to their copious amounts of circumstellar dust that they are often not detected at optical wavelengths. Therefore, they must be observed at infrared wavelengths to explore their variability. Using the Spitzer Space Telescope, my team and I have observed a sample of extreme AGB stars in the Large Magellanic Cloud (LMC) and Small Magellanic Cloud (SMC) over Cycles 9 through 12 during the Warm Spitzer mission. For each cycle, we typically observed a set of extreme AGB stars at both 3.6 and 4.5 microns wavelength approximately monthly for most of a year. These observations reveal a wide range of variability properties. I present results from our analysis of the data obtained from these Spitzer variability programs, including light curve analyses and comparison to period-luminosity diagrams. Funding is acknowledged from JPL RSA # 1561703.

VizieR Online Data Catalog: Star formation in active and normal galaxies (Tsai+, 2015)

NASA Astrophysics Data System (ADS)

Tsai, M.; Hwang, C.-Y.

2015-11-01

We selected 104 active galaxies from the lists of Melendez et al. (2010MNRAS.406..493M), Condon et al. 1991 (cat. J/ApJ/378/65), and Ho & Ulvestad 2001 (cat. J/ApJS/133/77). Most of the sources are identified as Active Galactic Nuclei (AGNs), and a few of them are classified as Luminous InfraRed Galaxies (LIRGs). We obtained 3.6 and 8μm infrared images of these galaxies from the Spitzer Archive (http://sha.ipac.caltech.edu/applications/Spitzer/SHA/) and 8GHz images from the VLA archive (http://archive.nrao.edu/archive/archiveimage.html). We also selected a nearby AGN sub-sample containing 21 radio-selected AGNs for further spatial analysis. We selected 25 nearby AGNs exhibiting no detected radio emission in order to compare with the results of the radio-selected sources. For comparison, we also selected normal galaxies with distances less than 15Mpc from the catalog of Tully 1994 (see cat. VII/145). We only selected the galaxies that have Spitzer archive data and are not identified as AGNs in either the Veron-Cetty & Veron 2006 (see cat. VII/258) AGN catalog or in the NED database (http://ned.ipac.caltech.edu/). Our results for the radio-selected and the non-radio-selected active galaxies are listed in Table1, and those for the normal galaxies are listed in Table2. (2 data files).

Spitzer Instrument Pointing Frame (IPF) Kalman Filter Algorithm

NASA Technical Reports Server (NTRS)

Bayard, David S.; Kang, Bryan H.

2004-01-01

This paper discusses the Spitzer Instrument Pointing Frame (IPF) Kalman Filter algorithm. The IPF Kalman filter is a high-order square-root iterated linearized Kalman filter, which is parametrized for calibrating the Spitzer Space Telescope focal plane and aligning the science instrument arrays with respect to the telescope boresight. The most stringent calibration requirement specifies knowledge of certain instrument pointing frames to an accuracy of 0.1 arcseconds, per-axis, 1-sigma relative to the Telescope Pointing Frame. In order to achieve this level of accuracy, the filter carries 37 states to estimate desired parameters while also correcting for expected systematic errors due to: (1) optical distortions, (2) scanning mirror scale-factor and misalignment, (3) frame alignment variations due to thermomechanical distortion, and (4) gyro bias and bias-drift in all axes. The resulting estimated pointing frames and calibration parameters are essential for supporting on-board precision pointing capability, in addition to end-to-end 'pixels on the sky' ground pointing reconstruction efforts.

Blinded by the Light (Artist Concept)

NASA Technical Reports Server (NTRS)

2005-01-01

[figure removed for brevity, see original site] [figure removed for brevity, see original site] Figure 1: Visible PanelFigure 2: Infrared Panel

This artist's concept shows what a fiery hot star and its close-knit planetary companion might look close up if viewed in visible (figure 1) and infrared light (figure 2). In visible light, a star shines brilliantly, overwhelming the little light that is reflected by its planet. In infrared, a star is less blinding, and its planet perks up with a fiery glow.

Astronomers using NASA's Spitzer Space Telescope took advantage of this fact to directly capture the infrared light of two previously detected planets orbiting outside our solar system. Their findings revealed the temperatures and orbits of the planets. Upcoming Spitzer observations using a variety of infrared wavelengths may provide more information about the planets' winds and atmospheric compositions.

These colors represent real differences between the visible and infrared views of the system. The visible panel shows what our eyes would see if we could witness the system close up. The hot star is yellow because, like our Sun, it is brightest in yellow wavelengths. The warm planet, on the other hand, is brightest in infrared light, which we can't see. Instead, we would see the glimmer of star light that the planet reflects.

In the infrared panel, the colors reflect what our eyes might see if we could retune them to the invisible, infrared portion of the light spectrum. The hot star is less bright in infrared light than in visible and appears fainter. The warm planet peaks in infrared light, so is shown brighter. Their hues represent relative differences in temperature. Because the star is hotter than the planet, and because hotter objects give off more blue light than red, the star is depicted in blue, and the planet, red.

The overall look of the planet is inspired by theoretical models of hot, gas giant planets. These 'hot Jupiters' are similar to Jupiter in composition and mass, but are expected to look quite different at such high temperatures. The models are courtesy of Drs. Curtis Cooper and Adam Showman of the University of Arizona, Tucson.

X-ray Counterparts of Infrared Faint Radio Sources

NASA Astrophysics Data System (ADS)

Schartel, Norbert

2011-10-01

Infrared Faint Radio Sources (IFRS) are radio sources with extremely faint or even absent infrared emission in deep Spitzer Surveys. Models of their spectral energy distributions, the ratios of radio to infrared flux densities and their steep radio spectra strongly suggest that IFRS are AGN at high redshifts (2

Warm Spitzer and Palomar near-IR secondary eclipse photometry of two hot Jupiters: WASP-48b and HAT-P-23b

DOE Office of Scientific and Technical Information (OSTI.GOV)

O'Rourke, Joseph G.; Knutson, Heather A.; Désert, Jean-Michel

2014-02-01

We report secondary eclipse photometry of two hot Jupiters, WASP-48b and HAT-P-23b, at 3.6 and 4.5 μm taken with the InfraRed Array Camera aboard the Spitzer Space Telescope during the warm Spitzer mission and in the H and K{sub S} bands with the Wide Field IR Camera at the Palomar 200 inch Hale Telescope. WASP-48b and HAT-P-23b are Jupiter-mass and twice Jupiter-mass objects orbiting an old, slightly evolved F star and an early G dwarf star, respectively. In the H, K{sub S} , 3.6 μm, and 4.5 μm bands, respectively, we measure secondary eclipse depths of 0.047% ± 0.016%, 0.109%more » ± 0.027%, 0.176% ± 0.013%, and 0.214% ± 0.020% for WASP-48b. In the K{sub S} , 3.6 μm, and 4.5 μm bands, respectively, we measure secondary eclipse depths of 0.234% ± 0.046%, 0.248% ± 0.019%, and 0.309% ± 0.026% for HAT-P-23b. For WASP-48b and HAT-P-23b, respectively, we measure delays of 2.6 ± 3.9 minutes and 4.0 ± 2.4 minutes relative to the predicted times of secondary eclipse for circular orbits, placing 2σ upper limits on |ecos ω| of 0.0053 and 0.0080, both of which are consistent with circular orbits. The dayside emission spectra of these planets are well-described by blackbodies with effective temperatures of 2158 ± 100 K (WASP-48b) and 2154 ± 90 K (HAT-P-23b), corresponding to moderate recirculation in the zero albedo case. Our measured eclipse depths are also consistent with one-dimensional radiative transfer models featuring varying degrees of recirculation and weak thermal inversions or no inversions at all. We discuss how the absence of strong temperature inversions on these planets may be related to the activity levels and metallicities of their host stars.« less

Observation and Analysis of Secondary Eclipses of WASP-32b

NASA Astrophysics Data System (ADS)

Garland, Justin; Harrington, Joseph; Cubillos, Patricio E.; Blecic, Jasmina; Foster, Andrew S.; Bowman, Oliver; Maxted, Pierre F. L.

2015-11-01

We report two Spitzer secondary eclipses of the exoplanet WASP-32b. Discovered in 2010 by Maxted et al, this hot-Jupiter planet has a mass of 3.6 ± 0.07 Mj, a radius of 1.18 ± 0.07 Rj, an equilibrium temperature of 1560 ± 50 K, and an orbital period of 2.71865 ± 0.00008 days around a G-type star. We observed two secondary eclipses in the 3.6 µm and 4.5 µm channels using the Spitzer Space Telescope in 2010 as a part of the Spitzer Exoplanet Target of Opportunity program (program 60003). We present eclipse depth estimates of 0.0013 ± 0.00023 in the 4.5 µm band and inconclusive results in the 3.6 µm band. We also report an infrared brightness temperature of 1538 ± 110 in the 4.5 µm channel and refinements of orbital parameters for WASP-32b from our eclipse measurement as well as amatuer and professional data that closely match previous results. Spitzer is operated by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. This work was supported by NASA Planetary Atmospheres grant NNX12AI69G and NASA Astrophysics Data Analysis Program grant NNX13AF38G. JB holds a NASA Earth and Space Science Fellowship.

VizieR Online Data Catalog: Spitzer solar-type stars list (Meyer+, 2006)

NASA Astrophysics Data System (ADS)

Meyer, M. R.; Hillenbrand, L. A.; Backman, D.; Beckwith, S.; Bouwman, J.; Brooke, T.; Carpenter, J.; Cohen, M.; Cortes, S.; Crockett, N.; Gorti, U.; Henning, T.; Hines, D.; Hollenbach, D.; Kim, J. S.; Lunine, J.; Malhotra, R.; Mamajek, E.; Metchev, S.; Moro-Martin, A.; Morris, P.; Najita, J.; Padgett, D.; Pascucci, I.; Rodmann, J.; Schlingman, W.; Silverstone, M.; Soderblom, D.; Stauffer, J.; Stobie, E.; Strom, S.; Watson, D.; Weidenschilling, S.; Wolf, S.; Young, E.

2008-01-01

We provide an overview of the Spitzer Legacy Program, Formation and Evolution of Planetary Systems, that was proposed in 2000, begun in 2001, and executed aboard the Spitzer Space Telescope between 2003 and 2006. This program exploits the sensitivity of Spitzer to carry out mid-infrared spectrophotometric observations of solar-type stars. With a sample of 328 stars ranging in age from 3Myr to 3Gyr, we trace the evolution of circumstellar gas and dust from primordial planet-building stages in young circumstellar disks through to older collisionally generated debris disks. When completed, our program will help define the timescales over which terrestrial and gas giant planets are built, constrain the frequency of planetesimal collisions as a function of time, and establish the diversity of mature planetary architectures. In addition to the observational program, we have coordinated a concomitant theoretical effort aimed at understanding the dynamics of circumstellar dust with and without the effects of embedded planets, dust spectral energy distributions, and atomic and molecular gas line emission. Together with the observations, these efforts will provide an astronomical context for understanding whether our solar system and its habitable planets a common or a rare circumstance. Additional information about the FEPS project can be found on the team Web site. (4 data files).

The Formation and Evolution of Planetary Systems: Placing Our Solar System in Context with Spitzer

NASA Astrophysics Data System (ADS)

Meyer, Michael R.; Hillenbrand, Lynne A.; Backman, Dana; Beckwith, Steve; Bouwman, Jeroen; Brooke, Tim; Carpenter, John; Cohen, Martin; Cortes, Stephanie; Crockett, Nathan; Gorti, Uma; Henning, Thomas; Hines, Dean; Hollenbach, David; Kim, Jinyoung Serena; Lunine, Jonathan; Malhotra, Renu; Mamajek, Eric; Metchev, Stanimir; Moro-Martin, Amaya; Morris, Pat; Najita, Joan; Padgett, Deborah; Pascucci, Ilaria; Rodmann, Jens; Schlingman, Wayne; Silverstone, Murray; Soderblom, David; Stauffer, John; Stobie, Elizabeth; Strom, Steve; Watson, Dan; Weidenschilling, Stuart; Wolf, Sebastian; Young, Erick

2006-12-01

We provide an overview of the Spitzer Legacy Program, Formation and Evolution of Planetary Systems, that was proposed in 2000, begun in 2001, and executed aboard the Spitzer Space Telescope between 2003 and 2006. This program exploits the sensitivity of Spitzer to carry out mid-infrared spectrophotometric observations of solar-type stars. With a sample of ~328 stars ranging in age from ~3 Myr to ~3 Gyr, we trace the evolution of circumstellar gas and dust from primordial planet-building stages in young circumstellar disks through to older collisionally generated debris disks. When completed, our program will help define the timescales over which terrestrial and gas giant planets are built, constrain the frequency of planetesimal collisions as a function of time, and establish the diversity of mature planetary architectures. In addition to the observational program, we have coordinated a concomitant theoretical effort aimed at understanding the dynamics of circumstellar dust with and without the effects of embedded planets, dust spectral energy distributions, and atomic and molecular gas line emission. Together with the observations, these efforts will provide an astronomical context for understanding whether our solar system-and its habitable planet-is a common or a rare circumstance. Additional information about the FEPS project can be found on the team Web site.

Comparative Studies of the Dust around Red Supergiant and Oxygen-Rich Asymptotic Giant Branch Stars in the Local Universe

NASA Astrophysics Data System (ADS)

Sargent, B. A.; Srinivasan, S.; Speck, A.; Volk, K.; Kemper, F.; Reach, W.; Lagadec, E.; Bernard, J.-P.; McDonald, I.; Meixner, M.; Sloan, G. C.; Jones, O.

We analyze the dust emission features seen in Spitzer Space Telescope Infrared Spectrograph (IRS) spectra of red supergiant (RSG) and oxygen-rich asymptotic giant branch (AGB) stars in the Large Magellanic Cloud and Small Magellanic Cloud galaxies and in various Milky Way globular clusters. The spectra come from the Spitzer Legacy program SAGE-Spectroscopy (PI: F. Kemper), the Spitzer program SMC-Spec (PI: G. Sloan), and other archival Spitzer-IRS programs. The broad 10 and 20 micron emission features attributed to amorphous dust of silicate composition seen in the spectra show evidence for systematic differences in the centroid of both emission features between O-rich AGB and RSG populations. Radiative transfer modeling using the GRAMS grid of models of AGB and RSG stars suggests that the centroid differences are due to differences in dust properties. We investigate differences in dust composition, size, shape, etc that might be responsible for these spectral differences. We explore how these differences may arise from the different circumstellar environments around RSG and O-rich AGB stars and assess effects of varying metallicity (LMC versus SMC versus Milky Way globular cluster) and other properties (mass-loss rate, luminosity, etc.) on the dust originating from these stars. BAS acknowledges funding from NASA ADAP grant NNX13AD54G.

