Sample records for spectrograph iris launch

  1. Public Watches IRIS Launch Broadcast at NASA Ames (Reporter Pkg)

    NASA Image and Video Library

    2013-06-27

    Crowds of space enthusiasts gathered at Ames Research Center to witness the broadcast of NASA's Interface Region Imaging Spectrograph or IRIS Mission as it launched from an aircraft out of Vandenberg Air Force Base in California. Speakers shared insights about the IRIS Mission and attendees cheered as the Pegasus rocket successfully separated from the L-1011 launch aircraft and proceeded to fire its rockets and launch into a polar orbit around the Earth.

  2. KSC-2013-3005

    NASA Image and Video Library

    2013-06-27

    VANDENBERG AFB, Calif. – An Orbital Sciences L-1011 carrier aircraft flies over the Pacific Ocean off the California coast on a mission to launch NASA's IRIS spacecraft into low-Earth orbit. IRIS, short for Interface Region Imaging Spectrograph, was launched aboard an Orbital Sciences Pegasus XL rocket released from the bottom of the L-1011.Photo credit: NASA/Lori Losey

  3. KSC-2013-3003

    NASA Image and Video Library

    2013-06-27

    VANDENBERG AFB, Calif. – An Orbital Sciences L-1011 carrier aircraft flies over the Pacific Ocean off the California coast on a mission to launch NASA's IRIS spacecraft into low-Earth orbit. IRIS, short for Interface Region Imaging Spectrograph, was launched aboard an Orbital Sciences Pegasus XL rocket released from the bottom of the L-1011.Photo credit: NASA/Lori Losey

  4. KSC-2013-3004

    NASA Image and Video Library

    2013-06-27

    VANDENBERG AFB, Calif. – An Orbital Sciences L-1011 carrier aircraft flies over the Pacific Ocean off the California coast on a mission to launch NASA's IRIS spacecraft into low-Earth orbit. IRIS, short for Interface Region Imaging Spectrograph, was launched aboard an Orbital Sciences Pegasus XL rocket released from the bottom of the L-1011.Photo credit: NASA/Lori Losey

  5. IRIS Mission Operations Director's Colloquium

    NASA Technical Reports Server (NTRS)

    Carvalho, Robert; Mazmanian, Edward A.

    2014-01-01

    Pursuing the Mysteries of the Sun: The Interface Region Imaging Spectrograph (IRIS) Mission. Flight controllers from the IRIS mission will present their individual experiences on IRIS from development through the first year of flight. This will begin with a discussion of the unique nature of IRISs mission and science, and how it fits into NASA's fleet of solar observatories. Next will be a discussion of the critical roles Ames contributed in the mission including spacecraft and flight software development, ground system development, and training for launch. This will be followed by experiences from launch, early operations, ongoing operations, and unusual operations experiences. The presentation will close with IRIS science imagery and questions.

  6. 2014 Summer Series - Robert Carvalho - Pursuing the Mysteries of the Sun: The IRIS Mission

    NASA Image and Video Library

    2014-06-19

    Pursuing the Mysteries of the Sun: The Interface Region Imaging Spectrograph (IRIS) Mission. Flight controllers from the IRIS mission will present their individual experiences on IRIS from development through the first year of flight. This will begin with a discussion of the unique nature of IRIS's mission and science, and how it fits into NASA's fleet of solar observatories. Next will be a discussion of the critical roles Ames contributed in the mission including spacecraft and flight software development, ground system development, and training for launch. This will be followed by experiences from launch, early operations, ongoing operations, and unusual operations experiences. The presentation will close with IRIS science imagery and questions.

  7. KSC-2013-2483

    NASA Image and Video Library

    2013-05-29

    VANDENBERG AFB, Calif. - A mission logo decal for the launch of NASA's IRIS solar observatory aboard an Orbital Sciences Pegasus XL rocket. The decal is on the side of the Pegasus. Engineers are working inside a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Randy Beaudoin

  8. KSC-2013-2484

    NASA Image and Video Library

    2013-05-29

    VANDENBERG AFB, Calif. - A mission logo decal for the launch of NASA's IRIS solar observatory aboard an Orbital Sciences Pegasus XL rocket. The decal is on the side of the Pegasus. Engineers are working inside a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Randy Beaudoin

  9. The Interface Region Imaging Spectrograph (IRIS) Small Explorer

    NASA Astrophysics Data System (ADS)

    de Pontieu, B.; Title, A. M.; Schryver, C. J.; Lemen, J. R.; Golub, L.; Kankelborg, C. C.; Carlsson, M.

    2009-12-01

    The Interface Region Imaging Spectrograph (IRIS) was recently selected as a small explorer mission by NASA. The primary goal of IRIS is to understand how the solar atmosphere is energized. The IRIS investigation combines advanced numerical modeling with a high resolution 20 cm UV imaging spectrograph that will obtain spectra covering temperatures from 4,500 to 10 MK in three wavelength ranges (1332-1358 Angstrom, 1390-1406 Angstrom and 2785-2835 Angstrom) and simultaneous images covering temperatures from 4,500 K to 65,000 K. IRIS will obtain UV spectra and images with high resolution in space (1/3 arcsec) and time (1s) focused on the chromosphere and transition region of the Sun, a complex dynamic interface region between the photosphere and corona. In this region, all but a few percent of the non-radiative energy leaving the Sun is converted into heat and radiation. IRIS fills a crucial gap in our ability to advance Sun-Earth connection studies by tracing the flow of energy and plasma through this foundation of the corona and heliosphere. The IRIS investigation is led by PI Alan Title (LMSAL) with major participation by the Harvard Smithsonian Astrophysical Observatory, Montana State University, NASA Ames Research Center, Stanford University and the University of Oslo (Norway). IRIS is scheduled for launch in late 2012, and will have a nominal two year mission lifetime.

  10. KSC-2013-2485

    NASA Image and Video Library

    2013-05-29

    VANDENBERG AFB, Calif. - An Orbital Sciences Pegasus XL rocket undergoes launch preparations inside a hangar at Vandenberg Air Force Base for NASA's IRIS mission, short for Interface Region Imaging Spectrograph. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Randy Beaudoin

  11. KSC-2013-2486

    NASA Image and Video Library

    2013-05-29

    VANDENBERG AFB, Calif. - An Orbital Sciences Pegasus XL rocket undergoes launch preparations inside a hangar at Vandenberg Air Force Base for NASA's IRIS mission, short for Interface Region Imaging Spectrograph. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Randy Beaudoin

  12. KSC-2013-2885

    NASA Image and Video Library

    2013-06-24

    VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, mission managers participate in a pre-launch dress rehearsal in the Launch Vehicle Data Center for NASA’s Interface Region Imaging Spectrograph, or IRIS, solar observatory. Scheduled for launch from Vandenberg on June 26 aboard an Orbital Sciences Pegasus XL rocket, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region in to the sun’s corona using spectrometry and imaging. The IRIS mission will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. The interface region, located between the sun’s visible surface and upper atmosphere, is where most of the sun’s ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth’s climate. For more information, visit http://www.nasa.gov/iris. Photo credit: NASA/Daniel Casper

  13. KSC-2013-2888

    NASA Image and Video Library

    2013-06-24

    VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, mission managers participate in a pre-launch dress rehearsal in the Launch Vehicle Data Center for NASA’s Interface Region Imaging Spectrograph, or IRIS, solar observatory. Scheduled for launch from Vandenberg on June 26 aboard an Orbital Sciences Pegasus XL rocket, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region in to the sun’s corona using spectrometry and imaging. The IRIS mission will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. The interface region, located between the sun’s visible surface and upper atmosphere, is where most of the sun’s ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth’s climate. For more information, visit http://www.nasa.gov/iris. Photo credit: NASA/Daniel Casper

  14. KSC-2013-2887

    NASA Image and Video Library

    2013-06-24

    VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, mission managers participate in a pre-launch dress rehearsal in the Launch Vehicle Data Center for NASA’s Interface Region Imaging Spectrograph, or IRIS, solar observatory. Scheduled for launch from Vandenberg on June 26 aboard an Orbital Sciences Pegasus XL rocket, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region in to the sun’s corona using spectrometry and imaging. The IRIS mission will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. The interface region, located between the sun’s visible surface and upper atmosphere, is where most of the sun’s ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth’s climate. For more information, visit http://www.nasa.gov/iris. Photo credit: NASA/Daniel Casper

  15. KSC-2013-2886

    NASA Image and Video Library

    2013-06-24

    VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, mission managers participate in a pre-launch dress rehearsal in the Launch Vehicle Data Center for NASA’s Interface Region Imaging Spectrograph, or IRIS, solar observatory. Scheduled for launch from Vandenberg on June 26 aboard an Orbital Sciences Pegasus XL rocket, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region in to the sun’s corona using spectrometry and imaging. The IRIS mission will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. The interface region, located between the sun’s visible surface and upper atmosphere, is where most of the sun’s ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth’s climate. For more information, visit http://www.nasa.gov/iris. Photo credit: NASA/Daniel Casper

  16. KSC-2013-2739

    NASA Image and Video Library

    2013-06-13

    VANDENBERG ABF, Calif. - The launch crew of the Orbital Sciences L-1011 aircraft called "Stargazer" after arrival at Vandenberg Air Force Base for the upcoming launch of the company's Pegasus XL rocket lifting NASA's IRIS solar observatory into orbit. The aircraft will carry the winged rocket to an altitude of 39,000 feet before releasing the Pegasus so its own motors can ignite to send the IRIS into space. The L-1011 is a modified airliner equipped to hold the Pegasus under its body safely. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  17. KSC-2013-2740

    NASA Image and Video Library

    2013-06-13

    VANDENBERG ABF, Calif. - The launch crew of the Orbital Sciences L-1011 aircraft called "Stargazer" after arrival at Vandenberg Air Force Base for the upcoming launch of the company's Pegasus XL rocket lifting NASA's IRIS solar observatory into orbit. The aircraft will carry the winged rocket to an altitude of 39,000 feet before releasing the Pegasus so its own motors can ignite to send the IRIS into space. The L-1011 is a modified airliner equipped to hold the Pegasus under its body safely. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  18. KSC-2013-2738

    NASA Image and Video Library

    2013-06-13

    VANDENBERG ABF, Calif. - The launch crew of the Orbital Sciences L-1011 aircraft called "Stargazer" after arrival at Vandenberg Air Force Base for the upcoming launch of the company's Pegasus XL rocket lifting NASA's IRIS solar observatory into orbit. The aircraft will carry the winged rocket to an altitude of 39,000 feet before releasing the Pegasus so its own motors can ignite to send the IRIS into space. The L-1011 is a modified airliner equipped to hold the Pegasus under its body safely. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  19. KSC-2013-2737

    NASA Image and Video Library

    2013-06-13

    VANDENBERG ABF, Calif. - The launch crew of the Orbital Sciences L-1011 aircraft called "Stargazer" after arrival at Vandenberg Air Force Base for the upcoming launch of the company's Pegasus XL rocket lifting NASA's IRIS solar observatory into orbit. The aircraft will carry the winged rocket to an altitude of 39,000 feet before releasing the Pegasus so its own motors can ignite to send the IRIS into space. The L-1011 is a modified airliner equipped to hold the Pegasus under its body safely. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  20. KSC-2012-5883

    NASA Image and Video Library

    2012-10-09

    VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, technicians install the wing on the Orbital Sciences Corp. Pegasus XL rocket which will launch the Interface Region Imaging Spectrograph, or IRIS, spacecraft. Scheduled for launch from Vandenberg Air Force Base no earlier than Feb. 27, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. For more information, visit http://iris.gsfc.nasa.gov Photo credit: NASA/Randy Beaudoin

  1. KSC-2013-1784

    NASA Image and Video Library

    2013-03-05

    VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, the three stages of the Orbital Sciences Corp. Pegasus XL rocket have been mated in preparation for the launch the Interface Region Imaging Spectrograph, or IRIS, spacecraft. Scheduled for launch from Vandenberg Air Force Base no earlier than April 29, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. For more information, visit http://iris.gsfc.nasa.gov Photo credit: NASA/Randy Beaudoin

  2. KSC-2013-2728

    NASA Image and Video Library

    2013-06-13

    VANDENBERG ABF, Calif. - The Orbital Sciences launch team monitors the Pegasus XL rocket that will lift NASA's IRIS solar observatory into orbit as the rocket and payload are moved from a hangar onto a transporter at Vandenberg Air Force Base. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  3. KSC-2012-5878

    NASA Image and Video Library

    2012-10-09

    VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, technicians prepare to install the wing on the Orbital Sciences Corp. Pegasus XL rocket which will launch the Interface Region Imaging Spectrograph, or IRIS, spacecraft. Scheduled for launch from Vandenberg Air Force Base no earlier than Feb. 27, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. For more information, visit http://iris.gsfc.nasa.gov Photo credit: NASA/Randy Beaudoin

  4. KSC-2013-1785

    NASA Image and Video Library

    2013-03-05

    VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, the three stages of the Orbital Sciences Corp. Pegasus XL rocket have been mated in preparation for the launch the Interface Region Imaging Spectrograph, or IRIS, spacecraft. Scheduled for launch from Vandenberg Air Force Base no earlier than April 29, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. For more information, visit http://iris.gsfc.nasa.gov Photo credit: NASA/Randy Beaudoin

  5. KSC-2012-5881

    NASA Image and Video Library

    2012-10-09

    VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, technicians install the wing on the Orbital Sciences Corp. Pegasus XL rocket which will launch the Interface Region Imaging Spectrograph, or IRIS, spacecraft. Scheduled for launch from Vandenberg Air Force Base no earlier than Feb. 27, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. For more information, visit http://iris.gsfc.nasa.gov Photo credit: NASA/Randy Beaudoin

  6. KSC-2012-5884

    NASA Image and Video Library

    2012-10-09

    VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, technicians install the wing on the Orbital Sciences Corp. Pegasus XL rocket which will launch the Interface Region Imaging Spectrograph, or IRIS, spacecraft. Scheduled for launch from Vandenberg Air Force Base no earlier than Feb. 27, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. For more information, visit http://iris.gsfc.nasa.gov Photo credit: NASA/Randy Beaudoin

  7. KSC-2012-5887

    NASA Image and Video Library

    2012-10-09

    VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, technicians install the aft skirt on the Orbital Sciences Corp. Pegasus XL rocket which will launch the Interface Region Imaging Spectrograph, or IRIS, spacecraft. Scheduled for launch from Vandenberg Air Force Base no earlier than Feb. 27, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. For more information, visit http://iris.gsfc.nasa.gov Photo credit: NASA/Randy Beaudoin

  8. KSC-2013-2725

    NASA Image and Video Library

    2013-06-13

    VANDENBERG ABF, Calif. - The Orbital Sciences launch team monitors the Pegasus XL rocket that will lift NASA's IRIS solar observatory into orbit as the rocket and payload are moved from a hangar onto a transporter at Vandenberg Air Force Base. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  9. KSC-2012-5885

    NASA Image and Video Library

    2012-10-09

    VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, a technician helps install the wing on the Orbital Sciences Corp. Pegasus XL rocket which will launch the Interface Region Imaging Spectrograph, or IRIS, spacecraft. Scheduled for launch from Vandenberg Air Force Base no earlier than Feb. 27, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. For more information, visit http://iris.gsfc.nasa.gov Photo credit: NASA/Randy Beaudoin

  10. KSC-2012-5886

    NASA Image and Video Library

    2012-10-09

    VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, technicians install the wing on the Orbital Sciences Corp. Pegasus XL rocket which will launch the Interface Region Imaging Spectrograph, or IRIS, spacecraft. Scheduled for launch from Vandenberg Air Force Base no earlier than Feb. 27, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. For more information, visit http://iris.gsfc.nasa.gov Photo credit: NASA/Randy Beaudoin

  11. KSC-2013-1786

    NASA Image and Video Library

    2013-03-06

    VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, the three stages of the Orbital Sciences Corp. Pegasus XL rocket have been mated in preparation for the launch the Interface Region Imaging Spectrograph, or IRIS, spacecraft. Scheduled for launch from Vandenberg Air Force Base no earlier than April 29, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. For more information, visit http://iris.gsfc.nasa.gov Photo credit: NASA/Randy Beaudoin

  12. KSC-2012-5889

    NASA Image and Video Library

    2012-10-09

    VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, technicians install the aft skirt on the Orbital Sciences Corp. Pegasus XL rocket which will launch the Interface Region Imaging Spectrograph, or IRIS, spacecraft. Scheduled for launch from Vandenberg Air Force Base no earlier than Feb. 27, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. For more information, visit http://iris.gsfc.nasa.gov Photo credit: NASA/Randy Beaudoin

  13. KSC-2013-2729

    NASA Image and Video Library

    2013-06-13

    VANDENBERG ABF, Calif. - The Orbital Sciences launch team monitors the Pegasus XL rocket that will lift NASA's IRIS solar observatory into orbit as the rocket and payload are moved from a hangar onto a transporter at Vandenberg Air Force Base. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  14. KSC-2012-5890

    NASA Image and Video Library

    2012-10-09

    VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, technicians install the aft skirt on the Orbital Sciences Corp. Pegasus XL rocket which will launch the Interface Region Imaging Spectrograph, or IRIS, spacecraft. Scheduled for launch from Vandenberg Air Force Base no earlier than Feb. 27, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. For more information, visit http://iris.gsfc.nasa.gov Photo credit: NASA/Randy Beaudoin

  15. KSC-2012-5879

    NASA Image and Video Library

    2012-10-09

    VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, technicians prepare to install the wing on the Orbital Sciences Corp. Pegasus XL rocket which will launch the Interface Region Imaging Spectrograph, or IRIS, spacecraft. Scheduled for launch from Vandenberg Air Force Base no earlier than Feb. 27, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. For more information, visit http://iris.gsfc.nasa.gov Photo credit: NASA/Randy Beaudoin

  16. KSC-2013-2203

    NASA Image and Video Library

    2013-04-25

    VANDENBERG AIR FORCE BASE, Calif. -- The Interface Region Imaging Spectrograph, or IRIS, is being readied for mating to the Orbital Sciences Corp. Pegasus XL rocket that will launch the spacecraft. IRIS will be covered in a fairing after it's connected to the nose of the Pegasus to protect the spacecraft from atmospheric heating and stress during launch. Upcoming work includes electrical verification testing. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  17. KSC-2013-2643

    NASA Image and Video Library

    2013-06-10

    VANDENBERG AFB – The Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June is seen after the payload fairing was connected over NASA's IRIS spacecraft. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Tony Vauclin

  18. KSC-2013-2494

    NASA Image and Video Library

    2013-05-29

    VANDENBERG AFB, Calif. – Engineers unwrap NASA's IRIS spacecraft after its connection to the nose of an Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Randy Beaudoin

  19. KSC-2012-5601

    NASA Image and Video Library

    2012-09-25

    Vandenberg Air Force Base, Calif. – At Vandenberg Air Force Base in California, technicians install the avionics shelf on the third stage of the Orbital Sciences Corp. Pegasus XL rocket which will launch the Interface Region Imaging Spectrograph, or IRIS, spacecraft. Scheduled for launch from Vandenberg Air Force Base no earlier than Feb. 27, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. For more information, visit http://iris.gsfc.nasa.gov Photo credit: NASA/Randy Beaudoin

  20. KSC-2013-2493

    NASA Image and Video Library

    2013-05-29

    VANDENBERG AFB, Calif. – Engineers unwrap NASA's IRIS spacecraft after its connection to the nose of an Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Randy Beaudoin

  1. KSC-2012-5602

    NASA Image and Video Library

    2012-09-25

    Vandenberg Air Force Base, Calif. – At Vandenberg Air Force Base in California, technicians install the avionics shelf on the third stage of the Orbital Sciences Corp. Pegasus XL rocket which will launch the Interface Region Imaging Spectrograph, or IRIS, spacecraft. Scheduled for launch from Vandenberg Air Force Base no earlier than Feb. 27, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. For more information, visit http://iris.gsfc.nasa.gov Photo credit: NASA/Randy Beaudoin

  2. KSC-2012-4672

    NASA Image and Video Library

    2012-08-21

    Vandenberg Air Force Base, Calif. – Inside a processing facility at Vandenberg Air Force Base in California, technicians assist as a crane moves the wing closer for a fit check with the Orbital Sciences Pegasus XL launch vehicle. NASA’s Interface Region Imaging Spectrograph, or IRIS, spacecraft will launch aboard the Pegasus XL in late 2012. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and heliosphere, or region around the sun. Photo credit: NASA/Randy Beaudoin

  3. KSC-2012-4677

    NASA Image and Video Library

    2012-08-21

    Vandenberg Air Force Base, Calif. – Inside a processing facility at Vandenberg Air Force Base in California, technicians assist as a crane lowers the wing closer for a fit check with the Orbital Sciences Pegasus XL launch vehicle. NASA’s Interface Region Imaging Spectrograph, or IRIS, spacecraft will launch aboard the Pegasus XL in late 2012. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and heliosphere, or region around the sun. Photo credit: NASA/Randy Beaudoin

  4. KSC-2012-4674

    NASA Image and Video Library

    2012-08-21

    Vandenberg Air Force Base, Calif. – Inside a processing facility at Vandenberg Air Force Base in California, technicians assist as a crane moves the wing closer for a fit check with the Orbital Sciences Pegasus XL launch vehicle. NASA’s Interface Region Imaging Spectrograph, or IRIS, spacecraft will launch aboard the Pegasus XL in late 2012. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and heliosphere, or region around the sun. Photo credit: NASA/Randy Beaudoin

  5. KSC-2012-4673

    NASA Image and Video Library

    2012-08-21

    Vandenberg Air Force Base, Calif. – Inside a processing facility at Vandenberg Air Force Base in California, technicians assist as a crane moves the wing closer for a fit check with the Orbital Sciences Pegasus XL launch vehicle. NASA’s Interface Region Imaging Spectrograph, or IRIS, spacecraft will launch aboard the Pegasus XL in late 2012. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and heliosphere, or region around the sun. Photo credit: NASA/Randy Beaudoin

  6. KSC-2012-4671

    NASA Image and Video Library

    2012-08-21

    Vandenberg Air Force Base, Calif. – Inside a processing facility at Vandenberg Air Force Base in California, technicians prepare the wing for a fit check with the Orbital Sciences Pegasus XL launch vehicle. NASA’s Interface Region Imaging Spectrograph, or IRIS, spacecraft will launch aboard the Pegasus XL in late 2012. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and heliosphere, or region around the sun. Photo credit: NASA/Randy Beaudoin

  7. KSC-2012-4675

    NASA Image and Video Library

    2012-08-21

    Vandenberg Air Force Base, Calif. – Inside a processing facility at Vandenberg Air Force Base in California, technicians assist as a crane lowers the wing closer for a fit check with the Orbital Sciences Pegasus XL launch vehicle. NASA’s Interface Region Imaging Spectrograph, or IRIS, spacecraft will launch aboard the Pegasus XL in late 2012. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and heliosphere, or region around the sun. Photo credit: NASA/Randy Beaudoin

  8. KSC-2012-4676

    NASA Image and Video Library

    2012-08-21

    Vandenberg Air Force Base, Calif. – Inside a processing facility at Vandenberg Air Force Base in California, technicians assist as a crane lowers the wing closer for a fit check with the Orbital Sciences Pegasus XL launch vehicle. NASA’s Interface Region Imaging Spectrograph, or IRIS, spacecraft will launch aboard the Pegasus XL in late 2012. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and heliosphere, or region around the sun. Photo credit: NASA/Randy Beaudoin

  9. KSC-2012-4670

    NASA Image and Video Library

    2012-08-21

    Vandenberg Air Force Base, Calif. – Inside a processing facility at Vandenberg Air Force Base in California, technicians prepare the wing for a fit check with the Orbital Sciences Pegasus XL launch vehicle. NASA’s Interface Region Imaging Spectrograph, or IRIS, spacecraft will launch aboard the Pegasus XL in late 2012. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and heliosphere, or region around the sun. Photo credit: NASA/Randy Beaudoin

  10. KSC-2013-2628

    NASA Image and Video Library

    2013-06-10

    VANDENBERG AFB – Orbital Sciences engineers connect the payload fairing over NASA's IRIS spacecraft. The fairing connects to the nose of the Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Tony Vauclin

  11. KSC-2013-2490

    NASA Image and Video Library

    2013-05-29

    VANDENBERG AFB, Calif. – Engineers unwrap NASA's IRIS spacecraft after its connection to the nose of an Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg no earlier than June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Randy Beaudoin

  12. KSC-2013-2503

    NASA Image and Video Library

    2013-05-30

    VANDENBERG AFB, Calif. – Engineers prepare to install a radial retraction system on NASA's IRIS spacecraft after its connection to the nose of an Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Randy Beaudoin

  13. KSC-2013-2601

    NASA Image and Video Library

    2013-06-10

    VANDENBERG AFB, Calif. – Engineers conduct inspections on NASA's IRIS spacecraft with blacklights before the payload fairing before it is connected. The fairing connects to the nose of the Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Randy Beaudoin

  14. KSC-2013-2642

    NASA Image and Video Library

    2013-06-10

    VANDENBERG AFB – Orbital Sciences team engineers monitor the connection of the payload fairing over NASA's IRIS spacecraft. The fairing connects to the nose of the Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Tony Vauclin

  15. KSC-2013-2640

    NASA Image and Video Library

    2013-06-10

    VANDENBERG AFB – The payload fairing locked in place over NASA's IRIS spacecraft. The fairing connects to the nose of the Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Tony Vauclin

  16. KSC-2013-2618

    NASA Image and Video Library

    2013-06-10

    VANDENBERG AFB – Orbital Sciences team members watch as engineers connect the payload fairing over NASA's IRIS spacecraft. The fairing connects to the nose of the Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Tony Vauclin

  17. KSC-2013-2613

    NASA Image and Video Library

    2013-06-10

    VANDENBERG AFB – Engineers attach the starboard side of the payload fairing into place for NASA's IRIS spacecraft. The fairing connects to the nose of the Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Randy Beaudoin

  18. KSC-2013-2581

    NASA Image and Video Library

    2013-06-05

    VANDENBERG AFB – Engineers move the port side of the payload fairing before it is connected into place for NASA's IRIS spacecraft. The fairing connects to the nose of the Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Randy Beaudoin

  19. KSC-2013-2477

    NASA Image and Video Library

    2013-05-29

    VANDENBERG AFB, Calif. – Engineers prepare to connect NASA's IRIS spacecraft to the nose of an Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg no earlier than June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Randy Beaudoin

  20. KSC-2013-2617

    NASA Image and Video Library

    2013-06-10

    VANDENBERG AFB - Orbital Sciences engineers connect the payload fairing over NASA's IRIS spacecraft. The fairing connects to the nose of the Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Tony Vauclin

  1. KSC-2013-2636

    NASA Image and Video Library

    2013-06-10

    VANDENBERG AFB – Orbital Sciences engineers connect the payload fairing over NASA's IRIS spacecraft. The fairing connects to the nose of the Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Tony Vauclin

  2. KSC-2013-2641

    NASA Image and Video Library

    2013-06-10

    VANDENBERG AFB – Orbital Sciences engineers monitor the connection of the payload fairing over NASA's IRIS spacecraft. The fairing connects to the nose of the Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Tony Vauclin

  3. KSC-2013-2619

    NASA Image and Video Library

    2013-06-10

    VANDENBERG AFB – NASA's IRIS spacecraft before the second half of the payload fairing is installed over it. The fairing connects to the nose of the Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Tony Vauclin

  4. KSC-2013-2480

    NASA Image and Video Library

    2013-05-29

    VANDENBERG AFB, Calif. – Engineers prepare to connect NASA's IRIS spacecraft to the nose of an Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg no earlier than June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Randy Beaudoin

  5. KSC-2013-2635

    NASA Image and Video Library

    2013-06-10

    VANDENBERG AFB – Orbital Sciences engineers connect the payload fairing over NASA's IRIS spacecraft. The fairing connects to the nose of the Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Tony Vauclin

  6. KSC-2013-2481

    NASA Image and Video Library

    2013-05-29

    VANDENBERG AFB, Calif. – Engineers prepare to connect NASA's IRIS spacecraft to the nose of an Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg no earlier than June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Randy Beaudoin

  7. KSC-2013-2633

    NASA Image and Video Library

    2013-06-10

    VANDENBERG AFB – Orbital Sciences team members move the second half of the payload fairing before it is placed over NASA's IRIS spacecraft. The fairing connects to the nose of the Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Tony Vauclin

  8. KSC-2013-2489

    NASA Image and Video Library

    2013-05-29

    VANDENBERG AFB, Calif. – Engineers unwrap NASA's IRIS spacecraft after its connection to the nose of an Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg no earlier than June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Randy Beaudoin

  9. KSC-2013-2639

    NASA Image and Video Library

    2013-06-10

    VANDENBERG AFB – Orbital Sciences engineers connect the payload fairing over NASA's IRIS spacecraft. The fairing connects to the nose of the Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Tony Vauclin

  10. KSC-2013-2504

    NASA Image and Video Library

    2013-05-30

    VANDENBERG AFB, Calif. – Engineers install a radial retraction system on NASA's IRIS spacecraft after its connection to the nose of an Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Randy Beaudoin

  11. KSC-2013-2637

    NASA Image and Video Library

    2013-06-10

    VANDENBERG AFB – Orbital Sciences engineers connect the payload fairing over NASA's IRIS spacecraft. The fairing connects to the nose of the Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Tony Vauclin

  12. KSC-2013-2630

    NASA Image and Video Library

    2013-06-10

    VANDENBERG AFB – Orbital Sciences team members move the second half of the payload fairing before it is placed over NASA's IRIS spacecraft. The fairing connects to the nose of the Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Tony Vauclin

  13. KSC-2013-2602

    NASA Image and Video Library

    2013-06-10

    VANDENBERG AFB, Calif. – Engineers conduct inspections on NASA's IRIS spacecraft with blacklights before the payload fairing before it is connected. The fairing connects to the nose of the Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Randy Beaudoin

  14. KSC-2013-2580

    NASA Image and Video Library

    2013-06-05

    - VANDENBERG AFB – An engineer makes preparations on the starboard side of the payload fairing before it is connected into place for NASA's IRIS spacecraft. The fairing connects to the nose of the Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Randy Beaudoin

  15. KSC-2013-2626

    NASA Image and Video Library

    2013-06-10

    VANDENBERG AFB – Orbital Sciences team members move the second half of the payload fairing before it is placed over NASA's IRIS spacecraft. The fairing connects to the nose of the Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Tony Vauclin

  16. KSC-2013-2616

    NASA Image and Video Library

    2013-06-11

    Orbital Sciences engineers connect the payload fairing over NASA's IRIS spacecraft. The fairing connects to the nose of the Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Tony Vauclin

  17. KSC-2013-2482

    NASA Image and Video Library

    2013-05-29

    VANDENBERG AFB, Calif. – Engineers prepare to connect NASA's IRIS spacecraft to the nose of an Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg no earlier than June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Randy Beaudoin

  18. KSC-2013-2629

    NASA Image and Video Library

    2013-06-10

    VANDENBERG AFB – Orbital Sciences team members move the second half of the payload fairing before it is placed over NASA's IRIS spacecraft. The fairing connects to the nose of the Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg June 26, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Tony Vauclin

  19. KSC-2013-2912

    NASA Image and Video Library

    2013-06-25

    VANDENBERG AIR FORCE BASE, Calif. – Final checkouts are being completed at Vandenberg Air Force Base in California as preparations continue for the launch from the L-1011 carrier aircraft of the Orbital Sciences Corp. Pegasus XL rocket with the Interface Region Imaging Spectrograph, or IRIS, solar observatory. Scheduled for launch from Vandenberg on June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. The IRIS mission will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. The interface region, located between the sun's visible surface and upper atmosphere, is where most of the sun's ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth's climate. For more information, visit http://www.nasa.gov/iris Photo credit: NASA/ Daniel Casper

  20. KSC-2013-2911

    NASA Image and Video Library

    2013-06-25

    VANDENBERG AIR FORCE BASE, Calif. – Final checkouts are being completed at Vandenberg Air Force Base in California as preparations continue for the launch from the L-1011 carrier aircraft of the Orbital Sciences Corp. Pegasus XL rocket with the Interface Region Imaging Spectrograph, or IRIS, solar observatory. Scheduled for launch from Vandenberg on June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. The IRIS mission will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. The interface region, located between the sun's visible surface and upper atmosphere, is where most of the sun's ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth's climate. For more information, visit http://www.nasa.gov/iris Photo credit: NASA/ Daniel Casper

  1. KSC-2013-2205

    NASA Image and Video Library

    2013-04-25

    VANDENBERG AIR FORCE BASE, Calif. -- The Interface Region Imaging Spectrograph, or IRIS, is being readied for mating to the Orbital Sciences Corp. Pegasus XL rocket that will launch the spacecraft. A fairing will be fitted to the nose of the Pegasus to protect the spacecraft from atmospheric heating and stress during launch. Upcoming work includes electrical verification testing. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  2. KSC-2013-2206

    NASA Image and Video Library

    2013-04-25

    VANDENBERG AIR FORCE BASE, Calif. -- The Interface Region Imaging Spectrograph, or IRIS, is being readied for mating to the Orbital Sciences Corp. Pegasus XL rocket that will launch the spacecraft. A fairing will be fitted to the nose of the Pegasus to protect the spacecraft from atmospheric heating and stress during launch. Upcoming work includes electrical verification testing. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  3. KSC-2013-2207

    NASA Image and Video Library

    2013-04-25

    VANDENBERG AIR FORCE BASE, Calif. -- The Interface Region Imaging Spectrograph, or IRIS, is being readied for mating to the Orbital Sciences Corp. Pegasus XL rocket that will launch the spacecraft. A fairing will be fitted to the nose of the Pegasus to protect the spacecraft from atmospheric heating and stress during launch. Upcoming work includes electrical verification testing. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  4. KSC-2013-2745

    NASA Image and Video Library

    2013-06-13

    VANDENBERG ABF, Calif. - The Orbital Sciences L-1011 aircraft called "Stargazer" arrives at Vandenberg Air Force Base for the upcoming launch of the company's Pegasus XL rocket lifting NASA's IRIS solar observatory into orbit. The aircraft will carry the winged rocket to an altitude of 39,000 feet before releasing the Pegasus so its own motors can ignite to send the IRIS into space. The L-1011 is a modified airliner equipped to hold the Pegasus under its body safely. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  5. KSC-2013-2743

    NASA Image and Video Library

    2013-06-13

    VANDENBERG ABF, Calif. - The Orbital Sciences L-1011 aircraft called "Stargazer" arrives at Vandenberg Air Force Base for the upcoming launch of the company's Pegasus XL rocket lifting NASA's IRIS solar observatory into orbit. The aircraft will carry the winged rocket to an altitude of 39,000 feet before releasing the Pegasus so its own motors can ignite to send the IRIS into space. The L-1011 is a modified airliner equipped to hold the Pegasus under its body safely. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  6. KSC-2013-2736

    NASA Image and Video Library

    2013-06-13

    VANDENBERG ABF, Calif. - The cockpit of the Orbital Sciences L-1011 aircraft called "Stargazer" after arrival at Vandenberg Air Force Base for the upcoming launch of the company's Pegasus XL rocket lifting NASA's IRIS solar observatory into orbit. The aircraft will carry the winged rocket to an altitude of 39,000 feet before releasing the Pegasus so its own motors can ignite to send the IRIS into space. The L-1011 is a modified airliner equipped to hold the Pegasus under its body safely. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  7. KSC-2013-2744

    NASA Image and Video Library

    2013-06-13

    VANDENBERG ABF, Calif. – One of the portable control trailers is set up at Vandenberg Air Force Base for the upcoming launch of an Orbital Sciences Pegasus XL rocket lifting NASA's IRIS solar observatory into orbit. The aircraft will carry the winged rocket to an altitude of 39,000 feet before releasing the Pegasus so its own motors can ignite to send the IRIS into space. The L-1011 is a modified airliner equipped to hold the Pegasus under its body safely. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  8. KSC-2013-2735

    NASA Image and Video Library

    2013-06-13

    VANDENBERG ABF, Calif. - The Orbital Sciences L-1011 aircraft called "Stargazer" arrives at Vandenberg Air Force Base for the upcoming launch of the company's Pegasus XL rocket lifting NASA's IRIS solar observatory into orbit. The aircraft will carry the winged rocket to an altitude of 39,000 feet before releasing the Pegasus so its own motors can ignite to send the IRIS into space. The L-1011 is a modified airliner equipped to hold the Pegasus under its body safely. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  9. KSC-2013-2910

    NASA Image and Video Library

    2013-06-25

    VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, NASA hosted a prelaunch mission briefing on the Interface Region Imaging Spectrograph, or IRIS, solar observatory scheduled to launch on a Pegasus XL rocket. Participating in the news conference are George Diller, NASA Public Affairs, Dr. S. Pete Worden, director of NASA's Ames Research Center in Calif., Jeffrey Newmark, IRIS Program scientist at NASA Headquarters in Washington D.C., and Alan Title, IRIS principal investigator with Lockheed Martin. Scheduled for launch from Vandenberg on June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. The IRIS mission will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. The interface region, located between the sun's visible surface and upper atmosphere, is where most of the sun's ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth's climate. For more information, visit http://www.nasa.gov/iris Photo credit: NASA/ Daniel Casper

  10. KSC-2013-2730

    NASA Image and Video Library

    2013-06-13

    VANDENBERG ABF, Calif. - The Orbital Sciences Pegasus XL rocket that will lift NASA's IRIS solar observatory into orbit is moved from a hangar onto a transporter at Vandenberg Air Force Base. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  11. KSC-2013-2731

    NASA Image and Video Library

    2013-06-13

    VANDENBERG ABF, Calif. - The Orbital Sciences Pegasus XL rocket that will lift NASA's IRIS solar observatory into orbit is moved from a hangar onto a transporter at Vandenberg Air Force Base. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  12. KSC-2013-2726

    NASA Image and Video Library

    2013-06-13

    VANDENBERG ABF, Calif. - The Orbital Sciences Pegasus XL rocket that will lift NASA's IRIS solar observatory into orbit is moved from a hangar onto a transporter at Vandenberg Air Force Base. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  13. KSC-2013-2733

    NASA Image and Video Library

    2013-06-13

    VANDENBERG ABF, Calif. - The Orbital Sciences Pegasus XL rocket that will lift NASA's IRIS solar observatory into orbit is moved from a hangar onto a transporter at Vandenberg Air Force Base. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  14. KSC-2013-2734

    NASA Image and Video Library

    2013-06-13

    VANDENBERG ABF, Calif. - The Orbital Sciences Pegasus XL rocket that will lift NASA's IRIS solar observatory into orbit is moved from a hangar onto a transporter at Vandenberg Air Force Base. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  15. KSC-2013-2732

    NASA Image and Video Library

    2013-06-13

    VANDENBERG ABF, Calif. - The Orbital Sciences Pegasus XL rocket that will lift NASA's IRIS solar observatory into orbit is moved from a hangar onto a transporter at Vandenberg Air Force Base. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  16. KSC-2013-2669

    NASA Image and Video Library

    2013-06-11

    VANDENBERG ABF, Calif. - The Orbital Sciences Pegasus XL rocket that will lift NASA's IRIS solar observatory into orbit in June is seen in a hangar at Vandenberg Air Force Base. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  17. KSC-2013-2668

    NASA Image and Video Library

    2013-06-11

    VANDENBERG ABF, Calif. - The Orbital Sciences Pegasus XL rocket that will lift NASA's IRIS solar observatory into orbit in June is seen in a hangar at Vandenberg Air Force Base. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  18. KSC-2013-2666

    NASA Image and Video Library

    2013-06-11

    VANDENBERG ABF, Calif. - The Orbital Sciences Pegasus XL rocket that will lift NASA's IRIS solar observatory into orbit in June is seen in a hangar at Vandenberg Air Force Base. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  19. KSC-2013-2665

    NASA Image and Video Library

    2013-06-11

    VANDENBERG ABF, Calif. - The Orbital Sciences Pegasus XL rocket that will lift NASA's IRIS solar observatory into orbit in June is seen in a hangar at Vandenberg Air Force Base. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  20. KSC-2013-2667

    NASA Image and Video Library

    2013-06-11

    VANDENBERG ABF, Calif. - The Orbital Sciences Pegasus XL rocket that will lift NASA's IRIS solar observatory into orbit in June is seen in a hangar at Vandenberg Air Force Base. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  1. KSC-2013-2727

    NASA Image and Video Library

    2013-06-13

    VANDENBERG ABF, Calif. - The Orbital Sciences Pegasus XL rocket that will lift NASA's IRIS solar observatory into orbit is moved from a hangar onto a transporter at Vandenberg Air Force Base. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  2. KSC-2013-2909

    NASA Image and Video Library

    2013-06-25

    VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, NASA hosted a prelaunch news conference on the Interface Region Imaging Spectrograph, or IRIS, solar observatory scheduled to launch on a Pegasus XL rocket. Participating in the news conference are George Diller, NASA Public Affairs, Geoffrey Yoder, deputy associate administrator for the Programs, Science Mission Directorate at NASA Headquarters in Washington, D.C., Tim Dunn, NASA launch director/NASA Launch Manager at the Kennedy Space Center in Florida, Bryan Baldwin, Pegasus launch vehicle program director for Orbital Sciences Corp. of Dulles, Va., Gary Kushner, IRIS project manager for Lockheed Martin's Solar and Astrophysics Laboratory in Palo Alto, Calif., and First Lt. Jennifer Kelley, launch weather officer for the U.S. Air Force 30th Operations Support Squadron at Vandenberg. Scheduled for launch from Vandenberg on June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. The IRIS mission will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. The interface region, located between the sun's visible surface and upper atmosphere, is where most of the sun's ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth's climate. For more information, visit http://www.nasa.gov/iris Photo credit: NASA/ Daniel Casper

  3. KSC-2013-2742

    NASA Image and Video Library

    2013-06-13

    VANDENBERG ABF, Calif. – A look through the inside of the fuselage of the Orbital Sciences L-1011 aircraft called "Stargazer" after arrival at Vandenberg Air Force Base for the upcoming launch of the company's Pegasus XL rocket lifting NASA's IRIS solar observatory into orbit. The aircraft will carry the winged rocket to an altitude of 39,000 feet before releasing the Pegasus so its own motors can ignite to send the IRIS into space. The L-1011 is a modified airliner equipped to hold the Pegasus under its body safely. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  4. KSC-2013-2741

    NASA Image and Video Library

    2013-06-13

    VANDENBERG ABF, Calif. – A look through the inside of the fuselage of the Orbital Sciences L-1011 aircraft called "Stargazer" after arrival at Vandenberg Air Force Base for the upcoming launch of the company's Pegasus XL rocket lifting NASA's IRIS solar observatory into orbit. The aircraft will carry the winged rocket to an altitude of 39,000 feet before releasing the Pegasus so its own motors can ignite to send the IRIS into space. The L-1011 is a modified airliner equipped to hold the Pegasus under its body safely. IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  5. KSC-2013-2627

    NASA Image and Video Library

    2013-06-10

    VANDENBERG AFB – Detail of the Orbital Sciences Pegasus XL rocket that will lift NASA's IRIS solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Tony Vauclin

  6. KSC-2013-2620

    NASA Image and Video Library

    2013-06-10

    VANDENBERG AFB – Detail of the Orbital Sciences Pegasus XL rocket that will lift NASA's IRIS solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Tony Vauclin

  7. KSC-2013-2625

    NASA Image and Video Library

    2013-06-10

    VANDENBERG AFB – Detail of the Orbital Sciences Pegasus XL rocket that will lift NASA's IRIS solar observatory into orbit in June. The work is taking place in a hangar at Vandenberg Air Force Base where IRIS, short for Interface Region Imaging Spectrograph, is being prepared for launch from Vandenberg June 26. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: NASA/Tony Vauclin

  8. KSC-2012-2821

    NASA Image and Video Library

    2012-05-11

    Vandenberg Air Force Base, Calif. – A truck carrying the third stage of the Orbital Sciences Pegasus XL rocket arrives at Vandenberg Air Force Base in California. NASA’s Interface Region Imaging Spectrograph, or IRIS, spacecraft will launch aboard the Pegasus XL in late 2012. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and heliosphere, or region around the sun. Photo credit: NASA/Randy Beaudoin

  9. KSC-2012-2820

    NASA Image and Video Library

    2012-05-11

    Vandenberg Air Force Base, Calif. – A truck carrying all three stages of the Orbital Sciences Pegasus XL rocket arrives at Vandenberg Air Force Base in California. NASA’s Interface Region Imaging Spectrograph, or IRIS, spacecraft will launch aboard the Pegasus XL in late 2012. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and heliosphere, or region around the sun. Photo credit: NASA/Randy Beaudoin

  10. KSC-2012-2826

    NASA Image and Video Library

    2012-05-11

    Vandenberg Air Force Base, Calif. – A truck carrying all three stages of the Orbital Sciences Pegasus XL rocket arrives at Vandenberg Air Force Base in California. NASA’s Interface Region Imaging Spectrograph, or IRIS, spacecraft will launch aboard the Pegasus XL in late 2012. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and heliosphere, or region around the sun. Photo credit: NASA/Randy Beaudoin

  11. Preparing NASA's Next Solar Satellite for Launch

    NASA Image and Video Library

    2017-12-08

    Orbital Sciences team members move the second half of the payload fairing before it is placed over NASA's IRIS (Interface Region Imaging Spectrograph) spacecraft. The fairing connects to the nose of the Orbital Sciences Pegasus XL rocket that will lift the solar observatory into orbit. The work is taking place in a hangar at Vandenberg Air Force Base, where IRIS is being prepared for launch on a Pegasus XL rocket. Scheduled for launch from Vandenberg on June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun's corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. High res file available here: 1.usa.gov/11yal3w Photo Credit: NASA/Tony Vauclin 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

  12. KSC-2012-2824

    NASA Image and Video Library

    2012-05-11

    Vandenberg Air Force Base, Calif. – Inside a hangar at Vandenberg Air Force Base in California, technicians offload the second stage of the Orbital Sciences Pegasus XL rocket from the truck in which it was transported. NASA’s Interface Region Imaging Spectrograph, or IRIS, spacecraft will launch aboard the Pegasus XL in late 2012. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and heliosphere, or region around the sun. Photo credit: NASA/Randy Beaudoin

  13. KSC-2012-2828

    NASA Image and Video Library

    2012-05-11

    Vandenberg Air Force Base, Calif. – At Vandenberg Air Force Base in California, technicians prepare to offload the first stage of the Orbital Sciences Pegasus XL rocket from the truck in which it was transported. NASA’s Interface Region Imaging Spectrograph, or IRIS, spacecraft will launch aboard the Pegasus XL in late 2012. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and heliosphere, or region around the sun. Photo credit: NASA/Randy Beaudoin

  14. KSC-2012-2827

    NASA Image and Video Library

    2012-05-11

    Vandenberg Air Force Base, Calif. – At Vandenberg Air Force Base in California, technicians prepare to offload the first stage of the Orbital Sciences Pegasus XL rocket from the truck in which it was transported. NASA’s Interface Region Imaging Spectrograph, or IRIS, spacecraft will launch aboard the Pegasus XL in late 2012. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and heliosphere, or region around the sun. Photo credit: NASA/Randy Beaudoin

  15. KSC-2012-2825

    NASA Image and Video Library

    2012-05-11

    Vandenberg Air Force Base, Calif. – Inside a hangar at Vandenberg Air Force Base in California, technicians offload the second stage of the Orbital Sciences Pegasus XL rocket from the truck in which it was transported. NASA’s Interface Region Imaging Spectrograph, or IRIS, spacecraft will launch aboard the Pegasus XL in late 2012. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and heliosphere, or region around the sun. Photo credit: NASA/Randy Beaudoin

  16. KSC-2012-2822

    NASA Image and Video Library

    2012-05-11

    Vandenberg Air Force Base, Calif. – Inside a hangar at Vandenberg Air Force Base in California, technicians prepare to offload the third stage of the Orbital Sciences Pegasus XL rocket from the truck in which it was transported. NASA’s Interface Region Imaging Spectrograph, or IRIS, spacecraft will launch aboard the Pegasus XL in late 2012. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and heliosphere, or region around the sun. Photo credit: NASA/Randy Beaudoin

  17. KSC-2012-2831

    NASA Image and Video Library

    2012-05-11

    Vandenberg Air Force Base, Calif. – At Vandenberg Air Force Base in California, technicians offload the first stage of the Orbital Sciences Pegasus XL rocket from the truck in which it was transported. NASA’s Interface Region Imaging Spectrograph, or IRIS, spacecraft will launch aboard the Pegasus XL in late 2012. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and heliosphere, or region around the sun. Photo credit: NASA/Randy Beaudoin

  18. KSC-2012-2829

    NASA Image and Video Library

    2012-05-11

    Vandenberg Air Force Base, Calif. – At Vandenberg Air Force Base in California, technicians prepare to offload the first stage of the Orbital Sciences Pegasus XL rocket from the truck in which it was transported. NASA’s Interface Region Imaging Spectrograph, or IRIS, spacecraft will launch aboard the Pegasus XL in late 2012. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and heliosphere, or region around the sun. Photo credit: NASA/Randy Beaudoin

  19. KSC-2012-2830

    NASA Image and Video Library

    2012-05-11

    Vandenberg Air Force Base, Calif. – At Vandenberg Air Force Base in California, technicians offload the first stage of the Orbital Sciences Pegasus XL rocket from the truck in which it was transported. NASA’s Interface Region Imaging Spectrograph, or IRIS, spacecraft will launch aboard the Pegasus XL in late 2012. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and heliosphere, or region around the sun. Photo credit: NASA/Randy Beaudoin

  20. KSC-2012-2823

    NASA Image and Video Library

    2012-05-11

    Vandenberg Air Force Base, Calif. – Inside a hangar at Vandenberg Air Force Base in California, technicians prepare to offload the third stage of the Orbital Sciences Pegasus XL rocket from the truck in which it was transported. NASA’s Interface Region Imaging Spectrograph, or IRIS, spacecraft will launch aboard the Pegasus XL in late 2012. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and heliosphere, or region around the sun. Photo credit: NASA/Randy Beaudoin

  1. KSC-2013-2204

    NASA Image and Video Library

    2013-04-25

    VANDENBERG AIR FORCE BASE, Calif. -- Half of the fairing that will be fitted to the nose of the Orbital Sciences Corp. Pegasus XL rocket is ready for its installation around the Interface Region Imaging Spectrograph, or IRIS, spacecraft. The fairing will protect the spacecraft from atmospheric heating and stress during launch. IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. IRIS fills a crucial gap in our ability to advance studies of the sun-to-Earth connection by tracing the flow of energy and plasma through the foundation of the corona and the region around the sun known as the heliosphere. Photo credit: VAFB/Randy Beaudoin

  2. KSC-2013-2828

    NASA Image and Video Library

    2013-06-19

    VANDENBERG AIR FORCE BASE, Calif. – Technicians and engineers at Vandenberg Air Force Base in California mate the Pegasus XL rocket with the Interface Region Imaging Spectrograph, or IRIS, solar observatory to the Orbital Sciences L-1011 carrier aircraft. Scheduled for launch from Vandenberg on June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. The IRIS mission will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. The interface region, located between the sun's visible surface and upper atmosphere, is where most of the sun's ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth's climate. For more information, visit http://www.nasa.gov/iris Photo credit: NASA/Randy Beaudoin

  3. KSC-2013-2825

    NASA Image and Video Library

    2013-06-19

    VANDENBERG AIR FORCE BASE, Calif. – Technicians and engineers at Vandenberg Air Force Base in California mate the Pegasus XL rocket with the Interface Region Imaging Spectrograph, or IRIS, solar observatory to the Orbital Sciences L-1011 carrier aircraft. Scheduled for launch from Vandenberg on June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. The IRIS mission will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. The interface region, located between the sun's visible surface and upper atmosphere, is where most of the sun's ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth's climate. For more information, visit http://www.nasa.gov/iris Photo credit: NASA/Randy Beaudoin

  4. KSC-2013-2831

    NASA Image and Video Library

    2013-06-19

    VANDENBERG AIR FORCE BASE, Calif. – Technicians and engineers at Vandenberg Air Force Base in California mate the Pegasus XL rocket with the Interface Region Imaging Spectrograph, or IRIS, solar observatory to the Orbital Sciences L-1011 carrier aircraft. Scheduled for launch from Vandenberg on June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. The IRIS mission will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. The interface region, located between the sun's visible surface and upper atmosphere, is where most of the sun's ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth's climate. For more information, visit http://www.nasa.gov/iris Photo credit: NASA/Randy Beaudoin

  5. KSC-2013-2830

    NASA Image and Video Library

    2013-06-19

    VANDENBERG AIR FORCE BASE, Calif. – Technicians and engineers at Vandenberg Air Force Base in California mate the Pegasus XL rocket with the Interface Region Imaging Spectrograph, or IRIS, solar observatory to the Orbital Sciences L-1011 carrier aircraft. Scheduled for launch from Vandenberg on June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. The IRIS mission will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. The interface region, located between the sun's visible surface and upper atmosphere, is where most of the sun's ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth's climate. For more information, visit http://www.nasa.gov/iris Photo credit: NASA/Randy Beaudoin

  6. KSC-2013-2832

    NASA Image and Video Library

    2013-06-19

    VANDENBERG AIR FORCE BASE, Calif. – Technicians and engineers at Vandenberg Air Force Base in California mate the Pegasus XL rocket with the Interface Region Imaging Spectrograph, or IRIS, solar observatory to the Orbital Sciences L-1011 carrier aircraft. Scheduled for launch from Vandenberg on June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. The IRIS mission will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. The interface region, located between the sun's visible surface and upper atmosphere, is where most of the sun's ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth's climate. For more information, visit http://www.nasa.gov/iris Photo credit: NASA/Randy Beaudoin

  7. KSC-2013-2833

    NASA Image and Video Library

    2013-06-19

    VANDENBERG AIR FORCE BASE, Calif. – Technicians and engineers at Vandenberg Air Force Base in California mate the Pegasus XL rocket with the Interface Region Imaging Spectrograph, or IRIS, solar observatory to the Orbital Sciences L-1011 carrier aircraft. Scheduled for launch from Vandenberg on June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. The IRIS mission will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. The interface region, located between the sun's visible surface and upper atmosphere, is where most of the sun's ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth's climate. For more information, visit http://www.nasa.gov/iris Photo credit: NASA/Randy Beaudoin

  8. KSC-2013-2824

    NASA Image and Video Library

    2013-06-19

    VANDENBERG AIR FORCE BASE, Calif. – Technicians and engineers at Vandenberg Air Force Base in California mate the Pegasus XL rocket with the Interface Region Imaging Spectrograph, or IRIS, solar observatory to the Orbital Sciences L-1011 carrier aircraft. Scheduled for launch from Vandenberg on June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. The IRIS mission will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. The interface region, located between the sun's visible surface and upper atmosphere, is where most of the sun's ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth's climate. For more information, visit http://www.nasa.gov/iris Photo credit: NASA/Randy Beaudoin

  9. KSC-2013-2827

    NASA Image and Video Library

    2013-06-19

    VANDENBERG AIR FORCE BASE, Calif. – Technicians and engineers at Vandenberg Air Force Base in California mate the Pegasus XL rocket with the Interface Region Imaging Spectrograph, or IRIS, solar observatory to the Orbital Sciences L-1011 carrier aircraft. Scheduled for launch from Vandenberg on June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. The IRIS mission will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. The interface region, located between the sun's visible surface and upper atmosphere, is where most of the sun's ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth's climate. For more information, visit http://www.nasa.gov/iris Photo credit: NASA/Randy Beaudoin

  10. KSC-2013-2826

    NASA Image and Video Library

    2013-06-19

    VANDENBERG AIR FORCE BASE, Calif. – Technicians and engineers at Vandenberg Air Force Base in California mate the Pegasus XL rocket with the Interface Region Imaging Spectrograph, or IRIS, solar observatory to the Orbital Sciences L-1011 carrier aircraft. Scheduled for launch from Vandenberg on June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. The IRIS mission will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. The interface region, located between the sun's visible surface and upper atmosphere, is where most of the sun's ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth's climate. For more information, visit http://www.nasa.gov/iris Photo credit: NASA/Randy Beaudoin

  11. KSC-2013-2829

    NASA Image and Video Library

    2013-06-19

    VANDENBERG AIR FORCE BASE, Calif. – Technicians and engineers at Vandenberg Air Force Base in California mate the Pegasus XL rocket with the Interface Region Imaging Spectrograph, or IRIS, solar observatory to the Orbital Sciences L-1011 carrier aircraft. Scheduled for launch from Vandenberg on June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. The IRIS mission will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. The interface region, located between the sun's visible surface and upper atmosphere, is where most of the sun's ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth's climate. For more information, visit http://www.nasa.gov/iris Photo credit: NASA/Randy Beaudoin

  12. KSC-2013-2834

    NASA Image and Video Library

    2013-06-19

    VANDENBERG AIR FORCE BASE, Calif. – Technicians and engineers at Vandenberg Air Force Base in California mate the Pegasus XL rocket with the Interface Region Imaging Spectrograph, or IRIS, solar observatory to the Orbital Sciences L-1011 carrier aircraft. Scheduled for launch from Vandenberg on June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. The IRIS mission will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. The interface region, located between the sun's visible surface and upper atmosphere, is where most of the sun's ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth's climate. For more information, visit http://www.nasa.gov/iris Photo credit: NASA/Randy Beaudoin

  13. The infrared imaging spectrograph (IRIS) for TMT: overview of innovative science programs

    NASA Astrophysics Data System (ADS)

    Wright, Shelley A.; Larkin, James E.; Moore, Anna M.; Do, Tuan; Simard, Luc; Adamkovics, Maté; Armus, Lee; Barth, Aaron J.; Barton, Elizabeth; Boyce, Hope; Cooke, Jeffrey; Cote, Patrick; Davidge, Timothy; Ellerbroek, Brent; Ghez, Andrea M.; Liu, Michael C.; Lu, Jessica R.; Macintosh, Bruce A.; Mao, Shude; Marois, Christian; Schoeck, Matthias; Suzuki, Ryuji; Tan, Jonathan C.; Treu, Tommaso; Wang, Lianqi; Weiss, Jason

    2014-07-01

    IRIS (InfraRed Imaging Spectrograph) is a first light near-infrared diffraction limited imager and integral field spectrograph being designed for the future Thirty Meter Telescope (TMT). IRIS is optimized to perform astronomical studies across a significant fraction of cosmic time, from our Solar System to distant newly formed galaxies (Barton et al. [1]). We present a selection of the innovative science cases that are unique to IRIS in the era of upcoming space and ground-based telescopes. We focus on integral field spectroscopy of directly imaged exoplanet atmospheres, probing fundamental physics in the Galactic Center, measuring 104 to 1010 M supermassive black hole masses, resolved spectroscopy of young star-forming galaxies (1 < z < 5) and first light galaxies (6 < z < 12), and resolved spectroscopy of strong gravitational lensed sources to measure dark matter substructure. For each of these science cases we use the IRIS simulator (Wright et al. [2], Do et al. [3]) to explore IRIS capabilities. To highlight the unique IRIS capabilities, we also update the point and resolved source sensitivities for the integral field spectrograph (IFS) in all five broadband filters (Z, Y, J, H, K) for the finest spatial scale of 0.004" per spaxel. We briefly discuss future development plans for the data reduction pipeline and quicklook software for the IRIS instrument suite.

  14. KSC-2013-2939

    NASA Image and Video Library

    2013-06-27

    VANDENBERG AIR FORCE BASE, Calif. – The Orbital Sciences L-1011 aircraft takes off from Vandenberg Air Force Base in California at 9:30 p.m. EDT, headed over the Pacific Ocean to release the Pegasus XL rocket carrying NASA's Interface Region Imaging Spectrograph, or IRIS, solar observatory. Release of the rocket from under the wing of the aircraft is scheduled for 10:27 p.m. EDT. IRIS will open a new window of discovery using spectrometry and imaging to trace the flow of energy and plasma through the chromospheres and transition region into the sun’s corona. The spacecraft will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. This interface region, located between the sun's visible surface and its upper atmosphere, is where most of its ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth's climate. NASA's Launch Services Program at the agency's Kennedy Space Center in Florida is managing the countdown and launch. For more information, visit http://www.nasa.gov/iris. Photo credit: NASA/Daniel Casper

  15. KSC-2013-2835

    NASA Image and Video Library

    2013-06-19

    VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, the Pegasus XL rocket with the attached Interface Region Imaging Spectrograph IRIS solar observatory rolled out of the hangar on its transporter to the runway at Vandenberg. There, the rocket and spacecraft were mated with the Orbital Sciences L-1011 carrier aircraft. Scheduled for launch from Vandenberg on June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. The IRIS mission will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. The interface region, located between the sun's visible surface and upper atmosphere, is where most of the sun's ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth's climate. For more information, visit http://www.nasa.gov/iris Photo credit: NASA/Randy Beaudoin

  16. KSC-2013-2839

    NASA Image and Video Library

    2013-06-19

    VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, the Pegasus XL rocket with the attached Interface Region Imaging Spectrograph IRIS solar observatory rolled out of the hangar on its transporter to the runway at Vandenberg. There, the rocket and spacecraft were mated with the Orbital Sciences L-1011 carrier aircraft. Scheduled for launch from Vandenberg on June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. The IRIS mission will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. The interface region, located between the sun's visible surface and upper atmosphere, is where most of the sun's ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth's climate. For more information, visit http://www.nasa.gov/iris Photo credit: NASA/Randy Beaudoin

  17. KSC-2013-2837

    NASA Image and Video Library

    2013-06-19

    VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, the Pegasus XL rocket with the attached Interface Region Imaging Spectrograph IRIS solar observatory rolled out of the hangar on its transporter to the runway at Vandenberg. There, the rocket and spacecraft were mated with the Orbital Sciences L-1011 carrier aircraft. Scheduled for launch from Vandenberg on June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. The IRIS mission will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. The interface region, located between the sun's visible surface and upper atmosphere, is where most of the sun's ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth's climate. For more information, visit http://www.nasa.gov/iris Photo credit: NASA/Randy Beaudoin

  18. KSC-2013-2840

    NASA Image and Video Library

    2013-06-19

    VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, the Pegasus XL rocket with the attached Interface Region Imaging Spectrograph IRIS solar observatory rolled out of the hangar on its transporter to the runway at Vandenberg. There, the rocket and spacecraft were mated with the Orbital Sciences L-1011 carrier aircraft. Scheduled for launch from Vandenberg on June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. The IRIS mission will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. The interface region, located between the sun's visible surface and upper atmosphere, is where most of the sun's ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth's climate. For more information, visit http://www.nasa.gov/iris Photo credit: NASA/Randy Beaudoin

  19. KSC-2013-2843

    NASA Image and Video Library

    2013-06-19

    VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, the Pegasus XL rocket with the attached Interface Region Imaging Spectrograph IRIS solar observatory rolled out of the hangar on its transporter to the runway at Vandenberg. There, the rocket and spacecraft were mated with the Orbital Sciences L-1011 carrier aircraft. Scheduled for launch from Vandenberg on June 26, 2013, IRIS will open a new window of discovery by tracing the flow of energy and plasma through the chromospheres and transition region into the sun’s corona using spectrometry and imaging. The IRIS mission will observe how solar material moves, gathers energy and heats up as it travels through a largely unexplored region of the solar atmosphere. The interface region, located between the sun's visible surface and upper atmosphere, is where most of the sun's ultraviolet emission is generated. These emissions impact the near-Earth space environment and Earth's climate. For more information, visit http://www.nasa.gov/iris Photo credit: NASA/Randy Beaudoin

  20. The infrared imaging spectrograph (IRIS) for TMT: latest science cases and simulations

    NASA Astrophysics Data System (ADS)

    Wright, Shelley A.; Walth, Gregory; Do, Tuan; Marshall, Daniel; Larkin, James E.; Moore, Anna M.; Adamkovics, Mate; Andersen, David; Armus, Lee; Barth, Aaron; Cote, Patrick; Cooke, Jeff; Chisholm, Eric M.; Davidge, Timothy; Dunn, Jennifer S.; Dumas, Christophe; Ellerbroek, Brent L.; Ghez, Andrea M.; Hao, Lei; Hayano, Yutaka; Liu, Michael; Lopez-Rodriguez, Enrique; Lu, Jessica R.; Mao, Shude; Marois, Christian; Pandey, Shashi B.; Phillips, Andrew C.; Schoeck, Matthias; Subramaniam, Annapurni; Subramanian, Smitha; Suzuki, Ryuji; Tan, Jonathan C.; Terai, Tsuyoshi; Treu, Tommaso; Simard, Luc; Weiss, Jason L.; Wincentsen, James; Wong, Michael; Zhang, Kai

    2016-07-01

    The Thirty Meter Telescope (TMT) first light instrument IRIS (Infrared Imaging Spectrograph) will complete its preliminary design phase in 2016. The IRIS instrument design includes a near-infrared (0.85 - 2.4 micron) integral field spectrograph (IFS) and imager that are able to conduct simultaneous diffraction-limited observations behind the advanced adaptive optics system NFIRAOS. The IRIS science cases have continued to be developed and new science studies have been investigated to aid in technical performance and design requirements. In this development phase, the IRIS science team has paid particular attention to the selection of filters, gratings, sensitivities of the entire system, and science cases that will benefit from the parallel mode of the IFS and imaging camera. We present new science cases for IRIS using the latest end-to-end data simulator on the following topics: Solar System bodies, the Galactic center, active galactic nuclei (AGN), and distant gravitationally-lensed galaxies. We then briefly discuss the necessity of an advanced data management system and data reduction pipeline.

  1. On-instrument wavefront sensor design for the TMT infrared imaging spectrograph (IRIS) update

    NASA Astrophysics Data System (ADS)

    Dunn, Jennifer; Reshetov, Vladimir; Atwood, Jenny; Pazder, John; Wooff, Bob; Loop, David; Saddlemyer, Leslie; Moore, Anna M.; Larkin, James E.

    2014-08-01

    The first light instrument on the Thirty Meter Telescope (TMT) project will be the InfraRed Imaging Spectrograph (IRIS). IRIS will be mounted on a bottom port of the facility AO instrument NFIRAOS. IRIS will report guiding information to the NFIRAOS through the On-Instrument Wavefront Sensor (OIWFS) that is part of IRIS. This will be in a self-contained compartment of IRIS and will provide three deployable wavefront sensor probe arms. This entire unit will be rotated to provide field de-rotation. Currently in our preliminary design stage our efforts have included: prototyping of the probe arm to determine the accuracy of this critical component, handling cart design and reviewing different types of glass for the atmospheric dispersion.

  2. NASA's IRIS Observed a Gigantic Eruption on the Sun!

    NASA Image and Video Library

    2014-05-30

    A coronal mass ejection, or CME, surged off the side of the sun on May 9, 2014, and NASA's newest solar observatory caught it in extraordinary detail. This was the first CME observed by the Interface Region Imaging Spectrograph, or IRIS, which launched in June 2013 to peer into the lowest levels of the sun's atmosphere with better resolution than ever before. Watch the movie to see how a curtain of solar material erupts outward at speeds of 1.5 million miles per hour. Read more: 1.usa.gov/1kp7O4F Credit: NASA's Goddard Space Flight Center 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

  3. Simultaneous observations of Ellerman bombs by NST and IRIS

    NASA Astrophysics Data System (ADS)

    Kim, Y. H.; Yurchyshyn, V.; Cho, I. H.; Lee, J.; Park, Y. D.; Yang, H.; Ahn, K.; Goode, P.

    2015-12-01

    In this study, we present the simultaneous observations of Ellerman bombs made by New Solar Telescope (NST) of Big Bear Solar Observatory (BBSO) and Interface Region Imaging Spectrograph (IRIS) in space. The data obtained during joint NST-IRIS observations on 30 and 31 in July 2014. We observed two representative events on both days. The first one was a relatively weak Ellerman bomb occurred around 19:20 UT on 30 July 2014. IRIS observed this event by sit-and-stare mode thus we analyzed high cadence spectral data and slit-jaw data simultaneously. We found that this event was a hot explosion that occurred by magnetic reconnection in the lower atmosphere of the Sun. The second event was quite strong Ellerman bomb (20:20 UT on 31 July 2014) that is well observed by NST FISS (Fast Imaging Solar Spectrograph), while there was no IRIS spectral data. We had IRIS slit-jaw data only. The Ellerman bomb was clearly coincident with the IRIS brightening at the same location. Since the Ellerman bombs are usually believed to occur in the photosphere with no coronal emission, it should be explained its higher atmospheric emission in IRIS data. We will present the result of simultaneous observations by IRIS and NST instruments and discuss physical connection between Ellerman bombs and IRIS brightenings.

  4. A First for NASA's IRIS: Observing a Gigantic Eruption of Solar Material

    NASA Image and Video Library

    2014-05-30

    Watch a video from this event here: www.flickr.com/photos/gsfc/14118958800/ A coronal mass ejection, or CME, surged off the side of the sun on May 9, 2014, and NASA's newest solar observatory caught it in extraordinary detail. This was the first CME observed by the Interface Region Imaging Spectrograph, or IRIS, which launched in June 2013 to peer into the lowest levels of the sun's atmosphere with better resolution than ever before. Watch the movie to see how a curtain of solar material erupts outward at speeds of 1.5 million miles per hour. Read more: 1.usa.gov/1kp7O4F 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

  5. Observational evidence for Alfven waves in the solar atmosphere (Invited)

    NASA Astrophysics Data System (ADS)

    De Pontieu, B.

    2013-12-01

    Alfven waves have long been suspected of playing an important role in both heating the corona and accelerating the solar wind. Recently, more and more observational evidence for the presence of such waves has been reported in both the corona and the lower solar atmosphere. I will review observations of the properties and presence of Alfven waves from CoMP, Hinode, AIA and ground-based telescopes in both coronal lines and the lower solar atmosphere. I will discuss our current understanding of the importance of these waves for the energy balance of the corona. I will also present initial results of the Interface Region Imaging Spectrograph (IRIS) which was launched in June 2013 and obtains images and spectra in both the far and near ultraviolet.

  6. The infrared imaging spectrograph (IRIS) for TMT: reflective ruled diffraction grating performance testing and discussion

    NASA Astrophysics Data System (ADS)

    Meyer, Elliot; Chen, Shaojie; Wright, Shelley A.; Moore, Anna M.; Larkin, James E.; Simard, Luc; Marie, Jerome; Mieda, Etsuko; Gordon, Jacob

    2014-07-01

    We present the efficiency of near-infrared reflective ruled diffraction gratings designed for the InfraRed Imaging Spectrograph (IRIS). IRIS is a first light, integral field spectrograph and imager for the Thirty Meter Telescope (TMT) and narrow field infrared adaptive optics system (NFIRAOS). IRIS will operate across the near-infrared encompassing the ZYJHK bands (~0.84 - 2.4μm) with multiple spectral resolutions. We present our experimental setup and analysis of the efficiency of selected reflective diffraction gratings. These measurements are used as a comparison sample against selected candidate Volume Phase Holographic (VPH) gratings (see Chen et al., this conference). We investigate the efficiencies of five ruled gratings designed for IRIS from two separate vendors. Three of the gratings accept a bandpass of 1.19-1.37μm (J band) with ideal spectral resolutions of R=4000 and R=8000, groove densities of 249 and 516 lines/mm, and blaze angles of 9.86° and 20.54° respectively. The other two gratings accept a bandpass of 1.51-1.82μm (H Band) with an ideal spectral resolution of R=4000, groove density of 141 lines/mm, and blaze angle of 9.86°. The fraction of flux in each diffraction mode was compared to both a pure reflection mirror as well as the sum of the flux measured in all observable modes. We measure the efficiencies off blaze angle for all gratings and the efficiencies between the polarization transverse magnetic (TM) and transverse electric (TE) states. The peak reflective efficiencies are 98.90 +/- 3.36% (TM) and 84.99 +/- 2.74% (TM) for the H-band R=4000 and J-band R=4000 respectively. The peak reflective efficiency for the J-band R=8000 grating is 78.78 +/- 2.54% (TE). We find that these ruled gratings do not exhibit a wide dependency on incident angle within +/-3°. Our best-manufactured gratings were found to exhibit a dependency on the polarization state of the incident beam with a ~10-20% deviation, consistent with the theoretical efficiency predictions. This work will significantly contribute to the selection of the final grating type and vendor for the IRIS optical system, and are also pertinent to current and future near-infrared astronomical spectrographs.

  7. The infrared imaging spectrograph (IRIS) for TMT: volume phase holographic grating performance testing and discussion

    NASA Astrophysics Data System (ADS)

    Chen, Shaojie; Meyer, Elliot; Wright, Shelley A.; Moore, Anna M.; Larkin, James E.; Maire, Jerome; Mieda, Etsuko; Simard, Luc

    2014-07-01

    Maximizing the grating efficiency is a key goal for the first light instrument IRIS (Infrared Imaging Spectrograph) currently being designed to sample the diffraction limit of the TMT (Thirty Meter Telescope). Volume Phase Holographic (VPH) gratings have been shown to offer extremely high efficiencies that approach 100% for high line frequencies (i.e., 600 to 6000l/mm), which has been applicable for astronomical optical spectrographs. However, VPH gratings have been less exploited in the near-infrared, particularly for gratings that have lower line frequencies. Given their potential to offer high throughputs and low scattered light, VPH gratings are being explored for IRIS as a potential dispersing element in the spectrograph. Our team has procured near-infrared gratings from two separate vendors. We have two gratings with the specifications needed for IRIS current design: 1.51-1.82μm (H-band) to produce a spectral resolution of 4000 and 1.19-1.37μm (J-band) to produce a spectral resolution of 8000. The center wavelengths for each grating are 1.629μm and 1.27μm, and the groove densities are 177l/mm and 440l/mm for H-band R=4000 and J-band R=8000, respectively. We directly measure the efficiencies in the lab and find that the peak efficiencies of these two types of gratings are quite good with a peak efficiency of ~88% at the Bragg angle in both TM and TE modes at H-band, and 90.23% in TM mode, 79.91% in TE mode at J-band for the best vendor. We determine the drop in efficiency off the Bragg angle, with a 20-23% decrease in efficiency at H-band when 2.5° deviation from the Bragg angle, and 25%-28% decrease at J-band when 5° deviation from the Bragg angle.

  8. Quasi-periodic Oscillation of a Coronal Bright Point

    NASA Astrophysics Data System (ADS)

    Samanta, Tanmoy; Banerjee, Dipankar; Tian, Hui

    2015-06-01

    Coronal bright points (BPs) are small-scale luminous features seen in the solar corona. Quasi-periodic brightenings are frequently observed in the BPs and are generally linked with underlying magnetic flux changes. We study the dynamics of a BP seen in the coronal hole using the Atmospheric Imaging Assembly images, the Helioseismic and Magnetic Imager magnetogram on board the Solar Dynamics Observatory, and spectroscopic data from the newly launched Interface Region Imaging Spectrograph (IRIS). The detailed analysis shows that the BP evolves throughout our observing period along with changes in underlying photospheric magnetic flux and shows periodic brightenings in different EUV and far-UV images. With the highest possible spectral and spatial resolution of IRIS, we attempted to identify the sources of these oscillations. IRIS sit-and-stare observation provided a unique opportunity to study the time evolution of one footpoint of the BP as the slit position crossed it. We noticed enhanced line profile asymmetry, enhanced line width, intensity enhancements, and large deviation from the average Doppler shift in the line profiles at specific instances, which indicate the presence of sudden flows along the line-of-sight direction. We propose that transition region explosive events originating from small-scale reconnections and the reconnection outflows are affecting the line profiles. The correlation between all these parameters is consistent with the repetitive reconnection scenario and could explain the quasi-periodic nature of the brightening.

  9. Source of Quasi-Periodic Brightenings of Solar Coronal Bright Points: Waves or Repeated Reconnections

    NASA Astrophysics Data System (ADS)

    Samanta, Tanmoy; Tian, Hui; Banerjee, Dipankar

    2016-07-01

    Coronal bright points (BPs) are small-scale luminous features seen in the solar corona. Quasi-periodic brightenings are frequently observed in the BPs and are generally linked with underlying magnetic flux changes. We study the dynamics of a BP seen in the coronal hole using the Atmospheric Imaging Assembly images, the Helioseismic and Magnetic Imager magnetogram on board the Solar Dynamics Observatory, and spectroscopic data from the newly launched Interface Region Imaging Spectrograph (IRIS). The detailed analysis shows that the BP evolves throughout our observing period along with changes in underlying photospheric magnetic flux and shows periodic brightenings in different EUV and far-UV images. With the highest possible spectral and spatial resolution of IRIS, we attempted to identify the sources of these oscillations. IRIS sit-and-stare observation provided a unique opportunity to study the time evolution of one footpoint of the BP as the slit position crossed it. We noticed enhanced line profile asymmetry, enhanced line width, intensity enhancements, and large deviation from the average Doppler shift in the line profiles at specific instances, which indicate the presence of sudden flows along the line-of-sight direction. We propose that transition region explosive events originating from small-scale reconnections and the reconnection outflows are affecting the line profiles. The correlation between all these parameters is consistent with the repetitive reconnection scenario and could explain the quasi-periodic nature of the brightening.

  10. The Infrared Imaging Spectrograph (IRIS) for TMT: multi-tiered wavefront measurements and novel mechanical design

    NASA Astrophysics Data System (ADS)

    Dunn, Jennifer; Andersen, David; Chapin, Edward; Reshetov, Vlad; Wierzbicki, Ramunas; Herriot, Glen; Chalmer, Dean; Isbrucker, Victor; Larkin, James E.; Moore, Anna M.; Suzuki, Ryuji

    2016-08-01

    The InfraRed Imaging Spectrograph (IRIS) will be the first light adaptive optics instrument on the Thirty Meter Telescope (TMT). IRIS is being built by a collaboration between Caltech, the University of California, NAOJ and NRC Herzberg. In this paper we present novel aspects of the Support Structure, Rotator and On-Instrument Wavefront Sensor systems being developed at NRC Herzberg. IRIS is suspended from the bottom port of the Narrow Field Infrared Adaptive Optics System (NFIRAOS), and provides its own image de-rotation to compensate for sidereal rotation of the focal plane. This arrangement is a challenge because NFIRAOS is designed to host two other science instruments, which imposes strict mass requirements on IRIS. As the mechanical design of all elements has progressed, we have been tasked with keeping the instrument mass under seven tonnes. This requirement has resulted in a mass reduction of 30 percent for the support structure and rotator compared to the most recent IRIS designs. To accomplish this goal, while still being able to withstand earthquakes, we developed a new design with composite materials. As IRIS is a client instrument of NFIRAOS, it benefits from NFIRAOS's superior AO correction. IRIS plays an important role in providing this correction by sensing low-order aberrations with three On-Instrument Wavefront Sensors (OIWFS). The OIWFS consists of three independently positioned natural guide star wavefront sensor probe arms that patrol a 2-arcminute field of view. We expect tip-tilt measurements from faint stars within the IRIS imager focal plane will further stabilize the delivered image quality. We describe how the use of On-Detector Guide Windows (ODGWs) in the IRIS imaging detector can be incorporated into the AO correction. In this paper, we present our strategies for acquiring and tracking sources with this complex AO system, and for mitigating and measuring the various potential sources of image blur and misalignment due to properties of the mechanical structure and interfaces.

  11. Multi-wavelength Spectral Analysis of Ellerman Bombs Observed by FISS and IRIS

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

    Hong, Jie; Ding, M. D.; Cao, Wenda, E-mail: dmd@nju.edu.cn

    Ellerman bombs (EBs) are a kind of solar activity that is suggested to occur in the lower solar atmosphere. Recent observations using the Interface Region Imaging Spectrograph (IRIS) show connections between EBs and IRIS bombs (IBs), which imply that EBs might be heated to a much higher temperature (8 × 10{sup 4} K) than previous results. Here we perform a spectral analysis of EBs simultaneously observed by the Fast Imaging Solar Spectrograph and IRIS. The observational results show clear evidence of heating in the lower atmosphere, indicated by the wing enhancement in H α , Ca ii 8542 Å, andmore » Mg ii triplet lines and also by brightenings in images of the 1700 Å and 2832 Å ultraviolet continuum channels. Additionally, the intensity of the Mg ii triplet line is correlated with that of H α when an EB occurs, suggesting the possibility of using the triplet as an alternative way to identify EBs. However, we do not find any signal in IRIS hotter lines (C ii and Si iv). For further analysis, we employ a two-cloud model to fit the two chromospheric lines (H α and Ca ii 8542 Å) simultaneously, and obtain a temperature enhancement of 2300 K for a strong EB. This temperature is among the highest of previous modeling results, albeit still insufficient to produce IB signatures at ultraviolet wavelengths.« less

  12. An IRIS Optically Thin View of the Dynamics of the Solar Chromosphere

    NASA Astrophysics Data System (ADS)

    Carlsson, M.

    2017-12-01

    We analyze the formation of the O I 1356 and Cl I 1351 lines and show that they are formed in the mid-chromosphere and are optically thin. Their non-thermal line-widths are thus a direct measure of the velocity field along the line of sight. We use this insight to analyze a large set of observations from the Interface Region Imaging Spectrograph (IRIS) to study the dynamics of the Solar Chromosphere.

  13. Initial Results of a Large-scale Statistical Survey of Small-scale UV Bursts with IRIS and SDO

    NASA Astrophysics Data System (ADS)

    Madsen, C. A.; DeLuca, E.

    2016-12-01

    UV bursts are small-scale ( 1 arcsec or less) brightenings observed in the NUV/FUV passbands of the Interface Region Imaging Spectrograph (IRIS). These peculiar phenomena are found exclusively in active regions and exhibit dramatic and defining spectroscopic characteristics. In particular, they present intense broadening and splitting, often in excess of 70 km s-1, in all bright emission lines observable by IRIS. Furthermore, these broadened lines also display strong absorption from cool metallic ions such as Fe II and Ni II which typically populate the chromosphere. These features suggest that bursts are bidirectional plasma flows at transition region temperatures embedded much farther down in the cool chromosphere. To better characterize these phenomena, we have launched a statistical survey encompassing the entire IRIS data catalogue to date and its accompanying data from the Atmospheric Imaging Assembly (AIA) and Helioseismic and Magnetic Imager (HMI). We sample a wide variety of IRIS observations of Si IV lines, ranging from large 400-step rasters for large detection rates to short-cadence sit-and-stare observations to provide in-depth time evolution data of individual bursts. Detection is streamlined by a semi-automated method that isolates characteristic burst spectra based on single-Gaussian fit parameters, greatly reducing search times in the vast IRIS catalogue. Our initial results demonstrate that UV bursts tend to appear when active regions are young and actively emerging, preferring to populate poorly developed inversion lines composed of numerous small mixed-polarity regions. Burst occurrence rates peak at 30-70 per hour in young active regions, decreasing as those regions age. We also find dramatic variations in spectral morphology in spatial scans of bursts with many split into distinct, opposing, resolved regions of blueshifts and redshifts. Finally, we find little evidence for coronal counterparts in AIA 171 Å, but we do find that a significant ratio of bursts coincide with localized bright features in AIA 1700 Å, lending support to the link between bursts and Ellerman bombs. With further involvement in the survey, we hope to constrain the burst/Ellerman bomb coincidence, the time evolution of burst spectral morphologies, and the distribution of their peak kinetic energies.

  14. Open questions on prominences from coordinated observations by IRIS, Hinode, SDO/AIA, THEMIS, and the Meudon/MSDP

    NASA Astrophysics Data System (ADS)

    Schmieder, B.; Tian, H.; Kucera, T.; López Ariste, A.; Mein, N.; Mein, P.; Dalmasse, K.; Golub, L.

    2014-09-01

    Context. A large prominence was observed by multiple instruments on the ground and in space during an international campaign on September 24, 2013, for three hours (12:12 UT -15:12 UT). Instruments used in the campaign included the newly launched (June 2013) Interface Region Imaging Spectrograph (IRIS), THEMIS (Tenerife), the Hinode Solar Optical Telescope (SOT), the Solar Dynamic Observatory's Atmospheric Imaging Assembly (SDO/AIA), and the Multichannel Subtractive Double Pass spectrograph (MSDP) in the Meudon Solar Tower. The movies obtained in 304 Å with the EUV imager SDO/AIA, and in Ca II line by SOT show the dynamic nature of the prominence. Aims: The aim of this work is to study the dynamics of the prominence fine structures in multiple wavelengths to understand their formation. Methods: The spectrographs IRIS and MSDP provided line profiles with a high cadence in Mg II h (2803.5 Å) and k (2796.4 Å) lines along four slit positions (IRIS), and in Hα in a 2D field of view (MSDP). The spectropolarimetry of THEMIS (Tenerife) allowed us to derive the magnetic field of the prominence using the He D3 line depolarization (Hanle effect combined with the Zeeman effect). Results: The magnetic field is found to be globally horizontal with a relatively weak field strength (8-15 Gauss). On the other hand, the Ca II movie reveals turbulent-like motion that is not organized in specific parts of the prominence. We tested the addition of a turbulent magnetic component. This model is compatible with the polarimetric observations at those places where the plasma turbulence peaks. On the other hand, the Mg II line profiles show multiple peaks well separated in wavelength. This is interpreted by the existence of small threads along the line of sight with a large dispersion of discrete values of Doppler shifts, from 5 km s-1 (a quasi-steady component) to 60-80 km s-1. Each peak corresponds to a Gaussian profile, and not to a reversed profile as was expected by the present non-LTE radiative transfer modeling. This is a very surprising behavior for the Mg II line observed in prominences. Conclusions: Turbulent fields on top of the macroscopic horizontal component of the magnetic field supporting the prominence give rise to the complex dynamics of the plasma. The plasma with the high velocities (70 km s-1 to 100 km s-1 if we take into account the transverse velocities) may correspond to condensation of plasma along more or less horizontal threads of the arch-shape structure visible in 304 Å. The steady flows (5 km s-1) would correspond to a more quiescent plasma (cool and prominence-corona transition region) of the prominence packed into dips in horizontal magnetic field lines. The very weak secondary peaks in the Mg II profiles may reflect the turbulent nature of parts of the prominence. Movies are available in electronic form at http://www.aanda.org

  15. Transition-Region Ultraviolet Explosive Events in IRIS Si IV: A Statistical Analysis

    NASA Astrophysics Data System (ADS)

    Bartz, Allison

    2018-01-01

    Explosive events (EEs) in the solar transition region are characterized by broad, non-Gaussian line profiles with wings at Doppler velocities exceeding the speed of sound. We present a statistical analysis of 23 IRIS (Interface Region Imaging Spectrograph) sit-and-stare observations, observed between April 2014 and March 2017. Using the IRIS Si IV 1394 Å and 1403 Å spectral windows and the 1400Å Slit Jaw images we have identified 581 EEs. We found that most EEs last less than 20 min. and have a spatial scale on the slit less than 10”, agreeing with measurements in previous work. We observed most EEs in active regions, regardless of date of observation, but selection bias of IRIS observations cannot be ruled out. We also present preliminary findings of optical depth effects from our statistical study.

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

    Kwak, Hannah; Chae, Jongchul; Song, Donguk

    We report three-minute oscillations in the solar chromosphere driven by a strong downflow event in a sunspot. We used the Fast Imaging Solar Spectrograph of the 1.6 m New Solar Telescope and the Interface Region Imaging Spectrograph (IRIS). The strong downflow event is identified in the chromospheric and transition region lines above the sunspot umbra. After the event, oscillations occur at the same region. The amplitude of the Doppler velocity oscillations is 2 km s{sup −1} and gradually decreases with time. In addition, the period of the oscillations gradually increases from 2.7 to 3.3 minutes. In the IRIS 1330 Åmore » slit-jaw images, we identify a transient brightening near the footpoint of the downflow detected in the H α +0.5 Å image. The characteristics of the downflowing material are consistent with those of sunspot plumes. Based on our findings, we suggest that the gravitationally stratified atmosphere came to oscillate with a three-minute period in response to the impulsive downflow event as was theoretically investigated by Chae and Goode.« less

  17. Analysis of Inter-Moss Loops in the Solar Region with IRIS and SDO AIA: Automatic Event Detection and Characterization

    NASA Technical Reports Server (NTRS)

    Fayock, Brian; Winebarger, Amy; De Pontieu, Bart; Alexander, Caroline

    2016-01-01

    The Interface Region Imaging Spectrograph (IRIS), launched in the summer of 2013, is designed specifically to observe and investigate the transition region and adjacent layers of the solar atmosphere, obtaining images in high spatial, temporal, and spectral resolution. Our particular work is focused on the evolution of inter-moss loops, which have been detected in the lower corona by the Atmospheric Imaging Assembly (AIA) and the High-Resolution Coronal Imager (Hi- C), but are known to have foot points below the transition region. With the high-resolution capabilities of IRIS and its Si IV pass band, which measures activity in the upper chromosphere, we can study these magnetic loops in detail and compare their characteristic length and time scales to those obtained from several AIA image sets, particularly the 171, 193, and 211 pass bands. By comparing the results between these four data sets, one can potentially establish a measure of the ionization equilibrium for the location in question. To explore this idea, we found a large, sit-and-stare observation within the IRIS database that fit our specifications. This data set contained a number of well-defined inter-moss loops (by visual inspection) with a cadence less than or equal to that of AIA (approximately 12 seconds). This particular data set was recorded on October 23, 2013 at 07:09:30, lasting for 3219 seconds with a field of view of 120.6 by 128.1 arcseconds, centered on -53.9 by 59.1 arcseconds from disk center. For ease of comparison, the AIA data has been interpolated to match the IRIS cadence and resolution. In the main portion of the poster, we demonstrate the detection of events, the information collected, and the immediate results to the right, showing the progress of an event with green as the start, blue as the peak, and red as the end. Below here, we demonstrate how pixels are combined to form groups. The 3D results are shown to the right

  18. Analysis of Inter-Moss Loops in the Solar Region with IRIS and SDO AIA: Automatic Event Detection and Characterization

    NASA Technical Reports Server (NTRS)

    Fayock, Brian; Winebarger, Amy; De Pontieu, Bart

    2014-01-01

    The Interface Region Imaging Spectrograph (IRIS), launched in the summer of 2013, is designed specifically to observe and investigate the transition region and adjacent layers of the solar atmosphere, obtaining images in high spatial, temporal, and spectral resolution. Our particular work is focused on the evolution of inter-moss loops, which have been detected in the lower corona by the Atmospheric Imaging Assembly (AIA) and the High-Resolution Coronal Imager (Hi- C), but are known to have foot points below the transition region. With the high-resolution capabilities of IRIS and its Si IV pass band, which measures activity in the upper chromosphere, we can study these magnetic loops in detail and compare their characteristic length and time scales to those obtained from several AIA image sets, particularly the 171, 193, and 211 pass bands. By comparing the results between these four data sets, one can potentially establish a measure of the ionization equilibrium for the location in question. To explore this idea, we found a large, sit-and-stare observation within the IRIS database that fit our specifications. This data set contained a number of well-defined inter-moss loops (by visual inspection) with a cadence less than or equal to that of AIA (approximately 12 seconds). This particular data set was recorded on October 23, 2013 at 07:09:30, lasting for 3219 seconds with a field of view of 120.6 by 128.1 arcseconds, centered on -53.9 by 59.1 arcseconds from disk center. For ease of comparison, the AIA data has been interpolated to match the IRIS cadence and resolution. In the main portion of the poster, we demonstrate the detection of events, the information collected, and the immediate results to the right, showing the progress of an event with green as the start, blue as the peak, and red as the end. Below here, we demonstrate how pixels are combined to form groups. The 3D results are shown to the right.

  19. NON-LTE INVERSIONS OF THE Mg ii h and k AND UV TRIPLET LINES

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

    De la Cruz Rodríguez, Jaime; Leenaarts, Jorrit; Ramos, Andrés Asensio

    The Mg ii h and k lines are powerful diagnostics for studying the solar chromosphere. They have become particularly popular with the launch of the Interface Region Imaging Spectrograph ( IRIS ) satellite, and a number of studies that include these lines have lead to great progress in understanding chromospheric heating, in many cases thanks to the support from 3D MHD simulations. In this study, we utilize another approach to analyze observations: non-LTE inversions of the Mg ii h and k and UV triplet lines including the effects of partial redistribution. Our inversion code attempts to construct a model atmospheremore » that is compatible with the observed spectra. We have assessed the capabilities and limitations of the inversions using the FALC atmosphere and a snapshot from a 3D radiation-MHD simulation. We find that Mg ii h and k allow reconstructing a model atmosphere from the middle photosphere to the transition region. We have also explored the capabilities of a multi-line/multi-atom setup, including the Mg ii h and k, the Ca ii 854.2 nm, and the Fe i 630.25 lines to recover the full stratification of physical parameters, including the magnetic field vector, from the photosphere to the chromosphere. Finally, we present the first inversions of observed IRIS spectra from quiet-Sun, plage, and sunspot, with very promising results.« less

  20. CHROMOSPHERIC EVAPORATION IN AN X1.0 FLARE ON 2014 MARCH 29 OBSERVED WITH IRIS AND EIS

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

    Li, Y.; Ding, M. D.; Qiu, J.

    Chromospheric evaporation refers to dynamic mass motions in flare loops as a result of rapid energy deposition in the chromosphere. These motions have been observed as blueshifts in X-ray and extreme-ultraviolet (EUV) spectral lines corresponding to upward motions at a few tens to a few hundreds of km s{sup −1}. Past spectroscopic observations have also revealed a dominant stationary component, in addition to the blueshifted component, in emission lines formed at high temperatures (∼10 MK). This is contradictory to evaporation models predicting predominant blueshifts in hot lines. The recently launched Interface Region Imaging Spectrograph (IRIS) provides high-resolution imaging and spectroscopicmore » observations that focus on the chromosphere and transition region in the UV passband. Using the new IRIS observations, combined with coordinated observations from the EUV Imaging Spectrometer, we study the chromospheric evaporation process from the upper chromosphere to the corona during an X1.0 flare on 2014 March 29. We find evident evaporation signatures, characterized by Doppler shifts and line broadening, at two flare ribbons that are separating from each other, suggesting that chromospheric evaporation takes place in successively formed flaring loops throughout the flare. More importantly, we detect dominant blueshifts in the high-temperature Fe xxi line (∼10 MK), in agreement with theoretical predictions. We also find that, in this flare, gentle evaporation occurs at some locations in the rise phase of the flare, while explosive evaporation is detected at some other locations near the peak of the flare. There is a conversion from gentle to explosive evaporation as the flare evolves.« less

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

    De Pontieu, B.; Martinez-Sykora, J.; McIntosh, S.

    Spectral observations of the solar transition region (TR) and corona show broadening of spectral lines beyond what is expected from thermal and instrumental broadening. The remaining non-thermal broadening is significant (5–30 km s{sup −1}) and correlated with intensity. Here we study spectra of the TR Si iv 1403 Å line obtained at high resolution with the Interface Region Imaging Spectrograph (IRIS). We find that the large improvement in spatial resolution (0.″33) of IRIS compared to previous spectrographs (2″) does not resolve the non-thermal line broadening which, in most regions, remains at pre-IRIS levels of about 20 km s{sup −1}. Thismore » invariance to spatial resolution indicates that the processes behind the broadening occur along the line-of-sight (LOS) and/or on spatial scales (perpendicular to the LOS) smaller than 250 km. Both effects appear to play a role. Comparison with IRIS chromospheric observations shows that, in regions where the LOS is more parallel to the field, magneto-acoustic shocks driven from below impact the TR and can lead to significant non-thermal line broadening. This scenario is supported by MHD simulations. While these do not show enough non-thermal line broadening, they do reproduce the long-known puzzling correlation between non-thermal line broadening and intensity. This correlation is caused by the shocks, but only if non-equilibrium ionization is taken into account. In regions where the LOS is more perpendicular to the field, the prevalence of small-scale twist is likely to play a significant role in explaining the invariance and correlation with intensity. (letters)« less

  2. KSC-2012-5328

    NASA Image and Video Library

    2012-09-13

    VANDENBERG AFB, Calif. – Technicians perform a fit check on an Orbital Sciences Pegasus rocket as the launcher is processed for the Interface Region Imaging Spectrograph mission known as IRIS. The technicians are attaching the portion of the Pegasus that joins the wing to the fuselage, a piece called a fillet. Photo credit: VAFB/Randy Beaudoin

  3. KSC-2012-5326

    NASA Image and Video Library

    2012-09-13

    VANDENBERG AFB, Calif. – Technicians perform a fit check on an Orbital Sciences Pegasus rocket as the launcher is processed for the Interface Region Imaging Spectrograph mission known as IRIS. The technicians are attaching the portion of the Pegasus that joins the wing to the fuselage, a piece called a fillet. Photo credit: VAFB/Randy Beaudoin

  4. KSC-2012-5327

    NASA Image and Video Library

    2012-09-13

    VANDENBERG AFB, Calif. – Technicians perform a fit check on an Orbital Sciences Pegasus rocket as the launcher is processed for the Interface Region Imaging Spectrograph mission known as IRIS. The technicians are attaching the portion of the Pegasus that joins the wing to the fuselage, a piece called a fillet. Photo credit: VAFB/Randy Beaudoin

  5. KSC-2012-5325

    NASA Image and Video Library

    2012-09-13

    VANDENBERG AFB, Calif. – Technicians perform a fit check on an Orbital Sciences Pegasus rocket as the launcher is processed for the Interface Region Imaging Spectrograph mission known as IRIS. The technicians are attaching the portion of the Pegasus that joins the wing to the fuselage, a piece called a fillet. Photo credit: VAFB/Randy Beaudoin

  6. The Road to IRIS data products

    NASA Astrophysics Data System (ADS)

    Hurlburt, N. E.; Title, A. M.; De Pontieu, B.; Lemen, J. R.; Wuelser, J.; Tarbell, T. D.; Wolfson, C. J.; Schrijver, C. J.; Golub, L.; DeLuca, E. E.; Kankelborg, C. C.; Hansteen, V. H.; Carlsson, M.; Bush, R. I.

    2013-12-01

    The Interface Region Imaging Spectrograph generates a complex set of data products that the IRIS team has strived to deliver to the community in forms that are easy to find and use. We review the results of these efforts and invite the community to explore the data and tools. All standard IRIS data products are based on calibrated images are corrected for a variety of instrumental effects. The resulting products are incorporated into the Heliophysics Event Knowledgebase (HEK) as annotated data sets accessible through the HEK Coverage Registry (HCR). Annotations include descriptions of the data products themselves (pointing, field of view, cadence...) as well as references to coordinated observations from the Hinode mission and other observatories, and to solar events identified in the HEK Event Registry (HER). IRIS data products are available at the LMSAL and Stanford (JSOC) data centers in Palo Alto and the Hinode Data Center in Oslo. Portals that can help users to select data products include the LMSAL iSolsearch, the Virtual Solar Observatory and Helioviewer. Supporting analysis software is available in the IRIS branch of SolarSoft.

  7. UV and X-ray Evolution of AR12230 as Observed with IRIS and FOXSI-II

    NASA Astrophysics Data System (ADS)

    Ryan, Daniel; Christe, Steven; Glesener, Lindsay; Vievering, Julie; Krucker, Sam; Ishikawa, Shin-Nosuke

    2017-08-01

    We present a multi-spectral and spatio-temporal analysis of AR12230 using both UV and X-ray spectroscopic imaging obtained as part of a coordinated observing campaign on 11 December 2014. The campaign involved IRIS (Interface Region Imaging Spectrometer) -- which provides both UV imaging and slit spectrograph observations of optically thick chromospheric and transition region emission -- and FOXSI-II (Focusing Optics X-ray Solar Imager) -- the second in a series of sounding rocket flights which combines grazing incidence direct focusing optics to produce solar X-ray spectroscopic imaging in the range 4-15keV. The active region exhibits a prolonged compact brightening in the IRIS 1330 A and 1400 A slit-jaw channels near the center of the active region throughout the duration of the observations. In the early phase of the observations FOXSI-II shows an X-ray source approximately 20x20 arcsec centered at the same location. The X-ray spectra show the presence of hot (~8 MK) thermal plasma and is suggestive of the presence of non-thermal electrons.. Later, two additional transient, spatially extended, simultaneous brightenings are observed, one of which was captured by the IRIS slit spectrograph. We combine these observations to explore the evolution and topology of the active region. Hydrodynamic modeling of the chromosphere is used to place a limit on the amount of non-thermal electrons required to produce the observed UV emission. This result is then compared to the limit inferred from the FOXSI-II X-ray spectra. Thus, we explore the role of non-thermal electrons and hydrodynamics in the energization and evolution of plasma in active regions.

  8. NASA's Best-Observed X-Class Flare of All Time

    NASA Image and Video Library

    2014-05-07

    Like almost all solar observatories, NASA's IRIS can provide images of different layers of the sun's atmosphere, which together create a whole picture of what's happening. This image shows light at a wavelength of 1400 Angstrom, which highlights material some 650 miles above the sun's surface. The vertical line in the middle shows the slit for IRIS's spectrograph, which can separate light into its many wavelengths to provide even more information about the temperature and velocity of material during a flare. Credit: NASA/IRIS/Goddard Space Flight Center -- On March 29, 2014 the sun released an X-class flare. It was observed by NASA's Interface Region Imaging Spectrograph, or IRIS; NASA's Solar Dynamics Observatory, or SDO; NASA's Reuven Ramaty High Energy Solar Spectroscopic Imager, or RHESSI; the Japanese Aerospace Exploration Agency's Hinode; and the National Solar Observatory's Dunn Solar Telescope located at Sacramento Peak in New Mexico. To have a record of such an intense flare from so many observatories is unprecedented. Such research can help scientists better understand what catalyst sets off these large explosions on the sun. Perhaps we may even some day be able to predict their onset and forewarn of the radio blackouts solar flares can cause near Earth - blackouts that can interfere with airplane, ship and military communications. Read more: 1.usa.gov/1kMDQbO Join our Google+ Hangout on May 8 at 2:30pm EST: go.nasa.gov/1mwbBEZ Credit: NASA Goddard 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

  9. IRIS Ultraviolet Spectral Properties of a Sample of X-Class Solar Flares

    NASA Astrophysics Data System (ADS)

    Butler, Elizabeth; Kowalski, Adam; Cauzzi, Gianna; Allred, Joel C.; Daw, Adrian N.

    2018-06-01

    The white-light (near-ultraviolet (NUV) and optical) continuum emission comprises the majority of the radiated energy in solar flares. However, there are nearly as many explanations for the origin of the white-light continuum radiation as there are white-light flares that have been studied in detail with spectra. Furthermore, there are rarely robust constraints on the time-resolved dynamics in the white-light emitting flare layers. We are conducting a statistical study of the properties of Fe II lines, Mg II lines, and NUV continuum intensity in bright flare kernels observed by the Interface Region Imaging Spectrograph (IRIS), in order to provide comprehensive constraints for radiative-hydrodynamic flare models. Here we present a new technique for identifying bright flare kernels and preliminary relationships among IRIS spectral properties for a sample of X-class solar flares.

  10. The IRIS-GUS Shuttle Borne Upper Stage System

    NASA Technical Reports Server (NTRS)

    Tooley, Craig; Houghton, Martin; Bussolino, Luigi; Connors, Paul; Broudeur, Steve (Technical Monitor)

    2002-01-01

    This paper describes the Italian Research Interim Stage - Gyroscopic Upper Stage (IRIS-GUS) upper stage system that will be used to launch NASA's Triana Observatory from the Space Shuttle. Triana is a pathfinder earth science mission being executed on rapid schedule and small budget, therefore the mission's upper stage solution had to be a system that could be fielded quickly at relatively low cost and risk. The building of the IRIS-GUS system wa necessary because NASA lost the capability to launch moderately sized upper stage missions fro the Space Shuttle when the PAM-D system was retired. The IRIS-GUS system restores this capability. The resulting system is a hybrid which mates the existing, flight proven IRIS (Italian Research Interim Stage) airborne support equipment to a new upper stage, the Gyroscopic Upper Stage (GUS) built by the GSFC for Triana. Although a new system, the GUS exploits flight proven hardware and design approaches in most subsystems, in some cases implementing proven design approaches with state-of-the-art electronics. This paper describes the IRIS-GUS upper stage system elements, performance capabilities, and payload interfaces.

  11. Solar glint suppression in compact planetary ultraviolet spectrographs

    NASA Astrophysics Data System (ADS)

    Davis, Michael W.; Cook, Jason C.; Grava, Cesare; Greathouse, Thomas K.; Gladstone, G. Randall; Retherford, Kurt D.

    2015-08-01

    Solar glint suppression is an important consideration in the design of compact photon-counting ultraviolet spectrographs. Southwest Research Institute developed the Lyman Alpha Mapping Project for the Lunar Reconnaissance Orbiter (launch in 2009), and the Ultraviolet Spectrograph on Juno (Juno-UVS, launch in 2011). Both of these compact spectrographs revealed minor solar glints in flight that did not appear in pre-launch analyses. These glints only appeared when their respective spacecraft were operating outside primary science mission parameters. Post-facto scattered light analysis verifies the geometries at which these glints occurred and why they were not caught during ground testing or nominal mission operations. The limitations of standard baffle design at near-grazing angles are discussed, as well as the importance of including surface scatter properties in standard stray light analyses when determining solar keep-out efficiency. In particular, the scattered light analysis of these two instruments shows that standard "one bounce" assumptions in baffle design are not always enough to prevent scattered sunlight from reaching the instrument focal plane. Future builds, such as JUICE-UVS, will implement improved scattered and stray light modeling early in the design phase to enhance capabilities in extended mission science phases, as well as optimize solar keep out volume.

  12. DYNAMICS OF ON-DISK PLUMES AS OBSERVED WITH THE INTERFACE REGION IMAGING SPECTROGRAPH, THE ATMOSPHERIC IMAGING ASSEMBLY, AND THE HELIOSEISMIC AND MAGNETIC IMAGER

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

    Pant, Vaibhav; Mazumder, Rakesh; Banerjee, Dipankar

    2015-07-01

    We examine the role of small-scale transients in the formation and evolution of solar coronal plumes. We study the dynamics of plume footpoints seen in the vicinity of a coronal hole using the Atmospheric Imaging Assembly (AIA) images, the Helioseismic and Magnetic Imager magnetogram on board the Solar Dynamics Observatory and spectroscopic data from the Interface Region Imaging Spectrograph (IRIS). Quasi-periodic brightenings are observed in the base of the plumes and are associated with magnetic flux changes. With the high spectral and spatial resolution of IRIS, we identify the sources of these oscillations and try to understand what role themore » transients at the footpoints can play in sustaining the coronal plumes. IRIS “sit-and-stare” observations provide a unique opportunity to study the evolution of footpoints of the plumes. We notice enhanced line width and intensity, and large deviation from the average Doppler shift in the line profiles at specific instances, which indicate the presence of flows at the footpoints of plumes. We propose that outflows (jet-like features) as a result of small-scale reconnections affect the line profiles. These jet-like features may also be responsible for the generation of propagating disturbances (PDs) within the plumes, which are observed to be propagating to larger distances as recorded from multiple AIA channels. These PDs can be explained in terms of slow magnetoacoustic waves.« less

  13. Spectral Analysis Flare ribbons by NST and IRIS

    NASA Astrophysics Data System (ADS)

    Huang, Nengyi; Xu, Yan; Wang, Haimin; Jing, Ju

    2017-08-01

    As one of the most powerful phenomena of solar activities, flares have long been observed and studied extensively. Taking advantages of observing capabilities of modern solar telescopes and focal-plane instruments such as the Interface Region Imaging Spectrograph (IRIS) and the 1.6 m New Solar Telescope (NST) at Big Bear Solar observatory (BBSO), we are able to obtain high resolution imaging spectroscopic data in UV, visible and near-infrared (NIR) wavelengths. Here we present the spectral analysis of an M6.5 flare (SOL2015-06-22T18:23) which was well covered by the joint observation of IRIS and NST. In the visible wavelengths H-alpha and TiO, we can separate the flare ribbon into a very narrow leading front and faint trailing component, of which the former is characterized by the intense emission and significant Doppler signals. In the IRIS UV spectra, the ribbon front shows distinct properties, such as the line broadening, Doppler shifts and central reversal pattern, which are consistent with the visible observations. These characteristics suggest that the ribbon front to be the p

  14. GNOSIS: The First Fiber Bragg Grating-based OH Suppression Unit

    NASA Astrophysics Data System (ADS)

    Trinh, Christopher; Ellis, S. C.; Bland-Hawthorn, J.; Lawrence, J. S.; Horton, A. J.; Leon-Saval, S. G.; Shortridge, K.; Bryant, J.; Case, S.; Colless, M.; Couch, W.; Freeman, K. C.; Löhmannsröben, H.; Gers, L.; Glazebrook, K.; Haynes, R.; Lee, S.; O'Byrne, J.; Miziarski, S.; Roth, M. M.; Schmidt, B.; Tinney, C. G.; Zheng, J.

    2013-01-01

    The sky background is over 1000 times brighter in the near-infrared (NIR) than in the visible placing severe limitations on our ability to study the redshifted light from the distant objects formed in the early Universe from the ground. It is well-known that 98% of the NIR background comes from the forest of bright and highly variable emission lines of atmospheric hydroxyl (OH) molecules. Unfortunately, astronomers have been unable to effectively remove this background from their data. We present the first OH suppression unit, GNOSIS, to utilize fiber Bragg gratings (FBGs). Simple FBGs are optical fibers with a periodic refractive index modulation imprinted within the fiber core, which induces a strong reflection in a narrow 0.2 nm) stopband. GNOSIS utilizes “OH suppression fibers” with a complex aperiodic refractive index modulation capable of removing the 103 brightest OH doublets between 1470 and 1700 nm by up 30 dB before dispersion and in a manner purely dependent on wavelength. The OH suppression fibers have high throughput 60%) and over 90% of the H band is available for spectroscopy. OH suppression units like GNOSIS may be utilized with any NIR telescope and spectrograph combination, but we commissioned GNOSIS at the 3.9-meter Anglo-Australian Telescope with the IRIS2 spectrograph for our first demonstration. Commissioning reveals excellent suppression performance. Approximately 78% of the OH lines were suppressed at the target level or greater. GNOSIS reduces the integrated background between 1500 and 1700 nm by a factor of ~ 9 but the signal-to-noise ratio is about the same as standard long-slit IRIS2 observations due to retrofitting to an un-optimized spectrograph. Nevertheless, if paired with a fiber-optimized spectrograph FBG OH suppression technology shows great promise for high sensitivity NIR spectroscopy at moderate to low resolutions from the ground.

  15. HYDROGEN BALMER CONTINUUM IN SOLAR FLARES DETECTED BY THE INTERFACE REGION IMAGING SPECTROGRAPH (IRIS)

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

    Heinzel, P.; Kleint, L., E-mail: pheinzel@asu.cas.cz

    We present a novel observation of the white light flare (WLF) continuum, which was significantly enhanced during the X1 flare on 2014 March 29 (SOL2014-03-29T17:48). Data from the Interface Region Imaging Spectrograph (IRIS) in its near-UV channel show that at the peak of the continuum enhancement, the contrast at the quasi-continuum window above 2813 Å reached 100%-200% and can be even larger closer to Mg II lines. This is fully consistent with the hydrogen recombination Balmer-continuum emission, which follows an impulsive thermal and non-thermal ionization caused by the precipitation of electron beams through the chromosphere. However, a less probable photosphericmore » continuum enhancement cannot be excluded. The light curves of the Balmer continuum have an impulsive character with a gradual fading, similar to those detected recently in the optical region on the Solar Optical Telescope on board Hinode. This observation represents a first Balmer-continuum detection from space far beyond the Balmer limit (3646 Å), eliminating seeing effects known to complicate the WLF detection. Moreover, we use a spectral window so far unexplored for flare studies, which provides the potential to study the Balmer continuum, as well as many metallic lines appearing in emission during flares. Combined with future ground-based observations of the continuum near the Balmer limit, we will be able to disentangle various scenarios of the WLF origin. IRIS observations also provide a critical quantitative measure of the energy radiated in the Balmer continuum, which constrains various models of the energy transport and deposit during flares.« less

  16. A New Approach to Observing Coronal Dynamics: MUSE, the Multi-Slit Solar Explorer

    NASA Astrophysics Data System (ADS)

    Tarbell, T. D.

    2017-12-01

    The Multi-Slit Solar Explorer is a Small Explorer mission recently selected for a Phase A study, which could lead to a launch in 2022. It will provide unprecendented observations of the dynamics of the corona and transition region using both conventional and novel spectral imaging techniques. The physical processes that heat the multi-million degree solar corona, accelerate the solar wind and drive solar activity (CMEs and flares) remain poorly known. A breakthrough in these areas can only come from radically innovative instrumentation and state-of-the-art numerical modeling and will lead to better understanding of space weather origins. MUSE's multi-slit coronal spectroscopy will exploit a 100x improvement in spectral raster cadence to fill a crucial gap in our knowledge of Sun-Earth connections; it will reveal temperatures, velocities and non-thermal processes over a wide temperature range to diagnose physical processes that remain invisible to current or planned instruments. MUSE will contain two instruments: an EUV spectrograph (SG) and EUV context imager (CI). Both have similar spatial resolution and leverage extensive heritage from previous high-resolution instruments such as IRIS and the HiC rocket payload. The MUSE investigation will build on the success of IRIS by combining numerical modeling with a uniquely capable observatory: MUSE will obtain EUV spectra and images with the highest resolution in space (1/3 arcsec) and time (1-4 s) ever achieved for the transition region and corona, along 35 slits and a large context FOV simultaneously. The MUSE consortium includes LMSAL, SAO, Stanford, ARC, HAO, GSFC, MSFC, MSU, ITA Oslo and other institutions.

  17. GNOSIS: THE FIRST INSTRUMENT TO USE FIBER BRAGG GRATINGS FOR OH SUPPRESSION

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

    Trinh, Christopher Q.; Ellis, Simon C.; Bland-Hawthorn, Joss

    The near-infrared is an important part of the spectrum in astronomy, especially in cosmology because the light from objects in the early universe is redshifted to these wavelengths. However, deep near-infrared observations are extremely difficult to make from ground-based telescopes due to the bright background from the atmosphere. Nearly all of this background comes from the bright and narrow emission lines of atmospheric hydroxyl (OH) molecules. The atmospheric background cannot be easily removed from data because the brightness fluctuates unpredictably on short timescales. The sensitivity of ground-based optical astronomy far exceeds that of near-infrared astronomy because of this long-standing problem.more » GNOSIS is a prototype astrophotonic instrument that utilizes 'OH suppression fibers' consisting of fiber Bragg gratings and photonic lanterns to suppress the 103 brightest atmospheric emission doublets between 1.47 and 1.7 {mu}m. GNOSIS was commissioned at the 3.9 m Anglo-Australian Telescope with the IRIS2 spectrograph to demonstrate the potential of OH suppression fibers, but may be potentially used with any telescope and spectrograph combination. Unlike previous atmospheric suppression techniques GNOSIS suppresses the lines before dispersion and in a manner that depends purely on wavelength. We present the instrument design and report the results of laboratory and on-sky tests from commissioning. While these tests demonstrated high throughput ( Almost-Equal-To 60%) and excellent suppression of the skylines by the OH suppression fibers, surprisingly GNOSIS produced no significant reduction in the interline background and the sensitivity of GNOSIS+IRIS2 is about the same as IRIS2. It is unclear whether the lack of reduction in the interline background is due to physical sources or systematic errors as the observations are detector noise dominated. OH suppression fibers could potentially impact ground-based astronomy at the level of adaptive optics or greater. However, until a clear reduction in the interline background and the corresponding increasing in sensitivity is demonstrated optimized OH suppression fibers paired with a fiber-fed spectrograph will at least provide a real benefit at low resolving powers.« less

  18. GNOSIS: The First Instrument to Use Fiber Bragg Gratings for OH Suppression

    NASA Astrophysics Data System (ADS)

    Trinh, Christopher Q.; Ellis, Simon C.; Bland-Hawthorn, Joss; Lawrence, Jon S.; Horton, Anthony J.; Leon-Saval, Sergio G.; Shortridge, Keith; Bryant, Julia; Case, Scott; Colless, Matthew; Couch, Warrick; Freeman, Kenneth; Löhmannsröben, Hans-Gerd; Gers, Luke; Glazebrook, Karl; Haynes, Roger; Lee, Steve; O'Byrne, John; Miziarski, Stan; Roth, Martin M.; Schmidt, Brian; Tinney, Christopher G.; Zheng, Jessica

    2013-02-01

    The near-infrared is an important part of the spectrum in astronomy, especially in cosmology because the light from objects in the early universe is redshifted to these wavelengths. However, deep near-infrared observations are extremely difficult to make from ground-based telescopes due to the bright background from the atmosphere. Nearly all of this background comes from the bright and narrow emission lines of atmospheric hydroxyl (OH) molecules. The atmospheric background cannot be easily removed from data because the brightness fluctuates unpredictably on short timescales. The sensitivity of ground-based optical astronomy far exceeds that of near-infrared astronomy because of this long-standing problem. GNOSIS is a prototype astrophotonic instrument that utilizes "OH suppression fibers" consisting of fiber Bragg gratings and photonic lanterns to suppress the 103 brightest atmospheric emission doublets between 1.47 and 1.7 μm. GNOSIS was commissioned at the 3.9 m Anglo-Australian Telescope with the IRIS2 spectrograph to demonstrate the potential of OH suppression fibers, but may be potentially used with any telescope and spectrograph combination. Unlike previous atmospheric suppression techniques GNOSIS suppresses the lines before dispersion and in a manner that depends purely on wavelength. We present the instrument design and report the results of laboratory and on-sky tests from commissioning. While these tests demonstrated high throughput (≈60%) and excellent suppression of the skylines by the OH suppression fibers, surprisingly GNOSIS produced no significant reduction in the interline background and the sensitivity of GNOSIS+IRIS2 is about the same as IRIS2. It is unclear whether the lack of reduction in the interline background is due to physical sources or systematic errors as the observations are detector noise dominated. OH suppression fibers could potentially impact ground-based astronomy at the level of adaptive optics or greater. However, until a clear reduction in the interline background and the corresponding increasing in sensitivity is demonstrated optimized OH suppression fibers paired with a fiber-fed spectrograph will at least provide a real benefit at low resolving powers.

  19. GNOSIS: an OH suppression unit for near-infrared spectrographs

    NASA Astrophysics Data System (ADS)

    Ellis, S. C.; Bland-Hawthorn, J.; Lawrence, J. S.; Bryant, J.; Haynes, R.; Horton, A.; Lee, S.; Leon-Saval, S.; Löhmannsröben, Hans-Gerd; Mladenoff, J.; O'Byrne, J.; Rambold, W.; Roth, M.; Trinh, C.

    2010-07-01

    GNOSIS is an OH suppression unit to be used in conjunction with existing spectrographs. The OH suppression is achieved using fibre Bragg gratings (FBGs), and will deliver the darkest near-infrared background of any ground-based instrument. Laboratory and on-sky tests demonstrate that FBGs can suppress OH lines by 30dB whilst maintaing > 90% throughput between the lines, resulting in a 4 mag decrease in the background. In the first implementation GNOSIS will feed IRIS2 on the AAT. It will consist of a seven element lenslet array, covering 1.4" on the sky, and will suppress the 103 brightest OH lines between 1.47 and 1.70 μm. Future upgrades will include J-band suppression and implementation on an 8m telescope.

  20. Prominence and tornado dynamics observed with IRIS and THEMIS

    NASA Astrophysics Data System (ADS)

    Schmieder, Brigitte; Levens, Peter; Labrosse, Nicolas; Mein, Pierre; Lopez Ariste, Arturo; Zapior, Maciek

    2017-08-01

    Several prominences were observed during campaigns in September 2013 and July 2014 with the IRIS spectrometer and the vector magnetograph THEMIS (Tenerife). SDO/AIA and IRIS provided images and spectra of prominences and tornadoes corresponding to different physical conditions of the transition region between the cool plasma and the corona. The vector magnetic field was derived from THEMIS observations by using the He D3 depolarisation due to the magnetic field. The inversion code (PCA) takes into account the Hanle and Zeeman effects and allows us to compute the strength and the inclination of the magnetic field which is shown to be mostly horizontal in prominences as well as in tornadoes. Movies from SDO/AIA in 304 A and Hinode/SOT in Ca II show the highly dynamic nature of the fine structures. From spectra in Mg II and Si IV lines provided by IRIS and H-alpha observed by the Multi-channel Subtractive Double Pass (MSDP) spectrograph in the Meudon Solar Tower we derived the Doppler shifts of the fine structures and reconstructed the 3D structure of tornadoes. We conclude that the apparent rotation of AIA tornadoes is due to large-scale quasi-periodic oscillations of the plasma along more or less horizontal magnetic structures.

  1. Structure and Dynamics of Cool Flare Loops Observed by the Interface Region Imaging Spectrograph

    NASA Astrophysics Data System (ADS)

    Mikuła, K.; Heinzel, P.; Liu, W.; Berlicki, A.

    2017-08-01

    Flare loops were well observed with the Interface Region Imaging Spectrograph (IRIS) during the gradual phase of two solar flares on 2014 March 29 and 2015 June 22. Cool flare loops are visible in various spectral lines formed at chromospheric and transition-region temperatures and exhibit large downflows which correspond to the standard scenario. The principal aim of this work is to analyze the structure and dynamics of cool flare loops observed in Mg II lines. Synthetic profiles of the Mg II h line are computed using the classical cloud model and assuming a uniform background intensity. In this paper, we study novel IRIS NUV observations of such loops in Mg II h and k lines and also show the behavior of hotter lines detected in the FUV channel. We obtained the spatial evolution of the velocities: near the loop top, the flow velocities are small and they are increasing toward the loop legs. Moreover, from slit-jaw image (SJI) movies, we observe some plasma upflows into the loops, which are also detectable in Mg II spectra. The brightness of the loops systematically decreases with increasing flow velocity, and we ascribe this to the effect of Doppler dimming, which works for Mg II lines. Emission profiles of Mg II were found to be extremely broad, and we explain this through the large unresolved non-thermal motions.

  2. Structure and Dynamics of Cool Flare Loops Observed by the Interface Region Imaging Spectrograph

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

    Mikuła, K.; Berlicki, A.; Heinzel, P.

    Flare loops were well observed with the Interface Region Imaging Spectrograph ( IRIS ) during the gradual phase of two solar flares on 2014 March 29 and 2015 June 22. Cool flare loops are visible in various spectral lines formed at chromospheric and transition-region temperatures and exhibit large downflows which correspond to the standard scenario. The principal aim of this work is to analyze the structure and dynamics of cool flare loops observed in Mg ii lines. Synthetic profiles of the Mg ii h line are computed using the classical cloud model and assuming a uniform background intensity. In thismore » paper, we study novel IRIS NUV observations of such loops in Mg ii h and k lines and also show the behavior of hotter lines detected in the FUV channel. We obtained the spatial evolution of the velocities: near the loop top, the flow velocities are small and they are increasing toward the loop legs. Moreover, from slit-jaw image (SJI) movies, we observe some plasma upflows into the loops, which are also detectable in Mg ii spectra. The brightness of the loops systematically decreases with increasing flow velocity, and we ascribe this to the effect of Doppler dimming, which works for Mg ii lines. Emission profiles of Mg ii were found to be extremely broad, and we explain this through the large unresolved non-thermal motions.« less

  3. ELLERMAN BOMBS AT HIGH RESOLUTION. III. SIMULTANEOUS OBSERVATIONS WITH IRIS AND SST

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

    Vissers, G. J. M.; Voort, L. H. M. Rouppe van der; Rutten, R. J.

    Ellerman bombs (EBs) are transient brightenings of the extended wings of the solar Balmer lines in emerging active regions. We describe their properties in the ultraviolet lines sampled by the Interface Region Imaging Spectrograph (IRIS), using simultaneous imaging spectroscopy in Hα with the Swedish 1-m Solar Telescope (SST) and ultraviolet images from the Solar Dynamics Observatory for Ellerman bomb detection and identification. We select multiple co-observed EBs for detailed analysis. The IRIS spectra strengthen the view that EBs mark reconnection between bipolar kilogauss fluxtubes with the reconnection and the resulting bi-directional jet located within the solar photosphere and shielded bymore » overlying chromospheric fibrils in the cores of strong lines. The spectra suggest that the reconnecting photospheric gas underneath is heated sufficiently to momentarily reach stages of ionization normally assigned to the transition region and the corona. We also analyze similar outburst phenomena that we classify as small flaring arch filaments and ascribe to reconnection at a higher location. They have different morphologies and produce hot arches in million-Kelvin diagnostics.« less

  4. Observation and modelling of the Fe XXI line profile observed by IRIS during the impulsive phase of flares

    NASA Astrophysics Data System (ADS)

    Polito, V.; Testa, P.; De Pontieu, B.; Allred, J. C.

    2017-12-01

    The observation of the high temperature (above 10 MK) Fe XXI 1354.1 A line with the Interface Region Imaging Spectrograph (IRIS) has provided significant insights into the chromospheric evaporation process in flares. In particular, the line is often observed to be completely blueshifted, in contrast to previous observations at lower spatial and spectral resolution, and in agreement with predictions from theoretical models. Interestingly, the line is also observed to be mostly symmetric and with a large excess above the thermal width. One popular interpretation for the excess broadening is given by assuming a superposition of flows from different loop strands. In this work, we perform a statistical analysis of Fe XXI line profiles observed by IRIS during the impulsive phase of flares and compare our results with hydrodynamic simulations of multi-thread flare loops performed with the 1D RADYN code. Our results indicate that the multi-thread models cannot easily reproduce the symmetry of the line and that some other physical process might need to be invoked in order to explain the observed profiles.

  5. Development of the MAMA Detectors for the Hubble Space Telescope Imaging Spectrograph

    NASA Technical Reports Server (NTRS)

    Timothy, J. Gethyn

    1997-01-01

    The development of the Multi-Anode Microchannel Array (MAMA) detector systems started in the early 1970's in order to produce multi-element detector arrays for use in spectrographs for solar studies from the Skylab-B mission. Development of the MAMA detectors for spectrographs on the Hubble Space Telescope (HST) began in the late 1970's, and reached its culmination with the successful installation of the Space Telescope Imaging Spectrograph (STIS) on the second HST servicing mission (STS-82 launched 11 February 1997). Under NASA Contract NAS5-29389 from December 1986 through June 1994 we supported the development of the MAMA detectors for STIS, including complementary sounding rocket and ground-based research programs. This final report describes the results of the MAMA detector development program for STIS.

  6. Characterization and on-sky demonstration of an integrated photonic spectrograph for astronomy.

    PubMed

    Cvetojevic, N; Lawrence, J S; Ellis, S C; Bland-Hawthorn, J; Haynes, R; Horton, A

    2009-10-12

    We present results from the first on-sky demonstration of a prototype astronomical integrated photonic spectrograph (IPS) using the Anglo-Australian Telescope near-infrared imaging spectrometer (IRIS2) at Siding Spring Observatory to observe atmospheric molecular OH emission lines. We have succeeded in detecting upwards of 27 lines, and demonstrated the practicality of the IPS device for astronomy. Furthermore, we present a laboratory characterization of the device, which is a modified version of a commercial arrayed-waveguide grating multiplexer. We measure the spectral resolution full-width-half-maximum to be 0.75 +/- 0.05 nm (giving R = lambda/deltalambda = 2100 +/- 150 at 1500 nm). We find the free spectral range to be 57.4 +/- 0.6 nm and the peak total efficiency to be approximately 65%. Finally, we briefly discuss the future steps required to realize an astronomical instrument based on this technology concept.