Secondary Eclipse Observations and Orbital Analysis of WASP-32b

NASA Astrophysics Data System (ADS)

Garland, Justin; Harrington, Joseph; Cubillos, Patricio; Blecic, Jasmina; Foster, Andrew S.; Bowman, Oliver; Maxted, Pierre F. L.

2016-01-01

We report two Spitzer secondary eclipses of the exoplanet WASP-32b. Discovered by Maxted et al. (2010), this hot-Jupiter planet has a mass of 3.6 ± 0.07 MJ a radius of 1.18 ± 0.07 RJ and an orbital period of 2.71865 ± 0.00008 days around a G-type star. We observed two secondary eclipses in the 3.6 μm and 4.5 μm channels using the Spitzer Space Telescope in 2010 as a part of the Spitzer Exoplanet Target of Opportunity program (program 60003). We present eclipse depth estimates of 0.0013 ± 0.00023 in the 4.5 μm band and inconclusive results in the 3.6 μm band. We also report an infrared brightness temperature of 1538 ± 110 in the 4.5 μm channel and refinements of orbital parameters for WASP-32b from our eclipse measurement as well as amatuer and professional data that closely match previous results. Spitzer is operated by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. This work was supported by NASA Planetary Atmospheres grant NNX12AI69G and NASA Astrophysics Data Analysis Program grant NNX13AF38G. JB holds a NASA Earth and Space Science Fellowship.

Are the infrared-faint radio sources pulsars?

NASA Astrophysics Data System (ADS)

Cameron, A. D.; Keith, M.; Hobbs, G.; Norris, R. P.; Mao, M. Y.; Middelberg, E.

2011-07-01

Infrared-faint radio sources (IFRS) are objects which are strong at radio wavelengths but undetected in sensitive Spitzer observations at infrared wavelengths. Their nature is uncertain and most have not yet been associated with any known astrophysical object. One possibility is that they are radio pulsars. To test this hypothesis we undertook observations of 16 of these sources with the Parkes Radio Telescope. Our results limit the radio emission to a pulsed flux density of less than 0.21 mJy (assuming a 50 per cent duty cycle). This is well below the flux density of the IFRS. We therefore conclude that these IFRS are not radio pulsars.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kobulnicky, Henry A.; Alexander, Michael J.; Babler, Brian L.

We characterize the completeness of point source lists from Spitzer Space Telescope surveys in the four Infrared Array Camera (IRAC) bandpasses, emphasizing the Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE) programs (GLIMPSE I, II, 3D, 360; Deep GLIMPSE) and their resulting point source Catalogs and Archives. The analysis separately addresses effects of incompleteness resulting from high diffuse background emission and incompleteness resulting from point source confusion (i.e., crowding). An artificial star addition and extraction analysis demonstrates that completeness is strongly dependent on local background brightness and structure, with high-surface-brightness regions suffering up to five magnitudes of reduced sensitivity to pointmore » sources. This effect is most pronounced at the IRAC 5.8 and 8.0 {mu}m bands where UV-excited polycyclic aromatic hydrocarbon emission produces bright, complex structures (photodissociation regions). With regard to diffuse background effects, we provide the completeness as a function of stellar magnitude and diffuse background level in graphical and tabular formats. These data are suitable for estimating completeness in the low-source-density limit in any of the four IRAC bands in GLIMPSE Catalogs and Archives and some other Spitzer IRAC programs that employ similar observational strategies and are processed by the GLIMPSE pipeline. By performing the same analysis on smoothed images we show that the point source incompleteness is primarily a consequence of structure in the diffuse background emission rather than photon noise. With regard to source confusion in the high-source-density regions of the Galactic Plane, we provide figures illustrating the 90% completeness levels as a function of point source density at each band. We caution that completeness of the GLIMPSE 360/Deep GLIMPSE Catalogs is suppressed relative to the corresponding Archives as a consequence of rejecting stars that lie in the point-spread function wings of saturated sources. This effect is minor in regions of low saturated star density, such as toward the Outer Galaxy; this effect is significant along sightlines having a high density of saturated sources, especially for Deep GLIMPSE and other programs observing closer to the Galactic center using 12 s or longer exposure times.« less

Cosmic Ornament of Gas and Dust

NASA Technical Reports Server (NTRS)

2007-01-01

[figure removed for brevity, see original site] 4-Panel Version Figure 1 [figure removed for brevity, see original site] [figure removed for brevity, see original site] [figure removed for brevity, see original site] Silicon Gas Figure 2 Argon Figure 3 Dust Collection Figure 4

This beautiful bulb might look like a Christmas ornament but it is the blown-out remains of a stellar explosion, or supernova. Called Cassiopeia A, this supernova remnant is located about 10,000 light-years away in our own Milky Way galaxy. The remains are shown here in an infrared composite from NASA's Spitzer Space Telescope. Silicon gas is blue and argon gas is green, while red represents about 10,000 Earth masses worth of dust. Yellow shows areas where red and green overlap.

The fact that these two features line up (as seen in yellow in the combined view) tells astronomers that the dust, together with the gas, was created in the explosion. This is the best evidence yet that supernovae are a significant source of dust in the early universe something that was postulated before, but not proven. Dust in our young universe is important because it eventually made its way into future stars, planets and even people.

In figure 1, the upper left panel is a composite made up of three infrared views shown in the remaining panels. The bottom left view (figure 3) shows argon gas (green) that was synthesized as it was ejected from the star. The upper right panel (figure 2) shows silicon gas (blue) deep in the interior of the remnant. This cooler gas, called the unshocked ejecta, was also synthesized in the supernova blast. The bottom right view (figure 4) shows a collection of dust (red), including proto-silicates, silicate dioxide and iron oxide.

The data for these images were taken by Spitzer's infrared spectrograph, which splits light apart to reveal the fingerprints of molecules and elements. In total, Spitzer collected separate 'spectra' at more than 1,700 positions across Cassiopeia A. Astronomers then created maps from this massive grid of data, showing the remnant in a multitude of infrared colors.

Mid-Infrared Properties of OH Megamaser Host Galaxies. I. Spitzer IRS Low- and High-Resolution Spectroscopy

NASA Astrophysics Data System (ADS)

Willett, Kyle W.; Darling, Jeremy; Spoon, Henrik W. W.; Charmandaris, Vassilis; Armus, Lee

2011-03-01

We present mid-infrared spectra and photometry from the Infrared Spectrograph on the Spitzer Space Telescope for 51 OH megamasers (OHMs), along with 15 galaxies confirmed to have no megamaser emission above L OH = 102.3 L sun. The majority of galaxies display moderate-to-deep 9.7 μm amorphous silicate absorption, with OHM galaxies showing stronger average absorption and steeper 20-30 μm continuum emission than non-masing galaxies. Emission from multiple polycyclic aromatic hydrocarbons (PAHs), especially at 6.2, 7.7, and 11.3 μm, is detected in almost all systems. Fine-structure atomic emission (including [Ne II], [Ne III], [S III], and [S IV]) and multiple H2 rotational transitions are observed in more than 90% of the sample. A subset of galaxies show emission from rarer atomic lines, such as [Ne V], [O IV], and [Fe II]. Fifty percent of the OHMs show absorption from water ice and hydrogenated amorphous carbon grains, while absorption features from CO2, HCN, C2H2, and crystalline silicates are also seen in several OHMs. Column densities of OH derived from 34.6 μm OH absorption are similar to those derived from 1667 MHz OH absorption in non-masing galaxies, indicating that the abundance of masing molecules is similar for both samples. This data paper presents full mid-infrared spectra for each galaxy, along with measurements of line fluxes and equivalent widths, absorption feature depths, and spectral indices.

The UK Infrared Telescope M33 monitoring project - IV. Variable red giant stars across the galactic disc

NASA Astrophysics Data System (ADS)

Javadi, Atefeh; Saberi, Maryam; van Loon, Jacco Th.; Khosroshahi, Habib; Golabatooni, Najmeh; Mirtorabi, Mohammad Taghi

2015-03-01

We have conducted a near-infrared monitoring campaign at the UK InfraRed Telescope, of the Local Group spiral galaxy M33 (Triangulum). The main aim was to identify stars in the very final stage of their evolution, and for which the luminosity is more directly related to the birth mass than the more numerous less-evolved giant stars that continue to increase in luminosity. In this fourth paper of the series, we present a search for variable red giant stars in an almost square degree region comprising most of the galaxy's disc, carried out with the WFCAM (Wide Field CAMera) instrument in the K band. These data, taken during the period 2005-2007, were complemented by J- and H-band images. Photometry was obtained for 403 734 stars in this region; of these, 4643 stars were found to be variable, most of which are asymptotic giant branch (AGB) stars. The variable stars are concentrated towards the centre of M33, more so than low-mass, less-evolved red giants. Our data were matched to optical catalogues of variable stars and carbon stars and to mid-infrared photometry from the Spitzer Space Telescope. Most dusty AGB stars had not been previously identified in optical variability surveys, and our survey is also more complete for these types of stars than the Spitzer survey. The photometric catalogue is made publicly available at the Centre de Données astronomiques de Strasbourg.

9500 Nights of Mid-Infrared Observations of SN 1987A: the birth of the remnant

NASA Astrophysics Data System (ADS)

Bouchet, Patrice; Danziger, John

2014-01-01

The one-in-a-life-time event Supernova SN 1987A, the brightest supernova seen since Kepler's in 1604, has given us a unique opportunity to study the mechanics of a supernova explosion and now to witness the birth of a supernova remnant. A violent encounter is underway between the fastest-moving debris and the circumstellar ring: shocks excite ``hotspots''. ATCA/ANTF, Gemini, VLT, HST, Spitzer, Chandra, and recently ALMA observations have been so far organized to help understanding the several emission mechanisms at work. In the mid-infrared SN 1987A has transformed from a SN with the bulk of its radiation from the ejecta to a SNR whose emission is dominated by the interaction of the blast wave with the surrounding interstellar medium, a process in which kinetic energy is converted into radiative energy. Currently this remnant emission is dominated by material in or near the inner equatorial ring (ER). We give here a brief history of our mid-infrared observations, and present our last data obtained with the SPITZER infrared satellite and the ESO VLT and Gemini telescopes: we show how together with Chandra observations, they contribute to the understanding of this fascinating object. We argue also that our imaging observations suggest that warm dust is still present in the ejecta, and we dispute the presence of huge amount of very cold dust in it, as it has been claimed on the basis of data obtained with the HERSCHELl satellite.

The UK Infrared Telescope M33 monitoring project - I. Variable red giant stars in the central square kiloparsec

NASA Astrophysics Data System (ADS)

Javadi, Atefeh; van Loon, Jacco Th.; Mirtorabi, Mohammad Taghi

2011-02-01

We have conducted a near-infrared monitoring campaign at the UK Infrared Telescope (UKIRT), of the Local Group spiral galaxy M33 (Triangulum). The main aim was to identify stars in the very final stage of their evolution, and for which the luminosity is more directly related to the birth mass than the more numerous less-evolved giant stars that continue to increase in luminosity. The most extensive data set was obtained in the K band with the UIST instrument for the central 4 × 4 arcmin2 (1 kpc2) - this contains the nuclear star cluster and inner disc. These data, taken during the period 2003-2007, were complemented by J- and H-band images. Photometry was obtained for 18 398 stars in this region; of these, 812 stars were found to be variable, most of which are asymptotic giant branch (AGB) stars. Our data were matched to optical catalogues of variable stars and carbon stars and to mid-infrared photometry from the Spitzer Space Telescope. In this first of a series of papers, we present the methodology of the variability survey and the photometric catalogue - which is made publicly available at the Centre de Données astronomiques de Strasbourg - and discuss the properties of the variable stars. The most dusty AGB stars had not been previously identified in optical variability surveys, and our survey is also more complete for these types of stars than the Spitzer survey.

The Great Observatories All-Sky LIRG Survey: Herschel Image Atlas and Aperture Photometry

NASA Astrophysics Data System (ADS)

Chu, Jason K.; Sanders, D. B.; Larson, K. L.; Mazzarella, J. M.; Howell, J. H.; Díaz-Santos, T.; Xu, K. C.; Paladini, R.; Schulz, B.; Shupe, D.; Appleton, P.; Armus, L.; Billot, N.; Chan, B. H. P.; Evans, A. S.; Fadda, D.; Frayer, D. T.; Haan, S.; Ishida, C. M.; Iwasawa, K.; Kim, D.-C.; Lord, S.; Murphy, E.; Petric, A.; Privon, G. C.; Surace, J. A.; Treister, E.

2017-04-01

Far-infrared images and photometry are presented for 201 Luminous and Ultraluminous Infrared Galaxies [LIRGs: log ({L}{IR}/{L}⊙ )=11.00{--}11.99, ULIRGs: log ({L}{IR}/{L}⊙ )=12.00{--}12.99], in the Great Observatories All-Sky LIRG Survey (GOALS), based on observations with the Herschel Space Observatory Photodetector Array Camera and Spectrometer (PACS) and the Spectral and Photometric Imaging Receiver (SPIRE) instruments. The image atlas displays each GOALS target in the three PACS bands (70, 100, and 160 μm) and the three SPIRE bands (250, 350, and 500 μm), optimized to reveal structures at both high and low surface brightness levels, with images scaled to simplify comparison of structures in the same physical areas of ˜100 × 100 kpc2. Flux densities of companion galaxies in merging systems are provided where possible, depending on their angular separation and the spatial resolution in each passband, along with integrated system fluxes (sum of components). This data set constitutes the imaging and photometric component of the GOALS Herschel OT1 observing program, and is complementary to atlases presented for the Hubble Space Telescope, Spitzer Space Telescope, and Chandra X-ray Observatory. Collectively, these data will enable a wide range of detailed studies of active galactic nucleus and starburst activity within the most luminous infrared galaxies in the local universe. Based on Herschel Space Observatory observations. Herschel is an ESA space observatory with science instruments provided by the European-led Principal Investigator consortia, and important participation from NASA.

Strengthening the Connection Between Space and Society: A Comparative Analysis of Supernovae Distribution in the Andromeda Galaxy for Secondary School Students

NASA Astrophysics Data System (ADS)

Borders, Kareen; Mendez, B.; Borders, K.; Thaller, M.; Plecki, M.; Usuda, K.