  7. Onboard Autonomy and Ground Operations Automation for the Intelligent Payload Experiment (IPEX) CubeSat Mission

    NASA Technical Reports Server (NTRS)

    Chien, Steve; Doubleday, Joshua; Ortega, Kevin; Tran, Daniel; Bellardo, John; Williams, Austin; Piug-Suari, Jordi; Crum, Gary; Flatley, Thomas

    2012-01-01

    The Intelligent Payload Experiment (IPEX) is a cubesat manifested for launch in October 2013 that will flight validate autonomous operations for onboard instrument processing and product generation for the Intelligent Payload Module (IPM) of the Hyperspectral Infra-red Imager (HyspIRI) mission concept. We first describe the ground and flight operations concept for HyspIRI IPM operations. We then describe the ground and flight operations concept for the IPEX mission and how that will validate HyspIRI IPM operations. We then detail the current status of the mission and outline the schedule for future development.

  8. EMERGENCE OF GRANULAR-SIZED MAGNETIC BUBBLES THROUGH THE SOLAR ATMOSPHERE. III. THE PATH TO THE TRANSITION REGION

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

    Ortiz, Ada; Hansteen, Viggo H.; Pontieu, Bart De

    2016-07-10

    We study, for the first time, the ascent of granular-sized magnetic bubbles from the solar photosphere through the chromosphere into the transition region and above. Such events occurred in a flux emerging region in NOAA 11850 on 2013 September 25. During that time, the first co-observing campaign between the Swedish 1-m Solar Telescope (SST) and the Interface Region Imaging Spectrograph (IRIS) spacecraft was carried out. Simultaneous observations of the chromospheric H α 656.28 nm and Ca ii 854.2 nm lines, plus the photospheric Fe i 630.25 nm line, were made with the CRISP spectropolarimeter at the Spitzer Space Telescope (more » SST ) reaching a spatial resolution of 0.″14. At the same time, IRIS was performing a four-step dense raster of the emerging flux region, taking slit jaw images at 133 (C ii, transition region), 140 (Si iv, transition region), 279.6 (Mg ii k, core, upper chromosphere), and 283.2 nm (Mg ii k, wing, photosphere). Spectroscopy of several lines was performed by the IRIS spectrograph in the far- and near-ultraviolet, of which we have used the Si iv 140.3 and the Mg ii k 279.6 nm lines. Coronal images from the Atmospheric Imaging Assembly of the Solar Dynamics Observatory were used to investigate the possible coronal signatures of the flux emergence events. The photospheric and chromospheric properties of small-scale emerging magnetic bubbles have been described in detail in Ortiz et al. Here we are able to follow such structures up to the transition region. We describe the properties, including temporal delays, of the observed flux emergence in all layers. We believe this may be an important mechanism of transporting energy and magnetic flux from subsurface layers to the transition region and corona.« less

  9. Propagating wave in active region-loops, located over the solar disk observed by the Interface Region Imaging Spectrograph

    NASA Astrophysics Data System (ADS)

    Zhang, B.; Hou, Y. J.; Zhang, J.

    2018-03-01

    Aims: We aim to ascertain the physical parameters of a propagating wave over the solar disk detected by the Interface Region Imaging Spectrograph (IRIS). Methods: Using imaging data from the IRIS and the Solar Dynamic Observatory (SDO), we tracked bright spots to determine the parameters of a propagating transverse wave in active region (AR) loops triggered by activation of a filament. Deriving the Doppler velocity of Si IV line from spectral observations of IRIS, we have determined the rotating directions of active region loops which are relevant to the wave. Results: On 2015 December 19, a filament was located on the polarity inversion line of the NOAA AR 12470. The filament was activated and then caused a C1.1 two-ribbon flare. Between the flare ribbons, two rotation motions of a set of bright loops were observed to appear in turn with opposite directions. Following the end of the second rotation, a propagating wave and an associated transverse oscillation were detected in these bright loops. In 1400 Å channel, there was bright material flowing along the loops in a wave-like manner, with a period of 128 s and a mean amplitude of 880 km. For the transverse oscillation, we tracked a given loop and determine the transverse positions of the tracking loop in a limited longitudinal range. In both of 1400 Å and 171 Å channels, approximately four periods are distinguished during the transverse oscillation. The mean period of the oscillation is estimated as 143 s and the displacement amplitude as between 1370 km and 690 km. We interpret these oscillations as a propagating kink wave and obtain its speed of 1400 km s-1. Conclusions: Our observations reveal that a flare associated with filament activation could trigger a kink propagating wave in active region loops over the solar disk. Movies associated to Figs. 1-4 are available at http://https://www.aanda.org

  10. Reconstruction of a helical prominence in 3D from IRIS spectra and images

    NASA Astrophysics Data System (ADS)

    Schmieder, B.; Zapiór, M.; López Ariste, A.; Levens, P.; Labrosse, N.; Gravet, R.

    2017-10-01

    Context. Movies of prominences obtained by space instruments e.g. the Solar Optical Telescope (SOT) aboard the Hinode satellite and the Interface Region Imaging Spectrograph (IRIS) with high temporal and spatial resolution revealed the tremendous dynamical nature of prominences. Knots of plasma belonging to prominences appear to travel along both vertical and horizontal thread-like loops, with highly dynamical nature. Aims: The aim of the paper is to reconstruct the 3D shape of a helical prominence observed over two and a half hours by IRIS. Methods: From the IRIS Mg II k spectra we compute Doppler shifts of the plasma inside the prominence and from the slit-jaw images (SJI) we derive the transverse field in the plane of the sky. Finally we obtain the velocity vector field of the knots in 3D. Results.We reconstruct the real trajectories of nine knots travelling along ellipses. Conclusions: The spiral-like structure of the prominence observed in the plane of the sky is mainly due to the projection effect of long arches of threads (up to 8 × 104 km). Knots run along more or less horizontal threads with velocities reaching 65 km s-1. The dominant driving force is the gas pressure. Movies associated to Figs. 1, 9, 10, and 13 are available at http://www.aanda.org

  11. SIMULTANEOUS IRIS AND HINODE/EIS OBSERVATIONS AND MODELING OF THE 2014 OCTOBER 27 X2.0 CLASS FLARE

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

    Polito, V.; Reep, J. W.; Del Zanna, G.

    We present a study of the X2-class flare which occurred on 2014 October 27 and was observed with the Interface Region Imaging Spectrograph (IRIS) and the EUV Imaging Spectrometer (EIS) on board the Hinode satellite. Thanks to the high cadence and spatial resolution of the IRIS and EIS instruments, we are able to compare simultaneous observations of the Fe xxi 1354.08 Å and Fe xxiii 263.77 Å high-temperature emission (≳10 MK) in the flare ribbon during the chromospheric evaporation phase. We find that IRIS observes completely blueshifted Fe xxi line profiles, up to 200 km s{sup −1} during the rise phase of the flare, indicatingmore » that the site of the plasma upflows is resolved by IRIS. In contrast, the Fe xxiii line is often asymmetric, which we interpret as being due to the lower spatial resolution of EIS. Temperature estimates from SDO/AIA and Hinode/XRT show that hot emission (log(T[K]) > 7.2) is first concentrated at the footpoints before filling the loops. Density-sensitive lines from IRIS and EIS give estimates of electron number density of ≳10{sup 12} cm{sup −3} in the transition region lines and 10{sup 10} cm{sup −3} in the coronal lines during the impulsive phase. In order to compare the observational results against theoretical predictions, we have run a simulation of a flare loop undergoing heating using the HYDRAD 1D hydro code. We find that the simulated plasma parameters are close to the observed values that are obtained with IRIS, Hinode, and AIA. These results support an electron beam heating model rather than a purely thermal conduction model as the driving mechanism for this flare.« less

  12. Non-Maxwellian Analysis of the Transition-region Line Profiles Observed by the Interface Region Imaging Spectrograph

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

    Dudík, Jaroslav; Dzifčáková, Elena; Polito, Vanessa

    2017-06-10

    We investigate the nature of the spectral line profiles for transition-region (TR) ions observed with the Interface Region Imaging Spectrograph (IRIS) . In this context, we analyzed an active-region observation performed by IRIS in its 1400 Å spectral window. The TR lines are found to exhibit significant wings in their spectral profiles, which can be well fitted with a non-Maxwellian κ distribution. The fit with a κ distribution can perform better than a double-Gaussian fit, especially for the strongest line, Si iv 1402.8 Å. Typical values of κ found are about 2, occurring in a majority of spatial pixels wheremore » the TR lines are symmetric, i.e., the fit can be performed. Furthermore, all five spectral lines studied (from Si iv, O iv, and S iv) appear to have the same full-width at half-maximum irrespective of whether the line is an allowed or an intercombination transition. A similar value of κ is obtained for the electron distribution by the fitting of the line intensities relative to Si iv 1402.8 Å, if photospheric abundances are assumed. The κ distributions, however, do not remove the presence of non-thermal broadening. Instead, they actually increase the non-thermal width. This is because, for κ distributions, TR ions are formed at lower temperatures. The large observed non-thermal width lowers the opacity of the Si iv line sufficiently enough for this line to become optically thin.« less

  13. THE ELECTRON DENSITY IN EXPLOSIVE TRANSITION REGION EVENTS OBSERVED BY IRIS

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

    Doschek, G. A.; Warren, H. P.; Young, P. R.

    We discuss the intensity ratio of the O iv line at 1401.16 Å to the Si iv line at 1402.77 Å in Interface Region Imaging Spectrograph ( IRIS ) spectra. This intensity ratio is important if it can be used to measure high electron densities that cannot be measured using line intensity ratios of two different O iv lines from the multiplet within the IRIS wavelength range. Our discussion is in terms of considerably earlier observations made from the Skylab manned space station and other spectrometers on orbiting spacecraft. The earlier data on the O iv and Si iv ratiomore » and other intersystem line ratios not available to IRIS are complementary to IRIS data. In this paper, we adopt a simple interpretation based on electron density. We adopt a set of assumptions and calculate the electron density as a function of velocity in the Si iv line profiles of two explosive events. At zero velocity the densities are about 2–3 × 10{sup 11} cm{sup -3}, and near 200 km s{sup -1} outflow speed the densities are about 10{sup 12} cm{sup -3}. The densities increase with outflow speed up to about 150 km s{sup -1} after which they level off. Because of the difference in the temperature of formation of the two lines and other possible effects such as non-ionization equilibrium, these density measurements do not have the precision that would be available if there were some additional lines near the formation temperature of O iv.« less

  14. MULTI-WAVELENGTH STUDY OF TRANSITION REGION PENUMBRAL SUBARCSECOND BRIGHT DOTS USING IRIS AND NST

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

    Deng, Na; Liu, Chang; Xu, Yan

    Using high-resolution transition region (TR) observations taken by the Interface Region Imaging Spectrograph ( IRIS ) mission, Tian et al. revealed numerous short-lived subarcsecond bright dots (BDs) above sunspots (mostly located in the penumbrae), which indicate yet unexplained small-scale energy releases. Moreover, whether or not these subarcsecond TR brightenings have any signature in the lower atmosphere and how they are formed are still not fully resolved. This paper presents a multi-wavelength study of the TR penumbral BDs using a coordinated observation of a near disk center sunspot with IRIS and the 1.6 m New Solar Telescope (NST) at the Bigmore » Bear Solar Observatory. NST provides high-resolution chromospheric and photospheric observations with narrowband H α imaging spectroscopy and broadband TiO images, respectively, complementary to IRIS TR observations. A total of 2692 TR penumbral BDs are identified from a 37 minute time series of IRIS 1400 Å slit-jaw images. Their locations tend to be associated more with downflowing and darker fibrils in the chromosphere, and weakly associated with bright penumbral features in the photosphere. However, temporal evolution analyses of the BDs show that there is no consistent and convincing brightening response in the chromosphere. These results are compatible with a formation mechanism of the TR penumbral BDs by falling plasma from coronal heights along more vertical and dense magnetic loops. The BDs may also be produced by small-scale impulsive magnetic reconnection taking place sufficiently high in the atmosphere that has no energy release in the chromosphere.« less

  15. PROPERTIES AND MODELING OF UNRESOLVED FINE STRUCTURE LOOPS OBSERVED IN THE SOLAR TRANSITION REGION BY IRIS

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

    Brooks, David H.; Reep, Jeffrey W.; Warren, Harry P.

    Recent observations from the Interface Region Imaging Spectrograph ( IRIS ) have discovered a new class of numerous low-lying dynamic loop structures, and it has been argued that they are the long-postulated unresolved fine structures (UFSs) that dominate the emission of the solar transition region. In this letter, we combine IRIS measurements of the properties of a sample of 108 UFSs (intensities, lengths, widths, lifetimes) with one-dimensional non-equilibrium ionization simulations, using the HYDRAD hydrodynamic model to examine whether the UFSs are now truly spatially resolved in the sense of being individual structures rather than being composed of multiple magnetic threads.more » We find that a simulation of an impulsively heated single strand can reproduce most of the observed properties, suggesting that the UFSs may be resolved, and the distribution of UFS widths implies that they are structured on a spatial scale of 133 km on average. Spatial scales of a few hundred kilometers appear to be typical for a range of chromospheric and coronal structures, and we conjecture that this could be an important clue for understanding the coronal heating process.« less

  16. The Diffuse Interstellar Cloud Experiment: a high-resolution far-ultraviolet spectrograph.

    PubMed

    Schindhelm, Eric; Beasley, Matthew; Burgh, Eric B; Green, James C

    2012-03-01

    We have designed, assembled, and launched a sounding rocket payload to perform high-resolution far-ultraviolet spectroscopy. The instrument is functionally a Cassegrain telescope followed by a modified Rowland spectrograph. The spectrograph was designed to achieve a resolving power (R=λ/δλ) of 60,000 in a compact package by adding a magnifying secondary optic. This is enabled by using a holographically ruled grating to minimize aberrations induced by the second optic. We designed the instrument to observe two stars on opposing sides of a nearby hot/cold gas interface. Obtaining spectra of the O VI doublet in absorption toward these stars can provide new insight into the processes governing hot gas in the local interstellar medium. Here we present the optical design and alignment of the telescope and spectrograph, as well as flight results. © 2012 Optical Society of America

  17. KENNEDY SPACE CENTER, FLA. - The Rotating Service Structure has been retracted at KSC's Launch Pad 39A. Discovery, the orbiter for the STS-82 mission, is ready for the launch of the second Hubble Space Telescope service mission. The payload consists of the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) that will be installed, Fine Guidance Sensor #1 (FGS-1), and the Space Telescope Imaging Spectrograph (STIS) to be installed. The STS-82 will launch with a crew of seven at 3:54 a.m. EST, Feb. 11, 1997. The launch window is 65 minutes in duration. The Mission Commander for STS-82 is Ken Bowersox. The purpose of the mission is to upgrade the scientific capabilities, service or replace aging components on the Telescope, and provide a reboost to the optimum altitude.

    NASA Image and Video Library

    1997-02-10

    KENNEDY SPACE CENTER, FLA. - The Rotating Service Structure has been retracted at KSC's Launch Pad 39A. Discovery, the orbiter for the STS-82 mission, is ready for the launch of the second Hubble Space Telescope service mission. The payload consists of the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) that will be installed, Fine Guidance Sensor #1 (FGS-1), and the Space Telescope Imaging Spectrograph (STIS) to be installed. The STS-82 will launch with a crew of seven at 3:54 a.m. EST, Feb. 11, 1997. The launch window is 65 minutes in duration. The Mission Commander for STS-82 is Ken Bowersox. The purpose of the mission is to upgrade the scientific capabilities, service or replace aging components on the Telescope, and provide a reboost to the optimum altitude.

  18. IRIS Burst Spectra Co-spatial to a Quiet-Sun Ellerman-like Brightening

    NASA Astrophysics Data System (ADS)

    Nelson, C. J.; Freij, N.; Reid, A.; Oliver, R.; Mathioudakis, M.; Erdélyi, R.

    2017-08-01

    Ellerman bombs (EBs) have been widely studied over the past two decades; however, only recently have the counterparts of these events been observed in the quiet-Sun. The aim of this article is to further understand small-scale quiet-Sun Ellerman-like brightenings (QSEBs) through research into their spectral signatures, including investigating whether the hot signatures associated with some EBs are also visible co-spatial to any QSEBs. We combine Hα and Ca II 8542 Å line scans at the solar limb with spectral and imaging data sampled by the Interface Region Imaging Spectrograph (IRIS). Twenty-one QSEBs were identified with average lifetimes, lengths, and widths measured to be around 120 s, 0.″63, and 0.″35, respectively. Three of these QSEBs displayed clear repetitive flaring through their lifetimes, comparable to the behavior of EBs in active regions. Two QSEBs in this sample occurred co-spatial to increased emission in SDO/AIA 1600 Å and IRIS slit-jaw imager 1400 Å data; however, these intensity increases were smaller than those reported co-spatially with EBs. One QSEB was also sampled by the IRIS slit during its lifetime, displaying increases in intensity in the Si IV 1393 Å and Si IV 1403 Å cores, as well as the C II and Mg II line wings, analogous to IRIS bursts (IBs). Using RADYN simulations, we are unable to reproduce the observed QSEB Hα and Ca II 8542 Å line profiles, leaving the question of the temperature stratification of QSEBs open. Our results imply that some QSEBs could be heated to transition region temperatures, suggesting that IB profiles should be observed throughout the quiet-Sun.

  19. The formation of IRIS diagnostics. III. Near-ultraviolet spectra and images

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

    Pereira, T. M. D.; Leenaarts, J.; De Pontieu, B.

    The Mg II h and k lines are the prime chromospheric diagnostics of NASA's Interface Region Imaging Spectrograph (IRIS). In the previous papers of this series, we used a realistic three-dimensional radiative magnetohydrodynamics model to calculate the h and k lines in detail and investigated how their spectral features relate to the underlying atmosphere. In this work, we employ the same approach to investigate how the h and k diagnostics fare when taking into account the finite resolution of IRIS and different noise levels. In addition, we investigate the diagnostic potential of several other photospheric lines and near-continuum regions presentmore » in the near-ultraviolet (NUV) window of IRIS and study the formation of the NUV slit-jaw images. We find that the instrumental resolution of IRIS has a small effect on the quality of the h and k diagnostics; the relations between the spectral features and atmospheric properties are mostly unchanged. The peak separation is the most affected diagnostic, but mainly due to limitations of the simulation. The effects of noise start to be noticeable at a signal-to-noise ratio (S/N) of 20, but we show that with noise filtering one can obtain reliable diagnostics at least down to a S/N of 5. The many photospheric lines present in the NUV window provide velocity information for at least eight distinct photospheric heights. Using line-free regions in the h and k far wings, we derive good estimates of photospheric temperature for at least three heights. Both of these diagnostics, in particular the latter, can be obtained even at S/Ns as low as 5.« less

  20. IRIS Burst Spectra Co-spatial to a Quiet-Sun Ellerman-like Brightening

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

    Nelson, C. J.; Erdélyi, R.; Freij, N.

    Ellerman bombs (EBs) have been widely studied over the past two decades; however, only recently have the counterparts of these events been observed in the quiet-Sun. The aim of this article is to further understand small-scale quiet-Sun Ellerman-like brightenings (QSEBs) through research into their spectral signatures, including investigating whether the hot signatures associated with some EBs are also visible co-spatial to any QSEBs. We combine H α and Ca ii 8542 Å line scans at the solar limb with spectral and imaging data sampled by the Interface Region Imaging Spectrograph ( IRIS ). Twenty-one QSEBs were identified with average lifetimes,more » lengths, and widths measured to be around 120 s, 0.″63, and 0.″35, respectively. Three of these QSEBs displayed clear repetitive flaring through their lifetimes, comparable to the behavior of EBs in active regions. Two QSEBs in this sample occurred co-spatial to increased emission in SDO /AIA 1600 Å and IRIS slit-jaw imager 1400 Å data; however, these intensity increases were smaller than those reported co-spatially with EBs. One QSEB was also sampled by the IRIS slit during its lifetime, displaying increases in intensity in the Si iv 1393 Å and Si iv 1403 Å cores, as well as the C ii and Mg ii line wings, analogous to IRIS bursts (IBs). Using RADYN simulations, we are unable to reproduce the observed QSEB H α and Ca ii 8542 Å line profiles, leaving the question of the temperature stratification of QSEBs open. Our results imply that some QSEBs could be heated to transition region temperatures, suggesting that IB profiles should be observed throughout the quiet-Sun.« less

  1. Oscillations in the 45 - 5000 MHz Radio Spectrum of the 18 April 2014 Flare

    NASA Astrophysics Data System (ADS)

    Karlický, Marian; Rybák, Ján; Monstein, Christian

    2017-07-01

    Using a new type of oscillation map, made from the radio spectra by the wavelet technique, we study the 18 April 2014 M7.3 flare (SOL2014-04-18T13:03:00L245C017). We find a quasi-periodic character of this flare with periods in the range 65 - 115 seconds. At the very beginning of this flare, in connection with the drifting pulsation structure (plasmoid ejection), we find that the 65 - 115 s oscillation phase slowly drifts towards lower frequencies, which indicates an upward propagating wave initiated at the start of the magnetic reconnection. Many periods (1 - 200 seconds) are found in the drifting pulsation structure, which documents multi-scale and multi-periodic processes. On this drifting structure, fiber bursts with a characteristic period of about one second are superimposed, whose frequency drift is similar to that of the drifting 65 - 115 s oscillation phase. We also checked periods found in this flare by the EUV Imaging Spectrometer (EIS)/ Hinode and Interface Region Imaging Spectrograph (IRIS) observations. We recognize the type III bursts (electron beams) as proposed, but their time coincidence with the EIS and IRIS peaks is not very good. The reason probably is that the radio spectrum is a whole-disk record consisting of all bursts from any location, while the EIS and IRIS peaks are emitted only from locations of slits in the EIS and IRIS observations.

  2. IEH-3 is prepared for launch on STS-95 in the MPPF

    NASA Technical Reports Server (NTRS)

    1998-01-01

    KENNEDY SPACE CENTER, FLA. -- The International Extreme Ultraviolet Hitchhiker-3 (IEH-3), one of the payloads for the STS-95 mission, is prepared for launch in the Multi-Payload Processing Facility. IEH-3 is comprised of seven experiments, including one that will be deployed on Flight Day 3. It is the small, non-recoverable Petite Amateur Navy Satellite (PANSAT) which will store and transmit digital communications. Other IEH investigations are the Solar Constant Experiment (SOLCON), Solar Extreme Ultraviolet Hitchhiker (SEH), Spectrograph/Telescope for Astronomical Research (STAR-LITE), Ultraviolet Spectrograph Telescope for Astronomical Research (UVSTAR), Consortium for Materials Development in Space Complex Autonomous Payloads (CONCAP-IV) for growing thin films via physical vapor transport, and two Get-Away Special (GAS) canister experiments. The experiments will be mounted on a hitchhiker bridge in Discovery's payload bay.

  3. MUSE, the Multi-Slit Solar Explorer

    NASA Astrophysics Data System (ADS)

    Lemen, J. R.; Tarbell, T. D.; De Pontieu, B.; Wuelser, J. P.

    2017-12-01

    The Multi-Slit Solar Explorer (MUSE) has been selected for a Phase A study for the NASA Heliophysics Small Explorer program. The science objective of MUSE is to make high spatial and temporal resolution imaging and spectral observations of the solar corona and transition region in order to probe the mechanisms responsible for energy release in the corona and understand the dynamics of the solar atmosphere. The physical processes are responsible for heating the corona, accelerating the solar wind, and the rapid release of energy in CMEs and flares. The observations will be tightly coupled to state-of-the-art numerical modeling to provide significantly improved estimates for understanding and anticipating space weather. MUSE contains two instruments: an EUV spectrograph and an EUV context imager. Both have similar spatial resolutions and leverage extensive heritage from previous high-resolution instruments such as IRIS and the HiC rocket payload. The MUSE spectrograph employs a novel multi-slit design that enables a 100x improvement in spectral scanning rates, which will reveal crucial information about the dynamics (e.g., temperature, velocities) of the physical processes that are not observable with current instruments. The MUSE investigation builds on the success of IRIS by combining numerical modeling with a uniquely capable observatory: MUSE will obtain EUV spectra and images with the highest resolution in space (1/3 arcsec) and time (1-4 s) ever achieved for the transition region and corona, along 35 slits and a large context FOV simultaneously. The MUSE consortium includes LMSAL, SAO, Stanford, ARC, HAO, GSFC, MSFC, MSU, and ITA Oslo.

  4. Solar Flare Termination Shock and Synthetic Emission Line Profiles of the Fe xxi 1354.08 Å Line

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

    Guo, Lijia; Li, Gang; Reeves, Kathy

    Solar flares are among the most energetic phenomena that occur in the solar system. In the standard solar flare model, a fast mode shock, often referred to as the flare termination shock (TS), can exist above the loop-top source of hard X-ray emissions. The existence of the TS has been recently related to spectral hardening of a flare’s hard X-ray spectra at energies >300 keV. Observations of the Fe xxi 1354.08 Å line during solar flares by the Interface Region Imaging Spectrograph ( IRIS ) spacecraft have found significant redshifts with >100 km s{sup −1}, which is consistent with amore » reconnection downflow. The ability to detect such a redshift with IRIS suggests that one may be able to use IRIS observations to identify flare TSs. Using a magnetohydrodynamic simulation to model magnetic reconnection of a solar flare and assuming the existence of a TS in the downflow of the reconnection plasma, we model the synthetic emission of the Fe xxi 1354.08 line in this work. We show that the existence of the TS in the solar flare may manifest itself in the Fe xxi 1354.08 Å line.« less

  5. ON THE CONNECTION BETWEEN PROPAGATING SOLAR CORONAL DISTURBANCES AND CHROMOSPHERIC FOOTPOINTS

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

    Bryans, P.; McIntosh, S. W.; Moortel, I. De

    2016-09-20

    The Interface Region Imaging Spectrograph ( IRIS ) provides an unparalleled opportunity to explore the (thermal) interface between the chromosphere, transition region, and the coronal plasma observed by the Atmospheric Imaging Assembly (AIA) of the Solar Dynamics Observatory ( SDO ). The SDO /AIA observations of coronal loop footpoints show strong recurring upward propagating signals—“propagating coronal disturbances” (PCDs) with apparent speeds of the order of 100–120 km s{sup −1}. That signal has a clear signature in the slit-jaw images of IRIS in addition to identifiable spectral signatures and diagnostics in the Mg iih (2803 Å) line. In analyzing the Mgmore » iih line, we are able to observe the presence of magnetoacoustic shock waves that are also present in the vicinity of the coronal loop footpoints. We see there is enough of a correspondence between the shock propagation in Mg iih, the evolution of the Si iv line profiles, and the PCD evolution to indicate that these waves are an important ingredient for PCDs. In addition, the strong flows in the jet-like features in the IRIS Si iv slit-jaw images are also associated with PCDs, such that waves and flows both appear to be contributing to the signals observed at the footpoints of PCDs.« less

  6. Propagating Disturbances in the Solar Corona and Spicular Connection

    NASA Astrophysics Data System (ADS)

    Samanta, Tanmoy; Pant, Vaibhav; Banerjee, Dipankar

    2015-12-01

    Spicules are small, hairy-like structures seen at the solar limb, mainly at chromospheric and transition region lines. They generally live for 3-10 minutes. We study these spicules in a south polar region of the Sun with coordinated observations using the Interface Region Imaging Spectrograph (IRIS) and the Atmospheric Imaging Assembly (AIA) instruments on board the Solar Dynamics Observatory. Propagating disturbances (PDs) are observed everywhere in the polar off-limb regions of the Sun at coronal heights. From these simultaneous observations, we show that the spicules and the PDs may have originated through a common process. From spacetime maps, we find that the start of the trajectory of PDs is almost cotemporal with the time of the rise of the spicular envelope as seen by IRIS slit-jaw images at 2796 and 1400 Å. During the return of spicular material, brightenings are seen in AIA 171 and 193 Å images. The quasi-periodic nature of the spicular activity, as revealed by the IRIS spectral image sequences, and its relation to coronal PDs, as recorded by the coronal AIA channels, suggest that they share a common origin. We propose that reconnection-like processes generate the spicules and waves simultaneously. The waves escape while the cool spicular material falls back.

  7. Synthetic IRIS spectra of the solar transition region: Effect of high-energy tails

    NASA Astrophysics Data System (ADS)

    Dzifčáková, E.; Vocks, C.; Dudík, J.

    2017-06-01

    Aims: The solar transition region satisfies the conditions for presence of non-Maxwellian electron energy distributions with high-energy tails at energies corresponding to the ionization potentials of many ions emitting in the extreme-ultraviolet and ultraviolet portions of the spectrum. Methods: We calculate the synthetic Si iv, O iv, and S iv spectra in the far ultraviolet channel of the Interface Region Imaging Spectrograph (IRIS). Ionization, recombination, and excitation rates are obtained by integration of the cross-sections or their approximations over the model electron distributions considering particle propagation from the hotter corona. Results: The ionization rates are significantly affected by the presence of high-energy tails. This leads to the peaks of the relative abundance of individual ions to be broadened with pronounced low-temperature shoulders. As a result, the contribution functions of individual lines observable by IRIS also exhibit low-temperature shoulders, or their peaks are shifted to temperatures an order of magnitude lower than for the Maxwellian distribution. The integrated emergent spectra can show enhancements of Si iv compared to O iv by more than a factor of two. Conclusions: The high-energy particles can have significant impact on the emergent spectra and their presence needs to be considered even in situations without strong local acceleration.

  8. THE FORMATION OF IRIS DIAGNOSTICS. II. THE FORMATION OF THE Mg II h and k LINES IN THE SOLAR ATMOSPHERE

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

    Leenaarts, J.; Pereira, T. M. D.; Carlsson, M.

    NASA's Interface Region Imaging Spectrograph (IRIS) small explorer mission will study how the solar atmosphere is energized. IRIS contains an imaging spectrograph that covers the Mg II h and k lines as well as a slit-jaw imager centered at Mg II k. Understanding the observations requires forward modeling of Mg II h and k line formation from three-dimensional (3D) radiation-magnetohydrodynamic (RMHD) models. This paper is the second in a series where we undertake this modeling. We compute the vertically emergent h and k intensity from a snapshot of a dynamic 3D RMHD model of the solar atmosphere, and investigate whichmore » diagnostic information about the atmosphere is contained in the synthetic line profiles. We find that the Doppler shift of the central line depression correlates strongly with the vertical velocity at optical depth unity, which is typically located less than 200 km below the transition region (TR). By combining the Doppler shifts of the h and k lines we can retrieve the sign of the velocity gradient just below the TR. The intensity in the central line depression is anti-correlated with the formation height, especially in subfields of a few square Mm. This intensity could thus be used to measure the spatial variation of the height of the TR. The intensity in the line-core emission peaks correlates with the temperature at its formation height, especially for strong emission peaks. The peaks can thus be exploited as a temperature diagnostic. The wavelength difference between the blue and red peaks provides a diagnostic of the velocity gradients in the upper chromosphere. The intensity ratio of the blue and red peaks correlates strongly with the average velocity in the upper chromosphere. We conclude that the Mg II h and k lines are excellent probes of the very upper chromosphere just below the TR, a height regime that is impossible to probe with other spectral lines. They also provide decent temperature and velocity diagnostics of the middle chromosphere.« less

  9. KENNEDY SPACE CENTER, FLA. - The White Room is seen at the upper left where the astronauts enter the Space Shuttle for flight. The Rotating Service Structure has been retracted at KSC's Launch Pad 39A. Discovery, the orbiter for the STS-82 mission, is ready for the launch of the second Hubble Space Telescope service mission. The payload consists of the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) that will be installed, Fine Guidance Sensor #1 (FGS-1), and the Space Telescope Imaging Spectrograph (STIS) to be installed. The STS-82 will launch with a crew of seven at 3:54 a.m. EST, Feb. 11, 1997. The launch window is 65 minutes in duration. The Mission Commander for STS-82 is Ken Bowersox. The purpose of the mission is to upgrade the scientific capabilities, service or replace aging components on the Telescope, and provide a reboost to the optimum altitude.

    NASA Image and Video Library

    1997-02-10

    KENNEDY SPACE CENTER, FLA. - The White Room is seen at the upper left where the astronauts enter the Space Shuttle for flight. The Rotating Service Structure has been retracted at KSC's Launch Pad 39A. Discovery, the orbiter for the STS-82 mission, is ready for the launch of the second Hubble Space Telescope service mission. The payload consists of the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) that will be installed, Fine Guidance Sensor #1 (FGS-1), and the Space Telescope Imaging Spectrograph (STIS) to be installed. The STS-82 will launch with a crew of seven at 3:54 a.m. EST, Feb. 11, 1997. The launch window is 65 minutes in duration. The Mission Commander for STS-82 is Ken Bowersox. The purpose of the mission is to upgrade the scientific capabilities, service or replace aging components on the Telescope, and provide a reboost to the optimum altitude.

  10. KENNEDY SPACE CENTER, FLA. - At the KSC Launch Pad 39A, two members of the payload closeout crew check equipment as the doors are just about ready to be closed. The Payload inside the bay of Discovery, the orbiter for the STS-82 mission, is ready for the launch of the second Hubble Space Telescope service mission. The payload consists of the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) that will be installed, Fine Guidance Sensor #1 (FGS-1), and the Space Telescope Imaging Spectrograph (STIS) to be installed. The STS-82 will launch with a crew of seven at 3:54 a.m. EST, Feb. 11, 1997. The launch window is 65 minutes in duration. The Mission Commander for STS-82 is Ken Bowersox. The purpose of the mission is to upgrade the scientific capabilities, service or replace aging components on the Telescope and provide a reboost to the optimum altitude.

    NASA Image and Video Library

    1997-02-07

    KENNEDY SPACE CENTER, FLA. - At the KSC Launch Pad 39A, two members of the payload closeout crew check equipment as the doors are just about ready to be closed. The Payload inside the bay of Discovery, the orbiter for the STS-82 mission, is ready for the launch of the second Hubble Space Telescope service mission. The payload consists of the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) that will be installed, Fine Guidance Sensor #1 (FGS-1), and the Space Telescope Imaging Spectrograph (STIS) to be installed. The STS-82 will launch with a crew of seven at 3:54 a.m. EST, Feb. 11, 1997. The launch window is 65 minutes in duration. The Mission Commander for STS-82 is Ken Bowersox. The purpose of the mission is to upgrade the scientific capabilities, service or replace aging components on the Telescope and provide a reboost to the optimum altitude.

  11. KENNEDY SPACE CENTER, FLA. - The Payload is seen inside of the Bay just before the doors are closed for flight at KSC's Launch Pad 39A. Discovery, the orbiter for the STS-82 mission, is ready for the launch of the second Hubble Space Telescope service mission. The payload consists of the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) that will be installed, Fine Guidance Sensor #1 (FGS-1), and the Space Telescope Imaging Spectrograph (STIS) to be installed. The STS-82 will launch with a crew of seven at 3:54 a.m. EST, Feb. 11, 1997. The launch window is 65 minutes in duration. The Mission Commander for STS-82 is Ken Bowersox. The purpose of the mission is to upgrade the scientific capabilities, service or replace aging components on the Telescope, and provide a reboost to the optimum altitude.

    NASA Image and Video Library

    1997-02-07

    KENNEDY SPACE CENTER, FLA. - The Payload is seen inside of the Bay just before the doors are closed for flight at KSC's Launch Pad 39A. Discovery, the orbiter for the STS-82 mission, is ready for the launch of the second Hubble Space Telescope service mission. The payload consists of the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) that will be installed, Fine Guidance Sensor #1 (FGS-1), and the Space Telescope Imaging Spectrograph (STIS) to be installed. The STS-82 will launch with a crew of seven at 3:54 a.m. EST, Feb. 11, 1997. The launch window is 65 minutes in duration. The Mission Commander for STS-82 is Ken Bowersox. The purpose of the mission is to upgrade the scientific capabilities, service or replace aging components on the Telescope, and provide a reboost to the optimum altitude.

  12. Constraints on active region coronal heating properties from observations and modeling of chromospheric, transition region, and coronal emission

    NASA Astrophysics Data System (ADS)

    Testa, P.; Polito, V.; De Pontieu, B.; Carlsson, M.; Reale, F.; Allred, J. C.; Hansteen, V. H.

    2017-12-01

    We investigate coronal heating properties in active region cores in non-flaring conditions, using high spatial, spectral, and temporal resolution chromospheric/transition region/coronal observations coupled with detailed modeling. We will focus, in particular, on observations with the Interface Region Imaging Spectrograph (IRIS), joint with observations with Hinode (XRT and EIS) and SDO/AIA. We will discuss how these observations and models (1D HD and 3D MHD, with the RADYN and Bifrost codes) provide useful diagnostics of the coronal heating processes and mechanisms of energy transport.

  13. Hi-C Observations of Penumbral Bright Dots: Comparison with the IRIS Results

    NASA Technical Reports Server (NTRS)

    Alpert, S. E.; Tiwari, S. K.; Moore, R. L.; Savage, S. L.; Winebarger, A. R.

    2014-01-01

    We observed bright dots (BDs) in a sunspot penumbra by using data acquired by the High Resolution Coronal Imager (Hi-C). The sizes of these BDs are on the order of 1 arcsecond (1') and are therefore hard to identify using the Atmospheric Imaging Assembly's (AIA) 0.6' pixel -1 resolution. These BDs become readily apparent with Hi-C's 0.1' pixel -1 resolution. Tian et al. (2014) found penumbral BDs in the transition region (TR) by using the Interface Region Imaging Spectrograph (IRIS). However, only a few of their dots could be associated with any enhanced brightness in AIA channels. In this work, we examine the characteristics of the penumbral BDs observed by Hi-C in a sunspot penumbra, including their sizes, lifetimes, speeds, and intensity. We also attempt to relate these BDs to the IRIS BDs. There are fewer Hi-C BDs in the penumbra than seen by IRIS, though different sunspots were studied and Hi-C had a short observation time. We use 193 A Hi-C data from July 11, 2012 which observed from 18:52:00 UT{18:56:00 UT and supplement it with data from AIA's 193 A passband to see the complete lifetime of the dots that were born before and/or lasted longer than Hi-C's 5-minute observation period. We use additional AIA passbands and compare the light curves of the BDs at different temperatures to test whether the Hi-C BDs are TR BDs. We find that most Hi-C BDs show clear movement, and of those that do, they move in a radial direction, toward or away from the sunspot umbra, sometimes doing both. BDs interact with other BDs, combining to fade away or brighten. The BDs that do not interact with other BDs tend to move less and last longer. We examine the properties of the Hi-C BDs and compare them with the IRIS BDs. Our BDs are similar to the exceptional values of the IRIS BDs: they move slower on average and their sizes and lifetimes are on the higher end of the distributions of IRIS BDs. We infer that our penumbral BDs are some of the larger BDs observed by IRIS.

  14. Comparison between the Juno Earth flyby magnetic measurements and the magnetometer package on the IRIS solar observatory

    NASA Astrophysics Data System (ADS)

    Merayo, J. M.; Connerney, J. E.; Joergensen, J. L.; Dougherty, B.

    2013-12-01

    In October 2013 the NASA's Juno New Frontier spacecraft will perform an Earth Flyby Gravity Assist. During this flyby, Juno will reach an altitude of about 600 km and the magnetometer experiment will measure the magnetic field with very high precision. In June 2013 the NASA's IRIS solar observatory was successfully launched. IRIS uses a very fine guiding telescope in order to maintain a high pointing accuracy, assisted by a very high accuracy star tracker and a science grade vector magnetometer. IRIS was placed into a Sun-synchronous orbit at about 600 km altitude by a Pegasus rocket from the Vandenberg Air Force Base in California. This platform will also allow to performing measurements of the Earth's magnetic field with very high precision, since it carries similar instrumentation as on the Swarm satellites (star trackers and magnetometer). The data recorded by the Juno magnetic experiment and the IRIS magnetometer will bring a very exciting opportunity for comparing the two experiments as well as for determining current structures during the flyby.

  15. Conversion from mutual helicity to self-helicity observed with IRIS

    NASA Astrophysics Data System (ADS)

    Li, L. P.; Peter, H.; Chen, F.; Zhang, J.

    2014-10-01

    Context. In the upper atmosphere of the Sun observations show convincing evidence for crossing and twisted structures, which are interpreted as mutual helicity and self-helicity. Aims: We use observations with the new Interface Region Imaging Spectrograph (IRIS) to show the conversion of mutual helicity into self-helicity in coronal structures on the Sun. Methods: Using far UV spectra and slit-jaw images from IRIS and coronal images and magnetograms from SDO, we investigated the evolution of two crossing loops in an active region, in particular, the properties of the Si IV line profile in cool loops. Results: In the early stage two cool loops cross each other and accordingly have mutual helicity. The Doppler shifts in the loops indicate that they wind around each other. As a consequence, near the crossing point of the loops (interchange) reconnection sets in, which heats the plasma. This is consistent with the observed increase of the line width and of the appearance of the loops at higher temperatures. After this interaction, the two new loops run in parallel, and in one of them shows a clear spectral tilt of the Si IV line profile. This is indicative of a helical (twisting) motion, which is the same as to say that the loop has self-helicity. Conclusions: The high spatial and spectral resolution of IRIS allowed us to see the conversion of mutual helicity to self-helicity in the (interchange) reconnection of two loops. This is observational evidence for earlier theoretical speculations. Movie associated with Fig. 1 and Appendix A are available in electronic form at http://www.aanda.org

  16. STRUCTURE OF PROMINENCE LEGS: PLASMA AND MAGNETIC FIELD

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

    Levens, P. J.; Labrosse, N.; Schmieder, B.

    We investigate the properties of a “solar tornado” observed on 2014 July 15, and aim to link the behavior of the plasma to the internal magnetic field structure of the associated prominence. We made multi-wavelength observations with high spatial resolution and high cadence using SDO/AIA, the Interface Region Imaging Spectrograph (IRIS) spectrograph, and the Hinode/Solar Optical Telescope (SOT) instrument. Along with spectropolarimetry provided by the Télescope Héliographique pour l’Etude du Magnétisme et des Instabilités Solaires telescope we have coverage of both optically thick emission lines and magnetic field information. AIA reveals that the two legs of the prominence are stronglymore » absorbing structures which look like they are rotating, or oscillating in the plane of the sky. The two prominence legs, which are both very bright in Ca ii (SOT), are not visible in the IRIS Mg ii slit-jaw images. This is explained by the large optical thickness of the structures in Mg ii, which leads to reversed profiles, and hence to lower integrated intensities at these locations than in the surroundings. Using lines formed at temperatures lower than 1 MK, we measure relatively low Doppler shifts on the order of ±10 km s{sup −1} in the tornado-like structure. Between the two legs we see loops in Mg ii, with material flowing from one leg to the other, as well as counterstreaming. It is difficult to interpret our data as showing two rotating, vertical structures that are unrelated to the loops. This kind of “tornado” scenario does not fit with our observations. The magnetic field in the two legs of the prominence is found to be preferentially horizontal.« less

  17. Cool Transition Region Loops Observed by the Interface Region Imaging Spectrograph

    NASA Astrophysics Data System (ADS)

    Huang, Zhenghua; Xia, Lidong; Li, Bo; Madjarska, Maria S.

    2015-09-01

    We report on the first Interface Region Imaging Spectrograph (IRIS) study of cool transition region loops, a class of loops that has received little attention in the literature. A cluster of such loops was observed on the solar disk in active region NOAA11934, in the Si iv 1402.8 Å spectral raster and 1400 Å slit-jaw images. We divide the loops into three groups and study their dynamics. The first group comprises relatively stable loops, with 382-626 km cross-sections. Observed Doppler velocities are suggestive of siphon flows, gradually changing from -10 km s-1 at one end to 20 km s-1 at the other end of the loops. Nonthermal velocities of 15 ˜ 25 km s-1 were determined. Magnetic cancellation with a rate of 1015 Mx s-1 is found at the blueshifted footpoints. These physical properties suggest that these loops are impulsively heated by magnetic reconnection, and the siphon flows play an important role in the energy redistribution. The second group corresponds to two footpoints rooted in mixed-magnetic-polarity regions, where magnetic cancellation with a rate of 1015 Mx s-1 and explosive-event line profiles with enhanced wings of up to 200 km s-1 were observed. In the third group, interaction between two cool loop systems is observed. Evidence for magnetic reconnection between the two loop systems is reflected in the explosive-event line profiles and magnetic cancellation with a rate of 3× {10}15 Mx s-1 observed in the corresponding area. The IRIS has provided opportunity for in-depth investigations of cool transition region loops. Further numerical experiments are crucial for understanding their physics and their roles in the coronal heating processes.

  18. Structure of Prominence Legs: Plasma and Magnetic Field

    NASA Astrophysics Data System (ADS)

    Levens, P. J.; Schmieder, B.; Labrosse, N.; López Ariste, A.

    2016-02-01

    We investigate the properties of a “solar tornado” observed on 2014 July 15, and aim to link the behavior of the plasma to the internal magnetic field structure of the associated prominence. We made multi-wavelength observations with high spatial resolution and high cadence using SDO/AIA, the Interface Region Imaging Spectrograph (IRIS) spectrograph, and the Hinode/Solar Optical Telescope (SOT) instrument. Along with spectropolarimetry provided by the Télescope Héliographique pour l’Etude du Magnétisme et des Instabilités Solaires telescope we have coverage of both optically thick emission lines and magnetic field information. AIA reveals that the two legs of the prominence are strongly absorbing structures which look like they are rotating, or oscillating in the plane of the sky. The two prominence legs, which are both very bright in Ca II (SOT), are not visible in the IRIS Mg II slit-jaw images. This is explained by the large optical thickness of the structures in Mg II, which leads to reversed profiles, and hence to lower integrated intensities at these locations than in the surroundings. Using lines formed at temperatures lower than 1 MK, we measure relatively low Doppler shifts on the order of ±10 km s-1 in the tornado-like structure. Between the two legs we see loops in Mg II, with material flowing from one leg to the other, as well as counterstreaming. It is difficult to interpret our data as showing two rotating, vertical structures that are unrelated to the loops. This kind of “tornado” scenario does not fit with our observations. The magnetic field in the two legs of the prominence is found to be preferentially horizontal.

  19. The Stellar-IRIS Connection: Four Years of FUV Measurements of Alpha Centauri by HST/STIS

    NASA Astrophysics Data System (ADS)

    Ayres, Thomas R.

    2014-06-01

    Since 2010 January, shortly after the miraculous repair of Hubble's Space Telescope Imaging Spectrograph (STIS) by SM4, the two sun-like stars of Alpha Centauri ("A" [G2V] and "B" [K1V]) have been recorded on a semi-annual basis utilizing STIS's far-ultraviolet (115-170 nm) medium resolution mode (about 8 km/s FWHM resolving power), jointly with an X-ray imaging study of AB by the Chandra Observatory. Both efforts are intended to assess the long-term behavior of high-energy (multimillion K) coronal, and subcoronal, processes on the two relatively low-activity solar-age dwarfs. In fact, the near-solar-twin Alpha Cen A has been mired in a coronal lull since 2005, originally recognized by XMM-Newton, and only recently has begun to climb out of the extended X-ray minimum. Meanwhile, the lower mass, lower luminosity, but coronally more active secondary has displayed a clear 8-year X-ray cycle, extending from the mid-1990's ROSAT era. The current study focuses on properties of the "transition zone" lines ( 100,000 K) of the Alpha Centauri stars, namely the bulk redshifts exhibited by the Si IV, C IV, and N V doublets; the multi-component nature of the hot-line profiles; behavior of the Fe XII 124 nm coronal forbidden line; and variability of the FUV fluxes relative to the higher-energy X-ray time series. These stellar measurements, with their high precision in wavelength and flux, complement the detailed high-spatial and high-temporal resolution spectral mapping of the solar corona and lower atmosphere being carried out by NASA's Interface Region Imaging Spectrograph (IRIS). [This work supported by GO grants 12758, 13060, and 13465 from Space Telescope Science Institute.

  20. PROPERTIES OF CHROMOSPHERIC EVAPORATION AND PLASMA DYNAMICS OF A SOLAR FLARE FROM IRIS OBSERVATIONS

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

    Sadykov, Viacheslav M.; Dominguez, Santiago Vargas; Kosovichev, Alexander G.

    The dynamics of hot chromospheric plasma of solar flares is a key to understanding the mechanisms of flare energy release and particle acceleration. A moderate M1.0 class flare of 2014 June 12, (SOL2014-06-12T21:12) was simultaneously observed by NASA's Interface Region Imaging Spectrograph (IRIS) and other spacecraft, and also by the New Solar Telescope at the BBSO. This paper presents the first part of our investigation focused on analysis of the IRIS data. Our analysis of the IRIS data in different spectral lines reveals a strong redshifted jet-like flow with a speed of ∼100 km s{sup −1} of the chromospheric material beforemore » the flare. Strong nonthermal emission of the C ii k 1334.5 Å line, formed in the chromosphere–corona transition region, is observed at the beginning of the impulsive phase in several small (with a size of ∼1″) points. It is also found that the C ii k line is redshifted across the flaring region before, during, and after the impulsive phase. A peak of integrated emission of the hot (1.1 · 10{sup 7} K) plasma in the Fe xxi 1354.1 Å line is detected approximately five minutes after the integrated emission peak of the lower temperature C ii k. A strong blueshift of the Fe xxi line across the flaring region corresponds to evaporation flows of the hot chromospheric plasma with a speed of 50 km s{sup −1}. Additional analysis of the RHESSI data supports the idea that the upper chromospheric dynamics observed by IRIS has features of “gentle” evaporation driven by heating of the solar chromosphere by accelerated electrons and by a heat flux from the flare energy release site.« less

  1. Hi-C Observations of Penumbral Bright Dots

    NASA Technical Reports Server (NTRS)

    Alpert, S. E.; Tiwari, S. K.; Moore, R. L.; Savage, S. L.; Winebarger, A. R.

    2014-01-01

    We use high-quality data obtained by the High Resolution Coronal Imager (Hi-C) to examine bright dots (BDs) in a sunspot's penumbra. The sizes of these BDs are on the order of 1 arcsecond (1") and are therefore hard to identify using the Atmospheric Imaging Assembly's (AIA) 0.6" pixel(exp -1) resolution. These BD become readily apparent with Hi-C's 0.1" pixel(exp -1) resolution. Tian et al. (2014) found penumbral BDs in the transition region (TR) by using the Interface Region Imaging Spectrograph (IRIS). However, only a few of their dots could be associated with any enhanced brightness in AIA channels. In this work, we examine the characteristics of the penumbral BDs observed by Hi-C in a sunspot penumbra, including their sizes, lifetimes, speeds, and intensity. We also attempt to find any association of these BDs to the IRIS BDs. There are fewer Hi-C BDs in the penumbra than seen by IRIS, though different sunspots were studied. We use 193 Angstroms Hi-C data from July 11, 2012 which observed from approximately 18:52:00 UT- 18:56:00 UT and supplement it with data from AIA's 193 Angstrom passband to see the complete lifetime of the dots that were born before and/or lasted longer than Hi- C's 5-minute observation period. We use additional AIA passbands and compare the light curves of the BDs at different temperatures to test whether the Hi-C BDs are TR BDs. We find that most Hi-C BDs show clear movement, and of those that do, they move in a radial direction, toward or away from the sunspot umbra. Single BDs interact with other BDs, combining to fade away or brighten. The BDs that do not interact with other BDs tend to move less. Many of the properties of our BDs are similar to the extreme values of the IRIS BDs, e.g., they move slower on average and their sizes and lifetimes are on the higher end of the IRIS BDs. We infer that our penumbral BDs are the large-scale end of the distribution of BDs observed by IRIS.

  2. Hi-C Observations of Penumbral Bright Dots

    NASA Astrophysics Data System (ADS)

    Alpert, S.; Tiwari, S. K.; Moore, R. L.; Savage, S. L.; Winebarger, A. R.

    2014-12-01

    We use high-quality data obtained by the High Resolution Coronal Imager (Hi-C) to examine bright dots (BDs) in a sunspot's penumbra. The sizes of these BDs are on the order of 1 arcsecond (1") and are therefore hard to identify using the Atmospheric Imaging Assembly's (AIA) 0.6" pixel-1 resolution. These BDs become readily apparent with Hi-C's 0.1" pixel-1 resolution. Tian et al. (2014) found penumbral BDs in the transition region (TR) by using the Interface Region Imaging Spectrograph (IRIS). However, only a few of their dots could be associated with any enhanced brightness in AIA channels. In this work, we examine the characteristics of the penumbral BDs observed by Hi-C in a sunspot penumbra, including their sizes, lifetimes, speeds, and intensity. We also attempt to relate these BDs to the IRIS BDs. There are fewer Hi-C BDs in the penumbra than seen by IRIS, though different sunspots were studied. We use 193Å Hi-C data from July 11, 2012 which observed from ~18:52:00 UT--18:56:00 UT and supplement it with data from AIA's 193Å passband to see the complete lifetime of the dots that were born before and/or lasted longer than Hi-C's 5-minute observation period. We use additional AIA passbands and compare the light curves of the BDs at different temperatures to test whether the Hi-C BDs are TR BDs. We find that most Hi-C BDs show clear movement, and of those that do, they move in a radial direction, toward or away from the sunspot umbra. Single BDs interact with other BDs, combining to fade away or brighten. The BDs that do not interact with other BDs tend to move less. Our BDs are similar to the exceptional IRIS BDs: they move slower on average and their sizes and lifetimes are on the high end of the distribution of IRIS BDs. We infer that our penumbral BDs are some of the larger BDs observed by IRIS, those that are bright enough in TR emission to be seen in the 193Å band of Hi-C.

  3. GNOSIS: a novel near-infrared OH suppression unit at the AAT

    NASA Astrophysics Data System (ADS)

    Trinh, C. Q.; Ellis, S. C.; Lawrence, J. S.; Horton, A. J.; Bland-Hawthorn, J.; Leon-Saval, S. G.; Bryant, J.; Case, S.; Colless, M.; Couch, W.; Freeman, K.; Gers, L.; Glazebrook, K.; Haynes, R.; Lee, S.; Löhmannsröben, H.-G.; Miziarski, S.; O'Byrne, J.; Rambold, W.; Roth, M. M.; Schmidt, B.; Shortridge, K.; Smedley, S.; Tinney, C. G.; Xavier, P.; Zheng, J.

    2012-09-01

    GNOSIS has provided the first on-telescope demonstration of a concept to utilize complex aperioidc fiber Bragg gratings to suppress the 103 brightest atmospheric hydroxyl emission doublets between 1.47-1.7 μm. The unit is designed to be used at the 3.9-meter Anglo-Australian Telescope (AAT) feeding the IRIS2 spectrograph. Unlike previous atmospheric suppression techniques GNOSIS suppresses the lines before dispersion. We present the results of laboratory and on-sky tests from instrument commissioning. These tests reveal excellent suppression performance by the gratings and high inter-notch throughput, which combine to produce high fidelity OH-free spectra.

  4. The third flight of the Colorado high-resolution echelle stellar spectrograph (CHESS): improvements, calibrations, and preliminary results

    NASA Astrophysics Data System (ADS)

    Kruczek, Nicholas; Nell, Nicholas; France, Kevin; Hoadley, Keri; Fleming, Brian; Kane, Robert; Ulrich, Stefan; Egan, Arika; Beatty, Dawson

    2017-08-01

    In this proceeding, we describe the scientific motivation and technical development of the Colorado HighResolution Echelle Stellar Spectrograph (CHESS), focusing on the hardware advancements and testing of components for the third launch of the payload (CHESS-3). CHESS is a far ultraviolet rocket-borne instrument designed to study the atomic-to-molecular transitions within translucent cloud regions in the interstellar medium. CHESS is an objective echelle spectrograph, which uses a mechanically-ruled echelle and a powered (f/12.4) crossdispersing grating, and is designed to achieve a resolving power R > 100,000 over the bandpass λλ 1000-1600 Å. Results from final efficiency and reflectivity measurements for the optical components of CHESS-3 are presented. An important role of sounding rocket experiments is the testing and verification of the space flight capabilities of experimental technologies. CHESS-3 utilizes a 40mm-diameter cross-strip anode microchannel plate detector fabricated by Sensor Sciences LLC, capable of achieving high spatial resolution and a high global count rate (˜1 MHz). We present pre-flight laboratory spectra and calibration results, including wavelength solution and resolving power of the instrument. The fourth launch of CHESS (CHESS-4) will demonstrate a δ-doped CCD, assembled in collaboration with the Microdevices Laboratory at JPL and Arizona State University. In support of CHESS-4, the CHESS-3 payload included a photomultiplier tube, used as a secondary confirmation of the optical alignment of the payload during flight. CHESS-3 launched on 26 June 2017 aboard NASA/CU sounding rocket mission 36.323 UG. We present initial flight results for the CHESS-3 observation of the β1 Scorpii sightline.

  5. Correction of Electron Density Profiles in the Low Ionosphere Based on the Data of Vertical Sounding with the IRI Model

    NASA Astrophysics Data System (ADS)

    Denisenko, P. F.; Maltseva, O. A.; Sotsky, V. V.

    2018-03-01

    The method of correcting the daytime vertical profiles of electron plasma frequency in the low ionosphere from International Refererence Ionosphere (IRI) model in accordance with the measured data of the virtual heights and absorption of signal radiowaves (method A1) reflected from the bottom of E-region at vertical sounding (VS) is presented. The method is based on the replacement of the IRI model profile by an approximation of analytical dependence with parameters determined according to VS data and partially by the IRI model. The method is tested by the results of four joint ground-based and rocket experiments carried out in the 1970s at midlatitudes of the European part of Russia upon the launches of high-altitude geophysical rockets of the Vertical series. It is shown that the consideration of both virtual reflection heigths and absorption makes it possible to obtain electron density distributions that show the best agreement with the rocket measurements made at most height ranges in the D- and E-regions. In additional, the obtained distributions account more adequately than the IRI model for the contributions of D- and E-regions to absorption of signals reflected above these regions.

  6. Chromospheric counterparts of solar transition region unresolved fine structure loops

    NASA Astrophysics Data System (ADS)

    Pereira, Tiago M. D.; Rouppe van der Voort, Luc; Hansteen, Viggo H.; De Pontieu, Bart

    2018-04-01

    Low-lying loops have been discovered at the solar limb in transition region temperatures by the Interface Region Imaging Spectrograph (IRIS). They do not appear to reach coronal temperatures, and it has been suggested that they are the long-predicted unresolved fine structures (UFS). These loops are dynamic and believed to be visible during both heating and cooling phases. Making use of coordinated observations between IRIS and the Swedish 1-m Solar Telescope, we study how these loops impact the solar chromosphere. We show for the first time that there is indeed a chromospheric signal of these loops, seen mostly in the form of strong Doppler shifts and a conspicuous lack of chromospheric heating. In addition, we find that several instances have a inverse Y-shaped jet just above the loop, suggesting that magnetic reconnection is driving these events. Our observations add several puzzling details to the current knowledge of these newly discovered structures; this new information must be considered in theoretical models. Two movies associated to Fig. 1 are available at http://https://www.aanda.org

  7. A First Comparison of Millimeter Continuum and Mg ii Ultraviolet Line Emission from the Solar Chromosphere

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

    Bastian, T. S.; Chintzoglou, G.; De Pontieu, B.

    We present joint observations of the Sun by the Atacama Large Millimeter/submillimeter Array (ALMA) and the Interface Region Imaging Spectrograph ( IRIS ). Both millimeter/submillimeter- λ continuum emission and ultraviolet (UV) line emission originate from the solar chromosphere and both have the potential to serve as powerful and complementary diagnostics of physical conditions in this enigmatic region of the solar atmosphere. The observations were made of a solar active region on 2015 December 18 as part of the ALMA science verification effort. A map of the Sun’s continuum emission was obtained by ALMA at a wavelength of 1.25 mm (239more » GHz). A contemporaneous map was obtained by IRIS in the Mg ii h doublet line at 2803.5 Å. While a clear correlation between the 1.25 mm brightness temperature T{sub B} and the Mg ii h line radiation temperature T {sub rad} is observed, the slope is <1, perhaps as a result of the fact that these diagnostics are sensitive to different parts of the chromosphere and that the Mg ii h line source function includes a scattering component. There is a significant difference (35%) between the mean T{sub B} (1.25 mm) and mean T {sub rad} (Mg ii). Partitioning the maps into “sunspot,” “quiet areas,” and “plage regions” we find the relation between the IRIS Mg ii h line T {sub rad} and the ALMA T {sub B} region-dependent. We suggest this may be the result of regional dependences of the formation heights of the IRIS and ALMA diagnostics and/or the increased degree of coupling between the UV source function and the local gas temperature in the hotter, denser gas in plage regions.« less

  8. THE FORMATION OF IRIS DIAGNOSTICS. VIII. IRIS OBSERVATIONS IN THE C ii 133.5 nm MULTIPLET

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

    Rathore, Bhavna; Pereira, Tiago M. D.; Carlsson, Mats

    The C ii 133.5 nm multiplet has been observed by NASA’s Interface Region Imaging Spectrograph (IRIS) in unprecedented spatial resolution. The aims of this work are to characterize these new observations of the C ii lines, place them in context with previous work, and to identify any additional value the C ii lines bring when compared with other spectral lines. We make use of wide, long exposure IRIS rasters covering the quiet Sun and an active region. Line properties such as velocity shift and width are extracted from individual spectra and analyzed. The lines have a variety of shapes (mostlymore » single-peak or double-peak), are strongest in active regions and weaker in the quiet Sun. The ratio between the 133.4 and 133.5 nm components is always less than 1.8, indicating that their radiation is optically thick in all locations. Maps of the C ii line widths are a powerful new diagnostic of chromospheric structures, and their line shifts are a robust velocity diagnostic. Compared with earlier quiet Sun observations, we find similar absolute intensities and mean line widths, but smaller redshifts; this difference can perhaps be attributed to differences in spectral resolution and spatial coverage. The C ii intensity maps are somewhat similar to those of transition region lines, but also share some features with chromospheric maps such as those from the Mg ii k line, indicating that they are formed between the upper chromosphere and transition region. C ii intensity, width, and velocity maps can therefore be used to gather additional information about the upper chromosphere.« less

  9. Are IRIS Bombs Connected to Ellerman Bombs?

    NASA Astrophysics Data System (ADS)

    Tian, Hui; Xu, Zhi; He, Jiansen; Madsen, Chad

    2016-06-01

    Recent observations by the Interface Region Imaging Spectrograph (IRIS) have revealed pockets of hot gas (˜2-8 × 104 K) potentially resulting from magnetic reconnection in the partially ionized lower solar atmosphere (IRIS bombs; IBs). Using joint observations between IRIS and the Chinese New Vacuum Solar Telescope, we have identified 10 IBs. We find that 3 are unambiguously and 3 others are possibly connected to Ellerman bombs (EBs), which show intense brightening of the extended {{{H}}}α wings without leaving an obvious signature in the {{{H}}}α core. These bombs generally reveal the following distinct properties: (1) the O IV 1401.156 Å and 1399.774 Å lines are absent or very weak; (2) the Mn I 2795.640 Å line manifests as an absorption feature superimposed on the greatly enhanced Mg II k line wing; (3) the Mg II k and h lines show intense brightening in the wings and no dramatic enhancement in the cores; (4) chromospheric absorption lines such as Ni II 1393.330 Å and 1335.203 Å are very strong; and (5) the 1700 Å images obtained with the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory reveal intense and compact brightenings. These properties support the formation of these bombs in the photosphere, demonstrating that EBs can be heated much more efficiently than previously thought. We also demonstrate that the Mg II k and h lines can be used to investigate EBs similarly to {{{H}}}α , which opens a promising new window for EB studies. The remaining four IBs obviously have no connection to EBs and they do not have the properties mentioned above, suggesting a higher formation layer, possibly in the chromosphere.

  10. The third flight of CHESS: Preliminary analysis of interstellar H2 on the β1 Sco sightline

    NASA Astrophysics Data System (ADS)

    Kruczek, Nick; France, Kevin

    2018-01-01

    We describe the scientific motivation and technical development of the Colorado High-resolution Echelle Stellar Spectrograph (CHESS), focusing on the preliminary science results for the third launch of the payload (CHESS-3). CHESS is a far ultraviolet rocket-borne instrument designed to study the atomic-to-molecular transitions within translucent cloud regions in the interstellar medium. CHESS is an objective echelle spectrograph, which uses a mechanically-ruled echelle and a powered (f/12.4) cross-dispersing grating, and is designed to achieve a resolving power R > 100,000 over the band pass λλ 1000-1600 Å. CHESS-3 launched on 14 June 2017 aboard NASA/CU sounding rocket mission 36.323 UG. The target for the flight was β1 Sco, a B1V star with a sightline that is likely sampling translucent material. We present flight results of interstellar molecular hydrogen excitation, including initial measurements of the column density and temperature, on the sightline.

  11. KENNEDY SPACE CENTER, FLA. - The Payload is seen inside of the Bay just before the doors are closed for flight at Pad 39A, Kennedy Space Center, Fla. Discovery, the orbiter for STS-82 mission, is ready for the launch of the second Hubble Space Telescope service mission. The payload consists of the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) that will be installed, Fine Guidance Sensor #1 (FGS-1), and the Space Telescope Imaging Spectrograph (STIS) to be installed. The STS-82 will launch with a crew of seven at 3:54 a.m. EST, Feb. 11, 1997. The launch window is 65 minutes in duration. The Mission Commander for STS-82 is Ken Bowersox. The purpose of the mission is to upgrade the scientific capabilities, service or replace aging components on the Telescope, and provide a reboost to the optimum altitude.

    NASA Image and Video Library

    1997-02-07

    KENNEDY SPACE CENTER, FLA. - The Payload is seen inside of the Bay just before the doors are closed for flight at Pad 39A, Kennedy Space Center, Fla. Discovery, the orbiter for STS-82 mission, is ready for the launch of the second Hubble Space Telescope service mission. The payload consists of the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) that will be installed, Fine Guidance Sensor #1 (FGS-1), and the Space Telescope Imaging Spectrograph (STIS) to be installed. The STS-82 will launch with a crew of seven at 3:54 a.m. EST, Feb. 11, 1997. The launch window is 65 minutes in duration. The Mission Commander for STS-82 is Ken Bowersox. The purpose of the mission is to upgrade the scientific capabilities, service or replace aging components on the Telescope, and provide a reboost to the optimum altitude.

  12. Rocket studies of solar corona and transition region. [X-Ray spectrometer/spectrograph telescope

    NASA Technical Reports Server (NTRS)

    Acton, L. W.; Bruner, E. C., Jr.; Brown, W. A.; Nobles, R. A.

    1979-01-01

    The XSST (X-Ray Spectrometer/Spectrograph Telescope) rocket payload launched by a Nike Boosted Black Brant was designed to provide high spectral resolution coronal soft X-ray line information on a spectrographic plate, as well as time resolved photo-electric records of pre-selected lines and spectral regions. This spectral data is obtained from a 1 x 10 arc second solar region defined by the paraboloidal telescope of the XSST. The transition region camera provided full disc images in selected spectral intervals originating in lower temperature zones than the emitting regions accessible to the XSST. A H-alpha camera system allowed referencing the measurements to the chromospheric temperatures and altitudes. Payload flight and recovery information is provided along with X-ray photoelectric and UV flight data, transition camera results and a summary of the anomalies encountered. Instrument mechanical stability and spectrometer pointing direction are also examined.

  13. Development and Flight-testing of Astronomical Instrumentation for Future NASA Astrophysics Missions

    NASA Astrophysics Data System (ADS)

    France, Kevin

    We propose a four year suborbital research program to continue the University of Colorado's efforts in the development and flight testing of instrument designs and critical path technologies for ultraviolet spectroscopy in support of future NASA Explorer, Probe-, and Flagship-class missions. This proposal builds on our existing program of high-resolution spectroscopy for the 100 - 160 nm bandpass with the development of a new high-efficiency imaging spectrograph operating in the same band. The ultimate goal of the University of Colorado ultraviolet rocket program is to develop the technical capabilities to enable a future, highly multiplexed ultraviolet spectrograph (with both high-resolution and imaging spectroscopy modes), e.g., an analog to the successful HST-STIS instrument, with an order-of-magnitude higher efficiency. We do this in the framework of a university led program where undergraduate, graduate, and postdoctoral training is paramount and cutting edge science investigations support our baseline technology development program. In the proposed effort, we will optimize our high-resolution (R > 100,000) echelle spectrograph payload (CHESS) with the first science flight of a new, large-format CCD array provided by our collaborators at JPL and Arizona State University. We will launch CHESS to study our local interstellar environment with spectral resolving power and bandpass that cannot be achieved with any suite of current or planned space missions. In parallel with the proposed science flights of CHESS, we will design, calibrate, and launch a new high-throughput imaging spectrograph (SISTINE); the first sub-arcsecond imaging, medium spectral resolution (R = 10,000), spectrograph ever flown with spectral coverage over the entire 100 - 160 nm bandpass. SISTINE incorporates several novel optical technologies that were highlighted as major hardware drivers for NASA's next large ultraviolet/optical/near-IR observatory by the 2014 Cosmic Origins Technology Report, including advanced mirror coatings with high broadband reflectivity (including > 20% efficiency gains below 115 nm), the first demonstration and flight test of these coatings on a shaped 0.5-meter telescope, and large-format, high-QE photon counting detectors. SISTINE will be launched to study the energetic radiation environment in the habitable zones around nearby low-mass exoplanet host stars, systems that are the top priority in NASA's search for the signatures of biological activity in the coming decade. SISTINE addresses the highest science priority in the 2010 Astronomy and Astrophysics Decadal Survey and is a crucial step towards meeting NASA's technology needs for future space observatories.

  14. On the Performance of Multi-Instrument Solar Flare Observations During Solar Cycle 24

    NASA Astrophysics Data System (ADS)

    Milligan, Ryan O.; Ireland, Jack

    2018-02-01

    The current fleet of space-based solar observatories offers us a wealth of opportunities to study solar flares over a range of wavelengths. Significant advances in our understanding of flare physics often come from coordinated observations between multiple instruments. Consequently, considerable efforts have been, and continue to be, made to coordinate observations among instruments ( e.g. through the Max Millennium Program of Solar Flare Research). However, there has been no study to date that quantifies how many flares have been observed by combinations of various instruments. Here we describe a technique that retrospectively searches archival databases for flares jointly observed by the Ramaty High Energy Solar Spectroscopic Imager (RHESSI), Solar Dynamics Observatory (SDO)/ EUV Variability Experiment (EVE - Multiple EUV Grating Spectrograph (MEGS)-A and -B, Hinode/( EUV Imaging Spectrometer, Solar Optical Telescope, and X-Ray Telescope), and Interface Region Imaging Spectrograph (IRIS). Out of the 6953 flares of GOES magnitude C1 or greater that we consider over the 6.5 years after the launch of SDO, 40 have been observed by 6 or more instruments simultaneously. Using each instrument's individual rate of success in observing flares, we show that the numbers of flares co-observed by 3 or more instruments are higher than the number expected under the assumption that the instruments operated independently of one another. In particular, the number of flares observed by larger numbers of instruments is much higher than expected. Our study illustrates that these missions often acted in cooperation, or at least had aligned goals. We also provide details on an interactive widget ( Solar Flare Finder), now available in SSWIDL, which allows a user to search for flaring events that have been observed by a chosen set of instruments. This provides access to a broader range of events in order to answer specific science questions. The difficulty in scheduling coordinated observations for solar-flare research is discussed with respect to instruments projected to begin operations during Solar Cycle 25, such as the Daniel K. Inouye Solar Telescope, Solar Orbiter, and Parker Solar Probe.

  15. New Window on the Universe.

    ERIC Educational Resources Information Center

    Reynolds, Ronald F.

    1984-01-01

    Describes the basic components of a space telescope that will be launched during a 1986 space shuttle mission. These components include a wide field/planetary camera, faint object spectroscope, high-resolution spectrograph, high-speed photometer, faint object camera, and fine guidance sensors. Data to be collected from these instruments are…

  16. Sounding Rocket Instrument Development at UAHuntsville/NASA MSFC

    NASA Technical Reports Server (NTRS)

    Kobayashi, Ken; Cirtain, Jonathan; Winebarger, Amy; Savage, Sabrina; Golub, Leon; Korreck, Kelly; Kuzin, Sergei; Walsh, Robert; DeForest, Craig; DePontieu, Bart; hide

    2013-01-01

    We present an overview of solar sounding rocket instruments developed jointly by NASA Marshall Space Flight Center and the University of Alabama in Huntsville. The High Resolution Coronal Imager (Hi-C) is an EUV (19.3 nm) imaging telescope which was flown successfully in July 2012. The Chromospheric Lyman-Alpha SpectroPolarimeter (CLASP) is a Lyman Alpha (121.6 nm) spectropolarimeter developed jointly with the National Astronomical Observatory of Japan and scheduled for launch in 2015. The Marshall Grazing Incidence X-ray Spectrograph is a soft X-ray (0.5-1.2 keV) stigmatic spectrograph designed to achieve 5 arcsecond spatial resolution along the slit.

  17. TIME DEPENDENT NONEQUILIBRIUM IONIZATION OF TRANSITION REGION LINES OBSERVED WITH IRIS

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

    Martínez-Sykora, Juan; Pontieu, Bart De; Hansteen, Viggo H.

    The properties of nonstatistical equilibrium ionization of silicon and oxygen ions are analyzed in this work. We focus on five solar targets (quiet Sun; coronal hole; plage; quiescent active region, AR; and flaring AR) as observed with the Interface Region Imaging Spectrograph (IRIS). IRIS is best suited for this work owing to the high cadence (up to 0.5 s), high spatial resolution (up to 0.″32), and high signal-to-noise ratios for O iv λ1401 and Si iv λ1402. We find that the observed intensity ratio between lines of three times ionized silicon and oxygen ions depends on their total intensity and that this correlationmore » varies depending on the region observed (quiet Sun, coronal holes, plage, or active regions) and on the specific observational objects present (spicules, dynamic loops, jets, microflares, or umbra). In order to interpret the observations, we compare them with synthetic profiles taken from 2D self-consistent radiative MHD simulations of the solar atmosphere, where the statistical equilibrium or nonequilibrium treatment of silicon and oxygen is applied. These synthetic observations show vaguely similar correlations to those in the observations, i.e., between the intensity ratios and their intensities, but only in the nonequilibrium case do we find that (some of) the observations can be reproduced. We conclude that these lines are formed out of statistical equilibrium. We use our time-dependent nonequilibrium ionization simulations to describe the physical mechanisms behind these observed properties.« less

  18. Southern California Disasters II

    NASA Technical Reports Server (NTRS)

    Nicholson, Heather; Todoroff, Amber L.; LeBoeuf, Madeline A.

    2015-01-01

    The USDA Forest Service (USFS) has multiple programs in place which primarily utilize Landsat imagery to produce burn severity indices for aiding wildfire damage assessment and mitigation. These indices provide widely-used wildfire damage assessment tools to decision makers. When the Hyperspectral Infrared Imager (HyspIRI) is launched in 2022, the sensor's hyperspectral resolution will support new methods for assessing natural disaster impacts on ecosystems, including wildfire damage to forests. This project used simulated HyspIRI data to study three southern California fires: Aspen, French, and King. Burn severity indices were calculated from the data and the results were quantitatively compared to the comparable USFS products currently in use. The final results from this project illustrate how HyspIRI data may be used in the future to enhance assessment of fire-damaged areas and provide additional monitoring tools for decision support to the USFS and other land management agencies.

  19. ORAC-DR: One Pipeline for Multiple Telescopes

    NASA Astrophysics Data System (ADS)

    Cavanagh, B.; Hirst, P.; Jenness, T.; Economou, F.; Currie, M. J.; Todd, S.; Ryder, S. D.

    ORAC-DR, a flexible and extensible data reduction pipeline, has been successfully used for real-time data reduction from UFTI and IRCAM (infrared cameras), CGS4 (near-infrared spectrometer), Michelle (mid-infrared imager and echelle spectrometer), at UKIRT; and SCUBA (sub-millimeter bolometer array) at JCMT. We have now added the infrared imaging spectrometers IRIS2 at the Anglo-Australian Telescope and UIST at UKIRT to the list of officially supported instruments. We also present initial integral field unit support for UIST, along with unofficial support for the imager and multi-object spectrograph GMOS at Gemini. This paper briefly describes features of the pipeline along with details of adopting ORAC-DR for other instruments on telescopes around the world.

  20. Performance of the FOS and GHRS Pt/(Cr)-Ne Hollow-cathode Lamps after their Return from Space and Comparison with Archival Data

    NASA Technical Reports Server (NTRS)

    Kerber, Florian; Lindler, Don; Bristow, Paul; Lembke, Dominik; Nave, Gillian; Reader, Joseph; Sansonetti, Craig J.; Heap, Sara R.; Rosa, Michael R.; Wood, H. John

    2006-01-01

    The Space Telescope European Coordinating Facility (ST-ECF) and National Institute of Standards and Technology (NIST) are collaborating to study hollow cathode calibration lamps as used onboard the Hubble Space Telescope (HST). As part of the STIS Calibration Enhancement (STIS-CE) Project we are trying to improve our understanding of the performance of hollow cathode lamps and the physical processes involved in their long term operation. The original flight lamps from the Faint Object Spectrograph (FOS) and the Goddard High Resolution Spectrograph (GHRS) are the only lamps that have ever been returned to Earth after extended operation in space. We have taken spectra of all four lamps using NIST s 10.7-m normal-incidence spectrograph and Fourier transform spectrometer (FTS) optimized for use in the ultraviolet (UV). These spectra, together with spectra archived from six years of on-orbit operations and pre-launch spectra, provide a unique data set - covering a period of about 20 years - for studying aging effects in these lamps. Our findings represent important lessons for the choice and design of calibration sources and their operation in future UV and optical spectrographs in space.

  1. In-orbit commissioning of the NIRSpec instrument on the James Webb Space Telescope

    NASA Astrophysics Data System (ADS)

    Böker, T.; Muzerolle, J.; Bacinski, J.; Alves de Oliveira, C.; Birkmann, S.; Ferruit, P.; Karl, H.; Lemke, R.; Lützgendorf, N.; Marston, A.; Mosner, P.; Rawle, T.; Sirianni, M.

    2016-07-01

    The James Webb Space Telescope (JWST), scheduled for launch in 2018, promises to revolutionize observational astronomy, due to its unprecedented sensitivity at near and mid-infrared wavelengths. Following launch, a ~6 month long commissioning campaign aims to verify the observatory performance. A key element in this campaign is the verification and early calibration of the four JWST science instruments, one of which is the Near-Infrared Spectrograph (NIRSpec). This paper summarizes the objectives of the NIRSpec commissioning campaign, and outlines the sequence of activities needed to achieve these objectives.

  2. Spectroscopic Observations of Magnetic Reconnection and Chromospheric Evaporation in an X-shaped Solar Flare

    NASA Astrophysics Data System (ADS)

    Li, Y.; Kelly, M.; Ding, M. D.; Qiu, J.; Zhu, X. S.; Gan, W. Q.

    2017-10-01

    We present observations of distinct UV spectral properties at different locations during an atypical X-shaped flare (SOL2014-11-09T15:32) observed by the Interface Region Imaging Spectrograph (IRIS). In this flare, four chromospheric ribbons appear and converge at an X-point where a separator is anchored. Above the X-point, two sets of non-coplanar coronal loops approach laterally and reconnect at the separator. The IRIS slit was located close to the X-point, cutting across some of the flare ribbons and loops. Near the location of the separator, the Si IV 1402.77 Å line exhibits significantly broadened line wings extending to 200 km s-1 with an unshifted line core. These spectral features suggest the presence of bidirectional flows possibly related to the separator reconnection. While at the flare ribbons, the hot Fe xxi 1354.08 Å line shows blueshifts and the cool Si IV 1402.77 Å, C II 1335.71 Å, and Mg II 2803.52 Å lines show evident redshifts up to a velocity of 80 km s-1, which are consistent with the scenario of chromospheric evaporation/condensation.

  3. High-resolution Observation of Moving Magnetic Features in Active Regions

    NASA Astrophysics Data System (ADS)

    Li, Qin; Deng, Na; Jing, Ju; Wang, Haimin

    2017-08-01

    Moving magnetic features (MMFs) are small photospheric magnetic elements that emerge and move outward toward the boundary of moat regions mostly during a sunspot decaying phase, in a serpent wave-like magnetic topology. Studies of MMFs and their classification (e.g., unipolar or bipolar types) strongly rely on the high spatiotemporal-resolution observation of photospheric magnetic field. In this work, we present a detailed observation of a sunspot evolution in NOAA active region (AR) 12565, using exceptionally high resolution Halpha images from the 1.6 New Solar telescope (NST) at Big Bear Solar Observatory (BBSO) and the UV images from the Interface Region Imaging Spectrograph (IRIS). The spectropolarimetric measurements of photospheric magnetic field are obtained from the NST Near InfraRed Imaging Spectropolarimeter (NIRIS) at Fe I 1.56 um line. We investigate the horizontal motion of the classified MMFs and discuss the clustering patterns of the geometry and motion of the MMFs. We estimate the rate of flux generation by appearance of MMFs and the role MMFs play in sunspot decaying phase. We also study the interaction between the MMFs and the existing magnetic field features and its response to Ellerman bombs and IRIS bombs respectively at higher layers.

  4. Spectroscopic Observations of Magnetic Reconnection and Chromospheric Evaporation in an X-shaped Solar Flare

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

    Li, Y.; Gan, W. Q.; Kelly, M.

    We present observations of distinct UV spectral properties at different locations during an atypical X-shaped flare (SOL2014-11-09T15:32) observed by the Interface Region Imaging Spectrograph ( IRIS ). In this flare, four chromospheric ribbons appear and converge at an X-point where a separator is anchored. Above the X-point, two sets of non-coplanar coronal loops approach laterally and reconnect at the separator. The IRIS slit was located close to the X-point, cutting across some of the flare ribbons and loops. Near the location of the separator, the Si iv 1402.77 Å line exhibits significantly broadened line wings extending to 200 km s{supmore » −1} with an unshifted line core. These spectral features suggest the presence of bidirectional flows possibly related to the separator reconnection. While at the flare ribbons, the hot Fe xxi 1354.08 Å line shows blueshifts and the cool Si iv 1402.77 Å, C ii 1335.71 Å, and Mg ii 2803.52 Å lines show evident redshifts up to a velocity of 80 km s{sup −1}, which are consistent with the scenario of chromospheric evaporation/condensation.« less

  5. TEMPORAL EVOLUTION OF MULTIPLE EVAPORATING RIBBON SOURCES IN A SOLAR FLARE

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

    Graham, D. R.; Cauzzi, G., E-mail: dgraham@arcetri.astro.it

    2015-07-10

    We present new results from the Interface Region Imaging Spectrograph (IRIS) showing the dynamic evolution of chromospheric evaporation and condensation in a flare ribbon, with the highest temporal and spatial resolution to date. IRIS observed the entire impulsive phase of the X-class flare SOL2014-09-10T17:45 using a 9.4 s cadence “sit-and-stare” mode. As the ribbon brightened successively at new positions along the slit, a unique impulsive phase evolution was observed for many tens of individual pixels in both coronal and chromospheric lines. Each activation of a new footpoint displays the same initial coronal upflows of up to ∼300 km s{sup −1}more » and chromospheric downflows up to 40 km s{sup −1}. Although the coronal flows can be delayed by over 1 minute with respect to those in the chromosphere, the temporal evolution of flows is strikingly similar between all pixels and consistent with predictions from hydrodynamic flare models. Given the large sample of independent footpoints, we conclude that each flaring pixel can be considered a prototypical, “elementary” flare kernel.« less

  6. Launch of Space Shuttle Atlantis / STS-125 Mission

    NASA Image and Video Library

    2009-05-11

    STS125-S-050 (11 May 2009) --- The launch of Space Shuttle Atlantis from launch pad 39A at NASA's Kennedy Space Center in Florida is viewed from behind launch pad 39B. On pad 39B is Space Shuttle Endeavour, which can launch, if needed, for rescue of Atlantis? crew during its STS-125 mission to service NASA?s Hubble Space Telescope. Liftoff of Atlantis was on time at 2:01 p.m. (EDT) on May 11, 2009. Onboard are astronauts Scott Altman, commander; Gregory C. Johnson, pilot; Michael Good, Megan McArthur, John Grunsfeld, Mike Massimino and Andrew Feustel, all mission specialists. Atlantis' 11-day flight will include five spacewalks to refurbish and upgrade the telescope with state-of-the-art science instruments that will expand Hubble's capabilities and extend its operational lifespan through at least 2014. The payload includes a Wide Field Camera 3, Fine Guidance Sensor and the Cosmic Origins Spectrograph.

  7. Launch of Space Shuttle Atlantis / STS-125 Mission

    NASA Image and Video Library

    2009-05-11

    STS125-S-057 (11 May 2009) --- The launch of Space Shuttle Atlantis from launch pad 39A at NASA's Kennedy Space Center in Florida is viewed from behind launch pad 39B. On pad 39B is Space Shuttle Endeavour, which can launch, if needed, for rescue of Atlantis? crew during its STS-125 mission to service NASA?s Hubble Space Telescope. Liftoff of Atlantis was on time at 2:01 p.m. (EDT) on May 11, 2009. Onboard are astronauts Scott Altman, commander; Gregory C. Johnson, pilot; Michael Good, Megan McArthur, John Grunsfeld, Mike Massimino and Andrew Feustel, all mission specialists. Atlantis' 11-day flight will include five spacewalks to refurbish and upgrade the telescope with state-of-the-art science instruments that will expand Hubble's capabilities and extend its operational lifespan through at least 2014. The payload includes a Wide Field Camera 3, Fine Guidance Sensor and the Cosmic Origins Spectrograph.

  8. The Formation of IRIS Diagnostics. IX. The Formation of the C i 135.58 NM Line in the Solar Atmosphere

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

    Lin, Hsiao-Hsuan; Carlsson, Mats; Leenaarts, Jorrit, E-mail: mats.carlsson@astro.uio.no, E-mail: jorrit.leenaarts@astro.su.se

    The C i 135.58 nm line is located in the wavelength range of NASA’s Interface Region Imaging Spectrograph ( IRIS ) small explorer mission. We study the formation and diagnostic potential of this line by means of non local-thermodynamic-equilibrium modeling, employing both 1D and 3D radiation-magnetohydrodynamic models. The C i/C ii ionization balance is strongly influenced by photoionization by Ly α emission. The emission in the C i 135.58 nm line is dominated by a recombination cascade and the line forming region is optically thick. The Doppler shift of the line correlates strongly with the vertical velocity in its linemore » forming region, which is typically located at 1.5 Mm height. With IRIS , the C i 135.58 nm line is usually observed together with the O i 135.56 nm line, and from the Doppler shift of both lines, we obtain the velocity difference between the line forming regions of the two lines. From the ratio of the C i/O i line core intensity, we can determine the distance between the C i and the O i forming layers. Combined with the velocity difference, the velocity gradient at mid-chromospheric heights can be derived. The C i/O i total intensity line ratio is correlated with the inverse of the electron density in the mid-chromosphere. We conclude that the C i 135.58 nm line is an excellent probe of the middle chromosphere by itself, and together with the O i 135.56 nm line the two lines provide even more information, which complements other powerful chromospheric diagnostics of IRIS such as the Mg ii h and k lines and the C ii lines around 133.5 nm.« less

  9. First High-resolution Spectroscopic Observations by IRIS of a Fast, Helical Prominence Eruption Associated with a Coronal Mass Ejection

    NASA Astrophysics Data System (ADS)

    Liu, W.; De Pontieu, B.; Okamoto, T. J.; Vial, J. C.; Title, A. M.; Antolin, P.; Berger, T. E.; Uitenbroek, H.

    2014-12-01

    High-resolution spectroscopic observations of prominence eruptions and associated coronal mass ejections (CMEs) are rare but can provide valuable plasma and energy diagnostics. New opportunities have recently become available with the advent of the Interface Region Imaging Spectrograph (IRIS) mission equipped with high resolution of 0.33-0.4 arcsec in space and 1 km/s in velocity, together with the Hinode Solar Optical Telescope of 0.2 arcsec spatial resolution. We report the first result of joint IRIS-Hinode observations of a spectacular prominence eruption occurring on 2014-May-09. IRIS detected a maximum redshift of 450 km/s, which, combined with the plane-of-sky speed of 800 km/s, gives a large velocity vector of 920 km/s at 30 degrees from the sky plane. This direction agrees with the source location at 30 degrees behind the limb observed by STEREO-A and indicates a nearly vertical ejection. We found two branches of redshifts separated by 200 km/s appearing in all strong lines at chromospheric to transition-region temperatures, including Mg II k/h, C II, and Si IV, suggesting a hollow, rather than solid, cone in the velocity space of the ejected material. Opposite blue- and redshifts on the two sides of the prominence exhibit corkscrew variations both in space and time, suggestive of unwinding rotations of a left-handed helical flux rope. Some erupted material returns as nearly streamline flows, exhibiting distinctly narrow line widths (~10 km/s), about 50% of those of the nearby coronal rain at the apexes of coronal loops, where the rain material is initially formed out of cooling condensation. We estimate the mass and kinetic energy of the ejected and returning material and compare them with those of the associated CME. We will discuss the implications of these observations for CME initiation mechanisms.

  10. Hi-C OBSERVATIONS OF SUNSPOT PENUMBRAL BRIGHT DOTS

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

    Alpert, Shane E.; Tiwari, Sanjiv K.; Moore, Ronald L.

    We report observations of bright dots (BDs) in a sunspot penumbra using High Resolution Coronal Imager (Hi-C) data in 193 Å and examine their sizes, lifetimes, speeds, and intensities. The sizes of the BDs are on the order of 1″ and are therefore hard to identify in the Atmospheric Imaging Assembly (AIA) 193 Å images, which have a 1.″2 spatial resolution, but become readily apparent with Hi-C's spatial resolution, which is five times better. We supplement Hi-C data with data from AIA's 193 Å passband to see the complete lifetime of the BDs that appeared before and/or lasted longer thanmore » Hi-C's three-minute observation period. Most Hi-C BDs show clear lateral movement along penumbral striations, either toward or away from the sunspot umbra. Single BDs often interact with other BDs, combining to fade away or brighten. The BDs that do not interact with other BDs tend to have smaller displacements. These BDs are about as numerous but move slower on average than Interface Region Imaging Spectrograph (IRIS) BDs, which was recently reported by Tian et al., and the sizes and lifetimes are on the higher end of the distribution of IRIS BDs. Using additional AIA passbands, we compare the light curves of the BDs to test whether the Hi-C BDs have transition region (TR) temperatures like those of the IRIS BDs. The light curves of most Hi-C BDs peak together in different AIA channels, indicating that their temperatures are likely in the range of the cooler TR (1−4 × 10{sup 5} K).« less

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

    Costa, Fatima Rubio da; Petrosian, Vahé; Kleint, Lucia

    Spectroscopic observations of solar flares provide critical diagnostics of the physical conditions in the flaring atmosphere. Some key features in observed spectra have not yet been accounted for in existing flare models. Here we report a data-driven simulation of the well-observed X1.0 flare on 2014 March 29 that can reconcile some well-known spectral discrepancies. We analyzed spectra of the flaring region from the Interface Region Imaging Spectrograph ( IRIS ) in Mg ii h and k, the Interferometric BIdimensional Spectropolarimeter at the Dunn Solar Telescope (DST/IBIS) in H α 6563 Å and Ca ii 8542 Å, and the Reuven Ramatymore » High Energy Solar Spectroscope Imager ( RHESSI ) in hard X-rays. We constructed a multithreaded flare loop model and used the electron flux inferred from RHESSI data as the input to the radiative hydrodynamic code RADYN to simulate the atmospheric response. We then synthesized various chromospheric emission lines and compared them with the IRIS and IBIS observations. In general, the synthetic intensities agree with the observed ones, especially near the northern footpoint of the flare. The simulated Mg ii line profile has narrower wings than the observed one. This discrepancy can be reduced by using a higher microturbulent velocity (27 km s{sup −1}) in a narrow chromospheric layer. In addition, we found that an increase of electron density in the upper chromosphere within a narrow height range of ≈800 km below the transition region can turn the simulated Mg ii line core into emission and thus reproduce the single peaked profile, which is a common feature in all IRIS flares.« less

  12. Synchronized observations of bright points from the solar photosphere to the corona

    NASA Astrophysics Data System (ADS)

    Tavabi, Ehsan

    2018-05-01

    One of the most important features in the solar atmosphere is the magnetic network and its relationship to the transition region (TR) and coronal brightness. It is important to understand how energy is transported into the corona and how it travels along the magnetic field lines between the deep photosphere and chromosphere through the TR and corona. An excellent proxy for transportation is the Interface Region Imaging Spectrograph (IRIS) raster scans and imaging observations in near-ultraviolet (NUV) and far-ultraviolet (FUV) emission channels, which have high time, spectral and spatial resolutions. In this study, we focus on the quiet Sun as observed with IRIS. The data with a high signal-to-noise ratio in the Si IV, C II and Mg II k lines and with strong emission intensities show a high correlation with TR bright network points. The results of the IRIS intensity maps and dopplergrams are compared with those of the Atmospheric Imaging Assembly (AIA) and Helioseismic and Magnetic Imager (HMI) instruments onboard the Solar Dynamical Observatory (SDO). The average network intensity profiles show a strong correlation with AIA coronal channels. Furthermore, we applied simultaneous observations of the magnetic network from HMI and found a strong relationship between the network bright points in all levels of the solar atmosphere. These features in the network elements exhibited regions of high Doppler velocity and strong magnetic signatures. Plenty of corona bright points emission, accompanied by the magnetic origins in the photosphere, suggest that magnetic field concentrations in the network rosettes could help to couple the inner and outer solar atmosphere.

  13. The James Webb Space Telescope: Contamination Control and Materials

    NASA Technical Reports Server (NTRS)

    Stewart, Elaine M.; Wooldridge, Eve M.

    2017-01-01

    The James Webb Space Telescope (JWST), expected to launch in 2018 or early 2019, will be the premier observatory for astronomers worldwide. It is optimized for infrared wavelengths and observation from up to 1 million miles from Earth. JWST includes an Integrated Science Instrument Module (ISIM) containing the four main instruments used to observe deep space: Near-Infrared Camera (NIRCam), Near-Infrared Spectrograph (NIRSpec), Mid-Infrared Instrument (MIRI), and Fine Guidance Sensor/Near InfraRed Imager and Slitless Spectrograph (FGS/NIRISS). JWST is extremely sensitive to contamination directly resulting in degradation in performance of the telescope. Contamination control has been an essential focus of this mission since the beginning of this observatory. A particular challenge has been contamination challenges in vacuum chamber operations.

  14. KSC-08pd2189

    NASA Image and Video Library

    2008-07-29

    CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center, workers from NASA's Goddard Space Flight Center roll the Cosmic Origins Spectrograph, or COS, into the clean room of the Payload Hazardous Servicing Facility. The COS will be installed on the Hubble Space Telescope on space shuttle Atlantis' STS-125 mission. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. COS's far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of STS-125 is targeted for Oct. 8. Photo credit: NASA/Jack Pfaller

  15. Discovery with RSS retracted

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The Rotating Service Structure has been retracted at Pad 39A. Discovery, the Space Shuttle for STS-82 Mission is ready for the launch of the second Hubble Space Telescope service mission. The payload consists of the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Which will be installed, the Fine Guidance Sensor #1 (FGS-1) and the Space Telescope Imaging Spectrograph (STIS) which will be installed. STS-82 will launch with a crew of seven at 3:54 a.m. February 11, 1997. The launch window is 65 minutes. The Mission Commander for STS-82 is Ken Bowersox. The purpose of the mission is to upgrade the scientific capabilities, service or replace aging components on the Telescope and provide a reboost to the optimum altitude.

  16. Science with 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. The science goals for JWST include the formation of the first stars and galaxies in the early universe; the chemical, morphological and dynamical buildup of galaxies and the formation of stars and planetary systems. Recently, the goals have expanded to include studies of dark energy, dark matter, active galactic nuclei, 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 Slitiess 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. Recent progress includes the completion of the mirrors, the delivery of the first flight instrument(s) and the start of the integration and test phase.

  17. 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 (SDK) telescope launched into orbit around the second Earth-Sun Lagrange point. It is a partnership of NASA with the European and Canadian Space Agencies. The science goals for JWST include the formation of the first stars and galaxies in the early universe; the chemical, morphological and dynamical buildup of galaxies and the formation of stars and planetary systems. Recently, the goals have expanded to include studies of dark energy, dark matter, active galactic nuclei, 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 S 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. Recent progress includes the completion of the mirrors, the delivery of the first flight instruments and the start of the integration and test phase.

  18. 2013: A Year in Space

    NASA Image and Video Library

    2014-01-24

    2013 was a big year for Ames Research Center's space exploration programs, including several new launches, and continuing a long history of cutting-edge innovations. Projects listed include: LADEE, IRIS, Kepler, PhoneSat, TechEdSat, NLAS, K10 Rover, Seedling Growth-1, Cell Biology Tech Demonstration, ADEPT, Spaceloft 7 and 8, CheMin, MSL, MRO, Bion-M1, Pioneer 11.

  19. New developments in instrumentation at the W. M. Keck Observatory

    NASA Astrophysics Data System (ADS)

    Adkins, Sean M.; Armandroff, Taft E.; Fitzgerald, Michael P.; Johnson, James; Larkin, James E.; Lewis, Hilton A.; Martin, Christopher; Matthews, Keith Y.; Prochaska, J. X.; Wizinowich, Peter

    2014-07-01

    The W. M. Keck Observatory continues to develop new capabilities in support of our science driven strategic plan which emphasizes leadership in key areas of observational astronomy. This leadership is a key component of the scientific productivity of our observing community and depends on our ability to develop new instrumentation, upgrades to existing instrumentation, and upgrades to supporting infrastructure at the observatory. In this paper we describe the as measured performance of projects completed in 2014 and the expected performance of projects currently in the development or construction phases. Projects reaching completion in 2014 include a near-IR tip/tilt sensor for the Keck I adaptive optics system, a new center launch system for the Keck II laser guide star facility, and NIRES, a near-IR Echelle spectrograph for the Keck II telescope. Projects in development include a new seeing limited integral field spectrograph for the visible wavelength range called the Keck Cosmic Web Imager, a deployable tertiary mirror for the Keck I telescope, upgrades to the spectrograph detector and the imager of the OSIRIS instrument, and an upgrade to the telescope control systems on both Keck telescopes.

  20. KSC-98pc1086

    NASA Image and Video Library

    1998-09-14

    KENNEDY SPACE CENTER, FLA. The International Extreme Ultraviolet Hitchhiker-3 (IEH-3), one of the payloads for the STS-95 mission, is prepared for launch in the Multi-Payload Processing Facility. IEH-3 is comprised of seven experiments, including one that will be deployed on Flight Day 3. It is the small, non-recoverable Petite Amateur Navy Satellite (PANSAT) which will store and transmit digital communications. Other IEH investigations are the Solar Constant Experiment (SOLCON), Solar Extreme Ultraviolet Hitchhiker (SEH), Spectrograph/Telescope for Astronomical Research (STAR-LITE), Ultraviolet Spectrograph Telescope for Astronomical Research (UVSTAR), Consortium for Materials Development in Space Complex Autonomous Payloads (CONCAP-IV) for growing thin films via physical vapor transport, and two Get-Away Special (GAS) canister experiments. The experiments will be mounted on a hitchhiker bridge in Discovery's payload bay

  1. Ionospheric Observations During a Geomagnetic Storm from LITES on the ISS

    NASA Astrophysics Data System (ADS)

    Finn, S. C.; Stephan, A. W.; Cook, T.; Budzien, S. A.; Chakrabarti, S.; Erickson, P. J.; Geddes, G.

    2017-12-01

    The Limb-Imaging Ionospheric and Thermospheric Extreme-Ultraviolet Spectrograph (LITES) is an extreme-ultraviolet imaging spectrograph that launched in February 2017 and was installed on the International Space Station (ISS). LITES is limb-viewing ( 150 - 350 km tangent altitude) and measures airglow emissions from 60 - 140 nm with 0.2° angular and 1 nm spectral resolutions. We present early LITES results of observations during a G2 geomagnetic storm in April 2017. In addition to LITES data, we will show complementary ground-based incoherent scatter radar (ISR) observations from Millstone Hill during this storm. The combination of LITES EUV space-based observations with the ground-based radio data is an example of the capability of campaign-style measurements of the ionosphere-thermosphere system using multiwavelength ground- and space-based instruments.

  2. KSC-08pd2182

    NASA Image and Video Library

    2008-07-29

    CAPE CANAVERAL, Fla. – In the airlock of the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, workers from NASA's Goddard Space Flight Center remove the top from the transportation canister in which the Cosmic Origins Spectrograph, or COS, arrived. The COS will be installed on the Hubble Space Telescope on space shuttle Atlantis' STS-125 mission. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. COS's far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of STS-125 is targeted for Oct. 8. Photo credit: NASA/Jack Pfaller

  3. KSC-08pd2190

    NASA Image and Video Library

    2008-07-29

    CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center, workers from NASA's Goddard Space Flight Center roll the Cosmic Origins Spectrograph, or COS, into position in the clean room of the Payload Hazardous Servicing Facility for instrument testing. The COS will be installed on the Hubble Space Telescope on space shuttle Atlantis' STS-125 mission. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. COS's far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of STS-125 is targeted for Oct. 8. Photo credit: NASA/Jack Pfaller

  4. KSC-08pd2185

    NASA Image and Video Library

    2008-07-29

    CAPE CANAVERAL, Fla. – In the airlock of the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, workers from NASA's Goddard Space Flight Center prepare to lift the Cosmic Origins Spectrograph, or COS, from its transportation canister. The COS will be installed on the Hubble Space Telescope on space shuttle Atlantis' STS-125 mission. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. COS's far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of STS-125 is targeted for Oct. 8. Photo credit: NASA/Jack Pfaller

  5. KSC-08pd2181

    NASA Image and Video Library

    2008-07-29

    CAPE CANAVERAL, Fla. – In the airlock of the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, workers from NASA's Goddard Space Flight Center open the transportation canister in which the Cosmic Origins Spectrograph, or COS, is protected. The COS will be installed on the Hubble Space Telescope on space shuttle Atlantis' STS-125 mission. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. COS's far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of STS-125 is targeted for Oct. 8. Photo credit: NASA/Jack Pfaller

  6. KSC-08pd2184

    NASA Image and Video Library

    2008-07-29

    CAPE CANAVERAL, Fla. – In the airlock of the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, workers from NASA's Goddard Space Flight Center prepare to remove the Cosmic Origins Spectrograph, or COS, from its transportation canister. The COS will be installed on the Hubble Space Telescope on space shuttle Atlantis' STS-125 mission. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. COS's far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of STS-125 is targeted for Oct. 8. Photo credit: NASA/Jack Pfaller

  7. KSC-08pd2180

    NASA Image and Video Library

    2008-07-29

    CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center, workers from NASA's Goddard Space Flight Center receive the Cosmic Origins Spectrograph, or COS, secured in its transportation canister, in the airlock of the Payload Hazardous Servicing Facility. The COS will be installed on the Hubble Space Telescope on space shuttle Atlantis' STS-125 mission. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. COS's far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of STS-125 is targeted for Oct. 8. Photo credit: NASA/Jack Pfaller

  8. KSC-08pd2183

    NASA Image and Video Library

    2008-07-29

    CAPE CANAVERAL, Fla. – In the airlock of the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, workers from NASA's Goddard Space Flight Center examine the Cosmic Origins Spectrograph, or COS, after the top from its transportation canister is removed. The COS will be installed on the Hubble Space Telescope on space shuttle Atlantis' STS-125 mission. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. COS's far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of STS-125 is targeted for Oct. 8. Photo credit: NASA/Jack Pfaller

  9. Spectroscopic Characterisation of Microlensing Events: Towards a New Interpretation of OGLE-2011-BLG-0417

    NASA Technical Reports Server (NTRS)

    Santerne, A.; Beaulieu, J.-P.; Rojas Ayala, B.; Boisse, I.; Schlawin, E.; Almenara, J.-M.; Batista, V.; Bennett, D.; Diaz, R. F.; Figueira, P.; hide

    2016-01-01

    The microlensing event OGLE-2011-BLG-0417 is an exceptionally bright lens binary that was predicted to present radial velocity variation at the level of several km s1. Pioneer radial velocity follow-up observations with the UVES spectrograph at the ESOVLT of this system clearly ruled out the large radial velocity variation, leaving a discrepancy between the observation and the prediction. In this paper, we further characterise the microlensing system by analysing its spectral energy distribution (SED) derived using the UVES spectrum and new observations with the ARCoIRIS (CTIO) near-infrared spectrograph and the Keck adaptive optics instrumentNIRC2 in the J, H, and Ks-bands. We determine the mass and distance of the stars independently from the microlensing modelling. We find that the SED is compatible with a giant star in the Galactic bulge and a foreground star with a mass of 0.94 +/- 0.09 M solar mass at a distance of 1.07 +/- 0.24 kpc. We find that this foreground star is likely the lens. Its parameters are not compatible with the onespreviously reported in the literature (0.52 +/- 0.04 M solar mass at 0.95 +/- 0.06 kpc), based on the microlensing light curve. A thoughtful reanalysis of the microlensing event is mandatory to fully understand the reason of this new discrepancy. More importantly, this paper demonstrates that spectroscopic follow-up observations of microlensing events are possible and provide independent constraints on the parameters of the lens and source stars, hence breaking some degeneracies in the analysis. UV-to-NIR low-resolution spectrographs like X-shooter (ESOVLT) could substantially contribute to this follow-up efforts, with magnitude limits above all microlensing events detected so far.

  10. Foreign launch competition growing

    NASA Astrophysics Data System (ADS)

    Brodsky, R. F.; Wolfe, M. G.; Pryke, I. W.

    1986-07-01

    A survey is given of progress made by other nations in providing or preparing to provide satellite launch services. The European Space Agency has four generations of Ariane vehicles, with a fifth recently approved; a second launch facility in French Guiana that has become operational has raised the possible Ariane launch rate to 10 per year, although a May failure of an Ariane 2 put launches on hold. The French Hermes spaceplane and the British HOTOL are discussed. Under the auspices of the Italian National Space Plane, the Iris orbital transfer vehicle is developed and China's Long March vehicles and the Soviet Protons and SL-4 vehicles are discussed; the Soviets moreover are apparently developing not only a Saturn V-class heavy lift vehicle with a 150,000-kg capacity (about five times the largest U.S. capacity) but also a space shuttle and a spaceplane. Four Japanese launch vehicles and some vehicles in an Indian program are also ready to provide launch services. In this new, tough market for launch services, the customers barely outnumber the suppliers. The competition develops just as the Challenger and Titan disasters place the U.S. at a disadvantage and underline the hard work ahead to recoup its heretofore leading position in launch services.

  11. NARROW-LINE-WIDTH UV BURSTS IN THE TRANSITION REGION ABOVE SUNSPOTS OBSERVED BY IRIS

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

    Hou, Zhenyong; Huang, Zhenghua; Xia, Lidong

    Various small-scale structures abound in the solar atmosphere above active regions, playing an important role in the dynamics and evolution therein. We report on a new class of small-scale transition region structures in active regions, characterized by strong emissions but extremely narrow Si iv line profiles as found in observations taken with the Interface Region Imaging Spectrograph (IRIS). Tentatively named as narrow-line-width UV bursts (NUBs), these structures are located above sunspots and comprise one or multiple compact bright cores at sub-arcsecond scales. We found six NUBs in two data sets (a raster and a sit-and-stare data set). Among these, fourmore » events are short-lived with a duration of ∼10 minutes, while two last for more than 36 minutes. All NUBs have Doppler shifts of 15–18 km s{sup −1}, while the NUB found in sit-and-stare data possesses an additional component at ∼50 km s{sup −1} found only in the C ii and Mg ii lines. Given that these events are found to play a role in the local dynamics, it is important to further investigate the physical mechanisms that generate these phenomena and their role in the mass transport in sunspots.« less

  12. Observations of Electron-driven Evaporation in a Flare Precursor

    NASA Astrophysics Data System (ADS)

    Li, Dong; Li, Ying; Su, Wei; Huang, Yu; Ning, Zongjun

    2018-02-01

    We investigate the relationship between the blueshifts of a hot emission line and the nonthermal emissions in microwave and hard X-ray (HXR) wavelengths in the precursor of a solar flare on 2014 October 27. The flare precursor is identified as a small but well-developed peak in the soft X-ray and extreme-ultraviolet passbands before the GOES flare onset, which is accompanied by a pronounced burst in microwave 17 and 34 GHz and in HXR 25–50 keV. The slit of the Interface Region Imaging Spectrograph (IRIS) stays on one ribbon-like transient during the flare precursor phase, which shows visible nonthermal emissions in Nobeyama Radioheliograph and RHESSI images. The IRIS spectroscopic observations show that the hot line of Fe XXI 1354.09 Å (log T ∼ 7.05) displays blueshifts, while the cool line of Si IV 1402.77 Å (log T ∼ 4.8) exhibits redshifts. The blueshifts and redshifts are well correlated with each other, indicative of an explosive chromospheric evaporation during the flare precursor phase combining a high nonthermal energy flux with a short characteristic timescale. In addition, the blueshifts of Fe XXI 1354.09 Å are well correlated with the microwave and HXR emissions, implying that the explosive chromospheric evaporation during the flare precursor phase is driven by nonthermal electrons.

  13. A Si IV/O IV Electron Density Diagnostic for the Analysis of IRIS Solar Spectra

    NASA Astrophysics Data System (ADS)

    Young, P. R.; Keenan, F. P.; Milligan, R. O.; Peter, H.

    2018-04-01

    Solar spectra of ultraviolet bursts and flare ribbons from the Interface Region Imaging Spectrograph (IRIS) have suggested high electron densities of > {10}12 cm‑3 at transition region temperatures of 0.1 MK, based on large intensity ratios of Si IV λ1402.77 to O IV λ1401.16. In this work, a rare observation of the weak O IV λ1343.51 line is reported from an X-class flare that peaked at 21:41 UT on 2014 October 24. This line is used to develop a theoretical prediction of the Si IV λ1402.77 to O IV λ1401.16 ratio as a function of density that is recommended to be used in the high-density regime. The method makes use of new pressure-dependent ionization fractions that take account of the suppression of dielectronic recombination at high densities. It is applied to two sequences of flare kernel observations from the October 24 flare. The first shows densities that vary between 3× {10}12 and 3× {10}13 cm‑3 over a seven-minute period, while the second location shows stable density values of around 2× {10}12 cm‑3 over a three-minute period.

  14. Spectra Handling from AIRS and IRIS for Climate Change Research

    NASA Astrophysics Data System (ADS)

    Jiang, Y.; Lau, M.; Aumann, H. H.; Yung, Y. L.

    2010-12-01

    Outgoing longwave radiation (OLR) measurements over a long period from satellites provide valuable information for the climate change research. Due to the different coverage, spectral resolution and instrument sensitivities, the data comparisons between different satellites could be problematic and possible artifacts could be easily introduced. In this paper, we have analyzed the data taken by IRIS in 1970 and by AIRS from 2002 to 2010. IRIS (Prabhakara, 1988) was a Fourier transform spectrometer (FTS) and it flew on the NASA Nimbus 4 satellite which was launched in April 1970 into an 1100km altitude sun-synchronous polar orbit. It collected data from the nadir track between 400cm-1 and 1600 cm-1 from April 1970 until January 1971. AIRS (Aumann, 2003) is a grating spectrometer launched on the EOS-Aqua satellite in May 2002 and it measures spectra from 650cm-1 to 2700cm-1. AIRS scans to ±49.5o cross track as the satellite moves forwards taking 90 spectra each with an instantaneous field of view of 1.1o in a row perpendicular to the direction of motion of the satellite. This results in a ground footprint of 13km diameter at nadir. In this paper, we analyzed the spectra between 650 cm-1 and 1350 cm-1 for nadir view footprints in order to match the IRIS’s measurements. Most of the possible sources of error or biases have been carefully handled, these include the errors from the data editing, spatial coverage, missing data (spatial gap), and spectral resolution, spectra frequency shift due to the fields of view, sea surface temperature fluctuations, clear sky determination, and spectra response function symmetry. It is extremely important when comparing spectra in the high slope spectra regions where possible large artifacts could be introduced. We have used a radiative model to simulate the spectra as observed in both IRIS and AIRS by using US Standard Atmospheric Profiles. The tropospheric warming and stratospheric warming are introduced in the model as well. The model shows consistent spectra for both clear sky and low cloud with both AIRS and IRIS by introducing water vapor in the model. The model results indicate the CO2 and CH4 increase which is consistent with the IPCC report. Due to the broad emission range of the water vapor in the troposphere, it plays a significant role in the model simulations.

  15. TESIS experiment on XUV imaging spectroscopy of the Sun onboard the CORONAS-PHOTON satellite

    NASA Astrophysics Data System (ADS)

    Kuzin, S. V.; Zhitnik, I. A.; Bogachev, S. A.; Shestov, S. V.; Bugaenko, O. I.; Suhodrev, N. K.; Pertsov, A. A.; Mitrofanov, A. V.; Ignat'ev, A. P.; Slemzin, V. A.

    We present a brief description of new complex of space telescopes and spectrographs, TESIS, which will be placed aboard the CORONAS-PHOTON satellite. The complex is intended for high-resolution imaging observation of full Sun in the coronal spectral lines and in the spectral lines of the solar transition region. TESIS will be launched at the end of 2007 - early of 2008. About 25 % of the daily TESIS images will be free for use and for downloading from the TESIS data center that is planned to open 2 months before the TESIS launching at http://www.tesis.lebedev.ru

  16. Cool and hot emission in a recurring active region jet

    NASA Astrophysics Data System (ADS)

    Mulay, Sargam M.; Zanna, Giulio Del; Mason, Helen

    2017-09-01

    Aims: We present a thorough investigation of the cool and hot temperature components in four recurring active region jets observed on July 10, 2015 using the Atmospheric Imaging Assembly (AIA), X-ray Telescope (XRT), and Interface Region Imaging Spectrograph (IRIS) instruments. Methods: A differential emission measure (DEM) analysis was performed on areas in the jet spire and footpoint regions by combining the IRIS spectra and the AIA observations. This procedure better constrains the low temperature DEM values by adding IRIS spectral lines. Plasma parameters, such as Doppler velocities, electron densities, nonthermal velocities and a filling factor were also derived from the IRIS spectra. Results: In the DEM analysis, significant cool emission was found in the spire and the footpoint regions. The hot emission was peaked at log T [K] = 5.6-5.9 and 6.5 respectively. The DEM curves show the presence of hot plasma (T = 3 MK) in the footpoint region. We confirmed this result by estimating the Fe XVIII emission from the AIA 94 Å channel which was formed at an effective temperature of log T [K] = 6.5. The average XRT temperatures were also found to be in agreement with log T [K] = 6.5. The emission measure (EM) was found to be three orders of magnitude higher in the AIA-IRIS DEM compared with that obtained using only AIA. The O IV (1399/1401 Å) electron densities were found to be 2.0×1010 cm-3 in the spire and 7.6 × 1010 cm-3 in the footpoint. Different threads along the spire show different plane-of-sky velocities both in the lower corona and transition region. Doppler velocities of 32 km s-1 (blueshifted) and 13 km s-1 (redshifted) were obtained in the spire and footpoint, respectively from the Si IV 1402.77 Å spectral line. Nonthermal velocities of 69 and 53 km s-1 were recorded in the spire and footpoint region, respectively. We obtained a filling factor of 0.1 in the spire at log T [K] = 5. Conclusions: The recurrent jet observations confirmed the presence of significant cool emission co-spatial with the coronal emission. The movie attached to Fig. 3 is available at http://www.aanda.org

  17. Chromospheric impact of an exploding solar granule

    NASA Astrophysics Data System (ADS)

    Fischer, C. E.; Bello González, N.; Rezaei, R.

    2017-06-01

    Context. Observations of multi-wavelength and therefore height-dependent information following events throughout the solar atmosphere and unambiguously assigning a relation between these rapidly evolving layers are rare and difficult to obtain. Yet, they are crucial for our understanding of the physical processes that couple the different regimes in the solar atmosphere. Aims: We characterize the exploding granule event with simultaneous observations of Hinode spectroplarimetric data in the solar photosphere and Hinode broadband Ca II H images combined with Interface Region Imaging Spectrograph (IRIS) slit spectra. We follow the evolution of an exploding granule and its connectivity throughout the atmosphere and analyze the dynamics of a magnetic element that has been affected by the abnormal granule. Methods: In addition to magnetic flux maps we use a local correlation tracking method to infer the horizontal velocity flows in the photosphere and apply a wavelet analysis on several IRIS chromospheric emission features such as Mg II k2v and Mg II k3 to detect oscillatory phenomena indicating wave propagation. Results: During the vigorous expansion of the abnormal granule we detect radially outward horizontal flows, causing, together with the horizontal flows from the surrounding granules, the magnetic elements in the bordering intergranular lanes to be squeezed and elongated. In reaction to the squeezing, we detect a chromospheric intensity and velocity oscillation pulse which we identify as an upward traveling hot shock front propagating clearly through the IRIS spectral line diagnostics of Mg II h&k. Conclusions: Exploding granules can trigger upward-propagating shock fronts that dissipate in the chromosphere. Movies associated to Figs. A.1 and A.2 are available in electronic form at http://www.aanda.org

  18. Study on Precursor Activity of the X1.6 Flare in the Great AR 12192 with SDO , IRIS , and Hinode

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

    Bamba, Yumi; Lee, Kyoung-Sun; Imada, Shinsuke

    The physical properties and their contribution to the onset of a solar flare are still uncleare even though chromospheric brightening is considered a precursor phenomenon of a flare. Many studies suggested that photospheric magnetic field changes cause destabilization of large-scale coronal structure. We aim to understand how a small photospheric change contributes to a flare and to reveal how the intermediary chromosphere behaves in the precursor phase. We analyzed the precursor brightening of the X1.6 flare on 2014 October 22 in the AR 12192 using the Interface Region Imaging Spectrograph ( IRIS ) and Hinode /EUV Imaging Spectrometer (EIS) data.more » We investigated a localized jet with the strong precursor brightening, and compared the intensity, Doppler velocity, and line width in C ii, Mg ii k, and Si iv lines by IRIS and He ii, Fe xii, and Fe xv lines by Hinode /EIS. We also analyzed the photospheric magnetic field and chromospheric/coronal structures using the Solar Dynamics Observatory ( SDO )/Helioseismic and Magnetic Imager and Atmospheric Imaging Assembly. We found a significant blueshift (∼100 km s{sup −1}), which is related to the strong precursor brightening over a characteristic magnetic field structure, and the blueshift was observed at all of the temperatures. This might indicate that the flow is accelerated by Lorentz force. Moreover, the large-scale coronal loop that connects the foot points of the flare ribbons was destabilized just after the precursor brightening with the blueshift. It suggests that magnetic reconnection locally occurred in the lower chromosphere and it triggered magnetic reconnection of the X1.6 flare in the corona.« less

  19. THE FORMATION OF IRIS DIAGNOSTICS. VII. THE FORMATION OF THE O i 135.56 NM LINE IN THE SOLAR ATMOSPHERE

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

    Lin, Hsiao-Hsuan; Carlsson, Mats, E-mail: h.h.lin@astro.uio.no, E-mail: mats.carlsson@astro.uio.no

    The O i 135.56 nm line is covered by NASA's Interface Region Imaging Spectrograph (IRIS) small explorer mission which studies how the solar atmosphere is energized. We study here the formation and diagnostic potential of this line by means of non-local thermodynamic equilibrium modeling employing both 1D semi-empirical and 3D radiation magnetohydrodynamic models. We study the basic formation mechanisms and derive a quintessential model atom that incorporates essential atomic physics for the formation of the O i 135.56 nm line. This atomic model has 16 levels and describes recombination cascades through highly excited levels by effective recombination rates. The ionizationmore » balance O i/O ii is set by the hydrogen ionization balance through charge exchange reactions. The emission in the O i 135.56 nm line is dominated by a recombination cascade and the line is optically thin. The Doppler shift of the maximum emission correlates strongly with the vertical velocity in its line forming region, which is typically located at 1.0–1.5 Mm height. The total intensity of the line emission is correlated with the square of the electron density. Since the O i 135.56 nm line is optically thin, the width of the emission line is a very good diagnostic of non-thermal velocities. We conclude that the O i 135.56 nm line is an excellent probe of the middle chromosphere, and compliments other powerful chromospheric diagnostics of IRIS such as the Mg ii h and k lines and the C ii lines around 133.5 nm.« less

  20. ON THE ACTIVE REGION BRIGHT GRAINS OBSERVED IN THE TRANSITION REGION IMAGING CHANNELS OF IRIS

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

    Skogsrud, H.; Voort, L. Rouppe van der; Pontieu, B. De

    The Interface Region Imaging Spectrograph (IRIS) provides spectroscopy and narrow band slit-jaw (SJI) imaging of the solar chromosphere and transition region at unprecedented spatial and temporal resolutions. Combined with high-resolution context spectral imaging of the photosphere and chromosphere as provided by the Swedish 1 m Solar Telescope (SST), we can now effectively trace dynamic phenomena through large parts of the solar atmosphere in both space and time. IRIS SJI 1400 images from active regions, which primarily sample the transition region with the Si iv 1394 and 1403 Å lines, reveal ubiquitous bright “grains” which are short-lived (two to five minute)more » bright roundish small patches of sizes 0.″5–1.″7 that generally move limbward with velocities up to about 30 km s{sup −1}. In this paper, we show that many bright grains are the result of chromospheric shocks impacting the transition region. These shocks are associated with dynamic fibrils (DFs), most commonly observed in Hα. We find that the grains show the strongest emission in the ascending phase of the DF, that the emission is strongest toward the top of the DF, and that the grains correspond to a blueshift and broadening of the Si iv lines. We note that the SJI 1400 grains can also be observed in the SJI 1330 channel which is dominated by C ii lines. Our observations show that a significant part of the active region transition region dynamics is driven from the chromosphere below rather than from coronal activity above. We conclude that the shocks that drive DFs also play an important role in the heating of the upper chromosphere and lower transition region.« less

  1. Study on Precursor Activity of the X1.6 Flare in the Great AR 12192 with SDO, IRIS, and Hinode

    NASA Astrophysics Data System (ADS)

    Bamba, Yumi; Lee, Kyoung-Sun; Imada, Shinsuke; Kusano, Kanya

    2017-05-01

    The physical properties and their contribution to the onset of a solar flare are still uncleare even though chromospheric brightening is considered a precursor phenomenon of a flare. Many studies suggested that photospheric magnetic field changes cause destabilization of large-scale coronal structure. We aim to understand how a small photospheric change contributes to a flare and to reveal how the intermediary chromosphere behaves in the precursor phase. We analyzed the precursor brightening of the X1.6 flare on 2014 October 22 in the AR 12192 using the Interface Region Imaging Spectrograph (IRIS) and Hinode/EUV Imaging Spectrometer (EIS) data. We investigated a localized jet with the strong precursor brightening, and compared the intensity, Doppler velocity, and line width in C II, Mg II k, and Si IV lines by IRIS and He II, Fe xii, and Fe xv lines by Hinode/EIS. We also analyzed the photospheric magnetic field and chromospheric/coronal structures using the Solar Dynamics Observatory (SDO)/Helioseismic and Magnetic Imager and Atmospheric Imaging Assembly. We found a significant blueshift (˜100 km s-1), which is related to the strong precursor brightening over a characteristic magnetic field structure, and the blueshift was observed at all of the temperatures. This might indicate that the flow is accelerated by Lorentz force. Moreover, the large-scale coronal loop that connects the foot points of the flare ribbons was destabilized just after the precursor brightening with the blueshift. It suggests that magnetic reconnection locally occurred in the lower chromosphere and it triggered magnetic reconnection of the X1.6 flare in the corona.

  2. Investigating the Response of Loop Plasma to Nanoflare Heating Using RADYN Simulations

    NASA Astrophysics Data System (ADS)

    Polito, V.; Testa, P.; Allred, J.; De Pontieu, B.; Carlsson, M.; Pereira, T. M. D.; Gošić, Milan; Reale, Fabio

    2018-04-01

    We present the results of 1D hydrodynamic simulations of coronal loops that are subject to nanoflares, caused by either in situ thermal heating or nonthermal electron (NTE) beams. The synthesized intensity and Doppler shifts can be directly compared with Interface Region Imaging Spectrograph (IRIS) and Atmospheric Imaging Assembly (AIA) observations of rapid variability in the transition region (TR) of coronal loops, associated with transient coronal heating. We find that NTEs with high enough low-energy cutoff ({E}{{C}}) deposit energy in the lower TR and chromosphere, causing blueshifts (up to ∼20 km s‑1) in the IRIS Si IV lines, which thermal conduction cannot reproduce. The {E}{{C}} threshold value for the blueshifts depends on the total energy of the events (≈5 keV for 1024 erg, up to 15 keV for 1025 erg). The observed footpoint emission intensity and flows, combined with the simulations, can provide constraints on both the energy of the heating event and {E}{{C}}. The response of the loop plasma to nanoflares depends crucially on the electron density: significant Si IV intensity enhancements and flows are observed only for initially low-density loops (<109 cm‑3). This provides a possible explanation of the relative scarcity of observations of significant moss variability. While the TR response to single heating episodes can be clearly observed, the predicted coronal emission (AIA 94 Å) for single strands is below current detectability and can only be observed when several strands are heated closely in time. Finally, we show that the analysis of the IRIS Mg II chromospheric lines can help further constrain the properties of the heating mechanisms.

  3. Installation of an artificial vegetating island in oligomesotrophic Lake Paro, Korea.

    PubMed

    Seo, Eun-Young; Kwon, Oh-Byung; Choi, Seung-Ik; Kim, Ji-Ho; Ahn, Tae-Seok

    2013-01-01

    After cut off of inflowing water, Lake Paro, an oligomesotrophic lake lost littoral zone, an important region for the aquatic ecosystem. For the first step of restoration, the artificial vegetation island was installed. The concentration of nutrients in lake water was not sufficient for the growth of macrophyte as total phosphate was ranged from 58 to 83 μg L(-1). In order to overcome this problem, the hydrophobic substratum for bacterial attachment was selected as buoyant mat material of the artificial vegetation island. In this medium, total phosphate and total nitrogen were ranged from 190 to 1,060 μg L(-1) and from 4.9 to 9.1 mg L(-1), respectively. These concentrations were high enough for macrophytes growth. After launching 1,800 m(2) of AVI in Lake Paro, the macrophytes, Iris pseudoacorus and Iris ensata, grew well after five years of launching without the addition of fertilizer. Furthermore, fishes were plentiful under the artificial vegetation island, and ducks were observed on the artificial vegetation island. Bacteria using sunlight as energy source and self-designed ecotechnology can be used as an alternative method for the restoration of disturbed littoral zone in oligo-mesotrophic lakes.