2011-05-01

In order to prepare students in grades 4-12 for a global workforce, NASA supports science, technology, engineering, and math (STEM) immersion education for secondary students. Secondary schools, through the NASA Explorer School program, the Spitzer Space Telescope, the National Optical Astronomy Observatory, and the WISE (Wide Field Infrared Survey Explorer) Telescope Teacher Ambassador program, offer authentic research opportunities for students. Spitzer and WISE studied the sky in infrared light. Among the objects WISE studied are asteroids, the coolest and dimmest stars, and the most luminous galaxies. The lessons learned from the NASA Explorer School program and Spitzer and WISE teacher and student programs can be applied to other programs, engaging students in authentic research experiences by using data from space-borne and earth-based observatories such Kitt Peak Observatory. Several ground based telescopes at Kitt Peak Observatory study visible light from objects such as supernovae. Utilizing a student research immersion philosophy along with data analysis skills learned from the Spitzer and WISE student research programs, an analysis of supernovae distribution with respect to location in the Andromeda galaxy was conducted using images of the Andromeda galaxy taken from the WIYN 0.9 meter telescope on Kitt Peak. A comparison was made between the 12 outer fields (spiral arms) and the 4 inner fields (central bulge). Novae were found by "blinking” images of each field throughout 100 epochs of data. Blinking is a technique used to compare images of fields and noting brightness (via x,y coordinates) in one field that is not visible in the same field during a different epoch. Although the central bulge was expected to contain more supernovae due to stellar density and proximity of stars to each other, analysis of data indicates that the there is also a concentration of supernovae that appeared in outer regions. WISE Telescope funding is gratefully acknowledged.

Super-Comet or Big Asteroid Belt?

NASA Technical Reports Server (NTRS)

2005-01-01

[figure removed for brevity, see original site] Figure 1: Spectrograph of HD 69830

This graph of data from NASA's Spitzer Space Telescope demonstrates that the dust around a nearby star called HD 69830 (upper line) has a very similar composition to that of Comet Hale-Bopp. Spitzer spotted large amounts of this dust in the inner portion of the HD 69830 system.

The bumps and dips seen in these data, or spectra, represent the 'fingerprints' of various minerals. Spectra are created when an instrument called a spectrograph spreads light out into its basic parts, like a prism turning sunlight into a rainbow. These particular spectra reveal the presence of the silicate mineral called olivine, and more specifically, a type of olivine called forsterite, which is pictured in the inset box. Forsterite is a bright-green gem found on Earth, on the 'Green Sand Beach' of Hawaii among other places; and in space, in comets and asteroids.

Because the dust around HD 69830 has a very similar make-up to that of Comet Hale-Bopp, astronomers speculate that it might be coming from a giant comet nearly the size of Pluto. Such a comet may have been knocked into the inner solar system of HD 69830, where it is now leaving in its wake a trail of evaporated dust.

Nonetheless, astronomers say the odds that Spitzer has caught a 'super-comet' spiraling in toward its star - an unusual and relatively short-lived event - are slim. Instead, they favor the theory that the observed dust is actually the result of asteroids banging together in a massive asteroid belt.

The data of HD 69830's dust were taken by Spitzer's infrared spectrograph. The data of Comet Hale-Bopp were taken by the European Space Agency's Infrared Observatory Satellite. The picture of forsterite comes courtesy of Dr. George Rossman, California Institute of Technology, Pasadena.

Featured Image: A Detailed Look at the Crab Nebula

NASA Astrophysics Data System (ADS)

Kohler, Susanna

2017-07-01

Planning on watching fireworks tomorrow? Heres an astronomical firework to help you start the celebrations! A new study has stunningly detailed the Crab Nebula (click for a closer look), a nebula 6,500 light-years away thought to have been formedby a supernova explosion and the subsequent ultrarelativistic wind emitted by the pulsar at its heart. Led by Gloria Dubner (University of Buenos Aires), the authors of this study obtained new observations of the Crab Nebula from five different telescopes. They compiled these observations to compare the details of the nebulas structure across different wavelengths, which allowedthem to learnabout the sources of various features within the nebula. In the images above, thetop left shows the 3 GHz data from the Very Large Array (radio). Moving clockise, the radio data (shown in red) is composited with: infrared data from Spitzer Space Telescope, optical continuum from Hubble Space Telescope, 500-nm optical datafrom Hubble, and ultraviolet data from XMM-Newton. The final two images are of the nebula center, and they are composites of the radio imagewith X-ray data from Chandra and near-infrared data from Hubble. To read more about what Dubner and collaborators learned (and to see more spectacular images!), check out the paper below.CitationG. Dubner et al 2017 ApJ 840 82. doi:10.3847/1538-4357/aa6983

NASA Tech Briefs, January 2007

NASA Technical Reports Server (NTRS)

2007-01-01

Topics covered include: Flexible Skins Containing Integrated Sensors and Circuitry; Artificial Hair Cells for Sensing Flows; Video Guidance Sensor and Time-of-Flight Rangefinder; Optical Beam-Shear Sensors; Multiple-Agent Air/Ground Autonomous Exploration Systems; A 640 512-Pixel Portable Long-Wavelength Infrared Camera; An Array of Optical Receivers for Deep-Space Communications; Microstrip Antenna Arrays on Multilayer LCP Substrates; Applications for Subvocal Speech; Multiloop Rapid-Rise/Rapid Fall High-Voltage Power Supply; The PICWidget; Fusing Symbolic and Numerical Diagnostic Computations; Probabilistic Reasoning for Robustness in Automated Planning; Short-Term Forecasting of Radiation Belt and Ring Current; JMS Proxy and C/C++ Client SDK; XML Flight/Ground Data Dictionary Management; Cross-Compiler for Modeling Space-Flight Systems; Composite Elastic Skins for Shape-Changing Structures; Glass/Ceramic Composites for Sealing Solid Oxide Fuel Cells; Aligning Optical Fibers by Means of Actuated MEMS Wedges; Manufacturing Large Membrane Mirrors at Low Cost; Double-Vacuum-Bag Process for Making Resin- Matrix Composites; Surface Bacterial-Spore Assay Using Tb3+/DPA Luminescence; Simplified Microarray Technique for Identifying mRNA in Rare Samples; High-Resolution, Wide-Field-of-View Scanning Telescope; Multispectral Imager With Improved Filter Wheel and Optics; Integral Radiator and Storage Tank; Compensation for Phase Anisotropy of a Metal Reflector; Optical Characterization of Molecular Contaminant Films; Integrated Hardware and Software for No-Loss Computing; Decision-Tree Formulation With Order-1 Lateral Execution; GIS Methodology for Planning Planetary-Rover Operations; Optimal Calibration of the Spitzer Space Telescope; Automated Detection of Events of Scientific Interest; Representation-Independent Iteration of Sparse Data Arrays; Mission Operations of the Mars Exploration Rovers; and More About Software for No-Loss Computing.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steele, Amy; Hughes, A. Meredith; Carpenter, John

The presence of debris disks around young main-sequence stars hints at the existence and structure of planetary systems. Millimeter-wavelength observations probe large grains that trace the location of planetesimal belts. The Formation and Evolution of Planetary Systems Spitzer Legacy survey of nearby young solar analogues yielded a sample of five debris disk-hosting stars with millimeter flux suitable for interferometric follow-up. We present observations with the Submillimeter Array (SMA) and the Combined Array for Research in Millimeter-wave Astronomy at ∼2″ resolution that spatially resolve the debris disks around these nearby (d ∼ 50 pc) stars. Two of the five disks (HDmore » 377, HD 8907) are spatially resolved for the first time and one (HD 104860) is resolved at millimeter wavelengths for the first time. We combine our new observations with archival SMA and Atacama Large Millimeter/Submillimeter Array data to enable a uniform analysis of the full five-object sample. We simultaneously model the broadband photometric data and resolved millimeter visibilities to constrain the dust temperatures and disk morphologies, and perform a Markov Chain Monte Carlo analysis to fit for basic structural parameters. We find that the radii and widths of the cold outer belts exhibit properties consistent with scaled-up versions of the Solar System's Kuiper Belt. All the disks exhibit characteristic grain sizes comparable to the blowout size, and all the resolved observations of emission from large dust grains are consistent with an axisymmetric dust distribution to within the uncertainties. These results are consistent with comparable studies carried out at infrared wavelengths.« less

WIRED for EC: New White Dwarfs with WISE Infrared Excesses and New Classification Schemes from the Edinburgh–Cape Blue Object Survey

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dennihy, E.; Clemens, J. C.; Dunlap, B. H.

We present a simple method for identifying candidate white dwarf systems with dusty exoplanetary debris based on a single temperature blackbody model fit to the infrared excess. We apply this technique to a sample of Southern Hemisphere white dwarfs from the recently completed Edinburgh–Cape Blue Object Survey and identify four new promising dusty debris disk candidates. We demonstrate the efficacy of our selection method by recovering three of the four Spitzer confirmed dusty debris disk systems in our sample. Further investigation using archival high-resolution imaging shows that Spitzer data of the unrecovered fourth object is likely contaminated by a line-of-sightmore » object that either led to a misclassification as a dusty disk in the literature or is confounding our method. Finally, in our diagnostic plot, we show that dusty white dwarfs, which also host gaseous debris, lie along a boundary of our dusty debris disk region, providing clues to the origin and evolution of these especially interesting systems.« less

A TREND BETWEEN COLD DEBRIS DISK TEMPERATURE AND STELLAR TYPE: IMPLICATIONS FOR THE FORMATION AND EVOLUTION OF WIDE-ORBIT PLANETS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ballering, Nicholas P.; Rieke, George H.; Su, Kate Y. L.

2013-09-20

Cold debris disks trace the limits of planet formation or migration in the outer regions of planetary systems, and thus have the potential to answer many of the outstanding questions in wide-orbit planet formation and evolution. We characterized the infrared excess spectral energy distributions of 174 cold debris disks around 546 main-sequence stars observed by both the Spitzer Infrared Spectrograph and the Multiband Imaging Photometer for Spitzer. We found a trend between the temperature of the inner edges of cold debris disks and the stellar type of the stars they orbit. This argues against the importance of strictly temperature-dependent processesmore » (e.g., non-water ice lines) in setting the dimensions of cold debris disks. Also, we found no evidence that delayed stirring causes the trend. The trend may result from outward planet migration that traces the extent of the primordial protoplanetary disk, or it may result from planet formation that halts at an orbital radius limited by the efficiency of core accretion.« less

Asteroid 'Bites the Dust' Around Dead Star

NASA Technical Reports Server (NTRS)

2009-01-01

NASA's Spitzer Space Telescope set its infrared eyes upon the dusty remains of shredded asteroids around several dead stars. This artist's concept illustrates one such dead star, or 'white dwarf,' surrounded by the bits and pieces of a disintegrating asteroid. These observations help astronomers better understand what rocky planets are made of around other stars.

Asteroids are leftover scraps of planetary material. They form early on in a star's history when planets are forming out of collisions between rocky bodies. When a star like our sun dies, shrinking down to a skeleton of its former self called a white dwarf, its asteroids get jostled about. If one of these asteroids gets too close to the white dwarf, the white dwarf's gravity will chew the asteroid up, leaving a cloud of dust.

Spitzer's infrared detectors can see these dusty clouds and their various constituents. So far, the telescope has identified silicate minerals in the clouds polluting eight white dwarfs. Because silicates are common in our Earth's crust, the results suggest that planets similar to ours might be common around other stars.

Black Widow Nebula Hiding in the Dust

NASA Technical Reports Server (NTRS)

2005-01-01

In this Spitzer image, the two opposing bubbles are being formed in opposite directions by the powerful outflows from massive groups of forming stars. The baby stars can be seen as specks of yellow where the two bubbles overlap.

When individual stars form from molecular clouds of gas and dust they produce intense radiation and very strong particle winds. Both the radiation and the stellar winds blow the dust outward from the star creating a cavity or, bubble.

In the case of the Black Widow Nebula, astronomers suspect that a large cloud of gas and dust condensed to create multiple clusters of massive star formation. The combined winds from these groups of large stars probably blew out bubbles into the direction of least resistance, forming a double bubble.

The infrared image was captured by the Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE) Legacy project. The Spitzer picture is a four-channel false-color composite, showing emission from wavelengths of 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange) and 8.0 microns (red).

What Feeds the Beast in a Galaxy Cluster?

NASA Image and Video Library

2015-09-10

A massive cluster of galaxies, called SpARCS1049+56, can be seen in this multi-wavelength view from NASA Hubble and Spitzer space telescopes. At the middle of the picture is the largest, central member of the family of galaxies (upper right red dot of central pair). Unlike other central galaxies in clusters, this one is bursting with the birth of new stars. Scientists say this star birth was triggered by a collision between a smaller galaxy and the giant, central galaxy. The smaller galaxy's wispy, shredded parts, called a tidal tail, can be seen coming out below the larger galaxy. Throughout this region are features called "beads on a string," which are areas where gas has clumped to form new stars. This type of "feeding" mechanism for galaxy clusters -- where gas from the merging of galaxies is converted to new stars -- is rare. The Hubble data in this image show infrared light with a wavelength of 1 micron in blue, and 1.6 microns in green. The Spitzer data show infrared light of 3.6 microns in red. http://photojournal.jpl.nasa.gov/catalog/PIA19837

Multi-wavelength Morphological Study Of Star Forming Regions In Nearby Cluster-rich Lirgs

NASA Astrophysics Data System (ADS)

Vavilkin, Tatjana; Evans, A.; Mazzarella, J.; Surace, J.; Kim, D.; Howell, J.; Armus, L.; GOALS Team

2009-05-01

Luminous Infrared Galaxies (LIRGs) are believed to play an important role in star formation history of the universe. Many LIRGs undergo intense bursts of star formation as a result of interaction/merger process. Given the dusty nature of LIRGs, it is necessary to probe Luminous Infrared Galaxies at multiple wavelengths. The Great Observatories All-sky LIRG Survey (GOALS) combines data from NASA's Spitzer, Hubble, Chandra and GALEX observatories and offers a unique opportunity to gain insights into the physical processes in these highly dust enshrouded systems. We examine a sample of 11 nearby (z < 0.03) cluster-rich (> 200 clusters as seen in HST ACS images) LIRG systems at various interaction stages. The combined HST ACS optical imaging, Spitzer IRAC 8 micron channel and GALEX near-UV imaging allows us to access the properties of visible and obscured star forming regions. We study the spatial distribution of star forming regions at these wavelengths, correlate locations of young stellar clusters with PAH and UV emission regions and trace changes with merger stage.