  4. Installation of an Artificial Vegetating Island in Oligomesotrophic Lake Paro, Korea

    PubMed Central

    Seo, Eun-Young; Kwon, Oh-Byung; Choi, Seung-Ik; Kim, Ji-Ho; Ahn, Tae-Seok

    2013-01-01

    After cut off of inflowing water, Lake Paro, an oligomesotrophic lake lost littoral zone, an important region for the aquatic ecosystem. For the first step of restoration, the artificial vegetation island was installed. The concentration of nutrients in lake water was not sufficient for the growth of macrophyte as total phosphate was ranged from 58 to 83 μg L−1. In order to overcome this problem, the hydrophobic substratum for bacterial attachment was selected as buoyant mat material of the artificial vegetation island. In this medium, total phosphate and total nitrogen were ranged from 190 to 1,060 μg L−1 and from 4.9 to 9.1 mg L−1, respectively. These concentrations were high enough for macrophytes growth. After launching 1,800 m2 of AVI in Lake Paro, the macrophytes, Iris pseudoacorus and Iris ensata, grew well after five years of launching without the addition of fertilizer. Furthermore, fishes were plentiful under the artificial vegetation island, and ducks were observed on the artificial vegetation island. Bacteria using sunlight as energy source and self-designed ecotechnology can be used as an alternative method for the restoration of disturbed littoral zone in oligo-mesotrophic lakes. PMID:23935437

  5. Far-ultraviolet Spectroscopy of Recent Comets with the Cosmic Origins Spectrograph on the Hubble Space Telescope

    NASA Astrophysics Data System (ADS)

    Feldman, Paul D.; Weaver, Harold A.; A’Hearn, Michael F.; Combi, Michael R.; Dello Russo, Neil

    2018-05-01

    Since its launch in 1990, the Hubble Space Telescope (HST) has served as a platform with unique capabilities for remote observations of comets in the far-ultraviolet region of the spectrum. Successive generations of imagers and spectrographs have seen large advances in sensitivity and spectral resolution enabling observations of the diverse properties of a representative number of comets during the past 25 years. To date, four comets have been observed in the far-ultraviolet by the Cosmic Origins Spectrograph (COS), the last spectrograph to be installed in HST, in 2009: 103P/Hartley 2, C/2009 P1 (Garradd), C/2012 S1 (ISON), and C/2014 Q2 (Lovejoy). COS has unprecedented sensitivity, but limited spatial information in its 2.″5 diameter circular aperture, and our objective was to determine the CO production rates from measurements of the CO Fourth Positive system in the spectral range of 1400–1700 Å. In the two brightest comets, 19 bands of this system were clearly identified. The water production rates were derived from nearly concurrent observations of the OH (0,0) band at 3085 Å by the Space Telescope Imaging Spectrograph. The derived CO/{{{H}}}2{{O}} production rate ratio ranged from ∼0.3% for Hartley 2 to ∼22% for Garradd. In addition, strong partially resolved emission features due to multiplets of S I, centered at 1429 Å and 1479 Å, and of C I at 1561 Å and 1657 Å, were observed in all four comets. Weak emission from several lines of the {{{H}}}2 Lyman band system, excited by solar Lyα and Lyβ pumped fluorescence, were detected in comet Lovejoy.

  6. KSC-08pd2191

    NASA Image and Video Library

    2008-07-29

    CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center, workers from NASA's Goddard Space Flight Center roll the Cosmic Origins Spectrograph, or COS, into position in the clean room of the Payload Hazardous Servicing Facility for instrument testing and integration with the Flight Support System carrier. The COS will be installed on the Hubble Space Telescope on space shuttle Atlantis' STS-125 mission. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. COS's far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of STS-125 is targeted for Oct. 8. Photo credit: NASA/Jack Pfaller

  7. KSC-08pd2186

    NASA Image and Video Library

    2008-07-29

    CAPE CANAVERAL, Fla. – In the airlock of the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, workers from NASA's Goddard Space Flight Center lift the Cosmic Origins Spectrograph, or COS, from its transportation canister onto a dolly for its move into the clean room. The COS will be installed on the Hubble Space Telescope on space shuttle Atlantis' STS-125 mission. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. COS's far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of STS-125 is targeted for Oct. 8. Photo credit: NASA/Jack Pfaller

  8. KSC-08pd2188

    NASA Image and Video Library

    2008-07-29

    CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center, workers from NASA's Goddard Space Flight Center roll the Cosmic Origins Spectrograph, or COS, from the airlock, where it was removed from the shipping container, to the clean room of the Payload Hazardous Servicing Facility. The COS will be installed on the Hubble Space Telescope on space shuttle Atlantis' STS-125 mission. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. COS's far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of STS-125 is targeted for Oct. 8. Photo credit: NASA/Jack Pfaller

  9. KSC-08pd2187

    NASA Image and Video Library

    2008-07-29

    CAPE CANAVERAL, Fla. – In the airlock of the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center, workers from NASA's Goddard Space Flight Center lower the Cosmic Origins Spectrograph, or COS, onto a dolly for its move into the clean room. The COS will be installed on the Hubble Space Telescope on space shuttle Atlantis' STS-125 mission. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. COS's far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of STS-125 is targeted for Oct. 8. Photo credit: NASA/Jack Pfaller

  10. KSC-08pd2192

    NASA Image and Video Library

    2008-07-29

    CAPE CANAVERAL, Fla. – At NASA's Kennedy Space Center, workers from NASA's Goddard Space Flight Center prepare the Cosmic Origins Spectrograph, or COS, for instrument testing and integration with the Flight Support System carrier in the clean room of the Payload Hazardous Servicing Facility. The COS will be installed on the Hubble Space Telescope on space shuttle Atlantis' STS-125 mission. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. COS's far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of STS-125 is targeted for Oct. 8. Photo credit: NASA/Jack Pfaller

  11. KSC-2009-3103

    NASA Image and Video Library

    2009-05-11

    CAPE CANAVERAL, Fla. – The mini-convoy is lined up on the Shuttle Landing Facility runway at NASA's Kennedy Space Center in Florida awaiting space shuttle Atlantis' launch on the STS-125 mission to service NASA's Hubble Space Telescope. The convoy is prepared to act should the shuttle need to return to the launch site in the event of an emergency. At left is the Convoy Command Vehicle which is the command post for the convoy commander. Atlantis launched successfully on time at 2:01 p.m. EDT. Atlantis' 11-day flight will include five spacewalks to refurbish and upgrade the telescope with state-of-the-art science instruments that will expand Hubble's capabilities and extend its operational lifespan through at least 2014. The payload includes a Wide Field Camera 3, Fine Guidance Sensor and the Cosmic Origins Spectrograph. Photo credit: NASA/Jack Pfaller

  12. 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.

  13. Height formation of bright points observed by IRIS in Mg II line wings during flux emergence

    NASA Astrophysics Data System (ADS)

    Grubecka, M.; Schmieder, B.; Berlicki, A.; Heinzel, P.; Dalmasse, K.; Mein, P.

    2016-09-01

    Context. A flux emergence in the active region AR 111850 was observed on September 24, 2013 with the Interface Region Imaging Spectrograph (IRIS). Many bright points are associated with the new emerging flux and show enhancement brightening in the UV spectra. Aims: The aim of this work is to compute the altitude formation of the compact bright points (CBs) observed in Mg II lines in the context of searching Ellerman bombs (EBs). Methods: IRIS provided two large dense rasters of spectra in Mg II h and k lines, Mg II triplet, C II and Si IV lines covering all the active region and slit jaws in the two bandpasses (1400 Å and 2796 Å) starting at 11:44 UT and 15:39 UT, and lasting 20 min each. Synthetic profiles of Mg II and Hα lines are computed with non-local thermodynamic equlibrium (NLTE) radiative transfer treatment in 1D solar atmosphere model including a hotspot region defined by three parameters: temperature, altitude, and width. Results: Within the two IRIS rasters, 74 CBs are detected in the far wings of the Mg II lines (at +/-1 Å and 3.5 Å). Around 10% of CBs have a signature in Si IV and CII. NLTE models with a hotspot located in the low atmosphere were found to fit a sample of Mg II profiles in CBs. The Hα profiles computed with these Mg II CB models are consistent with typical EB profiles observed from ground based telescopes e.g. THEMIS. A 2D NLTE modelling of fibrils (canopy) demonstrates that the Mg II line centres can be significantly affected but not the peaks and the wings of Mg II lines. Conclusions: We conclude that the bright points observed in Mg II lines can be formed in an extended domain of altitudes in the photosphere and/or the chromosphere (400 to 750 km). Our results are consistent with the theory of heating by Joule dissipation in the atmosphere produced by magnetic field reconnection during flux emergence.

  14. Adaptive optics at the Subaru telescope: current capabilities and development

    NASA Astrophysics Data System (ADS)

    Guyon, Olivier; Hayano, Yutaka; Tamura, Motohide; Kudo, Tomoyuki; Oya, Shin; Minowa, Yosuke; Lai, Olivier; Jovanovic, Nemanja; Takato, Naruhisa; Kasdin, Jeremy; Groff, Tyler; Hayashi, Masahiko; Arimoto, Nobuo; Takami, Hideki; Bradley, Colin; Sugai, Hajime; Perrin, Guy; Tuthill, Peter; Mazin, Ben

    2014-08-01

    Current AO observations rely heavily on the AO188 instrument, a 188-elements system that can operate in natural or laser guide star (LGS) mode, and delivers diffraction-limited images in near-IR. In its LGS mode, laser light is transported from the solid state laser to the launch telescope by a single mode fiber. AO188 can feed several instruments: the infrared camera and spectrograph (IRCS), a high contrast imaging instrument (HiCIAO) or an optical integral field spectrograph (Kyoto-3DII). Adaptive optics development in support of exoplanet observations has been and continues to be very active. The Subaru Coronagraphic Extreme-AO (SCExAO) system, which combines extreme-AO correction with advanced coronagraphy, is in the commissioning phase, and will greatly increase Subaru Telescope's ability to image and study exoplanets. SCExAO currently feeds light to HiCIAO, and will soon be combined with the CHARIS integral field spectrograph and the fast frame MKIDs exoplanet camera, which have both been specifically designed for high contrast imaging. SCExAO also feeds two visible-light single pupil interferometers: VAMPIRES and FIRST. In parallel to these direct imaging activities, a near-IR high precision spectrograph (IRD) is under development for observing exoplanets with the radial velocity technique. Wide-field adaptive optics techniques are also being pursued. The RAVEN multi-object adaptive optics instrument was installed on Subaru telescope in early 2014. Subaru Telescope is also planning wide field imaging with ground-layer AO with the ULTIMATE-Subaru project.

  15. OBSERVATION AND ANALYSIS OF BALLISTIC DOWNFLOWS IN AN M-CLASS FLARE WITH THE INTERFACE REGION IMAGING SPECTROGRAPH

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

    Brannon, Sean R.

    Despite significant advances in instrumentation, there remain no studies that analyze observations of on-disk flare loop plasma flows covering the entire evolution from chromospheric evaporation, through plasma cooling, to draining downflows. We present results from an imaging and spectroscopic observation from the Interface Region Imaging Spectrograph ( IRIS ) of the SOL2015–03–12T11:50:00 M-class flare, at high spatial resolution and time cadence. Our analysis of this event reveals initial plasma evaporation at flare temperatures indicated by 100–200 km s{sup −1} blueshifts in the Fe xxi line. We subsequently observe plasma cooling into chromospheric lines (Si iv and O iv) with ∼11more » minute delay, followed by loop draining at ∼40 km s{sup −1} as indicated by a “C”-shaped redshift structure and significant (∼60 km s{sup −1}) non-thermal broadening. We use density-sensitive lines to calculate a plasma density for the flare loops, and estimate a theoretical cooling time approximately equal to the observed delay. Finally, we use a simple elliptical free-fall draining model to construct synthetic spectra, and perform what we believe to be the first direct comparison of such synthetic spectra to observations of draining downflows in flare loops.« less

  16. Searching for Spectroscopic Signs of Termination Shocks in Solar Flares

    NASA Astrophysics Data System (ADS)

    Galan, G.; Polito, V.; Reeves, K.

    2017-12-01

    The standard flare model predicts the presence of a termination shock located above the flare loop tops, however terminations shocks have not yet been well observed. We analyze flare observations by the Interface Region Imaging Spectrograph (IRIS), which provides cotemporal UV imaging and spectral data. Specifically, we study plasma emissions in the Fe XXI line, formed at the very hot plasma temperatures in flares (> 10 MK). Imaging observations that point to shocks include fast hot reconnection downflows above the loop tops and localized dense, bright plasma at the loop tops; spectral signatures that suggest shocks in the locality of the loop tops include redshifts and nonthermal broadening of the Fe XXI line. We identify possibly significant redshifts in some on-disk flare events observed by IRIS. Redshifts are observed in the vicinity of the bright loop top source that is thought to coincide with the site of the shock. In these events, the Fe XXI emissions at the time of the redshifted structures are dominated by at the at-rest components. The much more less intense redshifted components are broader, with velocities of 200 km/s. The spatial location of these shifts might indicate plasma motions and speeds indicative of termination shocks. This work is supported by the NSF-REU solar physics program at SAO, grant number AGS-1560313, and by NASA Grant NNX15AJ93G. Keywords: Solar flares, Solar magnetic reconnection, Termination shocks

  17. A New Method to Comprehensively Diagnose Shock Waves in the Solar Atmosphere Based on Simultaneous Spectroscopic and Imaging Observations

    NASA Astrophysics Data System (ADS)

    Ruan, Wenzhi; Yan, Limei; He, Jiansen; Zhang, Lei; Wang, Linghua; Wei, Yong

    2018-06-01

    Shock waves are believed to play an important role in plasma heating. The shock-like temporal jumps in radiation intensity and Doppler shift have been identified in the solar atmosphere. However, a quantitative diagnosis of the shocks in the solar atmosphere is still lacking, seriously hindering the understanding of shock dissipative heating of the solar atmosphere. Here, we propose a new method to realize the goal of the shock quantitative diagnosis, based on Rankine–Hugoniot equations and taking the advantages of simultaneous imaging and spectroscopic observations from, e.g., IRIS (Interface Region Imaging Spectrograph). Because of this method, the key parameters of shock candidates can be derived, such as the bulk velocity and temperature of the plasma in the upstream and downstream, the propagation speed and direction. The method is applied to the shock candidates observed by IRIS, and the overall characteristics of the shocks are revealed quantitatively for the first time. This method is also tested with the help of forward modeling, i.e., virtual observations of simulated shocks. The parameters obtained from the method are consistent with the parameters of the shock formed in the model and are independent of the viewing direction. Therefore, the method we proposed here is applicable to the quantitative and comprehensive diagnosis of the observed shocks in the solar atmosphere.

  18. EO-1/Hyperion: Nearing Twelve Years of Successful Mission Science Operation and Future Plans

    NASA Technical Reports Server (NTRS)

    Middleton, Elizabeth M.; Campbell, Petya K.; Huemmrich, K. Fred; Zhang, Qingyuan; Landis, David R.; Ungar, Stephen G.; Ong, Lawrence; Pollack, Nathan H.; Cheng, Yen-Ben

    2012-01-01

    The Earth Observing One (EO-1) satellite is a technology demonstration mission that was launched in November 2000, and by July 2012 will have successfully completed almost 12 years of high spatial resolution (30 m) imaging operations from a low Earth orbit. EO-1 has two unique instruments, the Hyperion and the Advanced Land Imager (ALI). Both instruments have served as prototypes for NASA's newer satellite missions, including the forthcoming (in early 2013) Landsat-8 and the future Hyperspectral Infrared Imager (HyspIRI). As well, EO-1 is a heritage platform for the upcoming German satellite, EnMAP (2015). Here, we provide an overview of the mission, and highlight the capabilities of the Hyperion for support of science investigations, and present prototype products developed with Hyperion imagery for the HyspIRI and other space-borne spectrometers.

  19. Application synergies between the NASA Pre- Aerosol Cloud and ocean Ecosystem (PACE) and Hyperspectral Infrared Imager (HyspIRI) missions

    NASA Astrophysics Data System (ADS)

    Lee, C. M.; Omar, A. H.; Hook, S. J.; Tzortziou, M.; Luvall, J. C.; Turner, W. W.

    2016-02-01

    Observations from the Pre-Aerosol Cloud and ocean Ecosystem (PACE) and Hyperspectral InfraRed Imager (HyspIRI) satellite missions are highly complementary and have the potential to significantly advance understanding of various science and applications challenges in the ocean sciences and water quality communities. Scheduled for launch in the 2022 timeframe, PACE is designed to make climate-quality global measurements essential for understanding ocean biology, biogeochemistry and ecology, and determining the role of the ocean in global biogeochemical cycling and ocean ecology, and how it affects and is affected by climate change. PACE will provide high signal-to-noise, hyperspectral observations over an extended spectral range (UV to SWIR) and will have global coverage every 1-2 days, at approximately 1 km spatial resolution; furthermore, PACE is currently designed to include a polarimeter, which will vastly improve atmospheric correction algorithms over water bodies. The PACE mission will enable advances in applications across a range of areas, including oceans, climate, water resources, ecological forecasting, disasters, human health and air quality. HyspIRI, with contiguous measurements in VSWIR, and multispectral measurements in TIR, will be able to provide detailed spectral observations and higher spatial resolution (30 to 60-m) over aquatic systems, but at a temporal resolution that is approximately 5-16 days. HyspIRI would enable improved, detailed studies of aquatic ecosystems, including benthic communities, algal blooms, coral reefs, and wetland species distribution as well as studies of water quality indicators or pollutants such as oil spills, suspended sediment, and colored dissolved organic matter. Together, PACE and HyspIRI will be able to address numerous applications and science priorities, including improving and extending climate data records, and studies of inland, coastal and ocean environments.

  20. The Farid & Moussa Raphael Observatory

    NASA Astrophysics Data System (ADS)

    Hajjar, R.

    2017-06-01

    The Farid & Moussa Raphael Observatory (FMRO) at Notre Dame University Louaize (NDU) is a teaching, research, and outreach facility located at the main campus of the university. It located very close to the Lebanese coast, in an urbanized area. It features a 60-cm Planewave CDK telescope, and instruments that allow for photometric and spetroscopic studies. The observatory currently has one thinned, back-illuminated CCD camera, used as the main imager along with Johnson-Cousin and Sloan photometric filters. It also features two spectrographs, one of which is a fiber fed echelle spectrograph. These are used with a dedicated CCD. The observatory has served for student projects, and summer schools for advanced undergraduate and graduate students. It is also made available for use by the regional and international community. The control system is currently being configured for remote observations. A number of long-term research projects are also being launched at the observatory.

  1. Extreme Ultraviolet Variability Experiment (EVE) Multiple EUV Grating Spectrographs (MEGS): Radiometric Calibrations and Results

    NASA Technical Reports Server (NTRS)

    Hock, R. A.; Woods, T. N.; Crotser, D.; Eparvier, F. G.; Woodraska, D. L.; Chamberlin, P. C.; Woods, E. C.

    2010-01-01

    The NASA Solar Dynamics Observatory (SDO), scheduled for launch in early 2010, incorporates a suite of instruments including the Extreme Ultraviolet Variability Experiment (EVE). EVE has multiple instruments including the Multiple Extreme ultraviolet Grating Spectrographs (MEGS) A, B, and P instruments, the Solar Aspect Monitor (SAM), and the Extreme ultraviolet SpectroPhotometer (ESP). The radiometric calibration of EVE, necessary to convert the instrument counts to physical units, was performed at the National Institute of Standards and Technology (NIST) Synchrotron Ultraviolet Radiation Facility (SURF III) located in Gaithersburg, Maryland. This paper presents the results and derived accuracy of this radiometric calibration for the MEGS A, B, P, and SAM instruments, while the calibration of the ESP instrument is addressed by Didkovsky et al. . In addition, solar measurements that were taken on 14 April 2008, during the NASA 36.240 sounding-rocket flight, are shown for the prototype EVE instruments.

  2. KSC-08pd2321

    NASA Image and Video Library

    2008-08-06

    CAPE CANAVERAL, Fla. –In the clean room of the Payload Hazardous Processing Facility at NASA's Kennedy Space Center, a worker from NASA's Goddard Space Flight Center uses black light inspection for a thorough cleaning of the Cosmic Origins Spectrograph, or COS. Black light inspection uses UVA fluorescence to detect possible particulate microcontamination, minute cracks or fluid leaks. The COS will be installed on the Hubble Space Telescope on space shuttle Atlantis' STS-125 mission. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. The COS far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of Atlantis on the STS-125 mission is targeted for Oct. 8. Photo credit: NASA/Kim Shiflett

  3. KSC-08pd2333

    NASA Image and Video Library

    2008-08-07

    CAPE CANAVERAL, Fla. – In the clean room of the Payload Hazardous Processing Facility at NASA's Kennedy Space Center, an overhead crane moves the Cosmic Origins Spectrograph, or COS, toward a protective enclosure on the Orbital Replacement Unit Carrier, part of the payload for the fifth and final Hubble servicing mission, STS-125. Other payloads include the Flight Support System, the Super Lightweight Interchangeable Carrier and the Multi-Use Lightweight Equipment, or MULE, carrier. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. The COS far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of Atlantis on the STS-125 mission is targeted for Oct. 8. Photo credit: NASA/Kim Shiflett

  4. KSC-08pd2336

    NASA Image and Video Library

    2008-08-07

    CAPE CANAVERAL, Fla. – In the clean room of the Payload Hazardous Processing Facility at NASA's Kennedy Space Center, an overhead crane lowers the Cosmic Origins Spectrograph, or COS, toward a protective enclosure on the Orbital Replacement Unit Carrier, part of the payload for the fifth and final Hubble servicing mission, STS-125. Other payloads include the Flight Support System, the Super Lightweight Interchangeable Carrier and the Multi-Use Lightweight Equipment, or MULE, carrier. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. The COS far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of Atlantis on the STS-125 mission is targeted for Oct. 8. Photo credit: NASA/Kim Shiflett

  5. KSC-08pd2325

    NASA Image and Video Library

    2008-08-06

    CAPE CANAVERAL, Fla. – In the clean room of the Payload Hazardous Processing Facility at NASA's Kennedy Space Center, a worker from NASA's Goddard Space Flight Center uses black light inspection for a thorough cleaning of the Cosmic Origins Spectrograph, or COS. Black light inspection uses UVA fluorescence to detect possible particulate microcontamination, minute cracks or fluid leaks. The COS will be installed on the Hubble Space Telescope on space shuttle Atlantis' STS-125 mission. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. The COS far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of Atlantis on the STS-125 mission is targeted for Oct. 8. Photo credit: NASA/Kim Shiflett

  6. KSC-08pd2332

    NASA Image and Video Library

    2008-08-07

    CAPE CANAVERAL, Fla. – In the clean room of the Payload Hazardous Processing Facility at NASA's Kennedy Space Center, an overhead crane moves the Cosmic Origins Spectrograph, or COS, toward a protective enclosure on the Orbital Replacement Unit Carrier, part of the payload for the fifth and final Hubble servicing mission, STS-125. Other payloads include the Flight Support System, the Super Lightweight Interchangeable Carrier and the Multi-Use Lightweight Equipment, or MULE, carrier. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. The COS far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of Atlantis on the STS-125 mission is targeted for Oct. 8. Photo credit: NASA/Kim Shiflett

  7. KSC-08pd2324

    NASA Image and Video Library

    2008-08-06

    CAPE CANAVERAL, Fla. – In the clean room of the Payload Hazardous Processing Facility at NASA's Kennedy Space Center, a worker from NASA's Goddard Space Flight Center uses black light inspection for a thorough cleaning of the Cosmic Origins Spectrograph, or COS. Black light inspection uses UVA fluorescence to detect possible particulate microcontamination, minute cracks or fluid leaks. The COS will be installed on the Hubble Space Telescope on space shuttle Atlantis' STS-125 mission. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. The COS far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of Atlantis on the STS-125 mission is targeted for Oct. 8. Photo credit: NASA/Kim Shiflett

  8. KSC-08pd2334

    NASA Image and Video Library

    2008-08-07

    CAPE CANAVERAL, Fla. – In the clean room of the Payload Hazardous Processing Facility at NASA's Kennedy Space Center, an overhead crane lowers the Cosmic Origins Spectrograph, or COS, toward a protective enclosure on the Orbital Replacement Unit Carrier, part of the payload for the fifth and final Hubble servicing mission, STS-125. Other payloads include the Flight Support System, the Super Lightweight Interchangeable Carrier and the Multi-Use Lightweight Equipment, or MULE, carrier. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. The COS far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of Atlantis on the STS-125 mission is targeted for Oct. 8. Photo credit: NASA/Kim Shiflett

  9. KSC-08pd2320

    NASA Image and Video Library

    2008-08-06

    CAPE CANAVERAL, Fla. –The outside of the Cosmic Origins Spectrograph, or COS, is seen before black light inspection in the clean room of the Payload Hazardous Processing Facility at NASA's Kennedy Space Center. Black light inspection uses UVA fluorescence to detect possible particulate microcontamination, minute cracks or fluid leaks. The COS will be installed on the Hubble Space Telescope on space shuttle Atlantis' STS-125 mission. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. The COS far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of Atlantis on the STS-125 mission is targeted for Oct. 8. Photo credit: NASA/Kim Shiflett

  10. KSC-08pd2335

    NASA Image and Video Library

    2008-08-07

    CAPE CANAVERAL, Fla. – In the clean room of the Payload Hazardous Processing Facility at NASA's Kennedy Space Center, an overhead crane lowers the Cosmic Origins Spectrograph, or COS, toward a protective enclosure on the Orbital Replacement Unit Carrier, part of the payload for the fifth and final Hubble servicing mission, STS-125. Other payloads include the Flight Support System, the Super Lightweight Interchangeable Carrier and the Multi-Use Lightweight Equipment, or MULE, carrier. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. The COS far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of Atlantis on the STS-125 mission is targeted for Oct. 8. Photo credit: NASA/Kim Shiflett

  11. KSC-08pd2338

    NASA Image and Video Library

    2008-08-07

    CAPE CANAVERAL, Fla. – In the clean room of the Payload Hazardous Processing Facility at NASA's Kennedy Space Center, an overhead crane lowers the Cosmic Origins Spectrograph, or COS, into a protective enclosure on the Orbital Replacement Unit Carrier, part of the payload for the fifth and final Hubble servicing mission, STS-125. Other payloads include the Flight Support System, the Super Lightweight Interchangeable Carrier and the Multi-Use Lightweight Equipment, or MULE, carrier. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. The COS far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of Atlantis on the STS-125 mission is targeted for Oct. 8. Photo credit: NASA/Kim Shiflett

  12. KSC-08pd2322

    NASA Image and Video Library

    2008-08-06

    CAPE CANAVERAL, Fla. – In the clean room of the Payload Hazardous Processing Facility at NASA's Kennedy Space Center, a worker from NASA's Goddard Space Flight Center uses black light inspection for a thorough cleaning of the Cosmic Origins Spectrograph, or COS. Black light inspection uses UVA fluorescence to detect possible particulate microcontamination, minute cracks or fluid leaks. The COS will be installed on the Hubble Space Telescope on space shuttle Atlantis' STS-125 mission. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. The COS far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of Atlantis on the STS-125 mission is targeted for Oct. 8. Photo credit: NASA/Kim Shiflett

  13. KSC-08pd2557

    NASA Image and Video Library

    2008-09-05

    CAPE CANAVERAL, Fla. – In the Payload Hazardous Servicing Facility at NASA’s Kennedy Space Center, crew members with the STS-125 mission get a close look at some of the equipment associated with their mission to service NASA’s Hubble Space Telescope. In the foreground, center, are Mission Specialists Mike Massimino and Michael Good, looking at the box containing the Cosmic Origins Spectrograph, or COS, on the orbital replacement unit carrier. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. The STS-125 crew is taking part in a crew equipment interface test, which provides experience handling tools, equipment and hardware they will use on their mission. Space shuttle Atlantis is targeted to launch on the STS-125 mission Oct. 10. Photo credit: NASA/Kim Shiflett

  14. KSC-08pd2337

    NASA Image and Video Library

    2008-08-07

    CAPE CANAVERAL, Fla. – In the clean room of the Payload Hazardous Processing Facility at NASA's Kennedy Space Center, an overhead crane lowers the Cosmic Origins Spectrograph, or COS, into a protective enclosure on the Orbital Replacement Unit Carrier, part of the payload for the fifth and final Hubble servicing mission, STS-125. Other payloads include the Flight Support System, the Super Lightweight Interchangeable Carrier and the Multi-Use Lightweight Equipment, or MULE, carrier. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. The COS far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of Atlantis on the STS-125 mission is targeted for Oct. 8. Photo credit: NASA/Kim Shiflett

  15. KSC-08pd2339

    NASA Image and Video Library

    2008-08-07

    CAPE CANAVERAL, Fla. – In the clean room of the Payload Hazardous Processing Facility at NASA's Kennedy Space Center, an overhead crane settles the Cosmic Origins Spectrograph, or COS, in a protective enclosure on the Orbital Replacement Unit Carrier, part of the payload for the fifth and final Hubble servicing mission, STS-125. Other payloads include the Flight Support System, the Super Lightweight Interchangeable Carrier and the Multi-Use Lightweight Equipment, or MULE, carrier. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. The COS far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of Atlantis on the STS-125 mission is targeted for Oct. 8. Photo credit: NASA/Kim Shiflett

  16. KSC-08pd2558

    NASA Image and Video Library

    2008-09-05

    CAPE CANAVERAL, Fla. – In the Payload Hazardous Servicing Facility at NASA’s Kennedy Space Center, crew members with the STS-125 mission get a close look at some of the equipment associated with their mission to service NASA’s Hubble Space Telescope. Looking at the box containing the Cosmic Origins Spectrograph, or COS, on the orbital replacement unit carrier are Mission Specialist Michael Good (upper right, on stand) and HST inspectors. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. The STS-125 crew is taking part in a crew equipment interface test, which provides experience handling tools, equipment and hardware they will use on their mission. Space shuttle Atlantis is targeted to launch on the STS-125 mission Oct. 10. Photo credit: NASA/Kim Shiflett

  17. KSC-08pd2323

    NASA Image and Video Library

    2008-08-06

    CAPE CANAVERAL, Fla. – In the clean room of the Payload Hazardous Processing Facility at NASA's Kennedy Space Center, a worker from NASA's Goddard Space Flight Center uses black light inspection for a thorough cleaning of the Cosmic Origins Spectrograph, or COS. Black light inspection uses UVA fluorescence to detect possible particulate microcontamination, minute cracks or fluid leaks. The COS will be installed on the Hubble Space Telescope on space shuttle Atlantis' STS-125 mission. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. The COS far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of Atlantis on the STS-125 mission is targeted for Oct. 8. Photo credit: NASA/Kim Shiflett

  18. The Goddard High Resolution Spectrograph Scientific Support Contract

    NASA Technical Reports Server (NTRS)

    1997-01-01

    In 1988, Computer Sciences Corporation (CSC) was selected as the Goddard High Resolution Spectrograph (GHRS) Scientific Support Contractor (SSC). This was to have been a few months before the launch of NASA's first Great Observatory, the Hubble Space Telescope (HST). As one of five scientific instruments on HST, the GHRS was designed to obtain spectra in the 1050-3300 A ultraviolet wavelength region with a resolving power, lambda/Delta(lambda) , of up to 100,000 and relative photometric accuracy to 1%. It was built by Ball AeroSpace Systems Group under the guidance of the GHRS Investigation Definition Team (IDT), comprised of 16 scientists from the US and Canada. After launch, the IDT was to perform the initial instrument calibration and execute a broad scientific program during a five-year Guaranteed Time Observation (GTO) period. After a year's delay, the launch of HST occurred in April 1990, and CSC participated in the in-orbit calibration and first four years of GTO observations with the IDT. The HST primary mirror suffered from spherical aberration, which reduced the spatial and spectral resolution of Large Science Aperture (LSA) observations and decreased the throughput of the Small Science Aperture (SSA) by a factor of two. Periodic problems with the Side 1 carrousel electronics and anomalies with the low-voltage power supply finally resulted in a suspension of the use of Side 1 less than two years after launch. At the outset, the GHRS SSC task involved work in four areas: 1) to manage and operate the GHRS Data Analysis Facility (DAF); 2) to support the second Servicing Mission Observatory Verification (SMOV) program, as well as perform system engineering analysis of the GHRS as nesessary; 3) to assist the GHRS IDT with their scientific research programs, particularly the GSFC members of the team, and 4) to provide administrative and logistic support for GHRS public information and educational activities.

  19. Bridging the Gap: Capturing the Lyα Counterpart of a Type-II Spicule and its Heating Evolution with VAULT2.0 and IRIS Campaign Observations

    NASA Astrophysics Data System (ADS)

    Chintzoglou, G.; De Pontieu, B.; Martinez-Sykora, J.; Mendes Domingos Pereira, T.; Vourlidas, A.; Tun Beltran, S.

    2017-12-01

    We present the analysis of data from the observing campaign in support to the VAULT2.0 sounding rocket launch on September 30, 2014. VAULT2.0 is a Lyα (1216 Å) spectroheliograph capable of providing fast cadence spectroheliograms of high-spectral purity. High resolution Lyα observations are highly complementary with the IRIS observations of the upper chromosphere and the low transition region but have previously been unavailable. The VAULT2.0 data provide critical, new upper-chromospheric constraints for numerical models. The observing campaign was closely coordinated with the IRIS mission. Taking advantage of this simultaneous multi-wavelength coverage of target AR 12172 and by using state-of-the-art radiative-MHD simulations of spicules, we are able to perform a detailed investigation of a type-II spicule associated with a fast apparent network jet recorded in the campaign observations during the VAULT2.0 flight. Our unique analysis suggests that spicular material exists suspended in lower temperatures until it rapidly gets heated and becomes visible in transition-region temperatures as an apparent network jet.

  20. FIREBALL-2: Pioneering Space UV Baryon Mapping (Lead Institution)

    NASA Astrophysics Data System (ADS)

    Schiminovich, David

    This is the lead proposal of a multi-institutional submission. The Faint Intergalactic-medium Redshifted Emission Balloon (FIREBall-2) is designed to discover and map faint emission from the Intergalactic Medium (IGM) for low redshift galaxies. This balloon is a modification of FIREBall-1 (FB-1), a path-finding mission built by our team with two successful flights. FB-1 provided the strongest constrains on IGM emission available from any instrument at the time. FIREBall-2 has been significantly upgraded compared to FB-1, and is nearly ready for integration and testing before an anticipated Spring 2016 launch from Ft. Sumner, New Mexico. The spectrograph has been redesigned and an upgraded detector system including a groundbreaking high QE, low-noise, UV CCD detector is under final testing and will improve instrument performance by more than an order of magnitude. CNES is providing the spectrograph, gondola, and flight support team, with construction of all components nearly complete. The initial FIREBall-2 launch is now scheduled for Spring 2016. FIREBall-2 combines several innovations: -First ever multi-object UV spectrograph -Arcsecond quality balloon pointing system, developed from scratch, improved from FB-1 -Partnership of national space agencies (NASA & CNES); highly leveraged NASA resources -A Schmidt corrector built into the UV grating for better optical performance and throughput -A total of four women trained in space experimental astrophysics, including 3 Columbia Ph.Ds. and 1 Caltech Ph.D. -A total of 7 graduate students trained on FIREBall-1 (3) and FIREBall-2 (4), with opportunities for more in future flights. FIREBall-2 will test key technologies and science strategies for a future mission to map IGM emission. Its flights will provide important training for the next generation of space astrophysicists working in UV instrumentation. Most importantly, FIREBall-2 will detect emission from the CGM of nearby galaxies, providing the first census of the density and kinematics of this material for low z galaxies and opening a new field of CGM science.

  1. An Analysis of Eruptions Detected by the LMSAL Eruption Patrol

    NASA Astrophysics Data System (ADS)

    Hurlburt, N. E.; Higgins, P. A.; Jaffey, S.

    2014-12-01

    Observations of the solar atmosphere reveals a wide range of real and apparent motions, from small scale jets and spicules to global-scale coronal mass ejections. Identifying and characterizing these motions are essential to advance our understanding the drivers of space weather. Automated and visual identifications are used in identifying CMEs. To date, the precursors to these — eruptions near the solar surface — have been identified primarily by visual inspection. Here we report on an analysis of the eruptions detected by the Eruption Patrol, a data mining module designed to automatically identify eruptions from data collected by Solar Dynamics Observatory's Atmospheric Imaging Assembly (SDO/AIA). We describe the module and use it both to explore relations with other solar events recorded in the Heliophysics Event Knowledgebase and to identify and access data collected by the Interface Region Imaging Spectrograph (IRIS) and Solar Optical Telescope (SOT) on Hinode for further analysis.

  2. Suppression of the near-infrared OH night-sky lines with fibre Bragg gratings - first results

    NASA Astrophysics Data System (ADS)

    Ellis, S. C.; Bland-Hawthorn, J.; Lawrence, J.; Horton, A. J.; Trinh, C.; Leon-Saval, S. G.; Shortridge, K.; Bryant, J.; Case, S.; Colless, M.; Couch, W.; Freeman, K.; Gers, L.; Glazebrook, K.; Haynes, R.; Lee, S.; Löhmannsröben, H.-G.; O'Byrne, J.; Miziarski, S.; Roth, M.; Schmidt, B.; Tinney, C. G.; Zheng, J.

    2012-09-01

    The background noise between 1 and 1.8 μm in ground-based instruments is dominated by atmospheric emission from hydroxyl molecules. We have built and commissioned a new instrument, the Gemini Near-infrared OH Suppression Integral Field Unit (IFU) System (GNOSIS), which suppresses 103 OH doublets between 1.47 and 1.7 μm by a factor of ≈1000 with a resolving power of ≈10 000. We present the first results from the commissioning of GNOSIS using the IRIS2 spectrograph at the Anglo-Australian Telescope. We present measurements of sensitivity, background and throughput. The combined throughput of the GNOSIS fore-optics, grating unit and relay optics is ≈36 per cent, but this could be improved to ≈46 per cent with a more optimal design. We measure strong suppression of the OH lines, confirming that OH suppression with fibre Bragg gratings will be a powerful technology for low-resolution spectroscopy. The integrated OH suppressed background between 1.5 and 1.7 μm is reduced by a factor of 9 compared to a control spectrum using the same system without suppression. The potential of low-resolution OH-suppressed spectroscopy is illustrated with example observations of Seyfert galaxies and a low-mass star. The GNOSIS background is dominated by detector dark current below 1.67 μm and by thermal emission above 1.67 μm. After subtracting these, we detect an unidentified residual interline component of ≈860 ± 210 photons s-1 m-2 arcsec-2 μm-1, comparable to previous measurements. This component is equally bright in the suppressed and control spectra. We have investigated the possible source of the interline component, but were unable to discriminate between a possible instrumental artefact and intrinsic atmospheric emission. Resolving the source of this emission is crucial for the design of fully optimized OH suppression spectrographs. The next-generation OH suppression spectrograph will be focused on resolving the source of the interline component, taking advantage of better optimization for a fibre Bragg grating feed incorporating refinements of design based on our findings from GNOSIS. We quantify the necessary improvements for an optimal OH suppressing fibre spectrograph design.

  3. Results of the IRIS UV Burst Survey, Part I: Active Regions Tracked Limb to Limb

    NASA Astrophysics Data System (ADS)

    Madsen, C. A.; DeLuca, E.

    2017-12-01

    We present results from the first phase of an effort to thoroughly characterize UV bursts within the Interface Region Imaging Spectrograph (IRIS) data catalogue. The observational signatures of these phenomena include dramatically intensified and broadened NUV/FUV emission line profiles with absorption features from cool metallic ions. These properties suggest that UV bursts originate from plasma at transition region temperatures (≥ 80,000 K) which is deeply embedded in the cool lower chromosphere ( 5,000 K). Rigorously characterizing the energetic and dynamical properties of UV bursts is crucial since they have considerable potential to heat active region chromospheres and could provide critical constraints for models of magnetic reconnection in these regions. The survey first focuses on IRIS observations of active regions tracked from limb to limb. All observations consist of large field-of-view raster scans of 320 or 400 steps each, which allow for widespread detection of many burst profiles at the expense of having limited short-term time evolution information. We detect bursts efficiently by applying a semi-automated single-Gaussian fitting technique to Si IV 1393.8 Å emission profiles that isolates the distinct burst population in a 4-D parameter space. The robust sample of NUV/FUV burst spectra allows for precise constraints of properties critical for modeling reconnection in the chromosphere, including outflow kinetic energy, density estimates from intensity ratios of Si IV 1402.8 Å and O IV 1401.2 Å emission lines, and coincident measures of emission in other wavelengths. We also track burst properties throughout the lifetimes of their host active regions, noting changes in detection rate and preferential location as the active regions evolve. Finally, the tracked active region observations provide a unique opportunity to investigate line-of-sight effects on observed UV burst spectral properties, particularly the strength of Ni II 1393.3 Å absorption, a feature that may be important in identifying the upward conduction of burst thermal energy through the chromosphere.

  4. A new Cassegrain calibration lamp unit for the Blanco Telescope

    NASA Astrophysics Data System (ADS)

    Points, S. D.; James, D. J.; Tighe, R.; Montané, A.; David, N.; Martínez, M.

    2016-08-01

    The f/8 RC-Cassegrain Focus of the Blanco Telescope at Cerro Tololo Inter-American Observatory, hosts two new instruments: COSMOS, a multi-object spectrograph in the visible wavelength range (350 - 1030nm), and ARCoIRIS, a NIR cross-dispersed spectrograph featuring 6 spectral orders spanning 0.8 - 2.45μm. Here we describe a calibration lamp unit designed to deliver the required illumination at the telescope focal plane for both instruments. These requirements are: (1) an f/8 beam of light covering a spot of 92mm diameter (or 10 arcmin) for a wavelength range of 0.35μm through 2.5μm and (2) no saturation of flat-field calibrations for the minimal exposure times permitted by each instrument, and (3) few saturated spectral lines when using the wavelength calibration lamps for the instruments. To meet these requirements this unit contains an adjustable quartz halogen lamp for flat-field calibrations, and one hollow cathode lamp and four penray lamps for wavelength calibrations. The wavelength calibration lamps are selected to provide optimal spectral coverage for the instrument mounted and can be used individually or in sets. The device designed is based on an 8-inch diameter integrating sphere, the output of which is optimized to match the f/8 calibration input delivery system which is a refractive system based on fused-silica lenses. We describe the optical design, the opto-mechanical design, the electronic control and give results of the performance of the system.

  5. Prospects for measuring supermassive black hole masses with future extremely large telescopes

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

    Do, Tuan; Wright, Shelley A.; Barth, Aaron J.

    2014-04-01

    The next generation of giant-segmented mirror telescopes (>20 m) will enable us to observe galactic nuclei at much higher angular resolution and sensitivity than ever before. These capabilities will introduce a revolutionary shift in our understanding of the origin and evolution of supermassive black holes by enabling more precise black hole mass measurements in a mass range that is unreachable today. We present simulations and predictions of the observations of nuclei that will be made with the Thirty Meter Telescope (TMT) and the adaptive optics assisted integral-field spectrograph IRIS, which is capable of diffraction-limited spectroscopy from Z band (0.9 μm)more » to K band (2.2 μm). These simulations, for the first time, use realistic values for the sky, telescope, adaptive optics system, and instrument to determine the expected signal-to-noise ratio of a range of possible targets spanning intermediate mass black holes of ∼10{sup 4} M {sub ☉} to the most massive black holes known today of >10{sup 10} M {sub ☉}. We find that IRIS will be able to observe Milky Way mass black holes out the distance of the Virgo Cluster, and will allow us to observe many more of the brightest cluster galaxies where the most massive black holes are thought to reside. We also evaluate how well the kinematic moments of the velocity distributions can be constrained at the different spectral resolutions and plate scales designed for IRIS. We find that a spectral resolution of ∼8000 will be necessary to measure the masses of intermediate mass black holes. By simulating the observations of galaxies found in Sloan Digital Sky Survey DR7, we find that over 10{sup 5} massive black holes will be observable at distances between 0.005 < z < 0.18 with the estimated sensitivity and angular resolution provided by access to Z-band (0.9 μm) spectroscopy from IRIS and the TMT adaptive optics system. These observations will provide the most accurate dynamical measurements of black hole masses to enable the study of the demography of massive black holes, address the origin of the M {sub BH} – σ and M {sub BH} – L relationships, and evolution of black holes through cosmic time.« less

  6. Evidence for two-loop interaction from IRIS and SDO observations of penumbral brightenings

    NASA Astrophysics Data System (ADS)

    Alissandrakis, C. E.; Koukras, A.; Patsourakos, S.; Nindos, A.

    2017-07-01

    Aims: We investigate small scale energy release events which can provide clues on the heating mechanism of the solar corona. Methods: We analyzed spectral and imaging data from the Interface Region Imaging Spectrograph (IRIS), images from the Atmospheric Imaging Assembly (AIA) aboard the Solar Dynamics Observatoty (SDO), and magnetograms from the Helioseismic and Magnetic Imager (HMI) aboard SDO. Results: We report observations of small flaring loops in the penumbra of a large sunspot on July 19, 2013. Our main event consisted of a loop spanning 15'', from the umbral-penumbral boundary to an opposite polarity region outside the penumbra. It lasted approximately 10 min with a two minute impulsive peak and was observed in all AIA/SDO channels, while the IRIS slit was located near its penumbral footpoint. Mass motions with an apparent velocity of 100 km s-1 were detected beyond the brightening, starting in the rise phase of the impulsive peak; these were apparently associated with a higher-lying loop. We interpret these motions in terms of two-loop interaction. IRIS spectra in both the C II and Si iv lines showed very extended wings, up to about 400 km s-1, first in the blue (upflows) and subsequently in the red wing. In addition to the strong lines, emission was detected in the weak lines of Cl I, O I and C I, as well as in the Mg II triplet lines. Absorption features in the profiles of the C II doublet, the Si iv doublet and the Mg II h and k lines indicate the existence of material with a lower source function between the brightening and the observer. We attribute this absorption to the higher loop and this adds further credibility to the two-loop interaction hypothesis. Tilts were detected in the absorption spectra, as well as in the spectra of Cl I, O I, and C I lines, possibly indicating rotational motions from the untwisting of magnetic flux tubes. Conclusions: We conclude that the absorption features in the C II, Si iv and Mg II profiles originate in a higher-lying, descending loop; as this approached the already activated lower-lying loop, their interaction gave rise to the impulsive peak, the very broad line profiles and the mass motions. Movies associated to Figs. A.1-A.3 are available at http://www.aanda.org

  7. Infrasound Detection of Rocket Launches

    DTIC Science & Technology

    2000-09-01

    infrasound pressure, and λ and µ are the Lame and shear modulii. Seismic data was available from the IRIS data center for the seismic station DWPF ...the bandwidth of interest. Figure 4 shows a recording of STS-93 (07/24/99 04:31:00GMT) at DWPF (97 km). The largest seismic amplitudes are consistent...lasts ~400 seconds. The dominant frequency (~4 Hz) at DWPF is consistent with the long-range infrasound signals observed at DLIAR. Figure 3. Seismic

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

    Bai, X. Y.; Liu, S. Q.; Su, J. T.

    We report a subarcsecond penumbral transient brightening event with the high-spatial resolution observations from the 1.6 m New Solar Telescope (NST), Interface Region Imaging Spectrograph ( IRIS ), and the Solar Dynamics Observatory . The transient brightening, whose thermal energy is in the range of nanoflares, has signatures in the chromosphere, the transient region, and the corona. NST's H α channel reveals the fine structure of the event with a width as narrow as 101 km (0.″14), which is much smaller than the width from the previous observation. The transient brightening lasts for about 3 minutes. It is associated withmore » a redshift of about 17 km s{sup −1}, found in the Si iv 1402.77 Å line and exhibits an inward motion to the umbra with a speed of 87 km s{sup −1}. The small-scale energy released from the event has a multi-temperature component. Spectral analysis of the brightening region from IRIS shows that not only the transition region lines such as Si iv 1402.77 Å and C ii 1334.53 Å, but also the chromospheric Mg ii k 2796.35 Å line are significantly enhanced and broadened. In addition, the event can be found in all the extreme-ultraviolet passbands of the Atmospheric Imaging Assembly and the derived differential emission measure profile increases between 4 and 15 MK (or 6.6 ≤ log T ≤ 7.2) in the transient brightening phase. It is possible that the penumbral transient brightening event is caused by magnetic reconnection.« less

  9. IRISpy: Analyzing IRIS Data in Python

    NASA Astrophysics Data System (ADS)

    Ryan, Daniel; Christe, Steven; Mumford, Stuart; Baruah, Ankit; Timothy, Shelbe; Pereira, Tiago; De Pontieu, Bart

    2017-08-01

    IRISpy is a new community-developed open-source software library for analysing IRIS level 2 data. It is written in Python, a free, cross-platform, general-purpose, high-level programming language. A wide array of scientific computing software packages have already been developed in Python, from numerical computation (NumPy, SciPy, etc.), to visualization and plotting (matplotlib), to solar-physics-specific data analysis (SunPy). IRISpy is currently under development as a SunPy-affiliated package which means it depends on the SunPy library, follows similar standards and conventions, and is developed with the support of of the SunPy development team. IRISpy’s has two primary data objects, one for analyzing slit-jaw imager data and another for analyzing spectrograph data. Both objects contain basic slicing, indexing, plotting, and animating functionality to allow users to easily inspect, reduce and analyze the data. As part of this functionality the objects can output SunPy Maps, TimeSeries, Spectra, etc. of relevant data slices for easier inspection and analysis. Work is also ongoing to provide additional data analysis functionality including derivation of systematic measurement errors (e.g. readout noise), exposure time correction, residual wavelength calibration, radiometric calibration, and fine scale pointing corrections. IRISpy’s code base is publicly available through github.com and can be contributed to by anyone. In this poster we demonstrate IRISpy’s functionality and future goals of the project. We also encourage interested users to become involved in further developing IRISpy.

  10. Ellerman bombs and UV bursts: reconnection at different atmospheric layers?

    NASA Astrophysics Data System (ADS)

    Hansteen, V. H.; Ortiz-Carbonell, A. N.; Rouppe van der Voort, L.

    2017-12-01

    The emergence of magnetic flux through the photosphere and into the outer solar atmosphere produces, amongst many other phenomena, the appearance of Ellerman bombs (EBs) in the photosphere. EBs are observed in the wings of H(alpha) and are highly likely to be due to reconnection in the photosphere, below the chromospheric canopy. However, signs of the reconnection process are also observed in several other spectral lines, typical of the chromosphere or transition region. An example are the UV bursts observed in the transition region lines of Si IV. In this work we analyze high cadence coordinated observations between the 1-m Swedish Solar Telescope and the IRIS spacecraft in order to study the possible relationship between reconnection events at different layers in the atmosphere, and in particular, the timing history between them. High cadence, high resolution H-alpha images from the SST provide us with the positions, timings and trajectories of Ellerman bombs in an emerging flux region. Simultaneous co-aligned IRIS slit-jaw images at 1400 and 1330 A and detailed Si IV spectra from the fast spectrograph raster allow us to study the transition region counterparts of those photospheric Ellerman bombs. Our main goal is to study whether there is a temporal relationship between the appearance of an EB and the appearance of a UV burst. Eventually we would like to investigate whether reconnection happens at discrete heights, or as a reconnection sheet spanning several layers at the same time.

  11. MUSE: the Multi-Slit Solar Explorer

    NASA Astrophysics Data System (ADS)

    Tarbell, Theodore D.; De Pontieu, Bart

    2017-08-01

    The Multi-Slit Solar Explorer is a proposed Small Explorer mission for studying the dynamics of the corona and transition region using both conventional and novel spectral imaging techniques. The physical processes that heat the multi-million degree solar corona, accelerate the solar wind and drive solar activity (CMEs and flares) remain poorly known. A breakthrough in these areas can only come from radically innovative instrumentation and state-of-the-art numerical modeling and will lead to better understanding of space weather origins. MUSE’s multi-slit coronal spectroscopy will use a 100x improvement in spectral raster cadence to fill a crucial gap in our knowledge of Sun-Earth connections; it will reveal temperatures, velocities and non-thermal processes over a wide temperature range to diagnose physical processes that remain invisible to current or planned instruments. MUSE will contain two instruments: an EUV spectrograph (SG) and EUV context imager (CI). Both have similar spatial resolution and leverage extensive heritage from previous high-resolution instruments such as IRIS and the HiC rocket payload. The MUSE investigation will build on the success of IRIS by combining numerical modeling with a uniquely capable observatory: MUSE will obtain EUV spectra and images with the highest resolution in space (1/3 arcsec) and time (1-4 s) ever achieved for the transition region and corona, along 35 slits and a large context FOV simultaneously. The MUSE consortium includes LMSAL, SAO, Stanford, ARC, HAO, GSFC, MSFC, MSU, ITA Oslo and other institutions.

  12. Transition Region and Chromospheric Signatures of Impulsive Heating Events. I. Observations

    NASA Astrophysics Data System (ADS)

    Warren, Harry P.; Reep, Jeffrey W.; Crump, Nicholas A.; Simões, Paulo J. A.

    2016-09-01

    We exploit the high spatial resolution and high cadence of the Interface Region Imaging Spectrograph (IRIS) to investigate the response of the transition region and chromosphere to energy deposition during a small flare. Simultaneous observations from the Reuven Ramaty High Energy Solar Spectroscopic Imager provide constraints on the energetic electrons precipitating into the flare footpoints, while observations of the X-Ray Telescope, Atmospheric Imaging Assembly, and Extreme Ultraviolet Imaging Spectrometer (EIS) allow us to measure the temperatures and emission measures from the resulting flare loops. We find clear evidence for heating over an extended period on the spatial scale of a single IRIS pixel. During the impulsive phase of this event, the intensities in each pixel for the Si IV 1402.770 Å, C II 1334.535 Å, Mg II 2796.354 Å, and O I 1355.598 Å emission lines are characterized by numerous small-scale bursts typically lasting 60 s or less. Redshifts are observed in Si IV, C II, and Mg II during the impulsive phase. Mg II shows redshifts during the bursts and stationary emission at other times. The Si IV and C II profiles, in contrast, are observed to be redshifted at all times during the impulsive phase. These persistent redshifts are a challenge for one-dimensional hydrodynamic models, which predict only short-duration downflows in response to impulsive heating. We conjecture that energy is being released on many small-scale filaments with a power-law distribution of heating rates.

  13. OBSERVATIONS OF MAGNETIC FLUX-ROPE OSCILLATION DURING THE PRECURSOR PHASE OF A SOLAR ERUPTION

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

    Zhou, G. P.; Wang, J. X.; Zhang, J., E-mail: gpzhou@nao.cas.cn, E-mail: wangjx@nao.cas.cn, E-mail: jzhang7@gmu.edu

    2016-05-20

    Based on combined observations from the Interface Region Imaging Spectrograph (IRIS) spectrometer with the coronal emission line of Fe xxi at 1354.08 Å and SDO /AIA images in multiple passbands, we report the finding of the precursor activity manifested as the transverse oscillation of a sigmoid, which is likely a pre-existing magnetic flux rope (MFR), that led to the onset of an X class flare and a fast halo coronal mass ejection (CME) on 2014 September 10. The IRIS slit is situated at a fixed position that is almost vertical to the main axis of the sigmoid structure that hasmore » a length of about 1.8 × 10{sup 5} km. This precursor oscillation lasts for about 13 minutes in the MFR and has velocities in the range of [−9, 11] km s{sup −1} and a period of ∼280 s. Our analysis, which is based on the temperature, density, length, and magnetic field strength of the observed sigmoid, indicates that the nature of the oscillation is a standing wave of fast magnetoacoustic kink mode. We further find that the precursor oscillation is excited by the energy released through an external magnetic reconnection between the unstable MFR and the ambient magnetic field. It is proposed that this precursor activity leads to the dynamic formation of a current sheet underneath the MFR that subsequently reconnects to trigger the onset of the main phase of the flare and the CME.« less

  14. Simulating the Mg II NUV Spectra & C II Resonance Lines During Solar Flares

    NASA Astrophysics Data System (ADS)

    Kerr, Graham Stewart; Allred, Joel C.; Leenaarts, Jorrit; Butler, Elizabeth; Kowalski, Adam

    2017-08-01

    The solar chromosphere is the origin of the bulk of the enhanced radiative output during solar flares, and so comprehensive understanding of this region is important if we wish to understand energy transport in solar flares. It is only relatively recently, however, with the launch of IRIS that we have routine spectroscopic flarea observations of the chromsphere and transition region. Since several of the spectral lines observed by IRIS are optically thick, it is necessary to use forward modelling to extract the useful information that these lines carry about the flaring chromosphere and transition region. We present the results of modelling the formation properties Mg II resonance lines & subordinate lines, and the C II resonance lines during solar flares. We focus on understanding their relation to the physical strucutre of the flaring atmosphere, exploiting formation height differences to determine if we can extract information about gradients in the atmosphere. We show the effect of degrading the profiles to the resolution of the IRIS, and that the usual observational techniques used to identify the line centroid do a poor job in the early stages of the flare (partly due to multiple optically thick line components). Finally, we will tentatively comment on the effects that 3D radiation transfer may have on these lines.

  15. The re-flight of the Colorado high-resolution Echelle stellar spectrograph (CHESS): improvements, calibrations, and post-flight results

    NASA Astrophysics Data System (ADS)

    Hoadley, Keri; France, Kevin; Kruczek, Nicholas; Fleming, Brian; Nell, Nicholas; Kane, Robert; Swanson, Jack; Green, James; Erickson, Nicholas; Wilson, Jacob

    2016-07-01

    In this proceeding, we describe the scientific motivation and technical development of the Colorado High- resolution Echelle Stellar Spectrograph (CHESS), focusing on the hardware advancements and testing supporting the second flight of the payload (CHESS-2). CHESS is a far ultraviolet (FUV) rocket-borne instrument designed to study the atomic-to-molecular transitions within translucent cloud regions in the interstellar medium (ISM). CHESS is an objective f/12.4 echelle spectrograph with resolving power > 100,000 over the band pass 1000 - 1600 Å. The spectrograph was designed to employ an R2 echelle grating with "low" line density. We compare the FUV performance of experimental echelle etching processes (lithographically by LightSmyth, Inc. and etching via electron-beam technology by JPL Microdevices Laboratory) with traditional, mechanically-ruled gratings (Bach Research, Inc. and Richardson Gratings). The cross-dispersing grating, developed and ruled by Horiba Jobin-Yvon, is a holographically-ruled, "low" line density, powered optic with a toroidal surface curvature. Both gratings were coated with aluminum and lithium fluoride (Al+LiF) at Goddard Space Flight Center (GSFC). Results from final efficiency and reflectivity measurements for the optical components of CHESS-2 are presented. CHESS-2 utilizes a 40mm-diameter cross-strip anode readout microchannel plate (MCP) detector fabricated by Sensor Sciences, Inc., to achieve high spatial resolution with high count rate capabilities (global rates 1 MHz). We present pre-flight laboratory spectra and calibration results. CHESS-2 launched on 21 February 2016 aboard NASA/CU sounding rocket mission 36.297 UG. We observed the intervening ISM material along the sightline to epsilon Per and present initial characterization of the column densities, temperature, and kinematics of atomic and molecular species in the observation.

  16. X-ray optics for WHIMex: the Warm Hot Intergalactic Medium Explorer

    NASA Astrophysics Data System (ADS)

    Cash, W.; McEntaffer, R.; Zhang, W.; Casement, S.; Lillie, C.; Schattenburg, M.; Bautz, M.; Holland, A.; Tsunemi, H.; O'Dell, S.

    2011-09-01

    The x-ray astronomy community has never flown a celestial source spectrograph that can resolve natural line widths in absorption the way the ultraviolet community did with OAO-3 Copernicus back in 1972. Yet there is important science to be mined there, and right now, the large flagship missions like the International X-ray Observatory are not progressing toward launch. WHIMEx is an Explorer concept proposed earlier this year to open up that science regime in the next few years. The concept features a modified off-plane grating spectrograph design that will support high resolution (λ/δλ ~ 4000) in the soft x-ray band with a high packing density that will enable a modest cost space mission. We discuss the design and capabilities for the WHIMEx mission. Its prime science goal is detecting high temperature oxygen in the Intergalactic Medium, but it has a broad range of science potential cutting across all of x-ray astronomy and should give us a new window on the Universe.

  17. KSC-08pd2326

    NASA Image and Video Library

    2008-08-07

    CAPE CANAVERAL, Fla. – In the clean room of the Payload Hazardous Processing Facility at NASA's Kennedy Space Center, workers prepare to attach an overhead crane to the Cosmic Origins Spectrograph, or COS. The COS will be lifted and moved to a protective enclosure on the Orbital Replacement Unit Carrier, part of the payload for the fifth and final Hubble servicing mission, STS-125. Other payloads include the Flight Support System, the Super Lightweight Interchangeable Carrier and the Multi-Use Lightweight Equipment, or MULE, carrier. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. The COS far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of Atlantis on the STS-125 mission is targeted for Oct. 8. Photo credit: NASA/Kim Shiflett

  18. KSC-08pd2327

    NASA Image and Video Library

    2008-08-07

    CAPE CANAVERAL, Fla. – In the clean room of the Payload Hazardous Processing Facility at NASA's Kennedy Space Center, workers attach an overhead crane to the Cosmic Origins Spectrograph, or COS. The COS is being lifted and moved to a protective enclosure on the Orbital Replacement Unit Carrier, part of the payload for the fifth and final Hubble servicing mission, STS-125. Other payloads include the Flight Support System, the Super Lightweight Interchangeable Carrier and the Multi-Use Lightweight Equipment, or MULE, carrier. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. The COS far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of Atlantis on the STS-125 mission is targeted for Oct. 8. Photo credit: NASA/Kim Shiflett

  19. KSC-08pd2330

    NASA Image and Video Library

    2008-08-07

    CAPE CANAVERAL, Fla. – In the clean room of the Payload Hazardous Processing Facility at NASA's Kennedy Space Center, an overhead crane lifts the Cosmic Origins Spectrograph, or COS. The COS is being lifted and moved to a protective enclosure on the Orbital Replacement Unit Carrier, part of the payload for the fifth and final Hubble servicing mission, STS-125. Other payloads include the Flight Support System, the Super Lightweight Interchangeable Carrier and the Multi-Use Lightweight Equipment, or MULE, carrier. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. The COS far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of Atlantis on the STS-125 mission is targeted for Oct. 8. Photo credit: NASA/Kim Shiflett

  20. KSC-08pd2331

    NASA Image and Video Library

    2008-08-07

    CAPE CANAVERAL, Fla. – In the clean room of the Payload Hazardous Processing Facility at NASA's Kennedy Space Center, an overhead crane lifts the Cosmic Origins Spectrograph, or COS. The COS is being lifted and moved to a protective enclosure on the Orbital Replacement Unit Carrier, part of the payload for the fifth and final Hubble servicing mission, STS-125. Other payloads include the Flight Support System, the Super Lightweight Interchangeable Carrier and the Multi-Use Lightweight Equipment, or MULE, carrier. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. The COS far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of Atlantis on the STS-125 mission is targeted for Oct. 8. Photo credit: NASA/Kim Shiflett

  1. KSC-08pd2328

    NASA Image and Video Library

    2008-08-07

    CAPE CANAVERAL, Fla. – In the clean room of the Payload Hazardous Processing Facility at NASA's Kennedy Space Center, an overhead crane lifts the Cosmic Origins Spectrograph, or COS. The COS is being lifted and moved to a protective enclosure on the Orbital Replacement Unit Carrier, part of the payload for the fifth and final Hubble servicing mission, STS-125. Other payloads include the Flight Support System, the Super Lightweight Interchangeable Carrier and the Multi-Use Lightweight Equipment, or MULE, carrier. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. The COS far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of Atlantis on the STS-125 mission is targeted for Oct. 8. Photo credit: NASA/Kim Shiflett

  2. KSC-08pd2318

    NASA Image and Video Library

    2008-08-06

    CAPE CANAVERAL, Fla. – In the clean room of the Payload Hazardous Processing Facility at NASA's Kennedy Space Center, workers from NASA's Goddard Space Flight Center use black light inspection for a thorough cleaning of the protective carrier for the Cosmic Origins Spectrograph, or COS. Black light inspection uses UVA fluorescence to detect possible particulate microcontamination, minute cracks or fluid leaks. The COS will be installed on the Hubble Space Telescope on space shuttle Atlantis' STS-125 mission. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. The COS far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of Atlantis on the STS-125 mission is targeted for Oct. 8. Photo credit: NASA/Kim Shiflett

  3. KSC-08pd2319

    NASA Image and Video Library

    2008-08-06

    CAPE CANAVERAL, Fla. – In the clean room of the Payload Hazardous Processing Facility at NASA's Kennedy Space Center, workers from NASA's Goddard Space Flight Center use black light inspection for a thorough cleaning of the protective carrier for the Cosmic Origins Spectrograph, or COS. Black light inspection uses UVA fluorescence to detect possible particulate microcontamination, minute cracks or fluid leaks. The COS will be installed on the Hubble Space Telescope on space shuttle Atlantis' STS-125 mission. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. The COS far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of Atlantis on the STS-125 mission is targeted for Oct. 8. Photo credit: NASA/Kim Shiflett

  4. KSC-08pd2329

    NASA Image and Video Library

    2008-08-07

    CAPE CANAVERAL, Fla. – In the clean room of the Payload Hazardous Processing Facility at NASA's Kennedy Space Center, an overhead crane lifts the Cosmic Origins Spectrograph, or COS. The COS is being lifted and moved to a protective enclosure on the Orbital Replacement Unit Carrier, part of the payload for the fifth and final Hubble servicing mission, STS-125. Other payloads include the Flight Support System, the Super Lightweight Interchangeable Carrier and the Multi-Use Lightweight Equipment, or MULE, carrier. COS will be the most sensitive ultraviolet spectrograph ever flown on Hubble and will probe the "cosmic web" - the large-scale structure of the universe whose form is determined by the gravity of dark matter and is traced by galaxies and intergalactic gas. The COS far-ultraviolet channel has a sensitivity 30 times greater than that of previous spectroscopic instruments for the detection of extremely low light levels. Launch of Atlantis on the STS-125 mission is targeted for Oct. 8. Photo credit: NASA/Kim Shiflett

  5. Narrow-band EUV Multilayer Coating for the MOSES Sounding Rocket

    NASA Technical Reports Server (NTRS)

    Owens, Scott M.; Gum, Jeffery S.; Tarrio, Charles; Dvorak, Joseph; Kjornrattanawanich, Benjawan; Keski-Kuha, Ritva; Thomas, Roger J.; Kankelborg, Charles C.

    2005-01-01

    The Multi-order Solar EUV Spectrograph (MOSES) is a slitless spectrograph designed to study solar He II emission at 303.8 Angstroms, to be launched on a sounding rocket payload. One difference between MOSES and other slitless spectrographs is that the images are recorded simultaneously at three spectral orders, m = -1,0, +l. Another is the addition of a narrow-band multilayer coating on both the grating and the fold flat, which will reject out-of-band lines that normally contaminate the image of a slitless instrument. The primary metrics f a the mating were high peak reflectivity and suppression of Fe XV and XVI emission lines at 284 Angstroms and 335 Angstroms, respectively. We chose B4C/Mg2Si for our material combination since it provides better values for all three metrics together than the other leading candidates Si/Ir, Si/B4C or Si/SiC. Measurements of witness flats at NIST indicate the peak reflectivity at 303.6 is 38.5% for a 15 bilayer stack, while the suppression at 284 Angstroms, is 4.5x and at 335 Angstroms is 18.3x for each of two reflections in the instrument. We present the results of coating the MOSES flight gratings and fold flat, including the spectral response of the fold flat and grating as measured at NIST's SURF III and Brookhaven's X24C beamline.

  6. High Resolution Spectroscopy in the Far UV: Observations of the Interstellar Medium by IMAPS on ORFEUS-SPAS

    NASA Astrophysics Data System (ADS)

    Jenkins, Edward B.; Reale, Michael A.; Zucchino, Paul M.; Sofia, Ulysses J.

    1996-09-01

    The Interstellar Medium Absorption Profile Spectrograph (IMAPS) is an objectivegrating, echelle spectrograph built to observe the spectra of bright, hot stars over the spectral region 950 1150Å, below the wavelength coverage of HST. This instrument has a high wavelength resolving power, making it especially well suited for studies of interstellar absorption lines. Following a series of sounding rocket flights in the 1980's, IMAPS flew on its first Shuttle-launched orbital mission in September 1993, as a partner in the ORFEUS-SPAS program sponsored by the US and German Space Agencies, NASA and DARA. On ORFEUS-SPAS, IMAPS spent one day of orbital time observing the spectra of 10 O- and early B-type stars. In addition to outlining how IMAPS works, we document some special problems that had an influence on the data, and we explain the specific steps in data reduction that were employed to overcome them. This discussion serves as a basic source of information for people who may use archival data from this flight, as well as those who are interested in some specific properties of the data that will be presented in forthcoming research papers. IMAPS is scheduled to fly once again on ORFEUS-SPAS in late 1996. On this flight, 50% of the observing time available for IMAPS and two other spectrographs on the mission will be available to guest observers.

  7. Goddard High Resolution Spectrograph SV/GTO Project

    NASA Technical Reports Server (NTRS)

    Ebbets, Dennis

    1999-01-01

    Contract number NAS5-30433, known at Ball Aerospace as the GHRS SV/GTO project, supported our participation in the post-launch activities of the Goddard High Resolution Spectrograph aboard the Hubble Space Telescope. The period of performance was December 1988 through December 1998. The contract supported the involvement of Dr Dennis Ebbets in the work of the GHRS Investigation Definition Team, and several of the Ball people in the documentation and publication of results. Three main categories of tasks were covered by this contract; in-orbit calibration of the GHRS, guaranteed time observations, and education and public outreach. The nature and accomplishments of these tasks are described in the report. This summary makes many references to publications in the scientific and technical literature. Appendix A is extracted from a complete bibliography, and lists those papers that are directly related to work performed under this GHRS contract. The tasks related to the in-orbit calibration of the GHRS were by far the largest responsibility during the first six years of the project. During this period Dr. Ebbets was responsible for the definition of calibration requirements, design of experiments, preparation of observing proposals, tracking their implementation and execution, and coordinating the analysis and publication of the results. Prior to the launch of HST in 1990 the observing proposals were developed in cooperation with the scientists on the GHRS DDT, engineers at Ball Aerospace, the operations staff at the STScI, and project coordinators at GSFC.

  8. Flight Avionics Sequencing Telemetry (FAST) DIV Latching Display

    NASA Technical Reports Server (NTRS)

    Moore, Charlotte

    2010-01-01

    The NASA Engineering (NE) Directorate at Kennedy Space Center provides engineering services to major programs such as: Space Shuttle, Inter national Space Station, and the Launch Services Program (LSP). The Av ionics Division within NE, provides avionics and flight control syste ms engineering support to LSP. The Launch Services Program is respons ible for procuring safe and reliable services for transporting critical, one of a kind, NASA payloads into orbit. As a result, engineers mu st monitor critical flight events during countdown and launch to asse ss anomalous behavior or any unexpected occurrence. The goal of this project is to take a tailored Systems Engineering approach to design, develop, and test Iris telemetry displays. The Flight Avionics Sequen cing Telemetry Delta-IV (FAST-D4) displays will provide NASA with an improved flight event monitoring tool to evaluate launch vehicle heal th and performance during system-level ground testing and flight. Flight events monitored will include data from the Redundant Inertial Fli ght Control Assembly (RIFCA) flight computer and launch vehicle comma nd feedback data. When a flight event occurs, the flight event is ill uminated on the display. This will enable NASA Engineers to monitor c ritical flight events on the day of launch. Completion of this project requires rudimentary knowledge of launch vehicle Guidance, Navigatio n, and Control (GN&C) systems, telemetry, and console operation. Work locations for the project include the engineering office, NASA telem etry laboratory, and Delta launch sites.

  9. 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.

  10. Global 3-D ionospheric electron density reanalysis based on multisource data assimilation

    NASA Astrophysics Data System (ADS)

    Yue, Xinan; Schreiner, William S.; Kuo, Ying-Hwa; Hunt, Douglas C.; Wang, Wenbin; Solomon, Stanley C.; Burns, Alan G.; Bilitza, Dieter; Liu, Jann-Yenq; Wan, Weixing; Wickert, Jens

    2012-09-01

    We report preliminary results of a global 3-D ionospheric electron density reanalysis demonstration study during 2002-2011 based on multisource data assimilation. The monthly global ionospheric electron density reanalysis has been done by assimilating the quiet days ionospheric data into a data assimilation model constructed using the International Reference Ionosphere (IRI) 2007 model and a Kalman filter technique. These data include global navigation satellite system (GNSS) observations of ionospheric total electron content (TEC) from ground-based stations, ionospheric radio occultations by CHAMP, GRACE, COSMIC, SAC-C, Metop-A, and the TerraSAR-X satellites, and Jason-1 and 2 altimeter TEC measurements. The output of the reanalysis are 3-D gridded ionospheric electron densities with temporal and spatial resolutions of 1 h in universal time, 5° in latitude, 10° in longitude, and ˜30 km in altitude. The climatological features of the reanalysis results, such as solar activity dependence, seasonal variations, and the global morphology of the ionosphere, agree well with those in the empirical models and observations. The global electron content derived from the international GNSS service global ionospheric maps, the observed electron density profiles from the Poker Flat Incoherent Scatter Radar during 2007-2010, and foF2 observed by the global ionosonde network during 2002-2011 are used to validate the reanalysis method. All comparisons show that the reanalysis have smaller deviations and biases than the IRI-2007 predictions. Especially after April 2006 when the six COSMIC satellites were launched, the reanalysis shows significant improvement over the IRI predictions. The obvious overestimation of the low-latitude ionospheric F region densities by the IRI model during the 23/24 solar minimum is corrected well by the reanalysis. The potential application and improvements of the reanalysis are also discussed.

  11. Extending the reanalysis to the ionosphere based on ground and LEO based GNSS observations

    NASA Astrophysics Data System (ADS)

    Yue, X.; Schreiner, W. S.; Kuo, Y.

    2012-12-01

    We report preliminary results of a global 3-D ionospheric electron density reanalysis during 2002-2011 based on multi-source data assimilation. The monthly global ionospheric electron density reanalysis has been done by assimilating the quiet days ionospheric data into a data assimilation model constructed using the International Reference Ionosphere (IRI) 2007 model and a Kalman filter technique. These data include global navigation satellite system (GNSS) observations of ionospheric total electron content (TEC) from ground based stations, ionospheric radio occultations by CHAMP, GRACE, COSMIC, SAC-C, Metop-A, and the TerraSAR-X satellites, and Jason-1 and 2 altimeter TEC measurements. The output of the reanalysis are 3-D gridded ionospheric electron densities with temporal and spatial resolutions of 1 hr in universal time, 5o in latitude, 10o in longitude, and ~ 30 km in altitude. The climatological features of the reanalysis results, such as solar activity dependence, seasonal variations, and the global morphology of the ionosphere, agree well with those in the empirical models and observations. The global electron content (GEC) derived from the international GNSS service (IGS) global ionospheric maps (GIM), the observed electron density profiles from the Poker Flat Incoherent Scatter Radar (PFISR) during 2007-2010, and foF2 observed by the global ionosonde network during 2002-2011 are used to validate the reanalysis method. All comparisons show that the reanalysis have smaller deviations and biases than the IRI-2007 predictions. Especially after April 2006 when the six COSMIC satellites were launched, the reanalysis shows significant improvement over the IRI predictions. The obvious overestimation of the low-latitude ionospheric F-region densities by the IRI model during the 23/24 solar minimum is corrected well by the reanalysis. The potential application and improvements of the reanalysis are also discussed.

  12. JWST Near-Infrared Detectors: Latest Test Results

    NASA Technical Reports Server (NTRS)

    Smith, Erin C.; Rauscher, Bernard J.; Alexander, David; Brambora, Clifford K.; Chiao, Meng; Clemons, Brian L.; Derro, Rebecca; Engler, Chuck; Fox, Ori; Garrison, Matthew B.; hide

    2009-01-01

    The James Webb Space Telescope, an infrared-optimized space telescope being developed by NASA for launch in 2013, will utilize cutting-edge detector technology in its investigation of fundamental questions in astrophysics. JWST's near infrared spectrograph, NIRSpec utilizes two 2048 x 2048 HdCdTe arrays with Sidecar ASIC readout electronics developed by Teledyne to provide spectral coverage from 0.6 microns to 5 microns. We present recent test and calibration results for the NIRSpec flight arrays as well as data processing routines for noise reduction and cosmic ray rejection.

  13. Earth Science

    NASA Image and Video Library

    1996-01-31

    The Near Earth Asteroid Rendezvous (NEAR) spacecraft embarks on a journey that will culminate in a close encounter with an asteroid. The launch of NEAR inaugurates NASA's irnovative Discovery program of small-scale planetary missions with rapid, lower-cost development cycles and focused science objectives. NEAR will rendezvous in 1999 with the asteroid 433 Eros to begin the first long-term, close-up look at an asteroid's surface composition and physical properties. NEAR's science payload includes an x-ray/gamma ray spectrometer, an near-infrared spectrograph, a laser rangefinder, a magnetometer, a radio science experiment and a multi-spectral imager.

  14. The Behavior of Warm Molecules in Planet-forming Disks and CHESS: a Pathfinder UV Spectrograph for the LUVOIR Surveyor

    NASA Astrophysics Data System (ADS)

    Hoadley, Keri; France, Kevin

    2017-01-01

    Understanding the evolution of gas over the lifetime of protoplanetary disks provides us with important clues about how planet formation mechanisms drive the diversity of exoplanetary systems observed to date. In the first part of my talk, I will discuss how we use emission line observations of molecular hydrogen (H2) in the far-ultraviolet (far-UV) with the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope to study the warm molecular regions (a < 10 AU) of planet-forming disks. We compare the observations with analytic disk models that produce synthetic H2 profiles, and we statistically determine the disk representations that best replicate the data. I will discuss the results of our comparisons and how the modeled radial distributions of H2 in the disk help provide important constraints on the effective density of gas left in the inner disk of protoplanetary disks at various disk evolutionary stages. Finally, I will talk about follow-up studies that look to connect the warm, UV-pumped molecular populations of the inner disk to thermally-excited molecules observed in similar regions of the disk in the near- to mid-IR.In the second part of my talk, I will discuss the observational requirements in the UV and IR band passes to gain further insights into the behavior of the warm, gaseous protoplanetary disk, focusing specifically on a spectrograph concept for the next-generation LUVOIR Surveyor. I will discuss a testbed instrument, the Colorado High-resolution Echelle Stellar Spectrograph (CHESS), built as a demonstration of one component of the LUVOIR spectrograph and new technological improvements to UV optical components for the next generation of near- to far-UV astrophysical observatories. CHESS is a far-UV sounding rocket experiment designed to probe the warm and cool atoms and molecules near sites of recent star formation in the local interstellar medium. I will talk about the science goals, design, research and development (R&D) components, and calibration of the CHESS instrument. I will end by presenting the initial data reduction and results of the flight observations taken during the second launch of CHESS.

  15. Coordinated Ground- and Space-based Multispectral Campaign to Study Equatorial Spread-F Formation

    NASA Astrophysics Data System (ADS)

    Finn, S. C.; Geddes, G.; Aryal, S.; Stephan, A. W.; Budzien, S. A.; Duggirala, P. R.; Chakrabarti, S.; Valladares, C.

    2016-12-01

    We present a concept for a multispectral campaign using coordinated data from state-of-the-art instruments aboard the International Space Station (ISS) and multiple ground-based spectrometers and digisondes deployed at low-latitudes to study the formation and development of Equatorial Spread-F (ESF). This extended observational campaign utilizes ultraviolet, visible, and radio measurements to develop a predictive capability for ESF and to study the coupling of the ionosphere-thermosphere (I-T) system during geomagnetically quiet and disturbed times. The ground-based instruments will be deployed in carefully chosen locations in the American and Indian sectors while the space-based data will provide global coverage spanning all local times and longitudes within ±51° geographic latitudes. The campaign, over an extended period covering a range of geophysical conditions, will provide the extensive data base necessary to address the important science questions. The space-based instrument suite consists of the Limb-imaging Ionospheric and Thermospheric Extreme-ultraviolet Spectrograph (LITES) and the GPS Radio Occultation and Ultraviolet Photometry-Colocated (GROUP-C) instruments, scheduled to launch to the ISS in November 2016. LITES is a compact imaging spectrograph for remote sensing of the upper atmosphere and ionosphere from 60 to 140nm and GROUP-C has a nadir-viewing FUV photometer. The ground-based instruments to be deployed for this campaign are three high-resolution imaging spectrographs capable of continuous round-the-clock airglow observations: Multiwavelength Imaging Spectrograph using Echelle grating (MISE) in India and two High Throughput and Multi-slit Imaging Spectrographs (HiT&MIS) to be deployed in Colombia and Argentina, the Low-Latitude Ionosphere Sensor Network (LISN), and the Global Ionospheric Radio Observatory (GIRO) digisondes network. We present data from the ground-based instruments, initial results from the LITES and GROUP-C instruments on-orbit, and modeling and analysis methods for the campaign. This work was supported by NSF 1315354 and 1145166, and ONR N00014-13-1-0266 grants. LITES and GROUP-C are part of the STP-H5 Payload, integrated and flown under the direction of the DoD Space Test Program.

  16. Chromospheric Heating Driven by Cancellations of Internetwork Magnetic Flux

    NASA Astrophysics Data System (ADS)

    Gosic, M.; de la Cruz Rodriguez, J.; De Pontieu, B.; Bellot Rubio, L.; Esteban Pozuelo, S.; Ortiz-Carbonell, A. N.

    2017-12-01

    The heating of the solar chromosphere remains to be one of the most important questions in solar physics. It is believed that this phenomenon may significantly be supported by small-scale internetwork (IN) magnetic fields. Indeed, cancellations of IN magnetic flux can generate transient brightenings in the chromosphere and transition region. These bright structures might be the signature of energy release and plasma heating, probably driven by magnetic reconnection of IN field lines. Using high resolution, multiwavelength, coordinated observations recorded with the Interface Region Imaging Spectrograph (IRIS) and the Swedish 1-m Solar Telescope (SST), we analyzed cancellations of IN flux and their impact on the energetics and dynamics of the quiet Sun atmosphere. From their temporal and spatial evolution, we determine that these events can heat locally the upper atmospheric layers. However, employing multi-line inversions of the Mg II h & k lines, we show that cancellations, although occurring ubiquitously over IN regions, are not capable of sustaining the total radiative losses of the quiet Sun chromosphere.

  17. The Duration of Energy Deposition on Unresolved Flaring Loops in the Solar Corona

    NASA Astrophysics Data System (ADS)

    Reep, Jeffrey W.; Polito, Vanessa; Warren, Harry P.; Crump, Nicholas A.

    2018-04-01

    Solar flares form and release energy across a large number of magnetic loops. The global parameters of flares, such as the total energy released, duration, physical size, etc., are routinely measured, and the hydrodynamics of a coronal loop subjected to intense heating have been extensively studied. It is not clear, however, how many loops comprise a flare, nor how the total energy is partitioned between them. In this work, we employ a hydrodynamic model to better understand the energy partition by synthesizing Si IV and Fe XXI line emission and comparing to observations of these lines with the Interface Region Imaging Spectrograph (IRIS). We find that the observed temporal evolution of the Doppler shifts holds important information on the heating duration. To demonstrate this, we first examine a single loop model, and find that the properties of chromospheric evaporation seen in Fe XXI can be reproduced by loops heated for long durations, while persistent redshifts seen in Si IV cannot be reproduced by any single loop model. We then examine a multithreaded model, assuming both a fixed heating duration on all loops and a distribution of heating durations. For a fixed heating duration, we find that durations of 100–200 s do a fair job of reproducing both the red- and blueshifts, while a distribution of durations, with a median of about 50–100 s, does a better job. Finally, we compare our simulations directly to observations of an M-class flare seen by IRIS, and find good agreement between the modeled and observed values given these constraints.

  18. Statistical Investigation of Supersonic Downflows in the Transition Region above Sunspots

    NASA Astrophysics Data System (ADS)

    Samanta, Tanmoy; Tian, Hui; Prasad Choudhary, Debi

    2018-06-01

    Downflows at supersonic speeds have been observed in the transition region (TR) above sunspots for more than three decades. These downflows are often seen in different TR spectral lines above sunspots. We have performed a statistical investigation of these downflows using a large sample that was missing previously. The Interface Region Imaging Spectrograph (IRIS) has provided a wealth of observational data of sunspots at high spatial and spectral resolutions in the past few years. We have identified 60 data sets obtained with IRIS raster scans. Using an automated code, we identified the locations of strong downflows within these sunspots. We found that around 80% of our sample shows supersonic downflows in the Si IV 1403 Å line. These downflows mostly appear in the penumbral regions, though some of them are found in the umbrae. We also found that almost half of these downflows show signatures in chromospheric lines. Furthermore, a detailed spectral analysis was performed by selecting a small spectral window containing the O IV 1400/1401 Å and Si IV 1403 Å lines. Six Gaussian functions were simultaneously fitted to these three spectral lines and their satellite lines associated with the supersonic downflows. We calculated the intensity, Doppler velocity, and line width for these lines. Using the O IV 1400/1401 Å line ratio, we find that the downflow components are around one order of magnitude less dense than the regular components. Results from our statistical analysis suggest that these downflows may originate from the corona and that they are independent of the background TR plasma.

  19. Spectral and Imaging Observations of a Current Sheet Region in a Small-scale Magnetic Reconnection Event

    NASA Astrophysics Data System (ADS)

    Xue, Zhike; Yan, Xiaoli; Yang, Liheng; Wang, Jincheng; Feng, Song; Li, Qiaoling; Ji, Kaifan; Zhao, Li

    2018-05-01

    We report a possible current sheet region associated with a small-scale magnetic reconnection event by using the spectral and imaging observations of the Interface Region Imaging Spectrograph (IRIS) and the magnetograms obtained by the Solar Dynamics Observatory on 2016 August 08. The length and width of the current sheet region are estimated to be from 1.4 ± 0.1 Mm to 3.0 ± 0.3 Mm and from 0.34 ± 0.01 Mm to 0.64 ± 0.09 Mm, respectively. The evolutions of the length of the current sheet region are positively correlated with that of the width. These measurements are among the smallest reported. When the IRIS slit scans the current sheet region, the spectroscopic observations show that the Si IV line is broadened in the current sheet region and the plasma has a blueshifted feature at the middle and a redshifted feature at the ends of the current sheet region. The maximum measured blueshifted and redshifted Doppler velocities are ‑20.8 ± 0.9 and 34.1 ± 0.4 km s‑1, respectively. Additionally, the electron number densities of the plasma in the current sheet region are computed to be around 1011 cm‑3 based on the spectrums of the two O IV lines. The emergence, movement, and cancellation of a small sunspot with negative polarity are observed during the formation and shift of the current sheet region. We suggest that the occurrence and evolution of the magnetic reconnection are driven by the movement of the small sunspot in the photosphere.

  20. Mass and energy supply of a cool coronal loop near its apex

    NASA Astrophysics Data System (ADS)

    Yan, Limei; Peter, Hardi; He, Jiansen; Xia, Lidong; Wang, Linghua

    2018-03-01

    Context. Different models for the heating of solar corona assume or predict different locations of the energy input: concentrated at the footpoints, at the apex, or uniformly distributed. The brightening of a loop could be due to the increase in electron density ne, the temperature T, or a mixture of both. Aim. We investigate possible reasons for the brightening of a cool loop at transition region temperatures through imaging and spectral observation. Methods: We observed a loop with the Interface Region Imaging Spectrograph (IRIS) and used the slit-jaw images together with spectra taken at a fixed slit position to study the evolution of plasma properties in and below the loop. We used spectra of Si IV, which forms at around 80 000 K in equilibrium, to identify plasma motions and derive electron densities from the ratio of inter-combination lines of O IV. Additional observations from the Solar Dynamics Observatory (SDO) were employed to study the response at coronal temperatures (Atmospheric Imaging Assembly, AIA) and to investigate the surface magnetic field below the loop (Helioseismic and Magnetic Imager, HMI). Results: The loop first appears at transition region temperatures and later also at coronal temperatures, indicating a heating of the plasma in the loop. The appearance of hot plasma in the loop coincides with a possible accelerating upflow seen in Si IV, with the Doppler velocity shifting continuously from -70 km s-1 to -265 km s-1. The 3D magnetic field lines extrapolated from the HMI magnetogram indicate possible magnetic reconnection between small-scale magnetic flux tubes below or near the loop apex. At the same time, an additional intensity enhancement near the loop apex is visible in the IRIS slit-jaw images at 1400 Å. These observations suggest that the loop is probably heated by the interaction between the loop and the upflows, which are accelerated by the magnetic reconnection between small-scale magnetic flux tubes at lower altitudes. Before and after the possible heating phase, the intensity changes in the optically thin (Si IV) and optical thick line (C II) are mainly contributed by the density variation without significant heating. Conclusions: We therefore provide evidence for the heating of an envelope loop that is affected by accelerating upflows, which are probably launched by magnetic reconnection between small-scale magnetic flux tubes underneath the envelope loop. This study emphasizes that in the complex upper atmosphere of the Sun, the dynamics of the 3D coupled magnetic field and flow field plays a key role in thermalizing 1D structures such as coronal loops. An animation associated to Fig. 1 is available at http://https://www.aanda.org

  1. PRAXIS: low thermal emission high efficiency OH suppressed fibre spectrograph

    NASA Astrophysics Data System (ADS)

    Content, Robert; Bland-Hawthorn, Joss; Ellis, Simon; Gers, Luke; Haynes, Roger; Horton, Anthony; Lawrence, Jon; Leon-Saval, Sergio; Lindley, Emma; Min, Seong-Sik; Shortridge, Keith; Staszak, Nick; Trinh, Christopher; Xavier, Pascal; Zhelem, Ross

    2014-07-01

    PRAXIS is a second generation instrument that follows on from GNOSIS, which was the first instrument using fibre Bragg gratings for OH suppression to be deployed on a telescope. The Bragg gratings reflect the NIR OH lines while being transparent to the light between the lines. This gives in principle a much higher signal-noise ratio at low resolution spectroscopy but also at higher resolutions by removing the scattered wings of the OH lines. The specifications call for high throughput and very low thermal and detector noise so that PRAXIS will remain sky noise limited even with the low sky background levels remaining after OH suppression. The optical and mechanical designs are presented. The optical train starts with fore-optics that image the telescope focal plane on an IFU which has 19 hexagonal microlenses each feeding a multi-mode fibre. Seven of these fibres are attached to a fibre Bragg grating OH suppression system while the others are reference/acquisition fibres. The light from each of the seven OH suppression fibres is then split by a photonic lantern into many single mode fibres where the Bragg gratings are imprinted. Another lantern recombines the light from the single mode fibres into a multi-mode fibre. A trade-off was made in the design of the IFU between field of view and transmission to maximize the signal-noise ratio for observations of faint, compact objects under typical seeing. GNOSIS used the pre-existing IRIS2 spectrograph while PRAXIS will use a new spectrograph specifically designed for the fibre Bragg grating OH suppression and optimised for 1.47 μm to 1.7 μm (it can also be used in the 1.09 μm to 1.26 μm band by changing the grating and refocussing). This results in a significantly higher transmission due to high efficiency coatings, a VPH grating at low incident angle and optimized for our small bandwidth, and low absorption glasses. The detector noise will also be lower thanks to the use of a current generation HAWAII-2RG detector. Throughout the PRAXIS design, from the fore-optics to the detector enclosure, special care was taken at every step along the optical path to reduce thermal emission or stop it leaking into the system. The spectrograph design itself was particularly challenging in this aspect because practical constraints required that the detector and the spectrograph enclosures be physically separate with air at ambient temperature between them. At present, the instrument uses the GNOSIS fibre Bragg grating OH suppression unit. We intend to soon use a new OH suppression unit based on multicore fibre Bragg gratings which will allow an increased field of view per fibre. Theoretical calculations show that the gain in interline sky background signal-noise ratio over GNOSIS may very well be as high as 9 with the GNOSIS OH suppression unit and 17 with the multicore fibre OH suppression unit.

  2. Comparing UV/EUV line parameters and magnetic field in a quiescent prominence with tornadoes

    NASA Astrophysics Data System (ADS)

    Levens, P. J.; Labrosse, N.; Schmieder, B.; López Ariste, A.; Fletcher, L.

    2017-10-01

    Context. Understanding the relationship between plasma and the magnetic field is important for describing and explaining the observed dynamics of solar prominences. Aims: We determine if a close relationship can be found between plasma and magnetic field parameters, measured at high resolution in a well-observed prominence. Methods: A prominence observed on 15 July 2014 by the Interface Region Imaging Spectrograph (IRIS), Hinode, the Solar Dynamics Observatory (SDO), and the Télescope Héliographique pour l'Étude du Magnétisme et des Instabilités Solaires (THEMIS) is selected. We perform a robust co-alignment of data sets using a 2D cross-correlation technique. Magnetic field parameters are derived from spectropolarimetric measurements of the He I D3 line from THEMIS. Line ratios and line-of-sight velocities from the Mg II h and k lines observed by IRIS are compared with magnetic field strength, inclination, and azimuth. Electron densities are calculated using Fe xii line ratios from the Hinode Extreme-ultraviolet Imaging Spectrometer, which are compared to THEMIS and IRIS data. Results: We find Mg II k/h ratios of around 1.4 everywhere, similar to values found previously in prominences. Also, the magnetic field is strongest ( 30 G) and predominantly horizontal in the tornado-like legs of the prominence. The k3 Doppler shift is found to be between ±10 km s-1 everywhere. Electron densities at a temperature of 1.5 × 106 K are found to be around 109 cm-3. No significant correlations are found between the magnetic field parameters and any of the other plasma parameters inferred from spectroscopy, which may be explained by the large differences in the temperatures of the lines used in this study. Conclusions: This is the first time that a detailed statistical study of plasma and magnetic field parameters has been performed at high spatial resolution in a prominence. Our results provide important constraints on future models of the plasma and magnetic field in these structures.

  3. EXPLOSIVE EVENTS ON A SUBARCSECOND SCALE IN IRIS OBSERVATIONS: A CASE STUDY

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

    Huang, Zhenghua; Xia, Lidong; Fu, Hui

    We present a study of a typical explosive event (EE) at subarcsecond scale witnessed by strong non-Gaussian profiles with blue- and redshifted emission of up to 150 km s{sup –1} seen in the transition region Si IV 1402.8 Å, and the chromospheric Mg II k 2796.4 Å and C II 1334.5 Å observed by the Interface Region Imaging Spectrograph (IRIS) at unprecedented spatial and spectral resolution. For the first time an EE is found to be associated with very small-scale (∼120 km wide) plasma ejection followed by retraction in the chromosphere. These small-scale jets originate from a compact bright-point-like structure of ∼1.''5 size as seen in themore » IRIS 1330 Å images. SDO/AIA and SDO/HMI co-observations show that the EE lies in the footpoint of a complex loop-like brightening system. The EE is detected in the higher temperature channels of AIA 171 Å, 193 Å, and 131 Å, suggesting that it reaches a higher temperature of log T = 5.36 ± 0.06 (K). Brightenings observed in the AIA channels with durations 90-120 s are probably caused by the plasma ejections seen in the chromosphere. The wings of the C II line behave in a similar manner to the Si IV'S, indicating close formation temperatures, while the Mg II k wings show additional Doppler-shifted emission. Magnetic convergence or emergence followed by cancellation at a rate of 5 × 10{sup 14} Mx s{sup –1} is associated with the EE region. The combined changes of the locations and the flux of different magnetic patches suggest that magnetic reconnection must have taken place. Our results challenge several theories put forward in the past to explain non-Gaussian line profiles, i.e., EEs. Our case study on its own, however, cannot reject these theories; thus, further in-depth studies on the phenomena producing EEs are required.« less

  4. The cyclotron energization through auroral wave experiments (CENTAUR 2B)

    NASA Technical Reports Server (NTRS)

    Winningham, J. D.

    1992-01-01

    The CENTAUR 2B mission, a dual payload program, is in many aspects the same as the previous missions from Cape Perry and Norway in 1985. It was planned that these payloads would be launched from Andoya, Norway, Nov. 1989 from the Universal II launcher. The payloads are identical, but would have been launched at different azimuths as far north and as far west as possible. Particle experiments include the angular resolving energy analyzer (AREA), the fast ion mass spectrometer (FIMS), the spectrographic particle images (SPI), and finally, the differential ion flux probe (DIFP). SwRI was responsible for the scientific payload, which includes the power supplies, the power supply interfacing, the manipulating of the data from the instruments to format it for the telemetry system, all mechanical structure and restraint mechanisms, and the payload subskin. The status of the various components of this program is given.

  5. STS-85 Mission Specialist Robinson prepares to enter Discovery

    NASA Technical Reports Server (NTRS)

    1997-01-01

    STS-85 Mission Specialist Stephen K. Robinson prepares to enter the Space Shuttle orbiter Discovery at Launch Complex 39A just prior to launch, scheduled for 10:41 a.m. EDT. The primary payload on this mission is the Cryogenic Infrared Spectrometers and Telescopes for the Atmosphere-Shuttle Pallet Satellite-2 (CRISTA-SPAS-2) free-flyer. The CRISTA-SPAS-2 will be deployed on flight day 1 to study trace gases in the Earths atmosphere as a part of NASAs Mission to Planet Earth program. Also aboard the free-flying research platform will be the Middle Atmosphere High Resolution Spectrograph Instrument (MAHRSI). Other payloads on the 11-day mission include the Manipulator Flight Demonstration (MFD), a Japanese Space Agency-sponsored experiment. Also in Discoverys payload bay are the Technology Applications and Science-1 (TAS-1) and International Extreme Ultraviolet Hitchhiker-2 (IEH-2) experiments.

  6. Use of IRI to Model the Effect of Ionosphere Emission on Earth Remote Sensing at L-Band

    NASA Technical Reports Server (NTRS)

    Abraham, Saji; LeVine, David M.

    2004-01-01

    Microwave remote sensing in the window at 1.413 GHz (L-band) set aside for passive use only is important for monitoring sea surface salinity and soil moisture. These parameters are important for understanding ocean dynamics and energy exchange between the surface and atmosphere, and both NASA and ESA plan to launch satellite sensors to monitor these parameters at L-band (Aquarius, Hydros and SMOS). The ionosphere is an important source of error for passive remote sensing at this frequency. In addition to Faraday rotation, emission from the ionosphere is also a potential source of error at L-band. As an aid for correcting for emission, a regression model is presented that relates ionosphere emission to the integrated electron density (TEC). The goal is to use TEC from sources such as TOPEX, JASON or GPS to obtain estimates of emission over the oceans where the electron density profiles needed to compute emission are not available. In addition, data will also be presented to evaluate the use of the IRI for computing emission over the ocean.

  7. Overview of the NASA Wallops Flight Facility Mobile Range Control System

    NASA Technical Reports Server (NTRS)

    Davis, Rodney A.; Semancik, Susan K.; Smith, Donna C.; Stancil, Robert K.

    1999-01-01

    The NASA GSFC's Wallops Flight Facility (WFF) Mobile Range Control System (MRCS) is based on the functionality of the WFF Range Control Center at Wallops Island, Virginia. The MRCS provides real time instantaneous impact predictions, real time flight performance data, and other critical information needed by mission and range safety personnel in support of range operations at remote launch sites. The MRCS integrates a PC telemetry processing system (TELPro), a PC radar processing system (PCDQS), multiple Silicon Graphics display workstations (IRIS), and communication links within a mobile van for worldwide support of orbital, suborbital, and aircraft missions. This paper describes the MRCS configuration; the TELPro's capability to provide single/dual telemetry tracking and vehicle state data processing; the PCDQS' capability to provide real time positional data and instantaneous impact prediction for up to 8 data sources; and the IRIS' user interface for setup/display options. With portability, PC-based data processing, high resolution graphics, and flexible multiple source support, the MRCS system is proving to be responsive to the ever-changing needs of a variety of increasingly complex missions.

  8. The Ultraviolet Spectrograph (UVS) on Juno

    NASA Astrophysics Data System (ADS)

    Gladstone, G. R.; Persyn, S.; Eterno, J.; Slater, D. C.; Davis, M. W.; Versteeg, M. H.; Persson, K. B.; Siegmund, O. H.; Marquet, B.; Gerard, J.; Grodent, D. C.

    2008-12-01

    Juno, a NASA New Frontiers mission, plans for launch in August 2011, a 5-year cruise (including a flyby of Earth in October 2013 for a gravity boost), and 14 months around Jupiter after arriving in August 2016. The spinning (2 RPM), solar-powered Juno will study Jupiter from a highly elliptical orbit, in which the spacecraft (for about 6 hours once every 11 days) dives down over the north pole, skims the outermost atmosphere, and rises back up over the south pole. This orbit allows Juno avoid most of the intense particle radiation surrounding the planet and provides an excellent platform for investigating Jupiter's polar magnetosphere. Part of the exploration of Jupiter's polar magnetosphere will involve remote sensing of the far-ultraviolet H and H2 auroral emissions, plus gases such as methane and acetylene which add their absorption signature to the H2 emissions. This hydrocarbon absorption can be used to estimate the energy of the precipitating electrons; since more energetic electrons penetrate deeper into the atmosphere and the UV emissions they produce will show more absorption. Juno will carry an Ultraviolet Spectrograph (UVS) to make spectral images of Jupiter's aurora. UVS is a UV imaging spectrograph sensitive to both extreme and far ultraviolet emissions in the 70-205~nm range that will characterize the morphology and spectral nature of Jupiter's auroral emissions. Juno UVS consists of two separate sections: a dedicated telescope/spectrograph assembly and a vault electronics box. The telescope/spectrograph assembly contains a telescope which feeds a 0.15-m Rowland circle spectrograph. The telescope has an input aperture 40×40~mm2 and uses an off-axis parabolic primary mirror. A flat scan mirror situated at the front end of the telescope (used to target specific auroral features at up to ±30° perpendicular to the Juno spin plane) directs incoming light to the primary. The light is then focused onto the spectrograph entrance slit, which has a 'dog- bone' shape 6° long, in three 2° sections of 0.2°, 0.05°, and 0.2° width (projected onto the sky). Light entering the slit is dispersed by a toroidal grating which focuses the UV bandpass onto a curved microchannel plate (MCP) cross delay line (XDL) detector with a solar blind UV- sensitive CsI photocathode, which makes up the instrument's focal plane. Tantalum shielding surrounds the detector assembly to protect the detector and the adjacent detector electronics from high-energy electrons. The main electronics box is located in the Juno vault. Inside are two redundant high-voltage power supplies (HVPS), two redundant low-voltage power supplies, the command and data handling (C&DH) electronics, heater/actuator activation electronics, scan mirror electronics, and event processing electronics. An overview of the UVS design and scientific performance will be presented.

  9. Observation and Modeling of Chromospheric Evaporation in a Coronal Loop Related to Active Region Transient Brightening

    NASA Astrophysics Data System (ADS)

    Gupta, G. R.; Sarkar, Aveek; Tripathi, Durgesh

    2018-04-01

    Using the observations recorded by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory and the Interface Region Imaging Spectrograph (IRIS) and the Extreme-ultraviolet Imaging Spectrometer and X-Ray Telescope both on board Hinode, we present evidence of chromospheric evaporation in a coronal loop after the occurrence of two active region transient brightenings (ARTBs) at the two footpoints. The chromospheric evaporation started nearly simultaneously in all of the three hot channels of AIA 131, 94, and 335 Å and was observed to be temperature dependent, being fastest in the highest temperature channel. The whole loop became fully brightened following the ARTBs after ≈25 s in 131 Å, ≈40 s in 94 Å, and ≈6.5 minutes in 335 Å. The differential emission measurements at the two footpoints (i.e., of two ARTBs) and at the loop top suggest that the plasma attained a maximum temperature of ∼10 MK at all these locations. The spectroscopic observations from IRIS revealed the presence of redshifted emission of ∼20 km s‑1 in cooler lines like C II and Si IV during the ARTBs that was cotemporal with the evaporation flow at the footpoint of the loop. During the ARTBs, the line width of C II and Si IV increased nearly by a factor of two during the peak emission. Moreover, enhancement in the line width preceded that in the Doppler shift, which again preceded enhancement in the intensity. The observed results were qualitatively reproduced by 1D hydrodynamic simulations, where energy was deposited at both of the footpoints of a monolithic coronal loop that mimicked the ARTBs identified in the observations.

  10. NASA's Best-Observed X-Class Flare of All Time

    NASA Image and Video Library

    2014-05-07

    This combined image shows the March 29, 2014, X-class flare as seen through the eyes of different observatories. SDO is on the bottom/left, which helps show the position of the flare on the sun. The darker orange square is IRIS data. The red rectangular inset is from Sacramento Peak. The violet spots show the flare's footpoints from RHESSI. -- On March 29, 2014 the sun released an X-class flare. It was observed by NASA's Interface Region Imaging Spectrograph, or IRIS; NASA's Solar Dynamics Observatory, or SDO; NASA's Reuven Ramaty High Energy Solar Spectroscopic Imager, or RHESSI; the Japanese Aerospace Exploration Agency's Hinode; and the National Solar Observatory's Dunn Solar Telescope located at Sacramento Peak in New Mexico. To have a record of such an intense flare from so many observatories is unprecedented. Such research can help scientists better understand what catalyst sets off these large explosions on the sun. Perhaps we may even some day be able to predict their onset and forewarn of the radio blackouts solar flares can cause near Earth - blackouts that can interfere with airplane, ship and military communications. Read more: 1.usa.gov/1kMDQbO Join our Google+ Hangout on May 8 at 2:30pm EST: go.nasa.gov/1mwbBEZ Credit: NASA Goddard 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

  11. ANALYSIS OF CORONAL RAIN OBSERVED BY IRIS , HINODE /SOT, AND SDO /AIA: TRANSVERSE OSCILLATIONS, KINEMATICS, AND THERMAL EVOLUTION

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

    Kohutova, P.; Verwichte, E., E-mail: p.kohutova@warwick.ac.uk

    Coronal rain composed of cool plasma condensations falling from coronal heights along magnetic field lines is a phenomenon occurring mainly in active region coronal loops. Recent high-resolution observations have shown that coronal rain is much more common than previously thought, suggesting its important role in the chromosphere-corona mass cycle. We present the analysis of MHD oscillations and kinematics of the coronal rain observed in chromospheric and transition region lines by the Interface Region Imaging Spectrograph (IRIS) , the Hinode Solar Optical Telescope (SOT), and the Solar Dynamics Observatory ( SDO) Atmospheric Imaging Assembly (AIA). Two different regimes of transverse oscillationsmore » traced by the rain are detected: small-scale persistent oscillations driven by a continuously operating process and localized large-scale oscillations excited by a transient mechanism. The plasma condensations are found to move with speeds ranging from few km s{sup −1} up to 180 km s{sup −1} and with accelerations largely below the free-fall rate, likely explained by pressure effects and the ponderomotive force resulting from the loop oscillations. The observed evolution of the emission in individual SDO /AIA bandpasses is found to exhibit clear signatures of a gradual cooling of the plasma at the loop top. We determine the temperature evolution of the coronal loop plasma using regularized inversion to recover the differential emission measure (DEM) and by forward modeling the emission intensities in the SDO /AIA bandpasses using a two-component synthetic DEM model. The inferred evolution of the temperature and density of the plasma near the apex is consistent with the limit cycle model and suggests the loop is going through a sequence of periodically repeating heating-condensation cycles.« less

  12. WHAT IS THE SOURCE OF QUIET SUN TRANSITION REGION EMISSION?

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

    Schmit, D. J.; De Pontieu, Bart

    Dating back to the first observations of the on-disk corona, there has been a qualitative link between the photosphere’s magnetic network and enhanced transition-temperature plasma emission. These observations led to the development of a general model that describes emission structures through the partitioning of the atmospheric volume with different magnetic loop geometries that exhibit different energetic equilibria. Does the internetwork produce transition-temperature emission? What fraction of network flux connects to the corona? How does quiet Sun emission compare with low-activity Sun-like stars? In this work, we revisit the canonical model of the quiet Sun, with high-resolution observations from the Interfacemore » Region Imaging Spectrograph ( IRIS ) and HMI in hand, to address those questions. We use over 900 deep exposures of Si iv 1393 Å from IRIS along with nearly simultaneous HMI magnetograms to quantify the correlation between transition-temperature emission structures and magnetic field concentrations through a number of novel statistics. Our observational results are coupled with analysis of the Bifrost MHD model and a large-scale potential field model. Our results paint a complex portrait of the quiet Sun. We measure an emission signature in the distant internetwork that cannot be attributed to network contribution. We find that the dimmest regions of emission are not linked to the local vertical magnetic field. Using the MHD simulation, we categorize the emission contribution from cool mid-altitude loops and high-altitude coronal loops and discuss the potential emission contribution of spicules. Our results provide new constraints on the coupled solar atmosphere so that we can build on our understanding of how dynamic thermal and magnetic structures generate the observed phenomena in the transition region.« less

  13. Blue-wing enhancement of the chromospheric Mg II h and k lines in a solar flare

    NASA Astrophysics Data System (ADS)

    Tei, Akiko; Sakaue, Takahito; Okamoto, Takenori J.; Kawate, Tomoko; Heinzel, Petr; UeNo, Satoru; Asai, Ayumi; Ichimoto, Kiyoshi; Shibata, Kazunari

    2018-05-01

    We performed coordinated observations of AR 12205, which showed a C-class flare on 2014 November 11, with the Interface Region Imaging Spectrograph (IRIS) and the Domeless Solar Telescope (DST) at Hida Observatory. Using spectral data in the Si IV 1403 Å, C II 1335 Å, and Mg II h and k lines from IRIS and the Ca II K, Ca II 8542 Å, and Hα lines from DST, we investigated a moving flare kernel during the flare. In the Mg II h line, the leading edge of the flare kernel showed an intensity enhancement in the blue wing and a smaller intensity of the blue-side peak (h2v) than that of the red-side one (h2r). The blueshift lasted for 9-48 s with a typical speed of 10.1 ± 2.6 km s-1, which was followed by a high intensity and a large redshift with a speed of up to 51 km s-1 detected in the Mg II h line. The large redshift was a common property for all six lines, but the blueshift prior to it was found only in the Mg II lines. Cloud modeling of the Mg II h line suggests that the blue-wing enhancement with such a peak difference could have been caused by a chromospheric-temperature (cool) upflow. We discuss a scenario in which an upflow of cool plasma is lifted up by expanding hot plasma owing to the deep penetration of non-thermal electrons into the chromosphere. Furthermore, we found that the blueshift persisted without any subsequent redshift in the leading edge of the flare kernel during its decaying phase. The cause of such a long-lasting blueshift is also discussed.

  14. A green observatory in the Chilean Atacama desert

    NASA Astrophysics Data System (ADS)

    Ramolla, Michael; Westhues, Christian; Hackstein, Moritz; Haas, Martin; Hodapp, Klaus; Lemke, Roland; Barr Domínguez, Angie; Chini, Rolf; Murphy, Miguel

    2016-08-01

    Since 2007, the Ruhr-Universität Bochum (RUB) in Germany and Universidad Católica del Norte (UCN) in Chile jointly operate the Universitätssternwarte der Ruhr-Universität Bochum (USB), which is located in direct neighborhood of the future E-ELT of ESO. It is the only observatory powered exclusively by solar panels and wind turbines. Excess power is stored in batteries that allow uninterrupted operation even in windless nights. The scientific equipment consists of three robotic optical telescopes with apertures ranging from 15 cm (RoBoTT) over 25 cm (BESTII) to 40 cm (BMT) and one 80 cm (IRIS) infra-red telescope. The optical telescopes are equipped with Johnson and Sloan broad band filters together with a large number of narrow and intermediate bands. In the infrared, J,H and K filters are available, accompanied by several narrow bands near the K band wavelength. The second Nasmyth focus in the 80 cm telescope feeds a high resolution echelle spectrograph similar to the FEROS instrument of ESO. This variety of instruments has evolved from different collaborations, i.e. with the University of Hawaii (IfA) in the USA, which provided the near-infrared-camera of the IRIS telescope, or with the Deutsches Zentrum für Luft- und Raumfahrt (DLR) in Germany, which provided the BESTII telescope. The highly automatized processes on all telescopes enable a single person to run the whole facility, providing the high cost efficiency required for an university observatory. The excellent site conditions allow projects that require daily observations of astronomical objects over epochs of several months or years. Here we report on such studies of young stellar objects from the Bochum Galactic Disk Survey, the multiplicity of stars, quasar variability or the hunt for exo-planets.

  15. Structure of sunspot light bridges in the chromosphere and transition region

    NASA Astrophysics Data System (ADS)

    Rezaei, R.

    2018-01-01

    Context. Light bridges (LBs) are elongated structures with enhanced intensity embedded in sunspot umbra and pores. Aims: We studied the properties of a sample of 60 LBs observed with the Interface Region Imaging Spectrograph (IRIS). Methods: Using IRIS near- and far-ultraviolet spectra, we measured the line intensity, width, and Doppler shift; followed traces of LBs in the chromosphere and transition region (TR); and compared LB parameters with umbra and quiet Sun. Results: There is a systematic emission enhancement in LBs compared to nearby umbra from the photosphere up to the TR. Light bridges are systematically displaced toward the solar limb at higher layers: the amount of the displacement at one solar radius compares well with the typical height of the chromosphere and TR. The intensity of the LB sample compared to the umbra sample peaks at the middle/upper chromosphere where they are almost permanently bright. Spectral lines emerging from the LBs are broader than the nearby umbra. The systematic redshift of the Si IV line in the LB sample is reduced compared to the quiet Sun sample. We found a significant correlation between the line width of ions arising at temperatures from 3 × 104 to 1.5 × 105 K as there is also a strong spatial correlation among the line and continuum intensities. In addition, the intensity-line width relation holds for all spectral lines in this study. The correlations indicate that the cool and hot plasma in LBs are coupled. Conclusions: Light bridges comprise multi-temperature and multi-disciplinary structures extending up to the TR. Diverse heating sources supply the energy and momentum to different layers, resulting in distinct dynamics in the photosphere, chromosphere, and TR.

  16. Performance of The Far Ultraviolet Spectroscopic Explorer Mirror Assemblies

    NASA Technical Reports Server (NTRS)

    Ohi, Raymond G.; Barkhouser, Robert H.; Conard, Steven J.; Friedman, Scott D.; Hampton, Jeffery; Moos, H. Warren; Nikulla, Paul; Oliveira, Cristina M.; Saha, Timo T.; Obenschain, Arthur (Technical Monitor)

    2000-01-01

    The Far Ultraviolet Spectroscopic Explorer is a NASA astrophysics satellite which produces high-resolution spectra in the far-ultraviolet (90.5-118.7 nm bandpass) using a high effective area and low background detectors. The observatory was launched on its three-year mission from Cape Canaveral Air Station on 24 June 1999. The instrument contains four coaligned, normal incidence, off-axis parabolic mirrors which illuminate separate Rowland circle spectrograph channels equipped with holographically ruled diffraction gratings and delay line microchannel plate detectors. The telescope mirrors have a 352 x 387 mm aperture and 2245 mm focal length and are attached to actuator assemblies, which provide on-orbit, tip, tilt, and focus control. Two mirrors are coated with silicon carbide (SiC) and two are coated with lithium fluoride over aluminum (Al:LiF). We describe mirror assembly in-flight optical and mechanical performance. On-orbit measurements of the far-ultraviolet point spread function associated with each mirror are compared to expectations based on pre-flight laboratory measurements and modeling using the Optical Surface Analysis Code and surface metrology data. On-orbit imaging data indicate that the mirrors meet their instrument-level requirement of 50 percent and 95 percent slit transmission for the high- and mid-resolution spectrograph entrance slits, respectively. The degradation of mirror reflectivity during satellite integration and test is also discussed. The far-ultraviolet reflectivity of the SiC- and AlLiF-coated mirrors decreased about six percent and three percent, respectively, between coating and launch. Each mirror is equipped with three actuators, which consist of a stepper motor driving a ball screw via a two-stage planetary gear train. We also discuss the mechanical performance of the mirror assemblies, including actuator performance and thermal effects.

  17. Performance of the Far Ultraviolet Spectroscopic Explorer mirror assemblies

    NASA Astrophysics Data System (ADS)

    Ohl, Raymond G.; Barkhouser, Robert H.; Conard, Steven J.; Friedman, Scott D.; Hampton, Jeffrey; Moos, H. Warren; Nikulla, Paul; Oliveira, Cristina M.; Saha, Timo T.

    2000-12-01

    The Far Ultraviolet Spectroscopic Explorer is a NASA astrophysics satellite which produces high-resolution spectra in the far-ultraviolet (90.5 - 118.7 nm bandpass) using a high effective area and low background detectors. The observatory was launched on its three-year mission from Cape Canaveral Air Station on 24 June 1999. The instrument contains four co- aligned, normal incidence, off-axis parabolic mirrors which illuminate separate Rowland circle spectrograph channels equipped with holographically ruled diffraction gratings and delay line microchannel plate detectors. The telescope mirrors have a 352 X 387 mm aperture and 2245 mm focal length and are attached to actuator assemblies, which provide on-orbit, tip, tilt, and focus control. Two mirrors are coated with silicon carbide (SiC) and two are coated with lithium fluoride over aluminum (Al:LiF). We describe mirror assembly in-flight optical and mechanical performance. On-orbit measurements of the far-ultraviolet point spread function associated with each mirror are compared to expectations based on pre-flight laboratory measurements and modeling using the Optical Surface Analysis Code and surface metrology data. On-orbit imaging data indicate that the mirrors meet their instrument-level requirement of 50% and 95% slit transmission for the high- and mid-resolution spectrograph entrance slits, respectively. The degradation of mirror reflectivity during satellite integration and test is also discussed. The FUV reflectivity of the SiC- and Al:LiF-coated mirrors decreased about 6% and 3%, respectively, between coating and launch. Each mirror is equipped with three actuators, which consist of a stepper motor driving a ball screw via a two-stage planetary gear train. We also discuss the mechanical performance of the mirror assemblies, including actuator performance and thermal effects.

  18. UNDERFLIGHT CALIBRATION OF SOHO/CDS AND HINODE/EIS WITH EUNIS-07

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

    Wang Tongjiang; Brosius, Jeffrey W.; Thomas, Roger J.

    2011-12-01

    Flights of Goddard Space Flight Center's Extreme Ultraviolet Normal Incidence Spectrograph (EUNIS) sounding rocket in 2006 and 2007 provided updated radiometric calibrations for Solar and Heliospheric Observatory/Coronal Diagnostic Spectrometer (SOHO/CDS) and Hinode/Extreme Ultraviolet Imaging Spectrometer (Hinode/EIS). EUNIS carried two independent imaging spectrographs covering wavebands of 300-370 A in first order and 170-205 A in second order. After each flight, end-to-end radiometric calibrations of the rocket payload were carried out in the same facility used for pre-launch calibrations of CDS and EIS. During the 2007 flight, EUNIS, SOHO/CDS, and Hinode/EIS observed the same solar locations, allowing the EUNIS calibrations to bemore » directly applied to both CDS and EIS. The measured CDS NIS 1 line intensities calibrated with the standard (version 4) responsivities with the standard long-term corrections are found to be too low by a factor of 1.5 due to the decrease in responsivity. The EIS calibration update is performed in two ways. One uses the direct calibration transfer of the calibrated EUNIS-07 short wavelength (SW) channel. The other uses the insensitive line pairs, in which one member was observed by the EUNIS-07 long wavelength (LW) channel and the other by EIS in either the LW or SW waveband. Measurements from both methods are in good agreement, and confirm (within the measurement uncertainties) the EIS responsivity measured directly before the instrument's launch. The measurements also suggest that the EIS responsivity decreased by a factor of about 1.2 after the first year of operation (although the size of the measurement uncertainties is comparable to this decrease). The shape of the EIS SW response curve obtained by EUNIS-07 is consistent with the one measured in laboratory prior to launch. The absolute value of the quiet-Sun He II 304 A intensity measured by EUNIS-07 is consistent with the radiance measured by CDS NIS in quiet regions near the disk center and the solar minimum irradiance recently obtained by CDS NIS and the Solar Dynamics Observatory/Extreme Ultraviolet Variability Experiment.« less

  19. Longitudinal Ionospheric Variability Observed by LITES on the ISS

    NASA Astrophysics Data System (ADS)

    Stephan, A. W.; Finn, S. C.; Cook, T.; Geddes, G.; Chakrabarti, S.; Budzien, S. A.

    2017-12-01

    The Limb-Imaging Ionospheric and Thermospheric Extreme-Ultraviolet Spectrograph (LITES) is an imaging spectrograph designed to measure altitude profiles (150-350 km) of extreme- and far-ultraviolet airglow emissions that originate from photochemical processes in the ionosphere and thermosphere. During the daytime, LITES observes the bright O+ 83.4 nm emission from which the ionospheric profile can be inferred. At night, recombination emissions at 91.1 and 135.6 nm provide a direct measure of the electron content along the line of sight. LITES was launched and installed on the International Space Station (ISS) in late February 2017 where it has been operating along with the highly complementary GPS Radio Occultation and Ultraviolet Photometry - Colocated (GROUP-C) experiment. We will present some of the first observations from LITES in April 2017 that show longitudinal patterns in ionospheric density and the daily variability in those patterns. LITES vertical imaging from a vantage point near 410 km enables a particularly unique perspective on the altitude of the ionospheric peak density at night that can complement and inform other ground- and space-based measurements, and track the longitude-altitude variability that is reflective of changes in equatorial electrodynamics.

  20. High-Resolution Spectroscopy at the Wyoming Infrared Observatory: Setting TESS Science on FHiRE

    NASA Astrophysics Data System (ADS)

    Jang-Condell, Hannah; Pierce, Michael J.; Pilachowski, C. A.; Kobulnicky, Henry; McLane, Jacob N.

    2018-01-01

    The Fiber High Resolution Echelle (FHiRE) spectrograph is a new instrument designed for the 2.3-m Wyoming InfraRed Observatory (WIRO). With the construction of a vacuum chamber for FHiRE to stabilize the spectrograph and a temperature-stabilized Thorium-Argon lamp for precise velocity calibration, we will be able to achieve 1 m/s RV precision, making it an ideal instrument for finding exoplanets. Details of the design of FHiRE are presented in a companion poster (Pierce et al.). The construction of this instrument is well-timed with the planned 2018 launch of NASA's Transiting Exoplanet Survey Satellite (TESS) mission. TESS will require a great deal of follow-up spectroscopy to characterize potential exoplanet host stars as well as radial velocity measurements to confirm new exoplanets. WIRO is ideally suited to acquire the long-term, high-cadence observations that will be required to make progress in this frontier area of astrophysics. We will coordinate our efforts with the TESS Follow-up Observing Program (TFOP), specifically as part of the Recon Spectroscopy and Precise Radial Velocity Work sub-groups.This work is supported by a grant from NASA EPSCOR.

  1. FAQs about IRIs.

    ERIC Educational Resources Information Center

    Paris, Scott G.; Carpenter, Robert D.

    2003-01-01

    Provides information about informal reading inventories (IRI), an early reading assessment. Explains what IRIs are; who should administer an IRI; when and how to administer an IRI; the reliability of data from IRIs; and the limitations of IRIs. (PM)

  2. Midcourse Space Experiment Data Certification and Technology Transfer

    NASA Technical Reports Server (NTRS)

    Pollock, David B.

    1997-01-01

    The University of Alabama in Huntsville contributes to the Technical Management of the Midcourse Space Experiment Program, to the Certification of the Level 2 data produced by the Midcourse Space Experiment's suite of in-orbit imaging radiometers, imaging spectra-radiometers and an interferometer and to the Transfer of the Midcourse Space Experiment Technology to other Government Programs. The Technical Management of the Midcourse Space Experiment Program is expected to continue through out the spacecraft's useful life time, 5 years after its 1996 launch. The Transfer of Midcourse Space Experiment Technology to other government elements is expected to be on a demand basis by the United States Government and other organizations. The University of Alabama Huntsville' contribution specifically supports the nine Ultraviolet Visible Imagers and Spectrographic Imagers (UVISI) and the Pointing and Alignment of all eleven of the science instruments. The science instruments effectively cover the 0.1 to 28 micron spectral region. The Midcourse Space Experiment spacecraft, launched April 24, 1996, is expected to have a 5 year useful lifetime with a 12 month lifetime for the cryogenically cooled IR sensor. A pre-launch, ground based calibration of the instruments provided a basis for the pre-launch certification of the Level 2 data base these instruments produce. With the spacecraft in-orbit the certification of the instruments' Level 2 data base is being extended to the in-orbit environment.

  3. KSC-2009-3087

    NASA Image and Video Library

    2009-05-11

    CAPE CANAVERAL, Fla. – On Launch Pad 39A at NASA's Kennedy Space Center in Florida, space shuttle Atlantis rises past the fixed service structure as it races toward space on the STS-125 mission. Atlantis will rendezvous with NASA's Hubble Space Telescope on the STS-125 mission. Liftoff was on time at 2:01 p.m. EDT. Atlantis' 11-day flight will include five spacewalks to refurbish and upgrade the telescope with state-of-the-art science instruments that will expand Hubble's capabilities and extend its operational lifespan through at least 2014. The payload includes a Wide Field Camera 3, fine guidance sensor and the Cosmic Origins Spectrograph. Photo credit: NASA/Michael Gayle-Rusty Backer

  4. On-Orbit Sky Background Measurements with the FOS

    NASA Technical Reports Server (NTRS)

    Lyons, R. W.; Baity, W. A.; Beaver, E. A.; Cohen, R. D.; Junkkarinen, V. T.; Linsky, J. B.; Bohlin, R. C.

    1993-01-01

    Observations of the sky background obtained with the Faint Object Spectrograph during 1991-1992 are discussed. Sky light can be an important contributor to the observed count rate in several of the instrument configurations especially when large apertures are used. In general, the sky background is consistent with the pre-launch expectations and showed the expected effects of zodiacal light and diffuse galactic light. In addition to these sources, there is, particularly during the daytime, a highly variable airglow component which includes a number of emission lines. The sky background will have an impact on the reduction and possibly the interpretation of some spectra.

  5. The Ultraviolet Total Ozone Unit (TOU) IN-ORBIT PERFORMANCE AND CALIBRATION

    NASA Astrophysics Data System (ADS)

    Wang, Yongmei; Fu, Liping; Zhang, Zhongmou

    The Ultraviolet Total Ozone Unit (TOU) was launched on 27 May 2008 on FY-3 meteorological satellite. The main purpose of TOU is to measure the incident solar radiation and backscattered ultraviolet radiance for retrieving daily global map of atmospheric ozone. TOU is a fixed grating and slit-array Ebert-Fastie grating spectrograph system. It has the multi-wavelengths detecting and two-dimensional scanning which enables global daily ground coverage. This paper discusses the recent working status of the instrument, including the sensitivity, measuring precision of solar irradiance, diffuser degradation and wavelength drift, and then presents the in-flight calibration and performance results.

  6. Correspondence between solar fine-scale structures in the corona, transition region, and lower atmosphere from collaborative observations

    NASA Technical Reports Server (NTRS)

    Moses, J. Daniel; Cook, J. W.; Bartoe, J.-D. F.; Brueckner, G. E.; Dere, K. P.; Webb, D. F.; Davis, John M.; Recely, F.; Martin, S. F.; Zirin, H.