Cool Star Beginnings: YSOs in the Perseus Molecular Cloud

NASA Astrophysics Data System (ADS)

Young, Kaisa E.; Young, Chadwick H.

2015-01-01

Nearby molecular clouds, where there is considerable evidence of ongoing star formation, provide the best opportunity to observe stars in the earliest stages of their formation. The Perseus molecular cloud contains two young clusters, IC 348 and NGC 1333 and several small dense cores of the type that produce only a few stars. Perseus is often cited as an intermediate case between quiescent low-mass and turbulent high-mass clouds, making it perhaps an ideal environment for studying ``typical low-mass star formation. We present an infrared study of the Perseus molecular cloud with data from the Spitzer Space Telescope as part of the ``From Molecular Cores to Planet Forming Disks (c2d) Legacy project tep{eva03}. By comparing Spitzer's near- and mid-infrared maps, we identify and classify the young stellar objects (YSOs) in the cloud using updated extinction corrected photometry. Virtually all of the YSOs in Perseus are forming in the clusters and other smaller associations at the east and west ends of the cloud with very little evidence of star formation in the midsection even in areas of high extinction.

CROSS-CORRELATION BETWEEN X-RAY AND OPTICAL/NEAR-INFRARED BACKGROUND INTENSITY FLUCTUATIONS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mitchell-Wynne, Ketron; Cooray, Asantha; Xue, Yongquan

Angular power spectra of optical and infrared background anisotropies at wavelengths between 0.5 and 5 μ m are a useful probe of faint sources present during reionization, in addition to faint galaxies and diffuse signals at low redshift. The cross-correlation of these fluctuations with backgrounds at other wavelengths can be used to separate some of these signals. A previous study on the cross-correlation between X-ray and Spitzer fluctuations at 3.6 μ m and 4.5 μ m has been interpreted as evidence for direct collapse black holes present at z  > 12. Here we return to this cross-correlation and study its wavelengthmore » dependence from 0.5 to 4.5 μ m using Hubble and Spitzer data in combination with a subset of the 4 Ms Chandra observations in GOODS-S/ECDFS. Our study involves five Hubble bands at 0.6, 0.7, 0.85, 1.25, and 1.6 μ m, and two Spitzer -IRAC bands at 3.6 μ m and 4.5 μ m. We confirm the previously seen cross-correlation between 3.6 μ m (4.5 μ m) and X-rays with 3.7 σ (4.2 σ ) and 2.7 σ (3.7 σ ) detections in the soft [0.5–2] keV and hard [2–8] keV X-ray bands, respectively, at angular scales above 20 arcsec. The cross-correlation of X-rays with Hubble is largely anticorrelated, ranging between the levels of 1.4 σ –3.5 σ for all the Hubble and X-ray bands. This lack of correlation in the shorter optical/NIR bands implies the sources responsible for the cosmic infrared background at 3.6 and 4.5 μ m are at least partly dissimilar to those at 1.6 μ m and shorter.« less

RR Lyrae period luminosity relations with Spitzer

NASA Astrophysics Data System (ADS)

Neeley, Jillian R.; Marengo, Massimo; CRRP Team

2017-01-01

RR Lyrae variable stars have long been known to be valuable distance indicators, but only recently has a well defined period luminosity relationship been utilized at infrared wavelengths. In my thesis, I am combining Spitzer Space Telescope data of RR Lyrae stars obtained as part of the Carnegie RR Lyrae Program with ground based NIR data to characterize the period-luminosity-metallicity (PLZ) relation and provide an independent Population II calibration of the cosmic distance scale. I will discuss the ongoing efforts to calibrate this relation using objects such as M4 and NGC 6441 and how the first data release from the Gaia mission impacts our findings. I will also compare my preliminary empirical relations to theoretical PLZ relations derived from stellar pulsation models.

Spitzer Observations of the X-ray Sources of NGC 4485/90

NASA Astrophysics Data System (ADS)

Vazquez, Gerardo A.; Colbert, E.; Hornschemeier, A.; Malhotra, S.; Roberts, T.; Ward, M.

2006-06-01

The mechanism for forming (or igniting) so-called Ultra-Luminous X- ray sources (ULXs) is very poorly understood. In order to investigate the stellar and gaseous environment of ULXs, we have observed the nearby starburst galaxy system NGC 4485/90 with Spitzer's IRAC and IRS instruments. High-quality mid-infrared images and spectra are used to characterize the stellar history of stars near the ULXs, and the ionization state of the surrounding gas. NGC 4485/90 fortuitively hosts six ULXs, and we have analyzed IRAC images and IRS spectra of all six regions. We also observed two "comparison" regions with no X-ray sources. Here we present our preliminary findings on the similarities and differences between the stellar and gaseous components near the ULXs.

FIR/THz Space Interferometry: Science Opportunities, Mission Concepts, and Technical Challenges

NASA Technical Reports Server (NTRS)

Leisawitz, David

2007-01-01

Sensitive far-IR imaging and spectroscopic measurements of astronomical objects on sub-arcsecond angular scales are essential to our understanding of star and planet formation, the formation and evolution of galaxies, and to the detection and characterization of extrasolar planets. Cold single-aperture telescopes in space, such as the Spitzer Space Telescope and the Herschel Space Observatory, are very sensitive, but they lack the necessary angular resolution by two or more orders of magnitude. Far-IR space interferometers will address this need in the coming decades. Several mission concepts have already been studied, including in the US the Space Infrared Interferometric Telescope (SPIRIT) and the more ambitious Submillimeter Probe of the Evolution of Cosmic Structure (SPECS). This talk will describe science goals and summarize alternative concepts for future FIR/THz space interferometry missions. Small arrays of sensitive, fast, direct detectors are a key enabling technology for SPIRIT and SPECS. I will describe the technology requirements for far-IR interferometry, including the detector requirements, and their derivation from the mission science goals and instrument concepts.

Cassiopeia A supernova

NASA Image and Video Library

2017-12-08

NASA's Fermi Closes on Source of Cosmic Rays New images from NASA's Fermi Gamma-ray Space Telescope show where supernova remnants emit radiation a billion times more energetic than visible light. The images bring astronomers a step closer to understanding the source of some of the universe's most energetic particles -- cosmic rays. This composite shows the Cassiopeia A supernova remnant across the spectrum: Gamma rays (magenta) from NASA's Fermi Gamma-ray Space Telescope; X-rays (blue, green) from NASA's Chandra X-ray Observatory; visible light (yellow) from the Hubble Space Telescope; infrared (red) from NASA's Spitzer Space Telescope; and radio (orange) from the Very Large Array near Socorro, N.M. Credit: NASA/DOE/Fermi LAT Collaboration, CXC/SAO/JPL-Caltech/Steward/O. Krause et al., and NRAO/AUI For more information: www.nasa.gov/mission_pages/GLAST/news/cosmic-rays-source.... NASA Goddard Space Flight Center is home to the nation's largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe. Follow us on Twitter Join us on Facebook

A Natal Microcosm

NASA Technical Reports Server (NTRS)

2004-01-01

In the quest to better understand the birth of stars and the formation of new worlds, astronomers have used NASA's Spitzer Space Telescope to examine the massive stars contained in a cloudy region called Sharpless 140. This cloud is a fascinating microcosm of a star-forming region since it exhibits, within a relatively small area, all of the classic manifestations of stellar birth.

Sharpless 140 lies almost 3000 light-years from Earth in the constellation Cepheus. At its heart is a cluster of three deeply embedded young stars, which are each several thousand times brighter than the Sun. Though they are strikingly visible in this image from Spitzer's infrared array camera, they are completely obscured in visible light, buried within the core of the surrounding dust cloud.

The extreme youth of at least one of these stars is indicated by the presence of a stream of gas moving at high velocities. Such outflows are signatures of the processes surrounding a star that is still gobbling up material as part of its formation.

The bright red bowl, or arc, seen in this image traces the outer surface of the dense dust cloud encasing the young stars. This arc is made up primarily of organic compounds called polycyclic aromatic hydrocarbons, which glow on the surface of the cloud. Ultraviolet light from a nearby bright star outside of the image is 'eating away' at these molecules. Eventually, this light will destroy the dust envelope and the masked young stars will emerge.

This false-color image was taken on Oct. 11, 2003 and is composed of photographs obtained at four wavelengths: 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange) and 8 microns (red).

A Natal Microcosm

NASA Image and Video Library

2004-05-11

In the quest to better understand the birth of stars and the formation of new worlds, astronomers have used NASA's Spitzer Space Telescope to examine the massive stars contained in a cloudy region called Sharpless 140. This cloud is a fascinating microcosm of a star-forming region since it exhibits, within a relatively small area, all of the classic manifestations of stellar birth. Sharpless 140 lies almost 3000 light-years from Earth in the constellation Cepheus. At its heart is a cluster of three deeply embedded young stars, which are each several thousand times brighter than the Sun. Though they are strikingly visible in this image from Spitzer's infrared array camera, they are completely obscured in visible light, buried within the core of the surrounding dust cloud. The extreme youth of at least one of these stars is indicated by the presence of a stream of gas moving at high velocities. Such outflows are signatures of the processes surrounding a star that is still gobbling up material as part of its formation. The bright red bowl, or arc, seen in this image traces the outer surface of the dense dust cloud encasing the young stars. This arc is made up primarily of organic compounds called polycyclic aromatic hydrocarbons, which glow on the surface of the cloud. Ultraviolet light from a nearby bright star outside of the image is "eating away" at these molecules. Eventually, this light will destroy the dust envelope and the masked young stars will emerge. This false-color image was taken on Oct. 11, 2003 and is composed of photographs obtained at four wavelengths: 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange) and 8 microns (red). http://photojournal.jpl.nasa.gov/catalog/PIA05878

H‑ Opacity and Water Dissociation in the Dayside Atmosphere of the Very Hot Gas Giant WASP-18b

NASA Astrophysics Data System (ADS)

Arcangeli, Jacob; Désert, Jean-Michel; Line, Michael R.; Bean, Jacob L.; Parmentier, Vivien; Stevenson, Kevin B.; Kreidberg, Laura; Fortney, Jonathan J.; Mansfield, Megan; Showman, Adam P.

2018-03-01

We present one of the most precise emission spectra of an exoplanet observed so far. We combine five secondary eclipses of the hot Jupiter WASP-18b (T day ∼ 2900 K) that we secured between 1.1 and 1.7 μm with the Wide Field Camera 3 instrument on board the Hubble Space Telescope. Our extracted spectrum (S/N = 50, R ∼ 40) does not exhibit clearly identifiable molecular features but is poorly matched by a blackbody spectrum. We complement this data with previously published Spitzer/Infrared Array Camera observations of this target and interpret the combined spectrum by computing a grid of self-consistent, 1D forward models, varying the composition and energy budget. At these high temperatures, we find there are important contributions to the overall opacity from H‑ ions, as well as the removal of major molecules by thermal dissociation (including water), and thermal ionization of metals. These effects were omitted in previous spectral retrievals for very hot gas giants, and we argue that they must be included to properly interpret the spectra of these objects. We infer a new metallicity and C/O ratio for WASP-18b, and find them well constrained to be solar ([M/H] = ‑0.01 ± 0.35, C/O < 0.85 at 3σ confidence level), unlike previous work but in line with expectations for giant planets. The best-fitting self-consistent temperature–pressure profiles are inverted, resulting in an emission feature at 4.5 μm seen in the Spitzer photometry. These results further strengthen the evidence that the family of very hot gas giant exoplanets commonly exhibit thermal inversions.

Deciphering IR Excess Observed by the Spitzer Space Telescope in Short Period Interacting Cataclysmic Binaries

NASA Astrophysics Data System (ADS)

Chun, Howard; Brinkworth, Carolyn; Ciardi, David; Hoard, Don; Howell, Steve; Stefaniak, Linda; Thomas, Beth

2006-03-01

During the first year of the Spitzer Space Telescope Observing Program for Students and Teachers, our team observed a small sample of short orbital period interacting white dwarf binaries. Our scientific investigation was aimed at detection and characterization of the low mass, cool, brown dwarf-like mass donors in these systems. We used the Infrared Array Camera to obtain photometric observations of the polars EF Eri, GG Leo, V347 Pav, and RX J0154.0-5947 at 3.6, 4.5, 5.8, and 8.0 microns. In all our targets, we detected excess emission in the 3-8 micron region over that expected from a brown dwarf alone. One of the exciting discoveries we made with our IRAC observations is that the star EF Eri was found to be unexpectedly bright in the mid-IR (compared to its 2MASS magnitudes). This fact highlights an opportunity for us to observe EF Eri with the IRS as a follow-up proposal. EF Eri has a flux level of ~700 ?Jy at 8 microns. Thus, we are asking for time to obtain IRS data for only this star, our brightest source. We plan to obtain SL1 (7.4-14.5 microns) and SL2 (5.2-8.7 microns) spectroscopy only. We know the IRAC fluxes so our integration toies are well constrained and the spectral region covered by SL1, SL2 will yield sufficient S/N to differentiate between cool dust (rising BB like spectrum with PAH and other molecular features allowing us to determine dust size, temperature, and disk extent) and a T type dwarf showing characteristic spectral signatures and a falling Rayleigh-Jeans tail.

Astrochemistry with the Mid-InfraRed Instrument on JWST

NASA Astrophysics Data System (ADS)

van Dishoeck, E. F.; Merín, B.; Brandl, B.; Böker, T.; Greene, T.; Meixner, M.; Ressler, M.; Rieke, G.; Waelkens, C.; Wright, G.; Miri Team

JWST-MIRI will have imaging and medium resolution (λ/Δλ ≍ 2000-3000) integral field spectroscopy with orders of magnitude improvements in sensitivity and/or spatial resolution compared with existing facilities. It will be a prime facility for astrochemical studies of gases and solids in a wide variety of objects in the next decade. 1. Introduction Mid-infrared spectroscopy is becoming a powerful tool in astrochemistry, with studies of molecules and sources that are highly complementary to those at millimeter wavelengths. Molecules without permanent dipole moments such CH4, C2H2 and CO2 can only be observed through their vibration-rotation transitions. Space-based missions open up the possibility to study molecules which are abundant in ouw own atmosphere, in particular H2O. Polycyclic Aromatic Hydrocarbons have their most prominent features at mid-infrared wavelengths, and the pure rotational transitions of the dominant molecule in the universe, H2, also occur in this band. Solid-state material is uniquely probed in the mid-infrared, including characteric bands of ices, silicates, oxides, carbides, carbonates and sulfides. The wealth of mid-infrared spectroscopy has been demonstrated by results from the ISO satellite (see van Dishoeck & Tielens 2001, van Dishoeck 2004 for reviews), by pioneering ground-based studies (Lacy et al. 1989, Evans et al. 1990) and most recently by the Spitzer Space Telescope. Targets include molecular clouds, PDRs, shocks, deeply embedded young stellar objects, UC HII regions, protoplanetary disks, planetary atmospheres, comets, evolved stars and even entire galaxies. In addition to an inventory of gaseous and solid-state material, the lines and line ratios provide powerful diagnostics of temperatures, densities, UV field, elemental abundances, etc. Systematic variations in features from region to region allow the physical and chemical processes to be traced. The MidInfraRed Instrument (MIRI) on board the 6m James Webb Space Telescope (JWST) provides the first opportunity after Spitzer for mid-infrared spectroscopy from space. The instrument will have orders of magnitude improvements in sensitivity, spatial and/or spectral resolution compared with other facilities and will be a unique facility for astrochemistry in the next decade. The combination of medium resolution spectroscopy and subarcsec spatial resolution is particularly well suited for studying gases and solids in disks around young stars and in the nuclei of (starburst) galaxies. 2. The MIRI instrument The MIRI instrument consists of an imager and a spectrometer operating in the 5-28μm wavelength range and cooled to 7 K (Wright et al. 2003, Rieke et al. 2005). The imager has a 1024×1024 pixel Si:As array with a 1.8' × 1.3' FOV with diffraction-limited image widths of 0.2" at 5.6 μm up to 0.9" at 25.5 μm. It includes low resolution (R ≍ 100) slit spectroscopy and coronography in four filter bands using fixed masks. The spectrometer has two 1024×1024 Si:As arrays and can obtain simultaneous spectral and spatial data on a few arcsec region by using four integral field units (IFUs) constructed of image slicers (see Table 1). A full 5-28.5 μm spectrum requires 3 exposures, with the dichroic/grating wheels moved between each exposure. MIRI will be at least three orders of magnitude more sensitive than any 8-m class ground-based telescope in the 5-30 μm range, a large part of which (>50 %) will be completely blocked by atmospheric features from the ground. Compared with Spitzer, MIRI will have more than an order of magnitude increase in sensitivity and spatial resolution, and a significant increase in spectral resolution. MIRI is being constructed as a joint effort between US and European institutions. It has passed its preliminary design review in March 2005. The structural and mechanical models have undergone vibration testing, and the verification models are being built. The first engineering arrays from Raytheon have been delivered. MIRI will have its critical design review in 2006 and be launched on JWST around 2013. Table 1.

The Spectral Energy Distributions of z ~ 8 Galaxies from the IRAC Ultra Deep Fields: Emission Lines, Stellar Masses, and Specific Star Formation Rates at 650 Myr

NASA Astrophysics Data System (ADS)

Labbé, I.; Oesch, P. A.; Bouwens, R. J.; Illingworth, G. D.; Magee, D.; González, V.; Carollo, C. M.; Franx, M.; Trenti, M.; van Dokkum, P. G.; Stiavelli, M.

2013-11-01

Using new ultradeep Spitzer/InfraRed Array Camera (IRAC) photometry from the IRAC Ultra Deep Field program, we investigate the stellar populations of a sample of 63 Y-dropout galaxy candidates at z ~ 8, only 650 Myr after the big bang. The sources are selected from HST/ACS+WFC3/IR data over the Hubble Ultra Deep Field (HUDF), two HUDF parallel fields, and wide area data over the CANDELS/GOODS-South. The new Spitzer/IRAC data increase the coverage in [3.6] and [4.5] to ~120h over the HUDF reaching depths of ~28 (AB,1σ). The improved depth and inclusion of brighter candidates result in direct >=3σ InfraRed Array Camera (IRAC) detections of 20/63 sources, of which 11/63 are detected at >=5σ. The average [3.6]-[4.5] colors of IRAC detected galaxies at z ~ 8 are markedly redder than those at z ~ 7, observed only 130 Myr later. The simplest explanation is that we witness strong rest-frame optical emission lines (in particular [O III] λλ4959, 5007 + Hβ) moving through the IRAC bandpasses with redshift. Assuming that the average rest-frame spectrum is the same at both z ~ 7 and z ~ 8 we estimate a rest-frame equivalent width of {W}_{[O\\,\\scriptsize{III}]\\ \\lambda \\lambda 4959,5007+H\\beta }=670^{+260}_{-170} Å contributing 0.56^{+0.16}_{-0.11} mag to the [4.5] filter at z ~ 8. The corresponding {W}_{H\\alpha }=430^{+160}_{-110} Å implies an average specific star formation rate of sSFR=11_{-5}^{+11} Gyr-1 and a stellar population age of 100_{-50}^{+100} Myr. Correcting the spectral energy distribution for the contribution of emission lines lowers the average best-fit stellar masses and mass-to-light ratios by ~3 ×, decreasing the integrated stellar mass density to \\rho ^*(z=8,M_{\\rm{UV}}<-18)=0.6^{+0.4}_{-0.3}\\times 10^6 \\,M_\\odot Mpc-3. Based on observations made with the NASA/ESA Hubble Space Telescope, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with programs #11563, 9797. Based on observations with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under NASA contract 1407. Support for this work was provided by NASA through contract 125790 issued by JPL/Caltech. Based on service mode observations collected at the European Southern Observatory, Paranal, Chile (ESO Program 073.A-0764A). Based on data gathered with the 6.5 m Magellan Telescopes located at Las Campanas Observatory, Chile.

Multi-Wavelength Views of Protostars in IC 1396

NASA Technical Reports Server (NTRS)

2003-01-01

[figure removed for brevity, see original site] Click on individual images below for larger view

[figure removed for brevity, see original site]

[figure removed for brevity, see original site]

[figure removed for brevity, see original site]

NASA's Spitzer Space Telescope has captured a glowing stellar nursery within a dark globule that is opaque at visible light. These new images pierce through the obscuration to reveal the birth of new protostars, or embryonic stars, and young stars never before seen.

The Elephant's Trunk Nebula is an elongated dark globule within the emission nebula IC 1396 in the constellation of Cepheus. Located at a distance of 2,450 light-years, the globule is a condensation of dense gas that is barely surviving the strong ionizing radiation from a nearby massive star. The globule is being compressed by the surrounding ionized gas.

The large composite image above is a product of combining data from the observatory's multiband imaging photometer and the infrared array camera. The thermal emission at 24 microns measured by the photometer (red) is combined with near-infrared emission from the camera at 3.6/4.5 microns (blue) and from 5.8/8.0 microns (green). The colors of the diffuse emission and filaments vary, and are a combination of molecular hydrogen (which tends to be green) and polycyclic aromatic hydrocarbon (brown) emissions.

Within the globule, a half dozen newly discovered protostars, or embryonic stars, are easily discernible as the bright red-tinted objects, mostly along the southern rim of the globule. These were previously undetected at visible wavelengths due to obscuration by the thick cloud ('globule body') and by dust surrounding the newly forming stars. The newborn stars form in the dense gas because of compression by the wind and radiation from a nearby massive star (located outside the field of view to the left). The winds from this unseen star are also responsible for producing the spectacular filamentary appearance of the globule itself.

The Spitzer Space Telescope also sees many newly discovered young stars, often enshrouded in dust, which may be starting the nuclear fusion that defines a star. These young stars are too cool to be seen at visible wavelengths. Both the protostars and young stars are bright in the mid-infrared because of their surrounding discs of solid material. A few of the visible-light stars in this image were found to have excess infrared emission, suggesting they are more mature stars surrounded by primordial remnants from their formation, or from crumbling asteroids and comets in their planetary systems.

A SELF-CONSISTENT MODEL OF THE CIRCUMSTELLAR DEBRIS CREATED BY A GIANT HYPERVELOCITY IMPACT IN THE HD 172555 SYSTEM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnson, B. C.; Melosh, H. J.; Lisse, C. M.

2012-12-10

Spectral modeling of the large infrared excess in the Spitzer IRS spectra of HD 172555 suggests that there is more than 10{sup 19} kg of submicron dust in the system. Using physical arguments and constraints from observations, we rule out the possibility of the infrared excess being created by a magma ocean planet or a circumplanetary disk or torus. We show that the infrared excess is consistent with a circumstellar debris disk or torus, located at {approx}6 AU, that was created by a planetary scale hypervelocity impact. We find that radiation pressure should remove submicron dust from the debris diskmore » in less than one year. However, the system's mid-infrared photometric flux, dominated by submicron grains, has been stable within 4% over the last 27 years, from the Infrared Astronomical Satellite (1983) to WISE (2010). Our new spectral modeling work and calculations of the radiation pressure on fine dust in HD 172555 provide a self-consistent explanation for this apparent contradiction. We also explore the unconfirmed claim that {approx}10{sup 47} molecules of SiO vapor are needed to explain an emission feature at {approx}8 {mu}m in the Spitzer IRS spectrum of HD 172555. We find that unless there are {approx}10{sup 48} atoms or 0.05 M{sub Circled-Plus} of atomic Si and O vapor in the system, SiO vapor should be destroyed by photo-dissociation in less than 0.2 years. We argue that a second plausible explanation for the {approx}8 {mu}m feature can be emission from solid SiO, which naturally occurs in submicron silicate ''smokes'' created by quickly condensing vaporized silicate.« less

Red but not dead: unveiling the star-forming far-infrared spectral energy distribution of SpARCS brightest cluster galaxies at 0 < z < 1.8

NASA Astrophysics Data System (ADS)

Bonaventura, N. R.; Webb, T. M. A.; Muzzin, A.; Noble, A.; Lidman, C.; Wilson, G.; Yee, H. K. C.; Geach, J.; Hezaveh, Y.; Shupe, D.; Surace, J.

2017-08-01

We present the results of a Spitzer/Herschel infrared photometric analysis of the largest (716) and the highest-redshift (z = 1.8) sample of brightest cluster galaxies (BCGs), those from the Spitzer Adaptation of the Red-Sequence Cluster Survey Given the tension that exists between model predictions and recent observations of BCGs at z < 2, we aim to uncover the dominant physical mechanism(s) guiding the stellar mass buildup of this special class of galaxies, the most massive in the Universe and uniquely residing at the centres of galaxy clusters. Through a comparison of their stacked, broad-band, infrared spectral energy distributions (SEDs) to a variety of model templates in the literature, we identify the major sources of their infrared energy output, in multiple redshift bins between 0 < z < 1.8. We derive estimates of various BCG physical parameters from the stacked νLν SEDs, from which we infer a star-forming, as opposed to a 'red and dead' population of galaxies, producing tens to hundreds of solar masses per year down to z = 0.5. This discovery challenges the accepted belief that BCGs should only passively evolve through a series of gas-poor, minor mergers since z ˜ 4, but agrees with an improved semi-analytic model of hierarchical structure formation that predicts star-forming BCGs throughout the epoch considered. We attribute the star formation inferred from the stacked infrared SEDs to both major and minor 'wet' (gas-rich) mergers, based on a lack of key signatures (to date) of cooling-flow-induced star formation, as well as a number of observational and simulation-based studies that support this scenario.

Assessment study of infrared detector arrays for low-background astronomical research

NASA Technical Reports Server (NTRS)

Ando, K. J.

1978-01-01

The current state-of-the-art of infrared detector arrays employing charge coupled devices (CCD) or charge injection devices (CID) readout are assessed. The applicability, limitations and potentials of such arrays under the low-background astronomical observing conditions of interest for SIRFT (Shuttle Infrared Telescope Facility) are determined. The following are reviewed: (1) monolithic extrinsic arrays; (2) monolithic intrinsic arrays; (3) charge injection devices; and (4) hybrid arrays.

The Y-type Brown Dwarfs: Estimates of Mass and Age from New Astrometry, Homogenized Photometry, and Near-infrared Spectroscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leggett, S. K.; Tremblin, P.; Esplin, T. L.

The survey of the mid-infrared sky by the Wide-field Infrared Survey Explorer ( WISE ) led to the discovery of extremely cold, low-mass brown dwarfs, classified as Y dwarfs, which extend the T class to lower temperatures. Twenty-four Y dwarfs are known at the time of writing. Here we present improved parallaxes for four of these, determined using Spitzer images. We give new photometry for four late-type T and three Y dwarfs and new spectra of three Y dwarfs, obtained at Gemini Observatory. We also present previously unpublished photometry taken from HST , ESO, Spitzer , and WISE archives ofmore » 11 late-type T and 9 Y dwarfs. The near-infrared data are put onto the same photometric system, forming a homogeneous data set for the coolest brown dwarfs. We compare recent models to our photometric and spectroscopic data set. We confirm that nonequilibrium atmospheric chemistry is important for these objects. Nonequilibrium cloud-free models reproduce well the near-infrared spectra and mid-infrared photometry for the warmer Y dwarfs with 425 ≤ T {sub eff} (K) ≤ 450. A small amount of cloud cover may improve the model fits in the near-infrared for the Y dwarfs with 325 ≤ T {sub eff} (K) ≤ 375. Neither cloudy nor cloud-free models reproduce the near-infrared photometry for the T {sub eff} = 250 K Y dwarf W0855. We use the mid-infrared region, where most of the flux originates, to constrain our models of W0855. We find that W0855 likely has a mass of 1.5–8 Jupiter masses and an age of 0.3–6 Gyr. The Y dwarfs with measured parallaxes are within 20 pc of the Sun and have tangential velocities typical of the thin disk. The metallicities and ages we derive for the sample are generally solar-like. We estimate that the known Y dwarfs are 3 to 20 Jupiter-mass objects with ages of 0.6–8.5 Gyr.« less

Far-infrared Line Spectra of Active Galaxies from the Herschel/PACS Spectrometer: The Complete Database

NASA Astrophysics Data System (ADS)

Fernández-Ontiveros, Juan Antonio; Spinoglio, Luigi; Pereira-Santaella, Miguel; Malkan, Matthew A.; Andreani, Paola; Dasyra, Kalliopi M.