    1989-01-01

    The Soft X-Ray Imaging Payload and the High Resolution Telescope and Spectrograph (HRTS) instrument were launched from White Sands on 11 December 1987 in coordinated sounding rocket flights to investigate the correspondence of coronal and transition region structures, especially the relationship between X-ray bright points (XBPs) and transition region small spatial scale energetic events. The coaligned data from X-ray images are presented along with maps of sites of transition region energetic events observed in C IV (100,000 K), HRTS 1600 A spectroheliograms of the T sub min region and ground based magnetogram and He I 10830 A images.

  7. Iris Image Classification Based on Hierarchical Visual Codebook.

    PubMed

    Zhenan Sun; Hui Zhang; Tieniu Tan; Jianyu Wang

    2014-06-01

    Iris recognition as a reliable method for personal identification has been well-studied with the objective to assign the class label of each iris image to a unique subject. In contrast, iris image classification aims to classify an iris image to an application specific category, e.g., iris liveness detection (classification of genuine and fake iris images), race classification (e.g., classification of iris images of Asian and non-Asian subjects), coarse-to-fine iris identification (classification of all iris images in the central database into multiple categories). This paper proposes a general framework for iris image classification based on texture analysis. A novel texture pattern representation method called Hierarchical Visual Codebook (HVC) is proposed to encode the texture primitives of iris images. The proposed HVC method is an integration of two existing Bag-of-Words models, namely Vocabulary Tree (VT), and Locality-constrained Linear Coding (LLC). The HVC adopts a coarse-to-fine visual coding strategy and takes advantages of both VT and LLC for accurate and sparse representation of iris texture. Extensive experimental results demonstrate that the proposed iris image classification method achieves state-of-the-art performance for iris liveness detection, race classification, and coarse-to-fine iris identification. A comprehensive fake iris image database simulating four types of iris spoof attacks is developed as the benchmark for research of iris liveness detection.

  8. Wilber 3: A Python-Django Web Application For Acquiring Large-scale Event-oriented Seismic Data

    NASA Astrophysics Data System (ADS)

    Newman, R. L.; Clark, A.; Trabant, C. M.; Karstens, R.; Hutko, A. R.; Casey, R. E.; Ahern, T. K.

    2013-12-01

    Since 2001, the IRIS Data Management Center (DMC) WILBER II system has provided a convenient web-based interface for locating seismic data related to a particular event, and requesting a subset of that data for download. Since its launch, both the scale of available data and the technology of web-based applications have developed significantly. Wilber 3 is a ground-up redesign that leverages a number of public and open-source projects to provide an event-oriented data request interface with a high level of interactivity and scalability for multiple data types. Wilber 3 uses the IRIS/Federation of Digital Seismic Networks (FDSN) web services for event data, metadata, and time-series data. Combining a carefully optimized Google Map with the highly scalable SlickGrid data API, the Wilber 3 client-side interface can load tens of thousands of events or networks/stations in a single request, and provide instantly responsive browsing, sorting, and filtering of event and meta data in the web browser, without further reliance on the data service. The server-side of Wilber 3 is a Python-Django application, one of over a dozen developed in the last year at IRIS, whose common framework, components, and administrative overhead represent a massive savings in developer resources. Requests for assembled datasets, which may include thousands of data channels and gigabytes of data, are queued and executed using the Celery distributed Python task scheduler, giving Wilber 3 the ability to operate in parallel across a large number of nodes.

  9. Bridging the Gap: Capturing the Lyα Counterpart of a Type-II Spicule and Its Heating Evolution with VAULT2.0 and IRIS Observations

    NASA Astrophysics Data System (ADS)

    Chintzoglou, Georgios; De Pontieu, Bart; Martínez-Sykora, Juan; Pereira, Tiago M. D.; Vourlidas, Angelos; Tun Beltran, Samuel

    2018-04-01

    We present results from an observing campaign in support of the VAULT2.0 sounding rocket launch on 2014 September 30. VAULT2.0 is a Lyα (1216 Å) spectroheliograph capable of providing spectroheliograms at high cadence. Lyα observations are highly complementary to the IRIS observations of the upper chromosphere and the low transition region (TR) but have previously been unavailable. The VAULT2.0 data provide new constraints on upper-chromospheric conditions for numerical models. The observing campaign was closely coordinated with the IRIS mission. Taking advantage of this simultaneous multi-wavelength coverage of target AR 12172 and by using state-of-the-art radiative-MHD simulations of spicules, we investigate in detail a type-II spicule associated with a fast (300 km s‑1) network jet recorded in the campaign observations. Our analysis suggests that spicular material exists suspended high in the atmosphere but at lower temperatures (seen in Lyα) until it is heated and becomes visible in TR temperatures as a network jet. The heating begins lower in the spicule and propagates upwards as a rapidly propagating thermal front. The front is then observed as fast, plane-of-the-sky motion typical of a network jet, but contained inside the pre-existing spicule. This work supports the idea that the high speeds reported in network jets should not be taken as real mass upflows but only as apparent speeds of a rapidly propagating heating front along the pre-existing spicule.

  10. Integration, commissioning, and performance of the UK FMOS spectrograph

    NASA Astrophysics Data System (ADS)

    Dalton, Gavin B.; Lewis, Ian J.; Tosh, Ian A. J.; Blackburn, Colin; Bonfield, David G.; Brooks, Charles B.; Holmes, Alan R.; Lee, Hanshin; Froud, Tim R.; Akiyama, Masayuki; Tamura, Naoyuki; Takato, Naruhisa

    2008-07-01

    The UK FMOS spectrograph forms part of Subaru's FMOS multi-object infrared spectroscopy facility. The spectrograph was shipped to Hilo in component form in August of 2007. We describe the integration sequence for the spectrograph, the results of cooldown tests using a new chiller unit fitted to the spectrograph at the telescope, and alignment tests of the spectrograph, gratings and OH-suppression masks. We present the first-light observations for the spectrograph from May 2008.

  11. Iris Matching Based on Personalized Weight Map.

    PubMed

    Dong, Wenbo; Sun, Zhenan; Tan, Tieniu

    2011-09-01

    Iris recognition typically involves three steps, namely, iris image preprocessing, feature extraction, and feature matching. The first two steps of iris recognition have been well studied, but the last step is less addressed. Each human iris has its unique visual pattern and local image features also vary from region to region, which leads to significant differences in robustness and distinctiveness among the feature codes derived from different iris regions. However, most state-of-the-art iris recognition methods use a uniform matching strategy, where features extracted from different regions of the same person or the same region for different individuals are considered to be equally important. This paper proposes a personalized iris matching strategy using a class-specific weight map learned from the training images of the same iris class. The weight map can be updated online during the iris recognition procedure when the successfully recognized iris images are regarded as the new training data. The weight map reflects the robustness of an encoding algorithm on different iris regions by assigning an appropriate weight to each feature code for iris matching. Such a weight map trained by sufficient iris templates is convergent and robust against various noise. Extensive and comprehensive experiments demonstrate that the proposed personalized iris matching strategy achieves much better iris recognition performance than uniform strategies, especially for poor quality iris images.

  12. Near Earth Network (NEN) CubeSat Communications

    NASA Technical Reports Server (NTRS)

    Schaire, Scott

    2017-01-01

    The NASA Near Earth Network (NEN) consists of globally distributed tracking stations, including NASA, commercial, and partner ground stations, that are strategically located to maximize the coverage provided to a variety of orbital and suborbital missions, including those in LEO (Low Earth Orbit), GEO (Geosynchronous Earth Orbit), HEO (Highly Elliptical Orbit), lunar and L1-L2 orbits. The NEN's future mission set includes and will continue to include CubeSat missions. The first NEN-supported CubeSat mission will be the Cubesat Proximity Operations Demonstration (CPOD) launching into LEO in 2017. The majority of the CubeSat missions destined to fly on EM-1, launching in late 2018, many in a lunar orbit, will communicate with ground-based stations via X-band and will utilize the NASA Jet Propulsion Laboratory (JPL)-developed IRIS (Satellite Communication for Air Traffic Management) radio. The NEN recognizes the important role CubeSats are beginning to play in carrying out NASAs mission and is therefore investigating the modifications needed to provide IRIS radio compatibility. With modification, the NEN could potentially expand support to the EM-1 (Exploration Mission-1) lunar CubeSats. The NEN could begin providing significant coverage to lunar CubeSat missions utilizing three to four of the NEN's mid-latitude sites. This coverage would supplement coverage provided by the JPL Deep Space Network (DSN). The NEN, with smaller apertures than DSN, provides the benefit of a larger beamwidth that could be beneficial in the event of uncertain ephemeris data. In order to realize these benefits the NEN would need to upgrade stations targeted based on coverage ability and current configuration ease of upgrade, to ensure compatibility with the IRIS radio. In addition, the NEN is working with CubeSat radio developers to ensure NEN compatibility with alternative CubeSat radios for Lunar and L1-L2 CubeSats. The NEN has provided NEN compatibility requirements to several radio developers who are developing radios that offer lower cost and, in some cases, more capabilities with fewer constraints. The NEN is ready to begin supporting CubeSat missions. The NEN is considering network upgrades to broaden the types of CubeSat missions that can be supported and is supporting both the CubeSat community and radio developers to ensure future CubeSat missions have multiple options when choosing a network for their communications support.

  13. NASA Near Earth Network (NEN) Support for Lunar and L1/L2 CubeSats

    NASA Technical Reports Server (NTRS)

    Schaire, Scott H.

    2017-01-01

    The NASA Near Earth Network (NEN) consists of globally distributed tracking stations, including NASA, commercial, and partner ground stations, that are strategically located to maximize the coverage provided to a variety of orbital and suborbital missions, including those in LEO, GEO, HEO, lunar and L1/L2 orbits. The NENs future mission set includes and will continue to include CubeSat missions. The first NEN supported CubeSat mission will be the Cubesat Proximity Operations Demonstration (CPOD) launching into low earth orbit (LEO) in early 2017. The majority of the CubeSat missions destined to fly on EM-1, launching in late 2018, many in a lunar orbit, will communicate with ground based stations via X-band and will utilize the NASA Jet Propulsion Laboratory (JPL) developed IRIS radio. The NEN recognizes the important role CubeSats are beginning to play in carrying out NASAs mission and is therefore investigating the modifications needed to provide IRIS radio compatibility. With modification, the NEN could potentially expand support to the EM-1 lunar CubeSats. The NEN could begin providing significant coverage to lunar CubeSat missions utilizing three to four of the NENs mid-latitude sites. This coverage would supplement coverage provided by the JPL Deep Space Network (DSN). The NEN, with smaller apertures than DSN, provides the benefit of a larger beamwidth that could be beneficial in the event of uncertain ephemeris data. In order to realize these benefits the NEN would need to upgrade stations targeted based on coverage ability and current configurationease of upgrade, to ensure compatibility with the IRIS radio.In addition, the NEN is working with CubeSat radio developers to ensure NEN compatibility with alternative CubeSat radios for Lunar and L1/L2 CubeSats. The NEN has provided NEN compatibility requirements to several radio developers who are developing radios that offer lower cost and, in some cases, more capabilities with fewer constraints. The NEN is ready to begin supporting CubeSat missions. The NEN is considering network upgrades to broaden the types of CubeSat missions that can be supported and is supporting both the CubeSat community and radio developers to ensure future CubeSat missions have multiple options when choosing a network for their communications support.

  14. Antigen-Specific Interferon-Gamma Responses and Innate Cytokine Balance in TB-IRIS

    PubMed Central

    Goovaerts, Odin; Jennes, Wim; Massinga-Loembé, Marguerite; Ceulemans, Ann; Worodria, William; Mayanja-Kizza, Harriet; Colebunders, Robert; Kestens, Luc

    2014-01-01

    Background Tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) remains a poorly understood complication in HIV-TB patients receiving antiretroviral therapy (ART). TB-IRIS could be associated with an exaggerated immune response to TB-antigens. We compared the recovery of IFNγ responses to recall and TB-antigens and explored in vitro innate cytokine production in TB-IRIS patients. Methods In a prospective cohort study of HIV-TB co-infected patients treated for TB before ART initiation, we compared 18 patients who developed TB-IRIS with 18 non-IRIS controls matched for age, sex and CD4 count. We analyzed IFNγ ELISpot responses to CMV, influenza, TB and LPS before ART and during TB-IRIS. CMV and LPS stimulated ELISpot supernatants were subsequently evaluated for production of IL-12p70, IL-6, TNFα and IL-10 by Luminex. Results Before ART, all responses were similar between TB-IRIS patients and non-IRIS controls. During TB-IRIS, IFNγ responses to TB and influenza antigens were comparable between TB-IRIS patients and non-IRIS controls, but responses to CMV and LPS remained significantly lower in TB-IRIS patients. Production of innate cytokines was similar between TB-IRIS patients and non-IRIS controls. However, upon LPS stimulation, IL-6/IL-10 and TNFα/IL-10 ratios were increased in TB-IRIS patients compared to non-IRIS controls. Conclusion TB-IRIS patients did not display excessive IFNγ responses to TB-antigens. In contrast, the reconstitution of CMV and LPS responses was delayed in the TB-IRIS group. For LPS, this was linked with a pro-inflammatory shift in the innate cytokine balance. These data are in support of a prominent role of the innate immune system in TB-IRIS. PMID:25415590

  15. Subarcsecond bright points and quasi-periodic upflows below a quiescent filament observed by IRIS

    NASA Astrophysics Data System (ADS)

    Li, T.; Zhang, J.

    2016-05-01

    Context. The new Interface Region Imaging Spectrograph (IRIS) mission provides high-resolution observations of UV spectra and slit-jaw images (SJIs). These data have become available for investigating the dynamic features in the transition region (TR) below the on-disk filaments. Aims: The driver of "counter-streaming" flows along the filament spine is still unknown yet. The magnetic structures and the upflows at the footpoints of the filaments and their relations with the filament mainbody have not been well understood. We study the dynamic evolution at the footpoints of filaments in order to find some clues for solving these questions. Methods: Using UV spectra and SJIs from the IRIS, along with coronal images and magnetograms from the Solar Dynamics Observatory (SDO), we present the new features in a quiescent filament channel: subarcsecond bright points (BPs) and quasi-periodic upflows. Results: The BPs in the TR have a spatial scale of about 350-580 km and lifetimes of more than several tens of minutes. They are located at stronger magnetic structures in the filament channel with a magnetic flux of about 1017-1018 Mx. Quasi-periodic brightenings and upflows are observed in the BPs, and the period is about 4-5 min. The BP and the associated jet-like upflow comprise a "tadpole-shaped" structure. The upflows move along bright filament threads, and their directions are almost parallel to the spine of the filament. The upflows initiated from the BPs with opposite polarity magnetic fields have opposite directions. The velocity of the upflows in the plane of sky is about 5-50 km s-1. The emission line of Si IV 1402.77 Å at the locations of upflows exhibits obvious blueshifts of about 5-30 km s-1, and the line profile is broadened with the width of more than 20 km s-1. Conclusions: The BPs seem to be the bases of filament threads, and the upflows are able to convey mass for the dynamic balance of the filament. The "counter-streaming" flows in previous observations may be caused by the propagation of bi-directional upflows initiated from opposite polarity magnetic fields. We suggest that quasi-periodic brightenings of BPs and quasi-periodic upflows result from small-scale oscillatory magnetic reconnections, which are modulated by solar p-mode waves.

  16. Iris reconstruction combined with iris-claw intraocular lens implantation for the management of iris-lens injured patients.

    PubMed

    Hu, Shufang; Wang, Mingling; Xiao, Tianlin; Zhao, Zhenquan

    2016-03-01

    To study the efficiency and safety of iris reconstruction combined with iris-claw intraocular lens (IOL) implantation in the patients with iris-lens injuries. Retrospective, noncomparable consecutive case series study. Eleven patients (11 eyes) following iris-lens injuries underwent iris reconstructions combined with iris-claw IOL implantations. Clinical data, such as cause and time of injury, visual acuity (VA), iris and lens injuries, surgical intervention, follow-up period, corneal endothelial cell count, and optical coherence tomography, were collected. Uncorrected VA (UCVA) in all injured eyes before combined surgery was equal to or <20/1000. Within a 1.1-4.2-year follow-up period, a significant increase, equal to or better than 20/66, in UCVA was observed in six (55%) cases, and in best-corrected VA (BCVA) was observed in nine (82%) cases. Postoperative BCVA was 20/40 or better in seven cases (64%). After combined surgery, the iris returned to its natural round shape or smaller pupil, and the iris-claw IOLs in the 11 eyes were well-positioned on the anterior surface of reconstructed iris. No complications occurred in those patients. Iris reconstruction combined with iris-claw IOL implantation is a safe and efficient procedure for an eye with iris-lens injury in the absence of capsular support.

  17. Three-Dimensional Morphometric Analysis of the Iris by Swept-Source Anterior Segment Optical Coherence Tomography in a Caucasian Population.

    PubMed

    Invernizzi, Alessandro; Giardini, Piero; Cigada, Mario; Viola, Francesco; Staurenghi, Giovanni

    2015-07-01

    We analyzed by swept-source anterior segment optical coherence tomography (SS-ASOCT) the three-dimensional iris morphology in a Caucasian population, and correlated the findings with iris color, iris sectors, subject age, and sex. One eye each from consecutive healthy emmetropic (refractive spherical equivalent ± 3 diopters) volunteers were selected for the study. The enrolled eye underwent standardized anterior segment photography to assess iris color. Iris images were assessed by SS-ASOCT for volume, thickness, width, and pupil size. Sectoral variations of morphometric data among the superior, nasal, inferior, and temporal sectors were recorded. A total of 135 eyes from 57 males and 78 females, age 49 ± 17 years, fulfilled the inclusion criteria. All iris morphometric parameters varied significantly among the different sectors (all P < 0.0001). Iris total volume and thickness were significantly correlated with increasingly darker pigmentation (P < 0.0001, P = 0.0384, respectively). Neither width nor pupil diameter was influenced by iris color. Age did not affect iris volume or thickness; iris width increased and pupil diameter decreased with age (rs = 0.52, rs = -0.58, respectively). There was no effect of sex on iris volume, thickness, or pupil diameter; iris width was significantly greater in males (P = 0.007). Morphology of the iris varied by iris sector, and iris color was associated with differences in iris volume and thickness. Morphological parameter variations associated with iris color, sector, age, and sex can be used to identify pathological changes in suspect eyes. To be effective in clinical settings, construction of iris morphological databases for different ethnic and racial populations is essential.

  18. Iris reconstruction combined with iris-claw intraocular lens implantation for the management of iris-lens injured patients

    PubMed Central

    Hu, Shufang; Wang, Mingling; Xiao, Tianlin; Zhao, Zhenquan

    2016-01-01

    Aim: To study the efficiency and safety of iris reconstruction combined with iris-claw intraocular lens (IOL) implantation in the patients with iris-lens injuries. Settings and Design: Retrospective, noncomparable consecutive case series study. Materials and Methods: Eleven patients (11 eyes) following iris-lens injuries underwent iris reconstructions combined with iris-claw IOL implantations. Clinical data, such as cause and time of injury, visual acuity (VA), iris and lens injuries, surgical intervention, follow-up period, corneal endothelial cell count, and optical coherence tomography, were collected. Results: Uncorrected VA (UCVA) in all injured eyes before combined surgery was equal to or <20/1000. Within a 1.1–4.2-year follow-up period, a significant increase, equal to or better than 20/66, in UCVA was observed in six (55%) cases, and in best-corrected VA (BCVA) was observed in nine (82%) cases. Postoperative BCVA was 20/40 or better in seven cases (64%). After combined surgery, the iris returned to its natural round shape or smaller pupil, and the iris-claw IOLs in the 11 eyes were well-positioned on the anterior surface of reconstructed iris. No complications occurred in those patients. Conclusions: Iris reconstruction combined with iris-claw IOL implantation is a safe and efficient procedure for an eye with iris-lens injury in the absence of capsular support. PMID:27146932

  19. Optical Coherence Tomography Angiography Features of Iris Racemose Hemangioma in 4 Cases.

    PubMed

    Chien, Jason L; Sioufi, Kareem; Ferenczy, Sandor; Say, Emil Anthony T; Shields, Carol L

    2017-10-01

    Optical coherence tomography angiography (OCTA) allows visualization of iris racemose hemangioma course and its relation to the normal iris microvasculature. To describe OCTA features of iris racemose hemangioma. Descriptive, noncomparative case series at a tertiary referral center (Ocular Oncology Service of Wills Eye Hospital). Patients diagnosed with unilateral iris racemose hemangioma were included in the study. Features of iris racemose hemangioma on OCTA. Four eyes of 4 patients with unilateral iris racemose hemangioma were included in the study. Mean patient age was 50 years, all patients were white, and Snellen visual acuity was 20/20 in each case. All eyes had sectoral iris racemose hemangioma without associated iris or ciliary body solid tumor on clinical examination and ultrasound biomicroscopy. By anterior segment OCT, the racemose hemangioma was partially visualized in all cases. By OCTA, the hemangioma was clearly visualized as a uniform large-caliber vascular tortuous loop with intense flow characteristics superimposed over small-caliber radial iris vessels against a background of low-signal iris stroma. The vascular course on OCTA resembled a light bulb filament (filament sign), arising from the peripheral iris (base of light bulb) and forming a tortuous loop on reaching its peak (midfilament) near the pupil (n = 3) or midzonal iris (n = 1), before returning to the peripheral iris (base of light bulb). Intravenous fluorescein angiography performed in 1 eye depicted the iris hemangioma; however, small-caliber radial iris vessels were more distinct on OCTA than intravenous fluorescein angiography. Optical coherence tomography angiography is a noninvasive vascular imaging modality that clearly depicts the looping course of iris racemose hemangioma. Optical coherence tomography angiography depicted fine details of radial iris vessels, not distinct on intravenous fluorescein angiography.

  20. Iris Crypts Influence Dynamic Changes of Iris Volume.

    PubMed

    Chua, Jacqueline; Thakku, Sri Gowtham; Tun, Tin A; Nongpiur, Monisha E; Tan, Marcus Chiang Lee; Girard, Michael J A; Wong, Tien Yin; Quah, Joanne Hui Min; Aung, Tin; Cheng, Ching-Yu

    2016-10-01

    To determine the association of iris surface features with iris volume change after physiologic pupil dilation in adults. Cross-sectional observational study. Chinese adults aged ≥ 50 years without ocular diseases. Digital iris photographs were taken from eyes of each participant and graded for crypts (by number and size) and furrows (by number and circumferential extent) following a standardized grading scheme. Iris color was measured objectively, using the Commission Internationale de l'Eclairage (CIE) L* color parameter (higher value denoting lighter iris). The anterior segment was imaged by swept-source optical coherence tomography (SS-OCT) (Casia; Tomey, Nagoya, Japan) under bright light and dark room conditions. Iris volumes in light and dark conditions were measured with custom semiautomated software, and the change in iris volume was quantified. Associations of the change in iris volume after pupil dilation with underlying iris surface features in right eyes were assessed using linear regression analysis. Iris volume change after physiologic pupil dilation from light to dark condition. A total of 65 Chinese participants (mean age, 59.8±5.7 years) had gradable data for iris surface features. In light condition, higher iris crypt grade was associated independently with smaller iris volume (β [change in iris volume in millimeters per crypt grade increment] = -1.43, 95% confidence interval [CI], -2.26 to -0.59; P = 0.001) and greater reduction of iris volume on pupil dilation (β [change in iris volume in millimeters per crypt grade increment] = 0.23, 95% CI, 0.06-0.40; P = 0.010), adjusting for age, gender, presence of corneal arcus, and change in pupil size. Iris furrows and iris color were not associated with iris volume in light condition or change in iris volume (all P > 0.05). Although few Chinese persons have multiple crypts on their irides, irides with more crypts were significantly thinner and lost more volume on pupil dilation. In view that the latter feature is known to be protective for acute angle-closure attack, it is likely that the macroscopic and microscopic composition of the iris is a contributing feature to angle-closure disease. Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  1. Fuzzy difference-of-Gaussian-based iris recognition method for noisy iris images

    NASA Astrophysics Data System (ADS)

    Kang, Byung Jun; Park, Kang Ryoung; Yoo, Jang-Hee; Moon, Kiyoung

    2010-06-01

    Iris recognition is used for information security with a high confidence level because it shows outstanding recognition accuracy by using human iris patterns with high degrees of freedom. However, iris recognition accuracy can be reduced by noisy iris images with optical and motion blurring. We propose a new iris recognition method based on the fuzzy difference-of-Gaussian (DOG) for noisy iris images. This study is novel in three ways compared to previous works: (1) The proposed method extracts iris feature values using the DOG method, which is robust to local variations of illumination and shows fine texture information, including various frequency components. (2) When determining iris binary codes, image noises that cause the quantization error of the feature values are reduced with the fuzzy membership function. (3) The optimal parameters of the DOG filter and the fuzzy membership function are determined in terms of iris recognition accuracy. Experimental results showed that the performance of the proposed method was better than that of previous methods for noisy iris images.

  2. Enhanced iris recognition method based on multi-unit iris images

    NASA Astrophysics Data System (ADS)

    Shin, Kwang Yong; Kim, Yeong Gon; Park, Kang Ryoung

    2013-04-01

    For the purpose of biometric person identification, iris recognition uses the unique characteristics of the patterns of the iris; that is, the eye region between the pupil and the sclera. When obtaining an iris image, the iris's image is frequently rotated because of the user's head roll toward the left or right shoulder. As the rotation of the iris image leads to circular shifting of the iris features, the accuracy of iris recognition is degraded. To solve this problem, conventional iris recognition methods use shifting of the iris feature codes to perform the matching. However, this increases the computational complexity and level of false acceptance error. To solve these problems, we propose a novel iris recognition method based on multi-unit iris images. Our method is novel in the following five ways compared with previous methods. First, to detect both eyes, we use Adaboost and a rapid eye detector (RED) based on the iris shape feature and integral imaging. Both eyes are detected using RED in the approximate candidate region that consists of the binocular region, which is determined by the Adaboost detector. Second, we classify the detected eyes into the left and right eyes, because the iris patterns in the left and right eyes in the same person are different, and they are therefore considered as different classes. We can improve the accuracy of iris recognition using this pre-classification of the left and right eyes. Third, by measuring the angle of head roll using the two center positions of the left and right pupils, detected by two circular edge detectors, we obtain the information of the iris rotation angle. Fourth, in order to reduce the error and processing time of iris recognition, adaptive bit-shifting based on the measured iris rotation angle is used in feature matching. Fifth, the recognition accuracy is enhanced by the score fusion of the left and right irises. Experimental results on the iris open database of low-resolution images showed that the averaged equal error rate of iris recognition using the proposed method was 4.3006%, which is lower than that of other methods.

  3. Results in Combined Cataract Surgery With Prosthetic Iris Implantation in Patients With Previous Iridocyclectomy for Iris Melanoma.

    PubMed

    Snyder, Michael E; Osher, Robert H; Wladecki, Trisha M; Perez, Mauricio A; Augsburger, James J; Corrêa, Zélia

    2017-03-01

    To present visual and functional results following implantation of iris prosthesis combined with cataract surgery in eyes with previous iridocyclectomy for iris melanoma or presumed iris melanoma. Retrospective noncomparative case series. Sixteen patients (16 eyes) with iris defects after iridocyclectomy for iris melanoma in 15 cases and iris adenoma in 1 case underwent prosthetic iris device implantation surgery. Prosthetic iris implantation was combined with phacoemulsification and intraocular lens (IOL) implantation. The visual acuity, subjective glare and photophobia reduction, anatomic outcome, and complications were reviewed. Best-corrected visual acuity was improved in 13 eyes (81.25%), remained stable in 2 eyes (12.25%), and decreased in 1 eye (6.25%). Photophobia and glare improved in every case except for 1 (93.75%). Notably, after surgery 12 patients (75.00%) reported no photophobia and 10 patients (62.50%) reported no glare. The median postoperative follow-up was 29.5 months, with a minimum of 5 months and a maximum of 189 months. All iris devices were in the correct position, and all eyes achieved the desired anatomic result. The IOL optic edges were covered in all areas by either residual iris or opaque portions of a prosthetic iris device. In patients who have undergone previous iridocyclectomy for presumed iris melanoma, combined cataract surgery and iris prosthesis placement, with or without iris reconstruction, can lead to visual improvement as well as reduction of both glare and photophobia. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Trade off between variable and fixed size normalization in orthogonal polynomials based iris recognition system.

    PubMed

    Krishnamoorthi, R; Anna Poorani, G

    2016-01-01

    Iris normalization is an important stage in any iris biometric, as it has a propensity to trim down the consequences of iris distortion. To indemnify the variation in size of the iris owing to the action of stretching or enlarging the pupil in iris acquisition process and camera to eyeball distance, two normalization schemes has been proposed in this work. In the first method, the iris region of interest is normalized by converting the iris into the variable size rectangular model in order to avoid the under samples near the limbus border. In the second method, the iris region of interest is normalized by converting the iris region into a fixed size rectangular model in order to avoid the dimensional discrepancies between the eye images. The performance of the proposed normalization methods is evaluated with orthogonal polynomials based iris recognition in terms of FAR, FRR, GAR, CRR and EER.

  5. Toward More Accurate Iris Recognition Using Cross-Spectral Matching.

    PubMed

    Nalla, Pattabhi Ramaiah; Kumar, Ajay

    2017-01-01

    Iris recognition systems are increasingly deployed for large-scale applications such as national ID programs, which continue to acquire millions of iris images to establish identity among billions. However, with the availability of variety of iris sensors that are deployed for the iris imaging under different illumination/environment, significant performance degradation is expected while matching such iris images acquired under two different domains (either sensor-specific or wavelength-specific). This paper develops a domain adaptation framework to address this problem and introduces a new algorithm using Markov random fields model to significantly improve cross-domain iris recognition. The proposed domain adaptation framework based on the naive Bayes nearest neighbor classification uses a real-valued feature representation, which is capable of learning domain knowledge. Our approach to estimate corresponding visible iris patterns from the synthesis of iris patches in the near infrared iris images achieves outperforming results for the cross-spectral iris recognition. In this paper, a new class of bi-spectral iris recognition system that can simultaneously acquire visible and near infra-red images with pixel-to-pixel correspondences is proposed and evaluated. This paper presents experimental results from three publicly available databases; PolyU cross-spectral iris image database, IIITD CLI and UND database, and achieve outperforming results for the cross-sensor and cross-spectral iris matching.

  6. Correlation of the Hubble Space Telescope (HST) Space Telescope Imaging Spectrometer (STIS) On-Orbit Data with Pre-launch Predictions and Ground Contamination Controls

    NASA Technical Reports Server (NTRS)

    Hansen, Patricia A.

    2003-01-01

    The Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph (STIS) was deployed on-orbit in February 1997. The contamination program for STIS was stringently controlled as the five-year end-of-life deposition was set at 158, per optical element. Contamination was controlled through materials selection, extensive vacuum outgassing certifications, cleaning techniques, and environmental controls. In addition to ground contamination controls, on-orbit contamination controls were implemented for both the HST servicing mission activities and early post-servicing mission checkout. The extensive contamination control program will be discussed and the STIS on-orbit data will be correlated with the prelaunch analytical predictions.

  7. The Fundamental Structure of Coronal Loops

    NASA Technical Reports Server (NTRS)

    Winebarger, Amy; Warren, Harry; Cirtain, Jonathan; Kobayashi, Ken; Korreck, Kelly; Golub, Leon; Kuzin, Sergey; Walsh, Robert; DePontieu, Bart; Title, Alan; hide

    2012-01-01

    During the past ten years, solar physicists have attempted to infer the coronal heating mechanism by comparing observations of coronal loops with hydrodynamic model predictions. These comparisons often used the addition of sub ]resolution strands to explain the observed loop properties. On July 11, 2012, the High Resolution Coronal Imager (Hi ]C) was launched on a sounding rocket. This instrument obtained images of the solar corona was 0.2 ]0.3'' resolution in a narrowband EUV filter centered around 193 Angstroms. In this talk, we will compare these high resolution images to simultaneous density measurements obtained with the Extreme Ultraviolet Imaging Spectrograph (EIS) on Hinode to determine whether the structures observed with Hi ]C are resolved.

  8. An effective approach for iris recognition using phase-based image matching.

    PubMed

    Miyazawa, Kazuyuki; Ito, Koichi; Aoki, Takafumi; Kobayashi, Koji; Nakajima, Hiroshi

    2008-10-01

    This paper presents an efficient algorithm for iris recognition using phase-based image matching--an image matching technique using phase components in 2D Discrete Fourier Transforms (DFTs) of given images. Experimental evaluation using CASIA iris image databases (versions 1.0 and 2.0) and Iris Challenge Evaluation (ICE) 2005 database clearly demonstrates that the use of phase components of iris images makes possible to achieve highly accurate iris recognition with a simple matching algorithm. This paper also discusses major implementation issues of our algorithm. In order to reduce the size of iris data and to prevent the visibility of iris images, we introduce the idea of 2D Fourier Phase Code (FPC) for representing iris information. The 2D FPC is particularly useful for implementing compact iris recognition devices using state-of-the-art Digital Signal Processing (DSP) technology.

  9. Information Product Development: Data product life cycle links engineering, science, and applications

    NASA Astrophysics Data System (ADS)

    Stavros, E. N.; Owen, S. E.

    2016-12-01

    Information products are assimilated and used to: a) conduct scientific research and b) provide decision support for management and policy. For example, aboveground biomass (i.e. an information product) can be integrated into Earth system models to test hypotheses about the changing world, or used to inform decision-making with respect to natural resource management and policy. Production and dissemination of an information product is referred to as the data product life cycle, which includes: 1) identifying needed information from decision-makers and researchers, 2) engineering an instrument and collecting the raw physical measurements (e.g, number of photons returned), 3) the scientific algorithm(s) for processing the data into an observable (e.g., number of dying trees), and 4) the integration and utilization of that observables by researchers and decision-makers. In this talk, I will discuss the data product life cycle in detail and provide examples from the pre-Hyperspectral Infrared Imager (HyspIRI) airborne campaign and the upcoming NASA-ISRO Synthetic Aperture Radar (NISAR) mission. Examples will focus on information products related to terrestrial ecosystems and natural resource management and will demonstrate that the key to providing information products for advancing scientific understanding and informing decision-makers, is the interdisciplinary integration of science, engineering and applied science - noting that applied science defines the wider impact and adoption of scientific principles by a wider community. As pre-HyspIRI airborne data is for research and development and NISAR is not yet launched, examples will include current plans for developing exemplar data products (from pre-HyspIRI) and the mission Applications Plan (for NISAR). Copyright 2016 California Institute of Technology. All Rights Reserved. We acknowledge support of the US Government, NASA, the Earth Science Division and Terrestrial Ecology program.

  10. AstroBiology Explorer (ABE) MIDEX mission concept

    NASA Astrophysics Data System (ADS)

    Ennico, Kimberly A.; Sandford, Scott; Cox, Sylvia; Ellis, Benton; Gallagher, Dennis J.; Gautier, Nick; Greene, Thomas P.; McCreight, Craig R.; Mills, Gary; Purcell, William R.

    2002-02-01

    The Astrobiology Explorer (ABE) is a MIDEX mission concept under study at NASA's Ames Research Center in collaboration with Ball Aerospace & Technologies, Corp. ABE will conduct IR spectroscopic observations to address important problems in astrobiology, astrochemistry, and astrophysics. The core observational program would make fundamental scientific progress in understanding the distribution, identity, and evolution of ices and organic matter in dense molecular clouds, young forming stellar systems, stellar outflows, the general diffuse ISM, HII regions, Solar System bodies, and external galaxies. The ABE instrument concept includes a 0.6 m aperture Cassegrain telescope and two moderate resolution (R equals 2000-3000) spectrographs covering the 2.5-16 micron spectral region. Large format (1024x1024 pixel or larger) IR detector arrays and bandpass filters will allow each spectrograph to cover an entire octave of spectral range or more per exposure without any moving parts. The telescope will be cooled below 50 K by a cryogenic dewar shielded by a sunshade. The detectors will be cooled to ~8K. The optimum orbital configuration for achieving the scientific objectives of the ABE mission is a low background, 1 AU Earth driftaway orbit requiring a Delta II launch vehicle. This configuration provides a low thermal background and allows adequate communications bandwidth and good access to the entire sky over the ~1-2 year mission lifetime.

  11. Fast Imaging Solar Spectrograph System in New Solar Telescope

    NASA Astrophysics Data System (ADS)

    Park, Y.-D.; Kim, Y. H.; Chae, J.; Goode, P. R.; Cho, K. S.; Park, H. M.; Nah, J. K.; Jang, B. H.

    2010-12-01

    In 2004, Big Bear Solar Observatory in California, USA launched a project for construction of the world's largest aperture solar telescope (D = 1.6m) called New Solar Telescope(NST). University of Hawaii (UH) and Korea Astronomy and Space Science Institute(KASI) partly collaborate on the project. NST is a designed off-axis parabolic Gregorian reflector with very high spatial resolution(0.07 arcsec at 5000A) and is equipped with several scientific instruments such as Visible Imaging Magnetograph (VIM), InfraRed Imaging Magnetograph IRIM), and so on. Since these scientific instruments are focused on studies of the solar photosphere, we need a post-focus instrument for the NST to study the fine structures and dynamic patterns of the solar chromosphere and low Transition Region (TR) layer, including filaments/prominences, spicules, jets, micro flares, etc. For this reason, we developed and installed a fast imaging solar spectrograph(FISS) system on the NST withadvantages of achieving compact design with high spectral resolution and small aberration as well as recording many solar spectral lines in a single and/or dual band mode. FISS was installed in May, 2010 and now we carry out a test observation. In this talk, we introduce the FISS system and the results of the test observation after FISS installation.

  12. Iris Location Algorithm Based on the CANNY Operator and Gradient Hough Transform

    NASA Astrophysics Data System (ADS)

    Zhong, L. H.; Meng, K.; Wang, Y.; Dai, Z. Q.; Li, S.

    2017-12-01

    In the iris recognition system, the accuracy of the localization of the inner and outer edges of the iris directly affects the performance of the recognition system, so iris localization has important research meaning. Our iris data contain eyelid, eyelashes, light spot and other noise, even the gray transformation of the images is not obvious, so the general methods of iris location are unable to realize the iris location. The method of the iris location based on Canny operator and gradient Hough transform is proposed. Firstly, the images are pre-processed; then, calculating the gradient information of images, the inner and outer edges of iris are coarse positioned using Canny operator; finally, according to the gradient Hough transform to realize precise localization of the inner and outer edge of iris. The experimental results show that our algorithm can achieve the localization of the inner and outer edges of the iris well, and the algorithm has strong anti-interference ability, can greatly reduce the location time and has higher accuracy and stability.

  13. Exploring the feasibility of iris recognition for visible spectrum iris images obtained using smartphone camera

    NASA Astrophysics Data System (ADS)

    Trokielewicz, Mateusz; Bartuzi, Ewelina; Michowska, Katarzyna; Andrzejewska, Antonina; Selegrat, Monika

    2015-09-01

    In the age of modern, hyperconnected society that increasingly relies on mobile devices and solutions, implementing a reliable and accurate biometric system employing iris recognition presents new challenges. Typical biometric systems employing iris analysis require expensive and complicated hardware. We therefore explore an alternative way using visible spectrum iris imaging. This paper aims at answering several questions related to applying iris biometrics for images obtained in the visible spectrum using smartphone camera. Can irides be successfully and effortlessly imaged using a smartphone's built-in camera? Can existing iris recognition methods perform well when presented with such images? The main advantage of using near-infrared (NIR) illumination in dedicated iris recognition cameras is good performance almost independent of the iris color and pigmentation. Are the images obtained from smartphone's camera of sufficient quality even for the dark irides? We present experiments incorporating simple image preprocessing to find the best visibility of iris texture, followed by a performance study to assess whether iris recognition methods originally aimed at NIR iris images perform well with visible light images. To our best knowledge this is the first comprehensive analysis of iris recognition performance using a database of high-quality images collected in visible light using the smartphones flashlight together with the application of commercial off-the-shelf (COTS) iris recognition methods.

  14. The Immune Pathogenesis of Immune Reconstitution Inflammatory Syndrome Associated with Highly Active Antiretroviral Therapy in AIDS

    PubMed Central

    Zhou, Huaying; He, Yan; Chen, Zi; He, Bo; He, Mei

    2014-01-01

    Abstract The present study investigated the immunological pathogenesis of immune reconstitution inflammatory syndrome (IRIS) in acquired immunodeficiency syndrome (AIDS) patients undergoing highly active antiretroviral therapy (HAART). A total of 238 patients with AIDS who received initial HAART were included in this prospective cohort study. Blood samples were collected immediately, at baseline, at week 12, and at week 24 after initial HAART and at the onset of IRIS. Lymphocyte subsets, Th1 and Th2 cytokines, and interleukin (IL)-7 levels were measured by flow cytometry or ELISA. Among the 238 patients with AIDS who received HAART, 47 patients developed IRIS. The percentages of CD4+ and CD8+ naive, memory, and activated cells exhibited no significant differences between AIDS patients with and without IRIS 24 weeks after initial HAART. The percentage of CD4+CD25+Foxp3+ regulatory T cells was lower in IRIS patients than in non-IRIS patients before HAART, 12 weeks after HAART, 24 weeks after HAART, and at the onset of IRIS. IL-2 and interferon (IFN)-γ levels were significantly higher at week 4 and at the onset of IRIS in IRIS patients than in non-IRIS patients. In contrast, IL-4 and IL-10 levels were significantly lower at week 4 and at the onset of IRIS in IRIS patients than in non-IRIS patients. Plasma IL-7 decreased gradually with the progression of HAART. The level of IL-7 was higher in IRIS patients than in non-IRIS patients at all follow-up time points. An imbalance of Th1/Th2 cytokines, a consistently low CD+CD25+Fox3+ percentage, and a high IL-7 level may be crucial in the pathogenesis of IRIS in AIDS patients who had received HAART. PMID:25131160

  15. On techniques for angle compensation in nonideal iris recognition.

    PubMed

    Schuckers, Stephanie A C; Schmid, Natalia A; Abhyankar, Aditya; Dorairaj, Vivekanand; Boyce, Christopher K; Hornak, Lawrence A

    2007-10-01

    The popularity of the iris biometric has grown considerably over the past two to three years. Most research has been focused on the development of new iris processing and recognition algorithms for frontal view iris images. However, a few challenging directions in iris research have been identified, including processing of a nonideal iris and iris at a distance. In this paper, we describe two nonideal iris recognition systems and analyze their performance. The word "nonideal" is used in the sense of compensating for off-angle occluded iris images. The system is designed to process nonideal iris images in two steps: 1) compensation for off-angle gaze direction and 2) processing and encoding of the rotated iris image. Two approaches are presented to account for angular variations in the iris images. In the first approach, we use Daugman's integrodifferential operator as an objective function to estimate the gaze direction. After the angle is estimated, the off-angle iris image undergoes geometric transformations involving the estimated angle and is further processed as if it were a frontal view image. The encoding technique developed for a frontal image is based on the application of the global independent component analysis. The second approach uses an angular deformation calibration model. The angular deformations are modeled, and calibration parameters are calculated. The proposed method consists of a closed-form solution, followed by an iterative optimization procedure. The images are projected on the plane closest to the base calibrated plane. Biorthogonal wavelets are used for encoding to perform iris recognition. We use a special dataset of the off-angle iris images to quantify the performance of the designed systems. A series of receiver operating characteristics demonstrate various effects on the performance of the nonideal-iris-based recognition system.

  16. An automatic iris occlusion estimation method based on high-dimensional density estimation.

    PubMed

    Li, Yung-Hui; Savvides, Marios

    2013-04-01

    Iris masks play an important role in iris recognition. They indicate which part of the iris texture map is useful and which part is occluded or contaminated by noisy image artifacts such as eyelashes, eyelids, eyeglasses frames, and specular reflections. The accuracy of the iris mask is extremely important. The performance of the iris recognition system will decrease dramatically when the iris mask is inaccurate, even when the best recognition algorithm is used. Traditionally, people used the rule-based algorithms to estimate iris masks from iris images. However, the accuracy of the iris masks generated this way is questionable. In this work, we propose to use Figueiredo and Jain's Gaussian Mixture Models (FJ-GMMs) to model the underlying probabilistic distributions of both valid and invalid regions on iris images. We also explored possible features and found that Gabor Filter Bank (GFB) provides the most discriminative information for our goal. Finally, we applied Simulated Annealing (SA) technique to optimize the parameters of GFB in order to achieve the best recognition rate. Experimental results show that the masks generated by the proposed algorithm increase the iris recognition rate on both ICE2 and UBIRIS dataset, verifying the effectiveness and importance of our proposed method for iris occlusion estimation.

  17. The fast iris image clarity evaluation based on Tenengrad and ROI selection

    NASA Astrophysics Data System (ADS)

    Gao, Shuqin; Han, Min; Cheng, Xu

    2018-04-01

    In iris recognition system, the clarity of iris image is an important factor that influences recognition effect. In the process of recognition, the blurred image may possibly be rejected by the automatic iris recognition system, which will lead to the failure of identification. Therefore it is necessary to evaluate the iris image definition before recognition. Considered the existing evaluation methods on iris image definition, we proposed a fast algorithm to evaluate the definition of iris image in this paper. In our algorithm, firstly ROI (Region of Interest) is extracted based on the reference point which is determined by using the feature of the light spots within the pupil, then Tenengrad operator is used to evaluate the iris image's definition. Experiment results show that, the iris image definition algorithm proposed in this paper could accurately distinguish the iris images of different clarity, and the algorithm has the merit of low computational complexity and more effectiveness.

  18. A gallery approach for off-angle iris recognition

    NASA Astrophysics Data System (ADS)

    Karakaya, Mahmut; Yoldash, Rashiduddin; Boehnen, Christopher

    2015-05-01

    It has been proven that hamming distance score between frontal and off-angle iris images of same eye differs in iris recognition system. The distinction of hamming distance score is caused by many factors such as image acquisition angle, occlusion, pupil dilation, and limbus effect. In this paper, we first study the effect of the angle variations between iris plane and the image acquisition systems. We present how hamming distance changes for different off-angle iris images even if they are coming from the same iris. We observe that increment in acquisition angle of compared iris images causes the increment in hamming distance. Second, we propose a new technique in off-angle iris recognition system that includes creating a gallery of different off-angle iris images (such as, 0, 10, 20, 30, 40, and 50 degrees) and comparing each probe image with these gallery images. We will show the accuracy of the gallery approach for off-angle iris recognition.

  19. Iris segmentation using an edge detector based on fuzzy sets theory and cellular learning automata.

    PubMed

    Ghanizadeh, Afshin; Abarghouei, Amir Atapour; Sinaie, Saman; Saad, Puteh; Shamsuddin, Siti Mariyam

    2011-07-01

    Iris-based biometric systems identify individuals based on the characteristics of their iris, since they are proven to remain unique for a long time. An iris recognition system includes four phases, the most important of which is preprocessing in which the iris segmentation is performed. The accuracy of an iris biometric system critically depends on the segmentation system. In this paper, an iris segmentation system using edge detection techniques and Hough transforms is presented. The newly proposed edge detection system enhances the performance of the segmentation in a way that it performs much more efficiently than the other conventional iris segmentation methods.

  20. An Iris Segmentation Algorithm based on Edge Orientation for Off-angle Iris Recognition

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

    Karakaya, Mahmut; Barstow, Del R; Santos-Villalobos, Hector J

    Iris recognition is known as one of the most accurate and reliable biometrics. However, the accuracy of iris recognition systems depends on the quality of data capture and is negatively affected by several factors such as angle, occlusion, and dilation. In this paper, we present a segmentation algorithm for off-angle iris images that uses edge detection, edge elimination, edge classification, and ellipse fitting techniques. In our approach, we first detect all candidate edges in the iris image by using the canny edge detector; this collection contains edges from the iris and pupil boundaries as well as eyelash, eyelids, iris texturemore » etc. Edge orientation is used to eliminate the edges that cannot be part of the iris or pupil. Then, we classify the remaining edge points into two sets as pupil edges and iris edges. Finally, we randomly generate subsets of iris and pupil edge points, fit ellipses for each subset, select ellipses with similar parameters, and average to form the resultant ellipses. Based on the results from real experiments, the proposed method shows effectiveness in segmentation for off-angle iris images.« less

  1. PLATEAU IRIS SYNDROME--CASE SERIES.

    PubMed

    Feraru, Crenguta Ioana; Pantalon, Anca Delia; Chiselita, Dorin; Branisteanu, Daniel

    2015-01-01

    Plateau iris is characterized by closing the anterior chamber angle due to a large ciliary body or due to its anterior insertion that alters the position of iris periphery in respect to the trabecular meshwork. There are two aspects that need to be differentiated: plateau iris configuration and plateau iris syndrome. The first describes a situation when the iris root is flat and the anterior chamber is not shallow, the latter refers to a post laser iridotomy condition in which a patent iridotomy has removed the relative pupillary block, but goniscopically confirmed angle closure recurs without central shallowing of the anterior chamber. Isolated plateau iris syndrome is rare compared to plateau iris configuration. We hereby present two case reports of plateau iris syndrome in young patients who came to an ophthalmologic consult by chance.

  2. Iris texture traits show associations with iris color and genomic ancestry.

    PubMed

    Quillen, Ellen E; Guiltinan, Jenna S; Beleza, Sandra; Rocha, Jorge; Pereira, Rinaldo W; Shriver, Mark D

    2011-01-01

    This study seeks to identify associations among genomic biogeographic ancestry (BGA), quantitative iris color, and iris texture traits contributing to population-level variation in these phenotypes. DNA and iris photographs were collected from 300 individuals across three variably admixed populations (Portugal, Brazil, and Cape Verde). Two raters scored the photos for pigmentation spots, Fuchs' crypts, contraction furrows, and Wolflinn nodes. Iris color was quantified from RGB values. Maximum likelihood estimates of individual BGA were calculated from 176 ancestry informative markers. Pigmentation spots, Fuchs' crypts, contraction furrows, and iris color show significant positive correlation with increasing European BGA. Only contraction furrows are correlated with iris color. The relationship between BGA and iris texture illustrates a genetic contribution to this population-level variation. Copyright © 2011 Wiley-Liss, Inc.

  3. Comparison and evaluation of datasets for off-angle iris recognition

    NASA Astrophysics Data System (ADS)

    Kurtuncu, Osman M.; Cerme, Gamze N.; Karakaya, Mahmut

    2016-05-01

    In this paper, we investigated the publicly available iris recognition datasets and their data capture procedures in order to determine if they are suitable for the stand-off iris recognition research. Majority of the iris recognition datasets include only frontal iris images. Even if a few datasets include off-angle iris images, the frontal and off-angle iris images are not captured at the same time. The comparison of the frontal and off-angle iris images shows not only differences in the gaze angle but also change in pupil dilation and accommodation as well. In order to isolate the effect of the gaze angle from other challenging issues including dilation and accommodation, the frontal and off-angle iris images are supposed to be captured at the same time by using two different cameras. Therefore, we developed an iris image acquisition platform by using two cameras in this work where one camera captures frontal iris image and the other one captures iris images from off-angle. Based on the comparison of Hamming distance between frontal and off-angle iris images captured with the two-camera- setup and one-camera-setup, we observed that Hamming distance in two-camera-setup is less than one-camera-setup ranging from 0.05 to 0.001. These results show that in order to have accurate results in the off-angle iris recognition research, two-camera-setup is necessary in order to distinguish the challenging issues from each other.

  4. The best bits in an iris code.

    PubMed

    Hollingsworth, Karen P; Bowyer, Kevin W; Flynn, Patrick J

    2009-06-01

    Iris biometric systems apply filters to iris images to extract information about iris texture. Daugman's approach maps the filter output to a binary iris code. The fractional Hamming distance between two iris codes is computed and decisions about the identity of a person are based on the computed distance. The fractional Hamming distance weights all bits in an iris code equally. However, not all the bits in an iris code are equally useful. Our research is the first to present experiments documenting that some bits are more consistent than others. Different regions of the iris are compared to evaluate their relative consistency, and contrary to some previous research, we find that the middle bands of the iris are more consistent than the inner bands. The inconsistent-bit phenomenon is evident across genders and different filter types. Possible causes of inconsistencies, such as segmentation, alignment issues, and different filters are investigated. The inconsistencies are largely due to the coarse quantization of the phase response. Masking iris code bits corresponding to complex filter responses near the axes of the complex plane improves the separation between the match and nonmatch Hamming distance distributions.

  5. The Sharjah Center for Astronomy and Space Sciences (SCASS 2015): Concept and Resources

    NASA Astrophysics Data System (ADS)

    Naimiy, Hamid M. K. Al

    2015-08-01

    The Sharjah Center for Astronomy and Space Sciences (SCASS) was launched this year 2015 at the University of Sharjah in the UAE. The center will serve to enrich research in the fields of astronomy and space sciences, promote these fields at all educational levels, and encourage community involvement in these sciences. SCASS consists of:The Planetarium: Contains a semi-circle display screen (18 meters in diameter) installed at an angle of 10° which displays high-definition images using an advanced digital display system consisting of seven (7) high-performance light-display channels. The Planetarium Theatre offers a 200-seat capacity with seats placed at highly calculated angles. The Planetarium also contains an enormous star display (Star Ball - 10 million stars) located in the heart of the celestial dome theatre.The Sharjah Astronomy Observatory: A small optical observatory consisting of a reflector telescope 45 centimeters in diameter to observe the galaxies, stars and planets. Connected to it is a refractor telescope of 20 centimeters in diameter to observe the sun and moon with highly developed astronomical devices, including a digital camera (CCD) and a high-resolution Echelle Spectrograph with auto-giving and remote calibration ports.Astronomy, space and physics educational displays for various age groups include:An advanced space display that allows for viewing the universe during four (4) different time periods as seen by:1) The naked eye; 2) Galileo; 3) Spectrographic technology; and 4) The space technology of today.A space technology display that includes space discoveries since the launching of the first satellite in 1940s until now.The Design Concept for the Center (450,000 sq. meters) was originated by HH Sheikh Sultan bin Mohammed Al Qasimi, Ruler of Sharjah, and depicts the dome as representing the sun in the middle of the center surrounded by planetary bodies in orbit to form the solar system as seen in the sky.

  6. VizieR Online Data Catalog: Bubble HII region Sh2-39 (N5) (Duronea+, 2017)

    NASA Astrophysics Data System (ADS)

    Duronea, N. U.; Cappa, C. E.; Bronfman, L.; Borissova, J.; Gromadzki, M.; Kuhn, M. A.

    2017-06-01

    The molecular observations were carried out in August 2015 with the 10m Atacama Submillimeter Telescope Experiment (ASTE). We used DASH345, a two sideband single-polarization heterodyne receiver, tunable in LO frequency range from 327GHz to 370GHz at observable frequency range from 321GHz to 376GHz. The XF digital spectrometer was set to a bandwidth and spectral resolution of 128MHz and 125KHz, respectively. The spectral velocity resolution was 0.11km/s, the half power beamwidth (HPBW) is ~22", and the main beam efficiency (mb) is 0.65. Observations were made using the on-the-fly (OTF) mode with two orthogonal scan directions along RA and Dec. (J2000) centered on RA, Dec.(J2000)= (18:17:02.1, -18:40:19). We observed simultaneously the lines CO(3-2) (345.796GHz) and HCO+(4-3) (356.734) in a region of ~17'x17' (see Fig. 1). The spectra were reduced with NOSTAR2 using the standard procedure. The brightest star projected at the center of [BDS2003] 6 (2MASS J18165113-1841488) was observed on August 2016 with Astronomy Research using the Cornell Infra Red Imaging Spectrograph (ARCoIRIS), a cross-dispersed, single-object, longslit, infrared imaging spectrograph,mounted on Blanco 4-m Telescope, CTIO. The spectra cover a simultaneous wavelength range of 0.80 to 2.47um, at a spectral resolution of about 3500 λ{δλ, encompassing the entire zYJHK photometric range. The spectrum was taken with 480 sec integration time, at 1.03 average airmass. The HD163336 telluric A0 V standard is observed immediately after target. The basic steps of the reduction procedure are described in Chene et al. (2012A&A...545A..54C, Cat. J/A+A/545/A54, 2013A&A...549A..98C). We used the corresponding pipeline. (3 data files).

  7. Prospects for Measuring Supermassive Black Hole Masses with Future Extremely Large Telescopes

    NASA Astrophysics Data System (ADS)

    Do, Tuan; Wright, S. A.; Barton, E. J.; Barth, A. J.; Simard, L.; Larkin, J. E.; Moore, A.

    2013-01-01

    The next generation of giant-segmented mirror telescopes (> 20 m) will enable us to observe galactic nuclei at much higher angular resolution and sensitivity than ever before. These capabilities will introduce a revolutionary shift in our understanding of the origin and evolution of supermassive black holes by enabling more precise black hole mass measurements in a mass range that is unreachable today. We present simulations and predictions of the observations of nuclei that will be made with the Thirty Meter Telescope (TMT) and the adaptive optics assisted integral-field spectrograph IRIS. These simulations, for the first time, use realistic values for the sky, telescope, adaptive optics system, and instrument, to determine the expected signal-to-noise of a range of possible targets spanning intermediate mass black holes of ~10^4 M⊙ to the most massive black holes known today of >10^10 M⊙. We find that future integral-field spectrographs will be able to observe Milky Way-mass black holes out the distance of the Virgo cluster, and will allow us to observe many more brightest-cluster galaxies where the most massive black holes are thought to reside. We also evaluate how well the kinematic moments of the velocity distributions can be constrained at different spectral resolutions and plate scales. We find that a spectral resolution of ~8000 will be necessary to measure the masses of IMBHs. We find by using the SDSS DR7 catalog of galaxies that over 4000 massive black holes will be observable at distances between 0.005 < z < 0.3 with the estimated sensitivity and angular resolution of TMT. These observations will provide the most accurate dynamical mass measurements of black holes to enable the study of their demography, address the origin of the M_bh-σ and M_bh - L relationships, and the origins and evolution of black holes through cosmic time.

  8. Toward accurate and fast iris segmentation for iris biometrics.

    PubMed

    He, Zhaofeng; Tan, Tieniu; Sun, Zhenan; Qiu, Xianchao

    2009-09-01

    Iris segmentation is an essential module in iris recognition because it defines the effective image region used for subsequent processing such as feature extraction. Traditional iris segmentation methods often involve an exhaustive search of a large parameter space, which is time consuming and sensitive to noise. To address these problems, this paper presents a novel algorithm for accurate and fast iris segmentation. After efficient reflection removal, an Adaboost-cascade iris detector is first built to extract a rough position of the iris center. Edge points of iris boundaries are then detected, and an elastic model named pulling and pushing is established. Under this model, the center and radius of the circular iris boundaries are iteratively refined in a way driven by the restoring forces of Hooke's law. Furthermore, a smoothing spline-based edge fitting scheme is presented to deal with noncircular iris boundaries. After that, eyelids are localized via edge detection followed by curve fitting. The novelty here is the adoption of a rank filter for noise elimination and a histogram filter for tackling the shape irregularity of eyelids. Finally, eyelashes and shadows are detected via a learned prediction model. This model provides an adaptive threshold for eyelash and shadow detection by analyzing the intensity distributions of different iris regions. Experimental results on three challenging iris image databases demonstrate that the proposed algorithm outperforms state-of-the-art methods in both accuracy and speed.

  9. Immune reconstitution inflammatory syndrome associated with toxoplasmic encephalitis in HIV-infected patients.

    PubMed

    van Bilsen, Ward P H; van den Berg, Charlotte H S B; Rijnders, Bart J A; Brinkman, Kees; Mulder, Jan W; Gelinck, Luc B S; Hoepelman, Andy I M; Wit, Ferdinand W N M; van de Beek, Diederik; Prins, Jan M

    2017-06-19

    To investigate the incidence and risk factors of immune reconstitution inflammatory syndrome (IRIS) associated with toxoplasmic encephalitis (TE) in patients starting combination antiretroviral therapy (cART). A historical multicenter cohort study. We included all HIV-infected patients diagnosed with toxoplasmic encephalitis in six Dutch hospitals between 1996 and 2016. Diagnosis of TE-IRIS was made using predefined IRIS criteria. We distinguished paradoxical TE-IRIS (worsening of underlying treated infection) from unmasking TE-IRIS (unmasking of subclinical infection after start of cART). We compared CD4 cell count, plasma viral load and timing of cART initiation between patients with and without paradoxical TE-IRIS. A total of 211 toxoplasmic encephalitis cases were included. Among 143 cases at risk for paradoxical TE-IRIS, we identified five cases of paradoxical TE-IRIS (3.5%). In six other cases, we could not differentiate paradoxical TE-IRIS from recurrence of disease due to inadequate secondary Toxoplasma prophylaxis. There was no difference in time between start of toxoplasmic encephalitis treatment and cART initiation for patients who did or did not develop paradoxical TE-IRIS (P = 0.50). Within the group of 2228 patients who started cART while having a CD4 cell count below 200 × 10 cells/l and receiving adequate primary prophylaxis, we identified eight cases of unmasking TE-IRIS (0.36%). Unmasking TE-IRIS could not be differentiated from a newly occurring toxoplasmic encephalitis in six other patients, as they were not receiving adequate primary prophylaxis against Toxoplasma. Unmasking TE-IRIS was rare in this cohort, whereas paradoxical TE-IRIS did occur more often. We found no relationship between the timing of cART initiation and the occurrence of paradoxical TE-IRIS.

  10. The International Reference Ionosphere - Climatological Standard for the Ionosphere

    NASA Technical Reports Server (NTRS)

    Bilitza, Dieter

    2006-01-01

    The International Reference Ionosphere (IRI) a joint project of URSI and COSPAR is the defacto standard for a climatological specification of ionospheric parameters. IRI is based on a wide range of ground and space data and has been steadily improved since its inception in 1969 with the ever-increasing volume of ionospheric data and with better mathematical descriptions of the observed global and temporal variation patterns. The IRI model has been validated with a large amount of data including data from the most recent ionospheric satellites (KOMPSAT, ROCSAT and TIMED) and data from global network of ionosondes. Several IRI teams are working on specific aspects of the IRI modeling effort including an improved representation of the topside ionosphere with a seamless transition to the plasmasphere, a new effort to represent the global variation of F2 peak parameters using the Neural Network (NN) technique, and the inclusion of several additional parameters in IRI, e.g., spread-F probability and ionospheric variability. Annual IRI workshops are the forum for discussions of these efforts and for all science activities related to IRI as well as applications of the IRI model in engineering and education. In this paper I will present a status report about the IRI effort with special emphasis on the presentations and results from the most recent IRI Workshops (Paris, 2004; Tortosa, 2005) and on the most important ongoing IRI activities. I will discuss the latest version of the IRI model, IRI-2006, highlighting the most recent changes and additions. Finally, the talk will review some of the applications of the IRI model with special emphasis on the use for radiowave propagation studies and communication purposes.

  11. Association of iris surface features with iris parameters assessed by swept-source optical coherence tomography in Asian eyes.