2016-10-01

We present a coherent database of spectroscopic observations of far-IR fine-structure lines from the Herschel/Photoconductor Array Camera and Spectrometer archive for a sample of 170 local active galactic nuclei (AGNs), plus a comparison sample of 20 starburst galaxies and 43 dwarf galaxies. Published Spitzer/IRS and Herschel/SPIRE line fluxes are included to extend our database to the full 10-600 μm spectral range. The observations are compared to a set of Cloudy photoionization models to estimate the above physical quantities through different diagnostic diagrams. We confirm the presence of a stratification of gas density in the emission regions of the galaxies, which increases with the ionization potential of the emission lines. The new [O IV]{}25.9μ {{m}}/[O III]{}88μ {{m}} versus [Ne III]{}15.6μ {{m}}/[Ne II]{}12.8μ {{m}} diagram is proposed as the best diagnostic to separate (1) AGN activity from any kind of star formation and (2) low-metallicity dwarf galaxies from starburst galaxies. Current stellar atmosphere models fail to reproduce the observed [O IV]{}25.9μ {{m}}/[O III]{}88μ {{m}} ratios, which are much higher when compared to the predicted values. Finally, the ([Ne III]{}15.6μ {{m}} + [Ne II]{}12.8μ {{m}})/([S IV]{}10.5μ {{m}} +[S III]{}18.7μ {{m}}) ratio is proposed as a promising metallicity tracer to be used in obscured objects, where optical lines fail to accurately measure the metallicity. The diagnostic power of mid- to far-infrared spectroscopy shown here for local galaxies will be of crucial importance to study galaxy evolution during the dust-obscured phase at the peak of the star formation and black hole accretion activity (1\\lt z\\lt 4). This study will be addressed by future deep spectroscopic surveys with present and forthcoming facilities such as the James Webb Space Telescope, the Atacama Large Millimeter/submillimeter Array, and the Space Infrared telescope for Cosmology and Astrophysics.

A Continued Census of Mid-IR Variability from ULXs

NASA Astrophysics Data System (ADS)

Lau, Ryan; Kasliwal, Mansi; Heida, Marianne; Walton, Dom

2017-04-01

The nature of ultraluminous X-ray sources (ULXs) that radiate at luminosities >10^39 erg/s is still a mystery. ULXs are believed to be binaries with an accreting compact object and stellar mass-donor companion, but such high luminosities require accretion rates that are factors of 100 greater than the Eddington limit for accretion onto a neutron star or stellar mass black hole. The difficulties in interpreting ULXs are largely attributed to current observational challenges in determining their orbital properties as well as the properties of the mass-donor companion. Recently, near- and mid-infrared (IR) observations have been demonstrated as powerful diagnostics of the mass-donor companion and the circumstellar environment of ULXs. For example, serendipitous Spitzer/IRAC observations of the ULX Holmberg II X-1 in our Spitzer Infrared Intensive Transients Survey (SPIRITS) revealed the first detection of mid-IR variability from a ULX, where we claimed that the mid-IR emission arises from a dusty circumbinary torus in the winds of a supergiant B[e] mass-donor companion. We identified 5 additional mid-IR ULX counterparts detected by Spitzer/IRAC, one of which shows significant variability like Holmberg II X-1. Although we are finding a growing sample of ULXs exhibiting mid-IR variability, it is unclear what causes it. Notably, the week - year cadence baselines of the SPIRITS observations are inadequate for resolving variability timescales consistent with several observed ULX orbital periods. In this proposal, we request time-series observations of 6 ULXs with cadence baselines ranging from 0.5 days to 1 week in order to identify the timescales associated mid-IR variability.

Dynamic Young Stars and their Disks: A Temporal View of NGC 2264 with Spitzer and CoRoT

NASA Astrophysics Data System (ADS)

Cody, Ann Marie; Stauffer, John; Bouvier, Jèrôme

2014-01-01

Variability is a signature feature of young stars. Among the well known light curve phenomena are periodic variations attributed to surface spots and irregular changes associated with accretion or circumstellar disk material. While decades of photometric monitoring have provided a framework for classifying young star variability, we still know surprisingly little about its underlying mechanisms and connections to the surrounding disks. In the past few years, dedicated photometric monitoring campaigns from the ground and space have revolutionized our view of young stars in the time domain. We present a selection of optical and infrared time series from several recent campaigns, highlighting the Coordinated Synoptic Investigation of NGC 2264 ("CSI 2264")- a joint30-day effort with the Spitzer, CoRoT, and MOST telescopes. The extraordinary photometric precision, high cadence, and long time baseline of these observations is now enabling correlation of variability properties at very different wavelengths, corresponding to locations from the stellar surface to the inner 0.1 AU of the disk. We present some results of the CSI 2264 program, including new classes of optical/infrared behavior. Further efforts to tie observed variability features to physical models will provide insights into the inner disk environment at a time when planet formation may be underway. Based on data from the Spitzer and CoRoT missions. The CoRoT space mission was developed and is operated by the French space agency CNES, with participation of ESA-s RSSD and Science Programmes, Austria, Belgium, Brazil, Germany, and Spain.

Brown dwarf distances and atmospheres: Spitzer Parallaxes and the Keck/NIRSPEC upgrade

NASA Astrophysics Data System (ADS)

Martin, Emily C.

2018-01-01

Advances in infrared technology have been essential towards improving our understanding of the solar neighborhood, revealing a large population of brown dwarfs, which span the mass regime between planets and stars. My thesis combines near-infrared (NIR) spectroscopic and astrometric analysis of nearby low-mass stars and brown dwarfs with instrumentation work to upgrade the NIRSPEC instrument for the Keck II Telescope. I will present results from a program using Spitzer/IRAC data to measure precise locations and distances to 22 of the coldest and closest brown dwarfs. These distances allow us to constrain absolute physical properties, such as mass, radius, and age, of free-floating planetary-mass objects through comparison to atmospheric and evolutionary models. NIR spectroscopy combined with the Spitzer photometry reveals a detailed look into the atmospheres of brown dwarfs and gaseous extrasolar planets. Additionally, I will discuss the improvements we are making to the NIRSPEC instrument at Keck. NIRSPEC is a NIR echelle spectrograph, capable of R~2000 and R~25,000 observations in the 1-5 μm range. As part of the upgrade, I performed detector characterization, optical design of a new slit-viewing camera, mechanical testing, and electronics design. NIRSPEC’s increased efficiency will allow us to obtain moderate- and high-resolution NIR spectra of objects up to a magnitude fainter than the current NIRSPEC design. Finally, I will demonstrate the utility of a NIR laser frequency comb as a high-resolution calibrator. This new technology will revolutionize precision radial velocity measurements in the coming decade.

VLT/X-shooter Spectroscopy of a dusty planetary nebula discovered with Spitzer/IRS

NASA Astrophysics Data System (ADS)

Oliveira, I.; Overzier, R. A.; Pontoppidan, K. M.; van Dishoeck, E. F.; Spezzi, L.

2011-02-01

As part of a mid-infrared spectroscopic survey of young stars with the Spitzer Space Telescope, an unclassified red emission line object was discovered. Based on its high ionization state indicated by the Spitzer spectrum, this object could either be a dusty supernova remnant (SNR) or a planetary nebula (PN). In this research note, the object is classified and the available spectroscopic data are presented to the community for further analysis. UV/optical/NIR spectra were obtained during the science verification run of the VLT/X-shooter. A large number of emission lines are identified allowing the determination of the nature of this object. The presence of strong, narrow (Δv ~8 - 74 km s-1) emission lines, combined with very low line ratios of, e.g., [N ii]/Hα and [S ii]/Hα show that the object is a PN that lies at an undetermined distance behind the Serpens Molecular Cloud. This illustrates the potential of X-shooter as an efficient tool for constraining the nature of faint sources with unknown spectral properties or colors.

Spitzer IRS Spectra of Basaltic Asteroids: Preliminary Results

NASA Technical Reports Server (NTRS)

Lim, Lucy F.; Emery, Joshua P.; Moskovitz, Nick; Stewart, Heather; Marchis, Frank

2008-01-01

We present preliminary results of a Spitzer program to observe the 5.2--38 micron spectra of small basaltic asteroids using the Spitzer IRS (Infrared Spectrograph). Our targets include members of the dynamical family of the unique large differentiated asteroid 4 Vesta ("Vestoids"), four outer-main-belt basaltic asteroids whose orbits exclude them from originating on 4 Vesta, and the basaltic near-Earth asteroid (NEA) 4055 Magellan. We will compare the compositions and thermophysical properties of the non-Vestoid objects with those of the dynamical vestoids to provide insight on the extent of metal-silicate differentiation on planetsimals during the epoch of planet formation in the early Solar System. As of this writing, spectra of asteroids 10537 (1991 RY16) and 2763 Jeans have been returned. Analysis of these data are ongolng. Observations of 956 Elisa, 2653 Principia, 4215 Kamo, 7472 Kumakiri, and 1459 Magnya have been scheduled and are expected to be available by the time of the DPS meeting. NIR spectra and lightcurves o f the target asteroids are also being observed in support of this program.

The Astronomical Zoo in MIPSGAL I and II

NASA Astrophysics Data System (ADS)

Kuchar, Thomas A.; Mizuno, D.; Shenoy, S.; Paladini, R.; Kraemer, K.; Price, S.; Marleau, F.; Padgett, D.; Indebetouw, R.; Ingalls, J.; Ali, B.; Berriman, B.; Boulanger, F.; Cutri, R.; Latter, W.; Miville-Deschenes, M.; Molinari, S.; Rebull, L.; Testi, L.; Shipman, R.; Martin, P.; Carey, S.; Noriega-Crespo, A.

2006-12-01

The view of the Galactic Plane at 24 µm is breathtaking. A great part of this beauty arises from the complexity of the Interstellar Medium shaped by endless energetic events driven by HII regions, supernova explosions, Wolf-Rayets, Luminous Blue Variables, and evolved and new born massive stars. A sample of these objects is presented in this poster, gathered from the Multiband Imaging Photometer for Spitzer (MIPS) Survey of the Galactic Plane I and II (MIPSGAL; see Carey et al. 2006, this meeting). The global color properties of these objects are derived by combining the data at 24 and 70um with that from the Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE), and following similar schemes as those used in the Spitzer Surveys of the Magellanic Clouds (Bolatto et al. 2006, astroph-0608561; Meixner et al. 2006, astroph-0606356). This work is based on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with NASA. Support for this work was provided by NASA in part through an award issued by JPL/Caltech.

Mid-Infrared Observations of Possible Intergalactic Star Forming Regions in the Leo Ring

NASA Astrophysics Data System (ADS)

Giroux, Mark; Smith, B.; Struck, C.

2011-05-01

Within the Leo group of galaxies lies a gigantic loop of intergalactic gas known as the Leo Ring. Not clearly associated with any particular galaxy, its origin remains uncertain. It may be a primordial intergalactic cloud alternatively, it may be a collision ring, or have a tidal origin. Combining archival Spitzer images of this structure with published UV and optical data, we investigate the mid-infrared properties of possible knots of star formation in the ring. These sources are very faint in the mid-infrared compared to star forming regions in the tidal features of interacting galaxies. This suggests they are either deficient in dust, or they may not be associated with the ring.

Proceedings of the Third Infrared Detector Technology Workshop

NASA Technical Reports Server (NTRS)

Mccreight, Craig R. (Compiler)

1989-01-01

This volume consists of 37 papers which summarize results presented at the Third Infrared Detector Technology Workshop, held February 7-9, 1989, at Ames Research Center. The workshop focused on infrared (IR) detector, detector array, and cryogenic electronic technologies relevant to low-background space astronomy. Papers on discrete IR detectors, cryogenic readouts, extrinsic and intrinsic IR arrays, and recent results from ground-based observations with integrated arrays were given. Recent developments in the second-generation Hubble Space Telescope (HST) infrared spectrometer and in detectors and arrays for the European Space Agency's Infrared Space Observatory (ISO) are also included, as are status reports on the Space Infrared Telescope Facility (SIRTF) and the Stratospheric Observatory for Infrared Astronomy (SOFIA) projects.

Disk Evolution in Cep OB2: Results from the Spitzer Space Telescope

NASA Technical Reports Server (NTRS)

Sicilia-Aguilar Aurora; Hartmann, Lee W.; Calvet Nuria; Megeath, S. T.; Muzerolle, James; Allen, Lori; D'Alessio, Paola; Merin, Bruno; Stauffer, John; Lada, Charles;

Star Formation in Henize 206

NASA Technical Reports Server (NTRS)

2004-01-01

[figure removed for brevity, see original site] IRA-MIPS Composite

[figure removed for brevity, see original site] Visible

[figure removed for brevity, see original site] IRAC

[figure removed for brevity, see original site] MIPS

The LMC is a small satellite galaxy gravitationally bound to our own Milky Way. Yet the gravitational effects are tearing the companion to shreds in a long-playing drama of 'intergalactic cannibalism.' These disruptions lead to a recurring cycle of star birth and star death.

Astronomers are particularly interested in the LMC because its fractional content of heavy metals is two to five times lower than is seen in our solar neighborhood. [In this context, 'heavy elements' refer to those elements not present in the primordial universe. Such elements as carbon, oxygen and others are produced by nucleosynthesis and are ejected into the interstellar medium via mass loss by stars, including supernova explosions.] As such, the LMC provides a nearby cosmic laboratory that may resemble the distant universe in its chemical composition.

The primary Spitzer image, showing the wispy filamentary structure of Henize 206, is a four-color composite mosaic created by combining data from an infrared array camera (IRAC) at near-infrared wavelengths and the mid-infrared data from a multiband imaging photometer (MIPS). Blue represents invisible infrared light at wavelengths of 3.6 and 4.5 microns. Note that most of the stars in the field of view radiate primarily at these short infrared wavelengths. Cyan denotes emission at 5.8 microns, green depicts the 8.0 micron light, and red is used to trace the thermal emission from dust at 24 microns. The separate instrument images are included as insets to the main composite.

An inclined ring of emission dominates the central and upper regions of the image. This delineates a bubble of hot, x-ray emitting gas that was blown into space when a massive star died in a supernova explosion millions of years ago. The shock waves from that explosion impacted a cloud of nearby hydrogen gas, compressed it, and started a new generation of star formation. The death of one star led to the birth of many new stars. This is particularly evident in the MIPS inset, where the 24-micron emission peaks correspond to newly formed stars. The ultraviolet and visible-light photons from the new stars are absorbed by surrounding dust and re-radiated at longer infrared wavelengths, where it is detected by Spitzer.

This emission nebula was cataloged by Karl Henize (HEN-eyes) while spending 1948-1951 in South Africa doing research for his Ph.D. dissertation at the University of Michigan. Henize later became a NASA astronaut and, at age 59, became the oldest rookie to fly on the Space Shuttle during an eight-day flight of the Challenger in 1985. He died just short of his 67th birthday in 1993 while attempting to climb the north face of Mount Everest, the world's highest peak.

The Spitzer-IRAC/MIPS Extragalactic Survey (SIMES) in the South Ecliptic Pole Field

NASA Astrophysics Data System (ADS)

Baronchelli, I.; Scarlata, C.; Rodighiero, G.; Franceschini, A.; Capak, P. L.; Mei, S.; Vaccari, M.; Marchetti, L.; Hibon, P.; Sedgwick, C.; Pearson, C.; Serjeant, S.; Menéndez-Delmestre, K.; Salvato, M.; Malkan, M.; Teplitz, H. I.; Hayes, M.; Colbert, J.; Papovich, C.; Devlin, M.; Kovacs, A.; Scott, K. S.; Surace, J.; Kirkpatrick, J. D.; Atek, H.; Urrutia, T.; Scoville, N. Z.; Takeuchi, T. T.

2016-03-01

We present the Spitzer-IRAC/MIPS Extragalactic survey (SIMES) in the South Ecliptic Pole field. The large area covered (7.7 deg2), together with one of the lowest Galactic cirrus emissions in the entire sky and a very extensive coverage by Spitzer, Herschel, Akari, and GALEX, make the SIMES field ideal for extragalactic studies. The elongated geometry of the SIMES area (≈4:1), allowing for significant cosmic variance reduction, further improves the quality of statistical studies in this field. Here we present the reduction and photometric measurements of the Spitzer/IRAC data. The survey reaches depths of 1.93 and 1.75 μJy (1σ) at 3.6 and 4.5 μm, respectively. We discuss the multiwavelength IRAC-based catalog, completed with optical, mid-, and far-IR observations. We detect 341,000 sources with {F}3.6μ {{m}}≥slant 3σ . Of these, 10% have an associated 24 μm counterpart, while 2.7% have an associated SPIRE source. We release the catalog through the NASA/IPAC Infrared Science Archive. Two scientific applications of these IRAC data are presented in this paper. First, we compute integral number counts at 3.6 μm. Second, we use the [3.6]-[4.5] color index to identify galaxy clusters at z > 1.3. We select 27 clusters in the full area, a result consistent with previous studies at similar depth.

Comparative Studies of the Dust around Red Supergiant and Oxygen-Rich Asymptotic Giant Branch Stars in the Local Universe

NASA Astrophysics Data System (ADS)

Sargent, Benjamin; Srinivasan, Sundar; Speck, Angela K.; Volk, Kevin; Kemper, Ciska; Reach, William; Lagadec, Eric; Bernard, Jean-Philippe; McDonald, Iain; Meixner, Margaret; Sloan, Greg; Jones, Olivia

2015-08-01

We analyze the dust emission features seen in Spitzer Space Telescope Infrared Spectrograph (IRS) spectra of red supergiant (RSG) and oxygen-rich asymptotic giant branch (AGB) stars in the Large Magellanic Cloud and Small Magellanic Cloud galaxies and in various Milky Way globular clusters. The spectra come from the Spitzer Legacy program SAGE-Spectroscopy (PI: F. Kemper), the Spitzer program SMC-Spec (PI: G. Sloan), and other archival Spitzer-IRS programs. The broad 10 and 20 μm emission features attributed to amorphous dust of silicate composition seen in the spectra show evidence for systematic differences in the centroid of both emission features between O-rich AGB and RSG populations. Radiative transfer modeling using the GRAMS grid of models of AGB and RSG stars suggests that the centroid differences are due to differences in dust properties. We investigate differences in dust composition, size, shape, etc that might be responsible for these spectral differences. We explore how these differences may arise from the different circumstellar environments around RSG and O-rich AGB stars and assess effects of varying metallicity (LMC versus SMC versus Milky Way globular cluster) and other properties (mass-loss rate, luminosity, etc.) on the dust originating from these stars. BAS acknowledges funding from NASA ADAP grant NNX13AD54G.

Detailed modelling of a large sample of Herschel sources in the Lockman Hole: identification of cold dust and of lensing candidates through their anomalous SEDs★

NASA Astrophysics Data System (ADS)

Rowan-Robinson, Michael; Wang, Lingyu; Wardlow, Julie; Farrah, Duncan; Oliver, Seb; Bock, Jamie; Clarke, Charlotte; Clements, David; Ibar, Edo; Gonzalez-Solares, Eduardo; Marchetti, Lucia; Scott, Douglas; Smith, Anthony; Vaccari, Mattia; Valtchanov, Ivan

2014-12-01

We have studied in detail a sample of 967 SPIRE sources with 5σ detections at 350 and 500 μm and associations with Spitzer-SWIRE 24 μm galaxies in the HerMES-Lockman survey area, fitting their mid- and far-infrared, and submillimetre, spectral energy distributions (SEDs) in an automatic search with a set of six infrared templates. For almost 300 galaxies, we have modelled their SEDs individually to ensure the physicality of the fits. We confirm the need for the new cool and cold cirrus templates, and also of the young starburst template, introduced in earlier work. We also identify 109 lensing candidates via their anomalous SEDs and provide a set of colour-redshift constraints which allow lensing candidates to be identified from combined Herschel and Spitzer data. The picture that emerges of the submillimetre galaxy population is complex, comprising ultraluminous and hyperluminous starbursts, lower luminosity galaxies dominated by interstellar dust emission, lensed galaxies and galaxies with surprisingly cold (10-13 K) dust. 11 per cent of 500 μm selected sources are lensing candidates. 70 per cent of the unlensed sources are ultraluminous infrared galaxies and 26 per cent are hyperluminous. 34 per cent are dominated by optically thin interstellar dust (`cirrus') emission, but most of these are due to cooler dust than is characteristic of our Galaxy. At the highest infrared luminosities we see SEDs dominated by M82, Arp 220 and young starburst types, in roughly equal proportions.

SERVS: the Spitzer Extragalactic Representative Volume Survey

NASA Astrophysics Data System (ADS)

Lacy, Mark; Afonso, Jose; Alexander, Dave; Best, Philip; Bonfield, David; Castro, Nieves; Cava, Antonio; Chapman, Scott; Dunlop, James; Dyke, Eleanor; Edge, Alastair; Farrah, Duncan; Ferguson, Harry; Foucaud, Sebastian; Franceschini, Alberto; Geach, Jim; Gonzales, Eduardo; Hatziminaoglou, Evanthia; Hickey, Samantha; Ivison, Rob; Jarvis, Matt; Le Fèvre, Olivier; Lonsdale, Carol; Maraston, Claudia; McLure, Ross; Mortier, Angela; Oliver, Seb; Ouchi, Masami; Parish, Glen; Perez-Fournon, Ismael; Petric, Andreea; Pierre, Mauguerite; Readhead, Tony; Ridgway, Susan; Romer, Katherine; Rottgering, Huub; Rowan-Robinson, Michael; Sajina, Anna; Seymour, Nick; Smail, Ian; Surace, Jason; Thomas, Peter; Trichas, Markos; Vaccari, Mattia; Verma, Aprajita; Xu, Kevin; van Kampen, Eelco

2008-12-01

We will use warm Spitzer to image 18deg^2 of sky to microJy depth. This is deep enough to undertake a complete census of massive galaxies from z~6 to ~1 in a volume ~0.8Gpc^3, large enough to overcome the effects of cosmic variance, which place severe limitations on the conclusions that can be drawn from smaller fields. We will greatly enhance the diagnostic power of the Spitzer data by performing most of this survey in the region covered by the near-IR VISTA-VIDEO survey, and in other areas covered by near-IR, Herschel and SCUBA2 surveys. We will build complete near-infrared spectral energy distributions using the superb datasets from VIDEO, in conjunction with our Spitzer data, to derive accurate photometric redshifts and the key properties of stellar mass and star formation rates for a large sample of high-z galaxies. Obscured star formation rates and dust-shrouded BH growth phases will be uncovered by combining the Spitzer data with the Herschel and SCUBA2 surveys. We will thus build a complete picture of the formation of massive galaxies from z~6, where only about 1% of the stars in massive galaxies have formed, to z~1 where ~50% of them haveE Our large volume will allow us to also find examples of rare objects such as high-z quasars (~10-100 at z>6.5), high-z galaxy clusters (~20 at z>1.5 with dark halo masses >10^14 solar masses), and evaluate how quasar activity and galaxy environment affect star formation. This survey makes nearly optimal use of warm Spitzer; (a) all of the complementary data is either taken or will be taken in the very near future, and will be immediately publicly accessible, (b) the slew overheads are relatively small, (c) the observations are deep enough to detect high redshift galaxies but not so deep that source confusion reduces the effective survey area.

Night Vision

NASA Astrophysics Data System (ADS)

Rowan-Robinson, Michael

2013-05-01

Preface; 1. Introduction; 2. William Herschel opens up the invisible universe; 3. 1800-1950: slow progress - the moon, planets, bright stars, and the discovery of interstellar dust; 4. Dying stars shrouded in dust and stars being born: the emergence of infrared astronomy in the 60s and 70s; 5. Birth of far infrared and submillimetre astronomy: clouds of dust and molecules in our Galaxy; 6. The cosmic microwave background, echo of the Big Bang; 7. The Infrared Astronomical Satellite and the opening up of extragalactic infrared astronomy: starbursts and active galactic nuclei; 8. The Cosmic Background Explorer and the ripples, the Wilkinson Microwave Anisotropy Explorer, and dark energy; 9. Giant ground-based infrared and submillimetre telescopes; 10. The Infrared Space Observatory and the Spitzer Space Telescope: the star-formation history of the universe and infrared galaxy populations; 11. Our dusty Solar System, debris disks and the search for exoplanets; 12. The future: pioneering space missions and giant ground-based telescopes; Notes; Credits for illustrations; Further reading; Bibliography; Glossary; Index of names; Index.

Three Great Eyes on Kepler Supernova Remnant

NASA Image and Video Library

2004-10-06

NASA's three Great Observatories -- the Hubble Space Telescope, the SpitzerSpace Telescope, and the Chandra X-ray Observatory -- joined forces to probe theexpanding remains of a supernova, called Kepler's supernova remnant, first seen 400 years ago by sky watchers, including astronomer Johannes Kepler. The combined image unveils a bubble-shaped shroud of gas and dust that is 14light-years wide and is expanding at 4 million miles per hour (2,000 kilometersper second). Observations from each telescope highlight distinct features of thesupernova remnant, a fast-moving shell of iron-rich material from the explodedstar, surrounded by an expanding shock wave that is sweeping up interstellar gasand dust. Each color in this image represents a different region of the electromagneticspectrum, from X-rays to infrared light. These diverse colors are shown in thepanel of photographs below the composite image. The X-ray and infrared datacannot be seen with the human eye. By color-coding those data and combining themwith Hubble's visible-light view, astronomers are presenting a more completepicture of the supernova remnant. Visible-light images from the Hubble telescope (colored yellow) reveal where the supernova shock wave is slamming into the densest regions of surrounding gas.The bright glowing knots are dense clumps from instabilities that form behindthe shock wave. The Hubble data also show thin filaments of gas that look likerippled sheets seen edge-on. These filaments reveal where the shock wave isencountering lower-density, more uniform interstellar material. The Spitzer telescope shows microscopic dust particles (colored red) that havebeen heated by the supernova shock wave. The dust re-radiates the shock wave'senergy as infrared light. The Spitzer data are brightest in the regionssurrounding those seen in detail by the Hubble telescope. The Chandra X-ray data show regions of very hot gas, and extremely high-energyparticles. The hottest gas (higher-energy X-rays, colored blue) is locatedprimarily in the regions directly behind the shock front. These regions alsoshow up in the Hubble observations, and also align with the faint rim of glowingmaterial seen in the Spitzer data. The X-rays from the region on the lower left(colored blue) may be dominated by extremely high-energy electrons that wereproduced by the shock wave and are radiating at radio through X-ray wavelengthsas they spiral in the intensified magnetic field behind the shock front. CoolerX-ray gas (lower-energy X-rays, colored green) resides in a thick interior shelland marks the location of heated material expelled from the exploded star. Kepler's supernova, the last such object seen to explode in our Milky Waygalaxy, resides about 13,000 light-years away in the constellation Ophiuchus. The Chandra observations were taken in June 2000, the Hubble in August 2003;and the Spitzer in August 2004. http://photojournal.jpl.nasa.gov/catalog/PIA06907

Experimental Demonstration of Adaptive Infrared Multispectral Imaging Using Plasmonic Filter Array (Postprint)

DTIC Science & Technology

2016-10-10

AFRL-RX-WP-JA-2017-0189 EXPERIMENTAL DEMONSTRATION OF ADAPTIVE INFRARED MULTISPECTRAL IMAGING USING PLASMONIC FILTER ARRAY...March 2016 – 23 May 2016 4. TITLE AND SUBTITLE EXPERIMENTAL DEMONSTRATION OF ADAPTIVE INFRARED MULTISPECTRAL IMAGING USING PLASMONIC FILTER ARRAY...experimental demonstration of adaptive multispectral imagery using fabricated plasmonic spectral filter arrays and proposed target detection scenarios

Comet 'Bites the Dust' Around Dead Star

NASA Technical Reports Server (NTRS)

2006-01-01

[figure removed for brevity, see original site] Infrared Spectrometer Graph

This artist's concept illustrates a comet being torn to shreds around a dead star, or white dwarf, called G29-38. NASA's Spitzer Space Telescope observed a cloud of dust around this white dwarf that may have been generated from this type of comet disruption. The findings suggest that a host of other comet survivors may still orbit in this long-dead solar system.

The white dwarf G29-38 began life as a star that was about three times as massive as our sun. Its death involved the same steps that the sun will ultimately undergo billions of years from now. According to theory, the G29-38 star became brighter and brighter as it aged, until it bloated up into a dying star called a red giant. This red giant was large enough to engulf and evaporate any terrestrial planets like Earth that happened to be in its way. Later, the red giant shed its outer atmosphere, leaving behind a shrunken skeleton of star, called a white dwarf. If the star did host a planetary system, outer planets akin to Jupiter and Neptune and a remote ring of icy comets would remain.

The Spitzer observations provide observational evidence for this orbiting outpost of comet survivors. Astronomers speculate that one such comet was knocked into the inner regions of G29-38, possibly by an outer planet. As the comet approached very close to the white dwarf, it may have been torn apart by the star's tidal forces. Eventually, all that would be left of the comet is a disk of dust.

This illustration shows a comet in the process of being pulverized: part of it still exists as a chain of small clumps, while the rest has already spread out into a dusty disk. Comet Shoemaker-Levy 9 broke apart in a similar fashion when it plunged into Jupiter in 1994. Evidence for Comets Found in Dead Star's Dust The graph of data, or spectrum, from NASA's Spitzer Space Telescope indicates that a dead star, or white dwarf, called G29-38, is shrouded by a cloud of dust. The data also demonstrate that this dust contains some of the same types of minerals found in comet Hale-Bopp.

The findings tell a possible tale of solar system survival. Though the dust seen by Spitzer is likely from a comet that recently perished, its presence suggests that an icy distant ring of comets may still orbit the dead star.

These data were collected by Spitzer's infrared spectrometer, an instrument that cracks light open like a geode, revealing its coveted components. In this spectrum, light from the white dwarf is on the left, at ultraviolet and visible wavelengths. The spectrum on the right, at infrared wavelengths longer than about 2 microns, shows much more light than can be explained by a white dwarf alone. The bump seen around a wavelength of 10 microns offers a clue to the source of this excess infrared light. It signifies the presence of silicate minerals, which are found in our own solar system on Earth, in sandy beaches, and in comets and asteroids. These silicate grains appear to be very small like those in comets, so astronomers favor the theory that a comet recently broke apart around the dead star.

VizieR Online Data Catalog: Multiwavelength study of HII region S311 (Yadav+, 2016)

NASA Astrophysics Data System (ADS)

Yadav, R. K.; Pandey, A. K.; Sharma, S.; Ojha, D. K.; Samal, M. R.; Mallick, K. K.; Jose, J.; Ogura, K.; Richichi, A.; Irawati, P.; Kobayashi, N.; Eswaraiah, C.

2017-11-01

We observed the HII region S311 (centred on RA(2000)=07:52:24, DE(2000)=-26:24:58.40) in NIR broad-bands J (1.25um), H (1.63um) and Ks (2.14um) on 2010 March 3 using the Infrared Side Port Imager (ISPI) camera mounted on the CTIO Blanco 4-m telescope. We consider only those sources having error <0.1mag in all three bands, resulting in a final catalogue of 2671 point sources. The Spitzer-IRAC observations for the S311 region (PID 20726) were made on 2006 May 3 using the 3.6, 4.5, 5.8 and 8.0um bands and were downloaded from the Spitzer heritage archive (SHA). (4 data files).

VizieR Online Data Catalog: Spitzer IRAC events observed in crowded fields (Calchi+, 2015)

NASA Astrophysics Data System (ADS)

Calchi Novati, S.; Gould, A.; Yee, J. C.; Beichman, C.; Bryden, G.; Carey, S.; Fausnaugh, M.; Gaudi, B. S.; Henderson, C. B.; Pogge, R. W.; Shvartzvald, Y.; Wibking, B.; Zhu, W.; Spitzer Team; Udalski, A.; Poleski, R.; Pawlak, M.; Szymanski, M. K.; Skowron, J.; Mroz, P.; Kozlowski, S.; Wyrzykowski, L.; Pietrukowicz, P.; Pietrzynski, G.; Soszynski, I.; Ulaczyk, K.; OGLE Group

2017-10-01

In Table 1 we list the 170 events monitored in 2015. For each, we report the event name, the coordinates, the first and last day of observation, and the number of observed epochs. The events were chosen based on the microlensing alerts provided by the OGLE (Udalski et al. 2015AcA....65....1U) and MOA (Bond et al. 2004ApJ...606L.155B) collaborations. The current analysis is based on the preliminary reduced data made available by the Spitzer Science Center almost in real time (on average, 2-3 days after the observations). The final reduction of the data is now publicly available at the NASA/IPAC Infrared Science Database (IRSA, http://irsa.ipac.caltech.edu/frontpage/). (1 data file).

Polycyclic Aromatic Hydrocarbons and Infrared Astrophysics with Spitzer

NASA Technical Reports Server (NTRS)

Hudgins, Douglas M.; Allamandola, L. J.

2004-01-01

Over the past fifteen years, thanks to significant, parallel advancements in observational, experimental, and theoretical techniques, tremendous strides have been made in our understanding of the role that carbon-rich plays in the interstellar medium (ISM). Twenty years ago, the possible existence of an abundant population of large, carbon-rich molecules in the ISM was unthinkable. Today, the unmistakable spectroscopic signatures of polycyclic aromatic hydrocarbons (PAHs) - shockingly large molecules by the standards of traditional interstellar chemistry -are recognized throughout the Universe. In this presentation, we will examine the current state of the interstellar PAH model and explore how this data, in conjunction with the unparalleled observational data provided by the Spitzer Space Telescope, can be used to draw ever-deeper insights into the physical and chemical natures of a wide range of astrophysical environments.

Swift, INTEGRAL, RXTE, and Spitzer Reveal IGR J16283-4838

NASA Technical Reports Server (NTRS)

Beckmann, V.; Gehrels, N.; Markwardt, C.; Barthelmy S.; Soldi, S.; Paizis, A.; Mowlavi, N.; Kennca, J. A.; Burrows, D. N.; Chester, M.

2005-01-01

We present the first combined study of the recently discovered source IGR J16283-4838 with Swift, INTEGRAL, and RXTE. The source, discovered by INTEGRAL on April 7, 2005, shows a highly absorbed (variable N(sub H) = 0.4-1.7 x 10(exp 23) /sq cm) and flat (Gamma approx. 1) spectrum in the Swift/XRT and RXTE/PCA data. No optical counterpart is detectable (V > 20 mag), but a possible infrared counterpart within the Swift/XRT error radius is detected in the 2MASS and Spitzer/GLIMPSE survey. The observations suggest that IGR J16283-4838 is a high mass X-ray binary containing a neutron star embedded in Compton thick material. This makes IGR J16283-4838 a member of the class of highly absorbed HMXBs, discovered by INTEGRAL.

Watching a Black Hole Feed: Sgr A* in the X-ray and Infrared

NASA Astrophysics Data System (ADS)

Fazio, Giovanni

2017-09-01

Black hole accretion drives extreme astrophysical phenomena in the universe. Sgr A*, the nearest supermassive black hole, is highly variable, but sparse data and short observations preclude determination of its emission physics. Despite enormous advances in accretion models in recent years, even the radiation mechanisms of Sgr A* are still unknown. Because the needed information is encoded in the time-dependent relationship between X-ray and IR emission, we propose four new epochs of Chandra monitoring with Spitzer at 4.5 microns. This will double the exposure time for X-ray flares where the NIR state is known, moving us out of the realm of small-number statistics and enabling diagnostics of the true X-ray/IR relationship. This will be the final chance for Chandra+Spitzer observations.

NGC 6334 V revisited: The complex nature of the infrared nebula

NASA Astrophysics Data System (ADS)

Tapia, M.; Persi, P.; Roth, M.

2017-07-01

A comprehensive analysis is presented of the most recent infrared observations of the small, very young and enigmatic infrared nebula associated with NGC 6334-V. We re-analized images from the Spitzer/IRAC (3.6 a 8 μm), Herschel/SPIRE/PACS (70 a 500 μm), VISTA (1.2 a 2.2 μm), VLT/VISIR (11.3 a 18.7 μm) and HST/NICMOS (2.0 μm) archives. The very high spatial resolution from the latter two sets, combined with very recent sub-millimetre maps, allow us to suggest several possible star-formation scenarios that explain the observed infrared and radio properties of the region. Evidence is provided of the presence of a small population of low and medium-mass young stars embedded in the infrared reflection nebulosity NGC 6334 V that coexist with the nearby much younger Class 0 protostars.

An Optical and Infrared Time-domain Study of the Supergiant Fast X-Ray Transient Candidate IC 10 X-2

NASA Astrophysics Data System (ADS)

Kwan, Stephanie; Lau, Ryan M.; Jencson, Jacob; Kasliwal, Mansi M.; Boyer, Martha L.; Ofek, Eran; Masci, Frank; Laher, Russ

2018-03-01

We present an optical and infrared (IR) study of IC 10 X-2, a high-mass X-ray binary in the galaxy IC 10. Previous optical and X-ray studies suggest that X-2 is a Supergiant Fast X-ray Transient: a large-amplitude (factor of ∼100), short-duration (hours to weeks) X-ray outburst on 2010 May 21. We analyze R- and g-band light curves of X-2 from the intermediate Palomar Transient Factory taken between 2013 July 15 and 2017 February 14 that show high-amplitude (≳1 mag), short-duration (≲8 days) flares and dips (≳0.5 mag). Near-IR spectroscopy of X-2 from Palomar/TripleSpec show He I, Paschen-γ, and Paschen-β emission lines with similar shapes and amplitudes as those of luminous blue variables (LBVs) and LBV candidates (LBVc). Mid-IR colors and magnitudes from Spitzer/Infrared Array Camera photometry of X-2 resemble those of known LBV/LBVcs. We suggest that the stellar companion in X-2 is an LBV/LBVc and discuss possible origins of the optical flares. Dips in the optical light curve are indicative of eclipses from optically thick clumps formed in the winds of the stellar counterpart. Given the constraints on the flare duration (0.02–0.8 days) and the time between flares (15.1 ± 7.8 days), we estimate the clump volume filling factor in the stellar winds, f V , to be 0.01< {f}V< 0.71, which overlaps with values measured from massive star winds. In X-2, we interpret the origin of the optical flares as the accretion of clumps formed in the winds of an LBV/LBVc onto the compact object.

Amazing Andromeda Galaxy

NASA Technical Reports Server (NTRS)

2006-01-01

The many 'personalities' of our great galactic neighbor, the Andromeda galaxy, are exposed in this new composite image from NASA's Galaxy Evolution Explorer and the Spitzer Space Telescope.

The wide, ultraviolet eyes of Galaxy Evolution Explorer reveal Andromeda's 'fiery' nature -- hotter regions brimming with young and old stars. In contrast, Spitzer's super-sensitive infrared eyes show Andromeda's relatively 'cool' side, which includes embryonic stars hidden in their dusty cocoons.

Galaxy Evolution Explorer detected young, hot, high-mass stars, which are represented in blue, while populations of relatively older stars are shown as green dots. The bright yellow spot at the galaxy's center depicts a particularly dense population of old stars.

Swaths of red in the galaxy's disk indicate areas where Spitzer found cool, dusty regions where stars are forming. These stars are still shrouded by the cosmic clouds of dust and gas that collapsed to form them.

Together, Galaxy Evolution Explorer and Spitzer complete the picture of Andromeda's swirling spiral arms. Hints of pinkish purple depict regions where the galaxy's populations of hot, high-mass stars and cooler, dust-enshrouded stars co-exist.

Located 2.5 million light-years away, the Andromeda is our largest nearby galactic neighbor. The galaxy's entire disk spans about 260,000 light-years, which means that a light beam would take 260,000 years to travel from one end of the galaxy to the other. By comparison, our Milky Way galaxy's disk is about 100,000 light-years across.

This image is a false color composite comprised of data from Galaxy Evolution Explorer's far-ultraviolet detector (blue), near-ultraviolet detector (green), and Spitzer's multiband imaging photometer at 24 microns (red).

Bubbly Little Star

NASA Technical Reports Server (NTRS)

2007-01-01

In this processed Spitzer Space Telescope image, baby star HH 46/47 can be seen blowing two massive 'bubbles.' The star is 1,140 light-years away from Earth.

The infant star can be seen as a white spot toward the center of the Spitzer image. The two bubbles are shown as hollow elliptical shells of bluish-green material extending from the star. Wisps of green in the image reveal warm molecular hydrogen gas, while the bluish tints are formed by starlight scattered by surrounding dust.

These bubbles formed when powerful jets of gas, traveling at 200 to 300 kilometers per second, or about 120 to 190 miles per second, smashed into the cosmic cloud of gas and dust that surrounds HH 46/47. The red specks at the end of each bubble show the presence of hot sulfur and iron gas where the star's narrow jets are currently crashing head-on into the cosmic cloud's gas and dust material.

Whenever astronomers observe a star, or snap a stellar portrait, through the lens of any telescope, they know that what they are seeing is slightly blurred. To clear up the blurring in Spitzer images, astronomers at the Jet Propulsion Laboratory developed an image processing technique for Spitzer called Hi-Res deconvolution.

This process reduces blurring and makes the image sharper and cleaner, enabling astronomers to see the emissions around forming stars in greater detail. When scientists applied this image processing technique to the Spitzer image of HH 46/47, they were able to see winds from the star and jets of gas that are carving the celestial bubbles.

This infrared image is a three-color composite, with data at 3.6 microns represented in blue, 4.5 and 5.8 microns shown in green, and 24 microns represented as red.

Administrator Bolden Delivers Speech at AAS

NASA Image and Video Library

2010-01-05

NASA Administrator Charles Bolden speaks at the 215th meeting of the American Astronomical Society (AAS) in Washington on Tuesday, Jan. 5, 2009. Throughout the meeting, NASA research and mission highlights will be presented from missions that include Kepler, the Spitzer Space Telescope, the Hubble Space Telescope, and the newly launched Wide-field Infrared Survey Explorer, or WISE. Photo Credit: (NASA/Bill Ingalls)

Disentangling the Origin and Heating Mechanism of Supernova Dust: Late-Time Spitzer Spectroscopy of the Type IIn SN 2005ip

NASA Technical Reports Server (NTRS)

Fox, Ori D.; Chevalier, Roger A.; Dwek, Eli; Skrutskie, Michael F.; Sugerman, Ben E. K.; Leisenring, Jarron M.

2010-01-01

This paper presents late-time near-infrared and Spitzer mid-infrared photometric and spectroscopic observations of warm dust in the Type IIn SN 2005ip in NGC 2906. The spectra show evidence for two dust components with different temperatures. Spanning the peak of the thermal emission, these observations provide strong constraints on the dust mass, temperature, and luminosity, which serve as critical diagnostics for disentangling the origin and heating mechanism of each component. The results suggest the warmer dust has a mass of approx. 5 x 10(exp -4) Solar Mass and originates from newly formed dust in the ejecta, continuously heated by the circumstellar interaction. By contrast, the cooler component likely originates from a circumstellar shock echo that forms from the heating of a large, pre-existing dust shell approx. 0.01 - 0.05 Solar Mass by the late-time circumstellar interaction. The progenitor wind velocity derived from the blue edge of the He I 1.083 micro P Cygni profile indicates a progenitor eruption likely formed this dust shell approx.100 years prior to the supernova explosion, which is consistent with a Luminous Blue Variable (LBV) progenitor star. Subject