    PubMed

    Tun, Tin A; Chua, Jacqueline; Shi, Yuan; Sidhartha, Elizabeth; Thakku, Sri Gowtham; Shei, William; Tan, Marcus Chiang Lee; Quah, Joanne Hui Min; Aung, Tin; Cheng, Ching-Yu

    2016-12-01

    To characterise the association of iris surface features (crypts, furrows and colour) with iris volume and curvature assessed by swept-source optical coherence tomography (SSOCT) in Asian eyes. Iris crypts (by number and size) and furrows (by number and circumferential extent) were graded from iris photographs. Iris colour was measured by a customised algorithm written on MATLAB (MathWorks, Natick, Massachusetts, USA). The iris was imaged by SSOCT (SS-1000, CASIA, Tomey, Nagoya, Japan). The associations of surface features with iris parameters were analysed using a generalised estimating equation. A total of 1704 subjects (3297 eyes) were included in the analysis. The majority was Chinese (86.4%), and 63.2% were females, and their mean age (±SD) was 61.4±6.6 years. After adjusting for age, sex, ethnicity, pupil size and corneal arcus, higher iris crypt grade was independently associated with smaller iris volume (β=-0.54, p<0.001), whereas darker irides and higher iris furrow grade were associated with larger iris volume (β=-0.041, p<0.001) and (β=0.233, p<0.001), respectively. Lighter coloured irides with more crypts and/or more furrows were also associated with less convexity (crypts: β=-0.003, p=0.03; furrows: β=-0.004, p=0.007; and colour: β=-0.001, p=0.005). Iris surface features were highly correlated with iris volume and curvature. Irides with more crypts have a smaller volume; and darker irides with more furrows have a larger volume. Lighter irides with more crypts and/or furrows have less convexity. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  12. CUSP-SHAPED STRUCTURE OF A JET OBSERVED BY IRIS AND SDO

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

    Zhang, Yuzong; Zhang, Jun, E-mail: yuzong@nao.cas.cn, E-mail: zjun@nao.cas.cn

    2017-01-01

    On 2014 August 29, the trigger and evolution of a cusp-shaped jet were captured in detail at 1330 Å by the Interface Region Imaging Spectrograph . At first, two neighboring mini-prominences arose in turn from the low solar atmosphere and collided with a loop-like system over them. The collisions between the loop-like system and the mini-prominences lead to the blowout, and then a cusp-shaped jet formed with a spire and an arch-base. In the spire, many brightening blobs originating from the junction between the spire and the arch-base moved upward in a rotating manner and then in a straight line inmore » the late phase of the jet. In the arch-base, dark and bright material simultaneously tracked in a fan-like structure, and the majority of the material moved along the fan's threads. At the later phase of the jet's evolution, bidirectional flows emptied the arch-base, while downflows emptied the spire, thus making the jet entirely vanish. The extremely detailed observations in this study shed new light on how magnetic reconnection alters the inner topological structure of a jet and provides a beneficial complement for understanding current jet models.« less

  13. VizieR Online Data Catalog: Line list for stellar chemical abundances (Bedell+, 2014)

    NASA Astrophysics Data System (ADS)

    Bedell, M.; Melendez, J.; Bean, J. L.; Ramirez, I.; Leite, P.; Asplund, M.

    2017-05-01

    The five solar spectra used in this analysis were obtained with very high resolution and signal-to-noise ratios (S/Ns) characteristic of data used in past stellar abundance analyses. Two spectra were taken with the Echelle SpectroPolarimetric Device for the Observation of Stars (ESPaDOnS) instrument (Donati 2003, Solar Polarization (ASP Conf. Ser. 307), ed. J. Trujillo-Bueno & J. Sanchez Almeida (San Francisco, CA: ASP), 41) at the 3.6 m Canada-France-Hawaii Telescope on the night of 2013 March 4. The asteroids Ceres and Vesta were each observed in "star only" mode at a spectral resolving power R=81000. The remaining three solar spectra were taken with the Magellan Inamori Kyocera Echelle (MIKE) spectrograph (Bernstein et al. 2003SPIE.4841.1694B) at the 6.5 m Magellan Clay telescope. The asteroid Vesta was observed twice and Iris was observed once during three separate observing runs spanning January to September of 2011. All observations were carried out in MIKE's standard setup with the 0.35 arcsec width slit, giving a spectral resolving power of R=83000 on the blue CCD and 65000 on the red CCD. (1 data file).

  14. ISO Technical Specification for the Ionosphere -IRI Recent Activities

    NASA Astrophysics Data System (ADS)

    Bilitza, Dieter; Reinisch, Bodo; Tamara, Gulyaeva

    ISO Technical Specification TS 16457 recommends the International Reference Ionosphere (IRI) for the specification of ionospheric densities and temperatures. We review the latest develop-ments towards improving the IRI model and the newest version of the model IRI-2010. IRI-2010 includes several important improvements and additions. This presentation introduces these changes and discusses their benefits. The changes affect primarily the density profiles in the bottomside ionosphere and the density and height of the F2 peak, the point of highest density in the ionosphere. An important new addition to the model is the inclusion of auroral boundaries and their movement with magnetic activity. We will also discuss the status of other ongoing IRI activities and some of the recent applications of the IRI model. The homepage for the IRI project is at http://IRI.gsfc.nasa.gov/.

  15. Starshade mechanical design for the Habitable Exoplanet imaging mission concept (HabEx)

    NASA Astrophysics Data System (ADS)

    Arya, Manan; Webb, David; McGown, James; Lisman, P. Douglas; Shaklan, Stuart; Bradford, S. Case; Steeves, John; Hilgemann, Evan; Trease, Brian; Thomson, Mark; Warwick, Steve; Freebury, Gregg; Gull, Jamie

    2017-09-01

    An external occulter for starlight suppression - a starshade - flying in formation with the Habitable Exoplanet Imaging Mission Concept (HabEx) space telescope could enable the direct imaging and spectrographic characterization of Earthlike exoplanets in the habitable zone. This starshade is flown between the telescope and the star, and suppresses stellar light sufficiently to allow the imaging of the faint reflected light of the planet. This paper presents a mechanical architecture for this occulter, which must stow in a 5 m-diameter launch fairing and then deploy to about a 80 m-diameter structure. The optical performance of the starshade requires that the edge profile is accurate and stable. The stowage and deployment of the starshade to meet these requirements present unique challenges that are addressed in this proposed architecture. The mechanical architecture consists of a number of petals attached to a deployable perimeter truss, which is connected to central hub using tensioned spokes. The petals are furled around the stowed perimeter truss for launch. Herein is described a mechanical design solution that supports an 80 m-class starshade for flight as part of HabEx.

  16. Mapping alteration using imagery from the Tiangong-1 hyperspectral spaceborne system: Example for the Jintanzi gold province, China

    NASA Astrophysics Data System (ADS)

    Liu, Lei; Feng, Jilu; Rivard, Benoit; Xu, Xinliang; Zhou, Jun; Han, Ling; Yang, Junlu; Ren, Guangli

    2018-02-01

    The Tiangong-1 Hyperspectral Imager (HSI) is a relatively new spaceborne hyperspectral remote sensing system that was launched by the Chinese government on September 29th 2011. The system has 64 shortwave infrared (SWIR) spectral bands (1000-2500 nm) and imagery is at a spatial resolution of 20 m. This study represents an evaluation of Tiangong-1 data for the production of alteration mineral maps. Alteration mineral maps resulting from the analysis of Tiangong-1 HSI data and airborne SASI (Shortwave infrared Airborne Spectrographic Imager) data are compared for the Jintanzi area, Beishan, Gansu province, northwest China where gold bearing veins are documented. The results illustrate the detection of muscovite, kaolinite, chlorite, epidote, calcite and dolomite from Tiangong-1 HSI data and most anomalies seen in the airborne SASI data are captured. The Tiangong-1 data appears to be well suited for the detection of surface mineralogy in support of regional mapping and exploration. The data complements that which will be offered by the Chinese GF-5 Hyperspectral Imager and the German EnMAP system, both scheduled for launch in 2018.

  17. Numerical simulations of stellar jets and comparison between synthetic and observed maps: clues to the launch mechanism

    NASA Astrophysics Data System (ADS)

    Rubini, F.; Maurri, L.; Inghirami, G.; Bacciotti, F.; Del Zanna, L.

    2014-07-01

    High angular resolution spectra obtained with the Hubble Space Telescope Imaging Spectrograph (HST/STIS) provide rich morphological and kinematical information about the stellar jet phenomenon, which allows us to test theoretical models efficiently. In this work, numerical simulations of stellar jets in the propagation region are executed with the PLUTO code, by adopting inflow conditions that arise from former numerical simulations of magnetized outflows, accelerated by the disk-wind mechanism in the launching region. By matching the two regions, information about the magneto-centrifugal accelerating mechanism underlying a given astrophysical object can be extrapolated by comparing synthetic and observed position-velocity diagrams. We show that quite different jets, like those from the young T Tauri stars DG-Tau and RW-Aur, may originate from the same disk-wind model for different configurations of the magnetic field at the disk surface. This result supports the idea that all the observed jets may be generated by the same mechanism. Appendix A is available in electronic form at http://www.aanda.org

  18. Optical Coherence Tomography Angiography Characteristics of Iris Melanocytic Tumors

    PubMed Central

    Skalet, Alison H.; Li, Yan; Lu, Chen D.; Jia, Yali; Lee, ByungKun; Husvogt, Lennart; Maier, Andreas; Fujimoto, James G.; Thomas, Charles R.; Huang, David

    2016-01-01

    Objective To evaluate tumor vasculature with optical coherence tomography (OCT) angiography (OCTA) in malignant iris melanomas and benign iris lesions. Design Cross-sectional observational clinical study. Participants Patients with iris lesions and healthy volunteers. Methods Eyes were imaged using OCTA systems operating at 1050 and 840 nm wavelengths. Three-dimensional OCTA scans were acquired. Iris melanomas patients treated with radiation therapy were imaged again after I-125 plaque brachytherapy at 6 and 18 months. Main Outcome Measures OCT and OCTA images, qualitative evaluation of iris and tumor vasculature and quantitative vessel density. Results One eye each of eight normal volunteers and nine patients with iris melanomas or benign iris lesions including freckles, nevi, and an iris pigment epithelial (IPE) cyst were imaged. The normal iris has radially-oriented vessels within the stroma on OCTA. Penetration of flow signal in normal iris depended on iris color, with best penetration seen in light to moderately pigmented irides. Iris melanomas demonstrated tortuous and disorganized intratumoral vasculature. In two eyes with nevi there was no increased vascularity; in another, fine vascular loops were noted near an area of ectropion uveae. Iris freckles and the IPE cyst did not have intrinsic vascularity. The vessel density was significantly higher within iris melanomas (34.5%±9.8%, p<0.05) than in benign iris nevi (8.0%±1.4%) or normal irides (8.0%±1.2%). Tumor regression after radiation therapy for melanomas was associated with decreased vessel density. OCTA at 1050 nm provided better visualization of tumor vasculature and penetration through thicker tumors than at 840 nm. But in very thick tumors and highly pigmented lesions even 1050 nm OCTA could not visualize their full thickness. Interpretable OCTA images were obtained in 82% participants in whom imaging was attempted. Conclusions This is the first demonstration of OCTA in iris tumors. OCTA may provide a dye-free, no-injection, cost-effective method for monitoring a variety of tumors including iris melanocytic lesions for growth and vascularity. This could be helpful in evaluating tumors for malignant transformation and response to treatment. Penetration of the OCT beam remains a limitation for highly pigmented tumors, as does the inability to image the entire iris in a single field. PMID:27856029

  19. Optical Coherence Tomography Angiography Characteristics of Iris Melanocytic Tumors.

    PubMed

    Skalet, Alison H; Li, Yan; Lu, Chen D; Jia, Yali; Lee, ByungKun; Husvogt, Lennart; Maier, Andreas; Fujimoto, James G; Thomas, Charles R; Huang, David

    2017-02-01

    To evaluate tumor vasculature with optical coherence tomography angiography (OCTA) in malignant iris melanomas and benign iris lesions. Cross-sectional observational clinical study. Patients with iris lesions and healthy volunteers. Eyes were imaged using OCTA systems operating at 1050- and 840-nm wavelengths. Three-dimensional OCTA scans were acquired. Iris melanoma patients treated with radiation therapy were imaged again after I-125 plaque brachytherapy at 6 and 18 months. OCT and OCTA images, qualitative evaluation of iris and tumor vasculature, and quantitative vessel density. One eye each of 8 normal volunteers and 9 patients with iris melanomas or benign iris lesions, including freckles, nevi, and an iris pigment epithelial (IPE) cyst, were imaged. The normal iris has radially oriented vessels within the stroma on OCTA. Penetration of flow signal in normal iris depended on iris color, with best penetration seen in light to moderately pigmented irides. Iris melanomas demonstrated tortuous and disorganized intratumoral vasculature. In 2 eyes with nevi there was no increased vascularity; in another, fine vascular loops were noted near an area of ectropion uveae. Iris freckles and the IPE cyst did not have intrinsic vascularity. The vessel density was significantly higher within iris melanomas (34.5%±9.8%, P < 0.05) than in benign iris nevi (8.0%±1.4%) or normal irides (8.0%±1.2%). Tumor regression after radiation therapy for melanomas was associated with decreased vessel density. OCTA at 1050 nm provided better visualization of tumor vasculature and penetration through thicker tumors than at 840 nm. But in very thick tumors and highly pigmented lesions even 1050-nm OCTA could not visualize their full thickness. Interpretable OCTA images were obtained in 82% of participants in whom imaging was attempted. This is the first demonstration of OCTA in iris tumors. OCTA may provide a dye-free, no-injection, cost-effective method for monitoring a variety of tumors, including iris melanocytic lesions, for growth and vascularity. This could be helpful in evaluating tumors for malignant transformation and response to treatment. Penetration of the OCT beam remains a limitation for highly pigmented tumors, as does the inability to image the entire iris in a single field. Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  20. Improved Iris Recognition through Fusion of Hamming Distance and Fragile Bit Distance.

    PubMed

    Hollingsworth, Karen P; Bowyer, Kevin W; Flynn, Patrick J

    2011-12-01

    The most common iris biometric algorithm represents the texture of an iris using a binary iris code. Not all bits in an iris code are equally consistent. A bit is deemed fragile if its value changes across iris codes created from different images of the same iris. Previous research has shown that iris recognition performance can be improved by masking these fragile bits. Rather than ignoring fragile bits completely, we consider what beneficial information can be obtained from the fragile bits. We find that the locations of fragile bits tend to be consistent across different iris codes of the same eye. We present a metric, called the fragile bit distance, which quantitatively measures the coincidence of the fragile bit patterns in two iris codes. We find that score fusion of fragile bit distance and Hamming distance works better for recognition than Hamming distance alone. To our knowledge, this is the first and only work to use the coincidence of fragile bit locations to improve the accuracy of matches.

  1. A young Botswana patient with congenital iris ectropion uvea.

    PubMed

    Shifa, Jemal Zeberga; Nkomazana, Othokawa; Bekele, Negussie Alula; Kassa, Mamo Woldu

    2016-01-01

    Congenital iris ectropion is a rare condition; non-progressive anomaly characterised by the presence of iris pigment epithelium on the anterior surface of the iris stroma and is frequently associated with anterior iris insertion, dysgenesis of the drainage angle and glaucoma. This paper describes unusual case of bilateral case of congenital iris ectropion in adult patient with pupillary abnormality, normal anterior chamber angle structure and with no evidence of glaucoma.

  2. Relationship of the Van Herick Grading System with Peripheral Iris Configuration and Level of Iris Insertion.

    PubMed

    Khan, Faisal Aziz; Niazi, Shafaq Pervez Khan; Khan, Assad Zaman

    2017-09-01

    To determine the relationship of the van Herick angle grading system with the level of iris insertion and peripheral iris configuration. Observational study. Eye department, Combined Military Hospital, Malir Cantt., Karachi, from May to October 2015. Sixty-five eyes of 65 patients were recruited. Anterior chamber depth at the temporal limbus was measured as a fraction of corneal section thickness using van Herick technique and graded on the standard 4-point scale of the van Herick grading system. Gonioscopy of the temporal quadrant was performed with a Posner 4 mirror goniolens and both the true level of iris insertion and peripheral iris configuration were recorded on a 4-point scale so as to equate with the van Herick 4-point grading system. Spearman's rho test was applied to determine the relationship of the van Herick grading system with level of iris root insertion and peripheral iris configuration. Amoderate positive correlation between van Herick grade and peripheral iris configuration was found which was statistically significant (rs=0.42, p < 0.001). Astatistically significant and moderate positive correlation was also detected between van Herick grade and the level of iris insertion (rs=0.45, p < 0.001). The van Herick grade has a moderately positive relationship with the peripheral iris configuration and true level of iris insertion.

  3. Noisy Ocular Recognition Based on Three Convolutional Neural Networks.

    PubMed

    Lee, Min Beom; Hong, Hyung Gil; Park, Kang Ryoung

    2017-12-17

    In recent years, the iris recognition system has been gaining increasing acceptance for applications such as access control and smartphone security. When the images of the iris are obtained under unconstrained conditions, an issue of undermined quality is caused by optical and motion blur, off-angle view (the user's eyes looking somewhere else, not into the front of the camera), specular reflection (SR) and other factors. Such noisy iris images increase intra-individual variations and, as a result, reduce the accuracy of iris recognition. A typical iris recognition system requires a near-infrared (NIR) illuminator along with an NIR camera, which are larger and more expensive than fingerprint recognition equipment. Hence, many studies have proposed methods of using iris images captured by a visible light camera without the need for an additional illuminator. In this research, we propose a new recognition method for noisy iris and ocular images by using one iris and two periocular regions, based on three convolutional neural networks (CNNs). Experiments were conducted by using the noisy iris challenge evaluation-part II (NICE.II) training dataset (selected from the university of Beira iris (UBIRIS).v2 database), mobile iris challenge evaluation (MICHE) database, and institute of automation of Chinese academy of sciences (CASIA)-Iris-Distance database. As a result, the method proposed by this study outperformed previous methods.

  4. Monocyte Phenotype and IFN-γ-Inducible Cytokine Responses Are Associated with Cryptococcal Immune Reconstitution Inflammatory Syndrome

    PubMed Central

    Meya, David B.; Okurut, Samuel; Zziwa, Godfrey; Cose, Stephen; Bohjanen, Paul R.; Mayanja-Kizza, Harriet; Joloba, Moses; Boulware, David R.; Yukari Manabe, Carol; Wahl, Sharon; Janoff, Edward N.

    2017-01-01

    A third of adults with AIDS and cryptococcal meningitis (CM) develop immune reconstitution inflammatory syndrome (IRIS) after initiating antiretroviral therapy (ART), which is thought to result from exaggerated inflammatory antigen-specific T cell responses. The contribution of monocytes to the immunopathogenesis of cryptococcal IRIS remains unclear. We compared monocyte subset frequencies and immune responses in HIV-infected Ugandans at time of CM diagnosis (IRIS-Baseline) for those who later developed CM-IRIS, controls who did not develop CM-IRIS (Control-Baseline) at CM-IRIS (IRIS-Event), and for controls at a time point matched for ART duration (Control-Event) to understand the association of monocyte distribution and immune responses with cryptococcal IRIS. At baseline, stimulation with IFN-γ ex vivo induced a higher frequency of TNF-α- and IL-6-producing monocytes among those who later developed IRIS. Among participants who developed IRIS, ex vivo IFN-γ stimulation induced higher frequencies of activated monocytes, IL-6+, TNF-α+ classical, and IL-6+ intermediate monocytes compared with controls. In conclusion, we have demonstrated that monocyte subset phenotype and cytokine responses prior to ART are associated with and may be predictive of CM-IRIS. Larger studies to further delineate innate immunological responses and the efficacy of immunomodulatory therapies during cryptococcal IRIS are warranted. PMID:29371546

  5. IRIS TOXICOLOGICAL REVIEW AND SUMMARY DOCUMENTS FOR 2-HEXANONE

    EPA Science Inventory

    EPA will conduct an assessment of the noncancer health effects of 2-hexanone. The IRIS program will prepare an IRIS assessment for 2-hexanone. The IRIS assessment for 2-hexanone will consist of a Toxicological Review and an IRIS Summary. The Toxicological Review is a critical ...

  6. CONTINUUM ENHANCEMENTS IN THE ULTRAVIOLET, THE VISIBLE AND THE INFRARED DURING THE X1 FLARE ON 2014 MARCH 29

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

    Kleint, Lucia; Krucker, Säm; Heinzel, Petr

    2016-01-10

    Enhanced continuum brightness is observed in many flares (“white light flares”), yet it is still unclear which processes contribute to the emission. To understand the transport of energy needed to account for this emission, we must first identify both the emission processes and the emission source regions. Possibilities include heating in the chromosphere causing optically thin or thick emission from free-bound transitions of Hydrogen, and heating of the photosphere causing enhanced H{sup −} continuum brightness. To investigate these possibilities, we combine observations from Interface Region Imaging Spectrograph (IRIS), SDO/Helioseismic and Magnetic Imager, and the ground-based Facility Infrared Spectrometer instrument, coveringmore » wavelengths in the far-UV, near-UV (NUV), visible, and infrared during the X1 flare SOL20140329T17:48. Fits of blackbody spectra to infrared and visible wavelengths are reasonable, yielding radiation temperatures ∼6000–6300 K. The NUV emission, formed in the upper photosphere under undisturbed conditions, exceeds these simple fits during the flare, requiring extra emission from the Balmer continuum in the chromosphere. Thus, the continuum originates from enhanced radiation from photosphere (visible-IR) and chromosphere (NUV). From the standard thick-target flare model, we calculate the energy of the nonthermal electrons observed by Reuven Ramaty High Energy Solar Spectroscope Imager (RHESSI) and compare it to the energy radiated by the continuum emission. We find that the energy contained in most electrons >40 keV, or alternatively, of ∼10%–20% of electrons >20 keV is sufficient to explain the extra continuum emission of ∼(4–8) × 10{sup 10} erg s{sup −1} cm{sup −2}. Also, from the timing of the RHESSI HXR and the IRIS observations, we conclude that the NUV continuum is emitted nearly instantaneously when HXR emission is observed with a time difference of no more than 15 s.« less

  7. VizieR Online Data Catalog: Double-peaked narrow lines in AGN. II. z<0.1 (Nevin+, 2016)

    NASA Astrophysics Data System (ADS)

    Nevin, R.; Comerford, J.; Muller-Sanchez, F.; Barrows, R.; Cooper, M.

    2017-02-01

    To determine the nature of 71 Type 2 AGNs with double-peaked [OIII] emission lines in SDSS that are at z<0.1 and further characterize their properties, we observe them using two complementary follow-up methods: optical long-slit spectroscopy and Jansky Very Large Array (VLA) radio observations. We use various spectrographs with similar pixel scales (Lick Kast Spectrograph; Palomar Double Spectrograph; MMT Blue Channel Spectrograph; APO Dual Imaging Spectrograph and Keck DEep Imaging Multi-Object Spectrograph. We use a 1200 lines/mm grating for all spectrographs; see table 1. In future work, we will combine our long-slit observations with the VLA data for the full sample of 71 galaxies (O. Muller-Sanchez+ 2016, in preparation). (4 data files).

  8. Presentation Attack Detection for Iris Recognition System Using NIR Camera Sensor

    PubMed Central

    Nguyen, Dat Tien; Baek, Na Rae; Pham, Tuyen Danh; Park, Kang Ryoung

    2018-01-01

    Among biometric recognition systems such as fingerprint, finger-vein, or face, the iris recognition system has proven to be effective for achieving a high recognition accuracy and security level. However, several recent studies have indicated that an iris recognition system can be fooled by using presentation attack images that are recaptured using high-quality printed images or by contact lenses with printed iris patterns. As a result, this potential threat can reduce the security level of an iris recognition system. In this study, we propose a new presentation attack detection (PAD) method for an iris recognition system (iPAD) using a near infrared light (NIR) camera image. To detect presentation attack images, we first localized the iris region of the input iris image using circular edge detection (CED). Based on the result of iris localization, we extracted the image features using deep learning-based and handcrafted-based methods. The input iris images were then classified into real and presentation attack categories using support vector machines (SVM). Through extensive experiments with two public datasets, we show that our proposed method effectively solves the iris recognition presentation attack detection problem and produces detection accuracy superior to previous studies. PMID:29695113

  9. Novel Approaches to Improve Iris Recognition System Performance Based on Local Quality Evaluation and Feature Fusion

    PubMed Central

    2014-01-01

    For building a new iris template, this paper proposes a strategy to fuse different portions of iris based on machine learning method to evaluate local quality of iris. There are three novelties compared to previous work. Firstly, the normalized segmented iris is divided into multitracks and then each track is estimated individually to analyze the recognition accuracy rate (RAR). Secondly, six local quality evaluation parameters are adopted to analyze texture information of each track. Besides, particle swarm optimization (PSO) is employed to get the weights of these evaluation parameters and corresponding weighted coefficients of different tracks. Finally, all tracks' information is fused according to the weights of different tracks. The experimental results based on subsets of three public and one private iris image databases demonstrate three contributions of this paper. (1) Our experimental results prove that partial iris image cannot completely replace the entire iris image for iris recognition system in several ways. (2) The proposed quality evaluation algorithm is a self-adaptive algorithm, and it can automatically optimize the parameters according to iris image samples' own characteristics. (3) Our feature information fusion strategy can effectively improve the performance of iris recognition system. PMID:24693243

  10. Improving iris recognition performance using segmentation, quality enhancement, match score fusion, and indexing.

    PubMed

    Vatsa, Mayank; Singh, Richa; Noore, Afzel

    2008-08-01

    This paper proposes algorithms for iris segmentation, quality enhancement, match score fusion, and indexing to improve both the accuracy and the speed of iris recognition. A curve evolution approach is proposed to effectively segment a nonideal iris image using the modified Mumford-Shah functional. Different enhancement algorithms are concurrently applied on the segmented iris image to produce multiple enhanced versions of the iris image. A support-vector-machine-based learning algorithm selects locally enhanced regions from each globally enhanced image and combines these good-quality regions to create a single high-quality iris image. Two distinct features are extracted from the high-quality iris image. The global textural feature is extracted using the 1-D log polar Gabor transform, and the local topological feature is extracted using Euler numbers. An intelligent fusion algorithm combines the textural and topological matching scores to further improve the iris recognition performance and reduce the false rejection rate, whereas an indexing algorithm enables fast and accurate iris identification. The verification and identification performance of the proposed algorithms is validated and compared with other algorithms using the CASIA Version 3, ICE 2005, and UBIRIS iris databases.

  11. Novel approaches to improve iris recognition system performance based on local quality evaluation and feature fusion.

    PubMed

    Chen, Ying; Liu, Yuanning; Zhu, Xiaodong; Chen, Huiling; He, Fei; Pang, Yutong

    2014-01-01

    For building a new iris template, this paper proposes a strategy to fuse different portions of iris based on machine learning method to evaluate local quality of iris. There are three novelties compared to previous work. Firstly, the normalized segmented iris is divided into multitracks and then each track is estimated individually to analyze the recognition accuracy rate (RAR). Secondly, six local quality evaluation parameters are adopted to analyze texture information of each track. Besides, particle swarm optimization (PSO) is employed to get the weights of these evaluation parameters and corresponding weighted coefficients of different tracks. Finally, all tracks' information is fused according to the weights of different tracks. The experimental results based on subsets of three public and one private iris image databases demonstrate three contributions of this paper. (1) Our experimental results prove that partial iris image cannot completely replace the entire iris image for iris recognition system in several ways. (2) The proposed quality evaluation algorithm is a self-adaptive algorithm, and it can automatically optimize the parameters according to iris image samples' own characteristics. (3) Our feature information fusion strategy can effectively improve the performance of iris recognition system.

  12. Presentation Attack Detection for Iris Recognition System Using NIR Camera Sensor.

    PubMed

    Nguyen, Dat Tien; Baek, Na Rae; Pham, Tuyen Danh; Park, Kang Ryoung

    2018-04-24

    Among biometric recognition systems such as fingerprint, finger-vein, or face, the iris recognition system has proven to be effective for achieving a high recognition accuracy and security level. However, several recent studies have indicated that an iris recognition system can be fooled by using presentation attack images that are recaptured using high-quality printed images or by contact lenses with printed iris patterns. As a result, this potential threat can reduce the security level of an iris recognition system. In this study, we propose a new presentation attack detection (PAD) method for an iris recognition system (iPAD) using a near infrared light (NIR) camera image. To detect presentation attack images, we first localized the iris region of the input iris image using circular edge detection (CED). Based on the result of iris localization, we extracted the image features using deep learning-based and handcrafted-based methods. The input iris images were then classified into real and presentation attack categories using support vector machines (SVM). Through extensive experiments with two public datasets, we show that our proposed method effectively solves the iris recognition presentation attack detection problem and produces detection accuracy superior to previous studies.

  13. IRIS COLOUR CLASSIFICATION SCALES – THEN AND NOW

    PubMed Central

    Grigore, Mariana; Avram, Alina

    2015-01-01

    Eye colour is one of the most obvious phenotypic traits of an individual. Since the first documented classification scale developed in 1843, there have been numerous attempts to classify the iris colour. In the past centuries, iris colour classification scales has had various colour categories and mostly relied on comparison of an individual’s eye with painted glass eyes. Once photography techniques were refined, standard iris photographs replaced painted eyes, but this did not solve the problem of painted/ printed colour variability in time. Early clinical scales were easy to use, but lacked objectivity and were not standardised or statistically tested for reproducibility. The era of automated iris colour classification systems came with the technological development. Spectrophotometry, digital analysis of high-resolution iris images, hyper spectral analysis of the human real iris and the dedicated iris colour analysis software, all accomplished an objective, accurate iris colour classification, but are quite expensive and limited in use to research environment. Iris colour classification systems evolved continuously due to their use in a wide range of studies, especially in the fields of anthropology, epidemiology and genetics. Despite the wide range of the existing scales, up until present there has been no generally accepted iris colour classification scale. PMID:27373112

  14. IRIS COLOUR CLASSIFICATION SCALES--THEN AND NOW.

    PubMed

    Grigore, Mariana; Avram, Alina

    2015-01-01

    Eye colour is one of the most obvious phenotypic traits of an individual. Since the first documented classification scale developed in 1843, there have been numerous attempts to classify the iris colour. In the past centuries, iris colour classification scales has had various colour categories and mostly relied on comparison of an individual's eye with painted glass eyes. Once photography techniques were refined, standard iris photographs replaced painted eyes, but this did not solve the problem of painted/ printed colour variability in time. Early clinical scales were easy to use, but lacked objectivity and were not standardised or statistically tested for reproducibility. The era of automated iris colour classification systems came with the technological development. Spectrophotometry, digital analysis of high-resolution iris images, hyper spectral analysis of the human real iris and the dedicated iris colour analysis software, all accomplished an objective, accurate iris colour classification, but are quite expensive and limited in use to research environment. Iris colour classification systems evolved continuously due to their use in a wide range of studies, especially in the fields of anthropology, epidemiology and genetics. Despite the wide range of the existing scales, up until present there has been no generally accepted iris colour classification scale.

  15. Iris Recognition Using Feature Extraction of Box Counting Fractal Dimension

    NASA Astrophysics Data System (ADS)

    Khotimah, C.; Juniati, D.

    2018-01-01

    Biometrics is a science that is now growing rapidly. Iris recognition is a biometric modality which captures a photo of the eye pattern. The markings of the iris are distinctive that it has been proposed to use as a means of identification, instead of fingerprints. Iris recognition was chosen for identification in this research because every human has a special feature that each individual is different and the iris is protected by the cornea so that it will have a fixed shape. This iris recognition consists of three step: pre-processing of data, feature extraction, and feature matching. Hough transformation is used in the process of pre-processing to locate the iris area and Daugman’s rubber sheet model to normalize the iris data set into rectangular blocks. To find the characteristics of the iris, it was used box counting method to get the fractal dimension value of the iris. Tests carried out by used k-fold cross method with k = 5. In each test used 10 different grade K of K-Nearest Neighbor (KNN). The result of iris recognition was obtained with the best accuracy was 92,63 % for K = 3 value on K-Nearest Neighbor (KNN) method.

  16. Accurate Iris Recognition at a Distance Using Stabilized Iris Encoding and Zernike Moments Phase Features.

    PubMed

    Tan, Chun-Wei; Kumar, Ajay

    2014-07-10

    Accurate iris recognition from the distantly acquired face or eye images requires development of effective strategies which can account for significant variations in the segmented iris image quality. Such variations can be highly correlated with the consistency of encoded iris features and the knowledge that such fragile bits can be exploited to improve matching accuracy. A non-linear approach to simultaneously account for both local consistency of iris bit and also the overall quality of the weight map is proposed. Our approach therefore more effectively penalizes the fragile bits while simultaneously rewarding more consistent bits. In order to achieve more stable characterization of local iris features, a Zernike moment-based phase encoding of iris features is proposed. Such Zernike moments-based phase features are computed from the partially overlapping regions to more effectively accommodate local pixel region variations in the normalized iris images. A joint strategy is adopted to simultaneously extract and combine both the global and localized iris features. The superiority of the proposed iris matching strategy is ascertained by providing comparison with several state-of-the-art iris matching algorithms on three publicly available databases: UBIRIS.v2, FRGC, CASIA.v4-distance. Our experimental results suggest that proposed strategy can achieve significant improvement in iris matching accuracy over those competing approaches in the literature, i.e., average improvement of 54.3%, 32.7% and 42.6% in equal error rates, respectively for UBIRIS.v2, FRGC, CASIA.v4-distance.

  17. A novel iris patterns matching algorithm of weighted polar frequency correlation

    NASA Astrophysics Data System (ADS)

    Zhao, Weijie; Jiang, Linhua

    2014-11-01

    Iris recognition is recognized as one of the most accurate techniques for biometric authentication. In this paper, we present a novel correlation method - Weighted Polar Frequency Correlation(WPFC) - to match and evaluate two iris images, actually it can also be used for evaluating the similarity of any two images. The WPFC method is a novel matching and evaluating method for iris image matching, which is complete different from the conventional methods. For instance, the classical John Daugman's method of iris recognition uses 2D Gabor wavelets to extract features of iris image into a compact bit stream, and then matching two bit streams with hamming distance. Our new method is based on the correlation in the polar coordinate system in frequency domain with regulated weights. The new method is motivated by the observation that the pattern of iris that contains far more information for recognition is fine structure at high frequency other than the gross shapes of iris images. Therefore, we transform iris images into frequency domain and set different weights to frequencies. Then calculate the correlation of two iris images in frequency domain. We evaluate the iris images by summing the discrete correlation values with regulated weights, comparing the value with preset threshold to tell whether these two iris images are captured from the same person or not. Experiments are carried out on both CASIA database and self-obtained images. The results show that our method is functional and reliable. Our method provides a new prospect for iris recognition system.

  18. Immunopathology of immune reconstitution inflammatory syndrome in Whipple's disease.

    PubMed

    Moos, Verena; Feurle, Gerhard E; Schinnerling, Katina; Geelhaar, Anika; Friebel, Julian; Allers, Kristina; Moter, Annette; Kikhney, Judith; Loddenkemper, Christoph; Kühl, Anja A; Erben, Ulrike; Fenollar, Florence; Raoult, Didier; Schneider, Thomas

    2013-03-01

    During antimicrobial treatment of classic Whipple's disease (CWD), the chronic systemic infection with Tropheryma whipplei, immune reconstitution inflammatory syndrome (IRIS), is a serious complication. The aim of our study was to characterize the immunological processes underlying IRIS in CWD. Following the definition of IRIS, we describe histological features of IRIS and immunological parameters of 24 CWD IRIS patients, 189 CWD patients without IRIS, and 89 healthy individuals. T cell reconstitution, Th1 reactivity, and the phenotype of T cells were described in the peripheral blood, and infiltration of CD4(+) T cells and regulatory T cells in the duodenal mucosa was determined. During IRIS, tissues were heavily infiltrated by CD3(+), predominantly CD45RO(+)CD4(+) T cells. In the periphery, initial reduction of CD4(+) cell counts and their reconstitution on treatment was more pronounced in CWD patients with IRIS than in those without IRIS. The ratio of activated and regulatory CD4(+) T cells, nonspecific Th1 reactivity, and the proportion of naive among CD4(+) T cells was high, whereas serum IL-10 was low during IRIS. T. whipplei-specific Th1 reactivity remained suppressed before and after emergence of IRIS. The findings that IRIS in CWD mainly are mediated by nonspecific activation of CD4(+) T cells and that it is not sufficiently counterbalanced by regulatory T cells indicate that flare-up of pathogen-specific immunoreactivity is not instrumental in the pathogenesis of IRIS in CWD.

  19. Incidence and Predictors of Immune Reconstitution Inflammatory Syndrome in a Rural Area of Mozambique

    PubMed Central

    Letang, Emilio; Miró, José M.; Nhampossa, Tacilta; Ayala, Edgar; Gascon, Joaquim; Menéndez, Clara; Alonso, Pedro L.; Naniche, Denise

    2011-01-01

    Background There is limited data on the epidemiology of Immune Reconstitution Inflammatory Syndrome (IRIS) in rural sub-Saharan Africa. A prospective observational cohort study was conducted to assess the incidence, clinical characteristics, outcome and predictors of IRIS in rural Mozambique. Methods One hundred and thirty-six consecutive antiretroviral treatment (ART)-naïve HIV-1-infected patients initiating ART at the Manhiça district hospital were prospectively followed for development of IRIS over 16 months. Survival analysis by Cox regression was performed to identify pre-ART predictors of IRIS development. Results Thirty-six patients developed IRIS [26.5%, incidence rate 3.1 cases/100 persons-month of ART (95% CI 2.2–4.3)]. Median time to IRIS onset was 62 days from ART initiation (IQR 35.5–93.5). Twenty-five cases (69.4%) were “unmasking”, 10 (27.8%) were “paradoxical”, and 1 (2.8%) developed a paradoxical worsening followed by the unmasking of another condition. Systemic OI (OI-IRIS) accounted for 47% (17/36) of IRIS cases, predominantly of KS (8 cases) and TB (6 cases) IRIS. Mucocutaneous IRIS manifestations (MC-IRIS) accounted for 53% (19/36) of IRIS events, mostly tinea (9 cases) and herpes simplex infection (3 cases). Multivariate analysis identified two independent predictors of IRIS development: pre-ART CD4 count <50 cells/µl (HR 2.3, 95% CI 1.19–4.44, p = 0.01) and body mass index (BMI) <18.5 (HR 2.15, 95% CI 1.07–4.3, p = 0.03). The pre-cART proportion of activated T-cells, as well as the immunologic and virologic response to ART were not associated with IRIS development. All patients continued on ART, 7 (19.4%) required hospitalization and there were 3 deaths (8.3%) attributable to IRIS. Conclusions IRIS is common in patients initiating ART in rural Mozambique. Pre-ART CD4 counts and BMI can easily be assessed at ART initiation in rural sub-Saharan Africa to identify patients at high risk of IRIS, for whom close supervision is warranted. PMID:21386993

  20. Effect of iris registration on outcomes of FEMTOLASIK for myopia and myopic astigmatism.

    PubMed

    Ghoreishi, Mohammad; Beni, Zahra Naderi; Beni, Afsaneh Naderi; Kianersi, Farzan

    2017-09-05

    To compare the visual and refractive outcomes after FEMTOLASIK with and without iris registration. In this randomized, prospective, comparative, contralateral eye study, 118 eyes of 59 patients with myopia and myopic astigmatism underwent LASIK using the Femto LDV femtosecond laser (160 µm) and the MEL80 with or without iris registration. For each patient, iris registration FEMTOLASIK was performed on one eye and non-iris registration FEMTOLASIK was performed on the other eye, assigned at random. Patients were evaluated before and 12 months. Uncorrected visual acuity, best-corrected visual acuity, manifest refraction, contrast sensitivity, and higher-order aberrations (HOAs) were evaluated. At 12 months, the mean UDVA was 0.002 ± 0.07 logMAR (20/19) in iris registration eyes and 0.00 ± 0.06 logMAR (20/24) in non-iris registration eyes (P = 0.9). 61% of iris registration eyes and 71.2% of non-iris registration eyes achieved a UDVA of 20/20 or better (P = 0.31); 98.3% of eyes with the iris registration FEMTOLASIK and 94.9% with the non-iris registration FEMTOLASIK were within ±0.50 D from emmetropia (P = 0.71). No statistically significant difference was found in postoperative contrast sensitivity between groups at 3, 6, 12, or 18 cycles/degree (P > 0.05). There was significant increase in total HOA root mean square in two groups. The mean error magnitude of surgically induced astigmatism 12 months postoperatively was -0.33 in iris registration eyes and -0.24 in the non-iris registration eyes (P = 0.36). FEMTOLASIK with and without iris registration provides similar results in myopic and myopic astigmatism patients.

  1. Steatotic livers are susceptible to normothermic ischemia-reperfusion injury from mitochondrial Complex-I dysfunction

    PubMed Central

    Chu, Michael JJ; Premkumar, Rakesh; Hickey, Anthony JR; Jiang, Yannan; Delahunt, Brett; Phillips, Anthony RJ; Bartlett, Adam SJR

    2016-01-01

    AIM: To assess the effects of ischemic preconditioning (IPC, 10-min ischemia/10-min reperfusion) on steatotic liver mitochondrial function after normothermic ischemia-reperfusion injury (IRI). METHODS: Sixty male Sprague-Dawley rats were fed 8-wk with either control chow or high-fat/high-sucrose diet inducing > 60% mixed steatosis. Three groups (n = 10/group) for each dietary state were tested: (1) the IRI group underwent 60 min partial hepatic ischemia and 4 h reperfusion; (2) the IPC group underwent IPC prior to same standard IRI; and (3) sham underwent the same surgery without IRI or IPC. Hepatic mitochondrial function was analyzed by oxygraphs. Mitochondrial Complex-I, Complex-II enzyme activity, serum alanine aminotransferase (ALT), and histological injury were measured. RESULTS: Steatotic-IRI livers had a greater increase in ALT (2476 ± 166 vs 1457 ± 103 IU/L, P < 0.01) and histological injury following IRI compared to the lean liver group. Steatotic-IRI demonstrated lower Complex-I activity at baseline [78.4 ± 2.5 vs 116.4 ± 6.0 nmol/(min.mg protein), P < 0.001] and following IRI [28.0 ± 6.2 vs 104.3 ± 12.6 nmol/(min.mg protein), P < 0.001]. Steatotic-IRI also demonstrated impaired Complex-I function post-IRI compared to the lean liver IRI group. Complex-II activity was unaffected by hepatic steatosis or IRI. Lean liver mitochondrial function was unchanged following IRI. IPC normalized ALT and histological injury in steatotic livers but had no effect on overall steatotic liver mitochondrial function or individual mitochondrial complex enzyme activities. CONCLUSION: Warm IRI impairs steatotic liver Complex-I activity and function. The protective effects of IPC in steatotic livers may not be mediated through mitochondria. PMID:27217699

  2. IRIS Toxicological Review and Summary Documents for N ...

    EPA Pesticide Factsheets

    EPA's assessment of the noncancer health effects and carcinogenic potential of n-hexane was last prepared and added to the IRIS data base in 1990. The IRIS program is updating the IRIS assessment for n-hexane; this update will incorporate health effects information published since the last assessment was prepared as well as new risk assessment methods. The IRIS assessment for n-hexane will consist of a Toxicological Review and IRIS Summary. The Toxicological Review is a critical review of the physicochemical and toxicokinetic properties of the chemical and its toxicity in humans and experimental systems. The assessment will present reference values for noncancer effects of n-hexane (RfD and RfC) and a cancer assessment, where supported by available data. The Toxicological Review and IRIS Summary will be subject to internal peer consultation, Agency review, and external scientific peer review. EPA is undertaking an update of the Integrated Risk Information System (IRIS) health assessment for n-hexane. The outcome of this project is an updated Toxicological Review and IRIS Summary for n-Hexane that will be entered into the IRIS database. IRIS is an EPA data base containing Agency scientific positions on potential adverse human health effects that may result from chronic (or lifetime) exposure to chemicals in the environment. IRIS contains chemical-specific summaries of qualitative and quantitative health information in support of two steps of the risk assessment

  3. A Statistical Analysis of IrisCode and Its Security Implications.

    PubMed

    Kong, Adams Wai-Kin

    2015-03-01

    IrisCode has been used to gather iris data for 430 million people. Because of the huge impact of IrisCode, it is vital that it is completely understood. This paper first studies the relationship between bit probabilities and a mean of iris images (The mean of iris images is defined as the average of independent iris images.) and then uses the Chi-square statistic, the correlation coefficient and a resampling algorithm to detect statistical dependence between bits. The results show that the statistical dependence forms a graph with a sparse and structural adjacency matrix. A comparison of this graph with a graph whose edges are defined by the inner product of the Gabor filters that produce IrisCodes shows that partial statistical dependence is induced by the filters and propagates through the graph. Using this statistical information, the security risk associated with two patented template protection schemes that have been deployed in commercial systems for producing application-specific IrisCodes is analyzed. To retain high identification speed, they use the same key to lock all IrisCodes in a database. The belief has been that if the key is not compromised, the IrisCodes are secure. This study shows that even without the key, application-specific IrisCodes can be unlocked and that the key can be obtained through the statistical dependence detected.

  4. Noisy Ocular Recognition Based on Three Convolutional Neural Networks

    PubMed Central

    Lee, Min Beom; Hong, Hyung Gil; Park, Kang Ryoung

    2017-01-01

    In recent years, the iris recognition system has been gaining increasing acceptance for applications such as access control and smartphone security. When the images of the iris are obtained under unconstrained conditions, an issue of undermined quality is caused by optical and motion blur, off-angle view (the user’s eyes looking somewhere else, not into the front of the camera), specular reflection (SR) and other factors. Such noisy iris images increase intra-individual variations and, as a result, reduce the accuracy of iris recognition. A typical iris recognition system requires a near-infrared (NIR) illuminator along with an NIR camera, which are larger and more expensive than fingerprint recognition equipment. Hence, many studies have proposed methods of using iris images captured by a visible light camera without the need for an additional illuminator. In this research, we propose a new recognition method for noisy iris and ocular images by using one iris and two periocular regions, based on three convolutional neural networks (CNNs). Experiments were conducted by using the noisy iris challenge evaluation-part II (NICE.II) training dataset (selected from the university of Beira iris (UBIRIS).v2 database), mobile iris challenge evaluation (MICHE) database, and institute of automation of Chinese academy of sciences (CASIA)-Iris-Distance database. As a result, the method proposed by this study outperformed previous methods. PMID:29258217

  5. IRIS TOXICOLOGICAL REVIEW AND SUMMARY DOCUMENTS FOR 1,1,1-TRICHLOROETHANE (PEER REVIEW PLAN)

    EPA Science Inventory

    EPA's assessment of the carcinogenic potential of 1,1,1-trichloroethane was entered into the IRIS database in 1988, and the assessment of noncancer effects following oral exposure was withdrawn from IRIS in 1991. The IRIS program prepared an update of the IRIS assessment for 1,1,...

  6. Iris double recognition based on modified evolutionary neural network

    NASA Astrophysics Data System (ADS)

    Liu, Shuai; Liu, Yuan-Ning; Zhu, Xiao-Dong; Huo, Guang; Liu, Wen-Tao; Feng, Jia-Kai

    2017-11-01

    Aiming at multicategory iris recognition under illumination and noise interference, this paper proposes a method of iris double recognition based on a modified evolutionary neural network. An equalization histogram and Laplace of Gaussian operator are used to process the iris to suppress illumination and noise interference and Haar wavelet to convert the iris feature to binary feature encoding. Calculate the Hamming distance for the test iris and template iris , and compare with classification threshold, determine the type of iris. If the iris cannot be identified as a different type, there needs to be a secondary recognition. The connection weights in back-propagation (BP) neural network use modified evolutionary neural network to adaptively train. The modified neural network is composed of particle swarm optimization with mutation operator and BP neural network. According to different iris libraries in different circumstances of experimental results, under illumination and noise interference, the correct recognition rate of this algorithm is higher, the ROC curve is closer to the coordinate axis, the training and recognition time is shorter, and the stability and the robustness are better.

  7. Ordinal measures for iris recognition.

    PubMed

    Sun, Zhenan; Tan, Tieniu

    2009-12-01

    Images of a human iris contain rich texture information useful for identity authentication. A key and still open issue in iris recognition is how best to represent such textural information using a compact set of features (iris features). In this paper, we propose using ordinal measures for iris feature representation with the objective of characterizing qualitative relationships between iris regions rather than precise measurements of iris image structures. Such a representation may lose some image-specific information, but it achieves a good trade-off between distinctiveness and robustness. We show that ordinal measures are intrinsic features of iris patterns and largely invariant to illumination changes. Moreover, compactness and low computational complexity of ordinal measures enable highly efficient iris recognition. Ordinal measures are a general concept useful for image analysis and many variants can be derived for ordinal feature extraction. In this paper, we develop multilobe differential filters to compute ordinal measures with flexible intralobe and interlobe parameters such as location, scale, orientation, and distance. Experimental results on three public iris image databases demonstrate the effectiveness of the proposed ordinal feature models.

  8. Multiple local feature representations and their fusion based on an SVR model for iris recognition using optimized Gabor filters

    NASA Astrophysics Data System (ADS)

    He, Fei; Liu, Yuanning; Zhu, Xiaodong; Huang, Chun; Han, Ye; Dong, Hongxing

    2014-12-01

    Gabor descriptors have been widely used in iris texture representations. However, fixed basic Gabor functions cannot match the changing nature of diverse iris datasets. Furthermore, a single form of iris feature cannot overcome difficulties in iris recognition, such as illumination variations, environmental conditions, and device variations. This paper provides multiple local feature representations and their fusion scheme based on a support vector regression (SVR) model for iris recognition using optimized Gabor filters. In our iris system, a particle swarm optimization (PSO)- and a Boolean particle swarm optimization (BPSO)-based algorithm is proposed to provide suitable Gabor filters for each involved test dataset without predefinition or manual modulation. Several comparative experiments on JLUBR-IRIS, CASIA-I, and CASIA-V4-Interval iris datasets are conducted, and the results show that our work can generate improved local Gabor features by using optimized Gabor filters for each dataset. In addition, our SVR fusion strategy may make full use of their discriminative ability to improve accuracy and reliability. Other comparative experiments show that our approach may outperform other popular iris systems.

  9. SmallSat Spinning Lander with a Raman Spectrometer Payload for Future Ocean Worlds Exploration Missions

    NASA Technical Reports Server (NTRS)

    Ridenoure, R.; Angel, S. M.; Aslam, S.; Gorius, N.; Hewagama, T.; Nixon, C. A.; Sharma, S.

    2017-01-01

    We describe an Evolved Expendable Launch Vehicle Secondary Payload Adapter (ESPA)-class SmallSat spinning lander concept for the exploration of Europa or other Ocean World surfaces to ascertain the potential for life. The spinning lander will be ejected from an ESPA ring from an orbiting or flyby spacecraft and will carry on-board a standoff remote Spatial Heterodyne Raman spectrometer (SHRS) and a time resolved laser induced fluorescence spectrograph (TR-LIFS), and once landed and stationary the instruments will make surface chemical measurements. The SHRS and TR-LIFS have no moving parts have minimal mass and power requirements and will be able to characterize the surface and near-surface chemistry, including complex organic chemistry to constrain the ocean composition.

  10. SmallSat Spinning Lander with a Raman Spectrometer Payload for Future Ocean Worlds Exploration Missions

    NASA Astrophysics Data System (ADS)

    Ridenoure, R.; Angel, S. M.; Aslam, S.; Gorius, N.; Hewagama, T.; Nixon, C. A.; Sharma, S.

    2017-09-01

    We describe an Evolved Expendable Launch Vehicle Secondary Payload Adapter (ESPA)-class SmallSat spinning lander concept for the exploration of Europa or other Ocean World surfaces to ascertain the potential for life. The spinning lander will be ejected from an ESPA ring from an orbiting or flyby spacecraft and will carry on-board a standoff remote Spatial Heterodyne Raman spectrometer (SHRS) and a time resolved laser induced fluorescence spectrograph (TR-LIFS), and once landed and stationary the instruments will make surface chemical measurements. The SHRS and TR-LIFS have no moving parts have minimal mass and power requirements and will be able to characterize the surface and near-surface chemistry, including complex organic chemistry to constrain the ocean composition.

  11. How to align a new detector and micro shutter inside JWST's Near Infrared Spectrograph (NIRSpec)

    NASA Astrophysics Data System (ADS)

    te Plate, Maurice; Rumler, Peter; Jensen, Peter; Eder, Robert; Ehrenwinkler, Ralf; Merkle, Frank; Roedel, Andreas; Speckmaier, Max; Johnson, Thomas E.; Mott, Brent; Snodgrass, Stephen; Gunn, Chris; Ward, Justin

    2016-09-01

    JWST will be the biggest space telescope ever built and it will lead to astounding scientific breakthroughs. The mission will be launched in October 2018 from Kourou, French Guyana by an ESA provided Ariane 5 rocket. NIRSpec, one of the four instruments on board of the mission, recently underwent a major upgrade. New infrared detectors were installed and the Micro Shutter Assembly (MSA) was replaced as well. The rework was necessary because both systems were found to be degrading beyond a level that could be accepted. The installation and "in situ" alignment of these new systems required special techniques and alignment jigs that will be described in this paper. Some first results will be presented as well.

  12. Relativistic Astronomy

    NASA Astrophysics Data System (ADS)

    Zhang, Bing; Li, Kunyang

    2018-02-01

    The “Breakthrough Starshot” aims at sending near-speed-of-light cameras to nearby stellar systems in the future. Due to the relativistic effects, a transrelativistic camera naturally serves as a spectrograph, a lens, and a wide-field camera. We demonstrate this through a simulation of the optical-band image of the nearby galaxy M51 in the rest frame of the transrelativistic camera. We suggest that observing celestial objects using a transrelativistic camera may allow one to study the astronomical objects in a special way, and to perform unique tests on the principles of special relativity. We outline several examples that suggest transrelativistic cameras may make important contributions to astrophysics and suggest that the Breakthrough Starshot cameras may be launched in any direction to serve as a unique astronomical observatory.

  13. Effects of Iris Surface Curvature on Iris Recognition

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

    Thompson, Joseph T; Flynn, Patrick J; Bowyer, Kevin W

    To focus on objects at various distances, the lens of the eye must change shape to adjust its refractive power. This change in lens shape causes a change in the shape of the iris surface which can be measured by examining the curvature of the iris. This work isolates the variable of iris curvature in the recognition process and shows that differences in iris curvature degrade matching ability. To our knowledge, no other work has examined the effects of varying iris curvature on matching ability. To examine this degradation, we conduct a matching experiment across pairs of images with varyingmore » degrees of iris curvature differences. The results show a statistically signi cant degradation in matching ability. Finally, the real world impact of these ndings is discussed« less

  14. IRIS Toxicological Review of Benzo[a]pyrene (Interagency ...

    EPA Pesticide Factsheets

    In January 2017, EPA finalized the IRIS assessment of Benzo[a]pyrene. The Toxicological Review was reviewed internally by EPA and by other federal agencies and White House Offices before public release. Consistent with the May 2009 IRIS assessment development process, all written comments on IRIS assessments submitted by other federal agencies and White House Offices are made publicly available. Accordingly, interagency comments and the interagency science discussion materials provided to other agencies, including interagency review drafts of the IRIS Toxicological Review of Benzo[a]pyrene are posted on this site. EPA is undertaking an update of the Integrated Risk Information System (IRIS) health assessment for benzo[a]pyrene (BaP). The outcome of this project is an updated Toxicological Review and IRIS Summary for BaP that will be entered into the IRIS database.

  15. IrisDenseNet: Robust Iris Segmentation Using Densely Connected Fully Convolutional Networks in the Images by Visible Light and Near-Infrared Light Camera Sensors

    PubMed Central

    Arsalan, Muhammad; Naqvi, Rizwan Ali; Kim, Dong Seop; Nguyen, Phong Ha; Owais, Muhammad; Park, Kang Ryoung

    2018-01-01

    The recent advancements in computer vision have opened new horizons for deploying biometric recognition algorithms in mobile and handheld devices. Similarly, iris recognition is now much needed in unconstraint scenarios with accuracy. These environments make the acquired iris image exhibit occlusion, low resolution, blur, unusual glint, ghost effect, and off-angles. The prevailing segmentation algorithms cannot cope with these constraints. In addition, owing to the unavailability of near-infrared (NIR) light, iris recognition in visible light environment makes the iris segmentation challenging with the noise of visible light. Deep learning with convolutional neural networks (CNN) has brought a considerable breakthrough in various applications. To address the iris segmentation issues in challenging situations by visible light and near-infrared light camera sensors, this paper proposes a densely connected fully convolutional network (IrisDenseNet), which can determine the true iris boundary even with inferior-quality images by using better information gradient flow between the dense blocks. In the experiments conducted, five datasets of visible light and NIR environments were used. For visible light environment, noisy iris challenge evaluation part-II (NICE-II selected from UBIRIS.v2 database) and mobile iris challenge evaluation (MICHE-I) datasets were used. For NIR environment, the institute of automation, Chinese academy of sciences (CASIA) v4.0 interval, CASIA v4.0 distance, and IIT Delhi v1.0 iris datasets were used. Experimental results showed the optimal segmentation of the proposed IrisDenseNet and its excellent performance over existing algorithms for all five datasets. PMID:29748495

  16. IrisDenseNet: Robust Iris Segmentation Using Densely Connected Fully Convolutional Networks in the Images by Visible Light and Near-Infrared Light Camera Sensors.

    PubMed

    Arsalan, Muhammad; Naqvi, Rizwan Ali; Kim, Dong Seop; Nguyen, Phong Ha; Owais, Muhammad; Park, Kang Ryoung

    2018-05-10

    The recent advancements in computer vision have opened new horizons for deploying biometric recognition algorithms in mobile and handheld devices. Similarly, iris recognition is now much needed in unconstraint scenarios with accuracy. These environments make the acquired iris image exhibit occlusion, low resolution, blur, unusual glint, ghost effect, and off-angles. The prevailing segmentation algorithms cannot cope with these constraints. In addition, owing to the unavailability of near-infrared (NIR) light, iris recognition in visible light environment makes the iris segmentation challenging with the noise of visible light. Deep learning with convolutional neural networks (CNN) has brought a considerable breakthrough in various applications. To address the iris segmentation issues in challenging situations by visible light and near-infrared light camera sensors, this paper proposes a densely connected fully convolutional network (IrisDenseNet), which can determine the true iris boundary even with inferior-quality images by using better information gradient flow between the dense blocks. In the experiments conducted, five datasets of visible light and NIR environments were used. For visible light environment, noisy iris challenge evaluation part-II (NICE-II selected from UBIRIS.v2 database) and mobile iris challenge evaluation (MICHE-I) datasets were used. For NIR environment, the institute of automation, Chinese academy of sciences (CASIA) v4.0 interval, CASIA v4.0 distance, and IIT Delhi v1.0 iris datasets were used. Experimental results showed the optimal segmentation of the proposed IrisDenseNet and its excellent performance over existing algorithms for all five datasets.

  17. The International Reference Ionosphere Today and in the Future

    NASA Technical Reports Server (NTRS)

    Bilitza, Dieter; McKinnell, Lee-Ane; Reinisch, Bodo; Fuller-Rowell,Tim

    2010-01-01

    The international reference ionosphere (IRI) is the internationally recognized and recommended standard for the specification of plasma parameters in Earth's ionosphere. It describes monthly averages of electron density, electron temperature, ion temperature, ion composition, and several additional parameters in the altitude range from 60 to 1,500 km. A joint working group of the Committee on Space Research (COSPAR) and the International Union of Radio Science (URSI) is in charge of developing and improving the IRI model. As requested by COSPAR and URSI, IRI is an empirical model being based on most of the available and reliable data sources for the ionospheric plasma. The paper describes the latest version of the model and reviews efforts towards future improvements, including the development of new global models for the F2 peak density and height, and a new approach to describe the electron density in the topside and plasmasphere. Our emphasis will be on the electron density because it is the IRI parameter most relevant to geodetic techniques and studies. Annual IRI meetings are the main venue for the discussion of IRI activities, future improvements, and additions to the model. A new special IRI task force activity is focusing on the development of a real-time IRI (RT-IRI) by combining data assimilation techniques with the IRI model. A first RT-IRI task force meeting was held in 2009 in Colorado Springs. We will review the outcome of this meeting and the plans for the future. The IRI homepage is at http://www.IRI.gsfc.nasa.gov

  18. Lattice-like collagen fiber meshwork in the iris stroma of the cat: a possible mechanism to generate the tension directed towards the iris root which is required for pupillary dilatation in the sympathectomized eye.

    PubMed

    Sakuraba, M; Yun, S; Ichinohe, N; Yonekura, H; Shoumura, K

    1999-10-01

    NaOH digestion technique for collagen fiber dissection and scanning electron microscopy demonstrated a lattice-like meshwork in the anterior surface of the iris stroma of the cat. The mesh threads were made of collagen fibril bundles. In the constricted pupil, the meshes were square to rhomboid with the diagonals in the direction of the radius or circumference of the iris. In the dilated pupil, however, the meshes were strongly flattened rhomboid or ellipse with a longer diagnoal or axis in the circumferential direction. At the mesh corners facing the pupillary margin or the iris root, the collagen fibril bundles were strongly bent in the iris of the constricted pupil, while they were almost straight or slightly wavy in the iris of the dilated pupil. Accumulation of elasticity tension generated by this small distortion of the iris-mesh threads in the constricted pupil was considered to generate a tension directed towards the iris root, which is required for pupillary dilatation in the sympathectomized eye. On the posterior surface of the iris stroma, numerous thin pleats tightly woven with collagen fibrils traversed straightway through the radial length of the ciliary zone of the iris in both constricted and dilated pupils. The structural changes of these pleats in miosis and mydriasis were very small compared with the meshwork of the anterior aspect of the iris. Therefore, they were considered to work mainly as an iris skeleton.

  19. IRIS Toxicological Review of Hexahydro-1,3,5-Trinitro-1,3,5 ...

    EPA Pesticide Factsheets

    EPA is developing an Integrated Risk Information System (IRIS) assessment of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and has released the draft assessment for public comment. When final, the assessment will appear on the IRIS database. EPA is undertaking an update of the Integrated Risk Information System (IRIS) health assessment for RDX. The outcome of this project is an updated Toxicological Review and IRIS Summary for RDX that will be entered into the IRIS database.

  20. IRIS Toxicological Review of Benzo[a]pyrene (Public ...

    EPA Pesticide Factsheets

    EPA is developing an Integrated Risk Information System (IRIS) assessment of benzo[a]pyrene and has released the draft assessment for public comment and external peer review. When final, the assessment will appear on the IRIS database. EPA is undertaking an update of the Integrated Risk Information System (IRIS) health assessment for benzo[a]pyrene (BaP). The outcome of this project is an updated Toxicological Review and IRIS Summary for BaP that will be entered into the IRIS database.

  1. A novel iris localization algorithm using correlation filtering

    NASA Astrophysics Data System (ADS)

    Pohit, Mausumi; Sharma, Jitu

    2015-06-01

    Fast and efficient segmentation of iris from the eye images is a primary requirement for robust database independent iris recognition. In this paper we have presented a new algorithm for computing the inner and outer boundaries of the iris and locating the pupil centre. Pupil-iris boundary computation is based on correlation filtering approach, whereas iris-sclera boundary is determined through one dimensional intensity mapping. The proposed approach is computationally less extensive when compared with the existing algorithms like Hough transform.

  2. IRIS Toxicological Review of Tert-Butyl Alcohol (Tert-Butanol) ...

    EPA Pesticide Factsheets

    On April 29, 2016, the Toxicological Review of tert-Butyl Alcohol (tert-Butanol) (Public Comment Draft) was released for public comment. The draft Toxicological Review and charge were reviewed internally by EPA and by other federal agencies and the Executive Office of the President during Step 3 (Interagency Science Consultation) before public release. As part of the IRIS process, all written interagency comments on IRIS assessments will be made publicly available. Accordingly, interagency comments with EPA's response and the interagency science consultation drafts of the IRIS Toxicological Review of tert-Butanol and charge to external peer reviewers are posted on this site. EPA is undertaking a new health assessment for t-butyl alcohol (tert-butanol) for the Integrated Risk Information System (IRIS). The outcome of this project will be a Toxicological Review and IRIS and IRIS Summary of TBA that will be entered on the IRIS database. IRIS is an EPA database containing Agency scientific positions on potential adverse human health effects that may result from chronic (or lifetime) exposure to chemicals in the environment. IRIS contains chemical-specific summaries of qualitative and quantitative health information to evaluate potential public health risks associated with environmental contaminants. The IRIS database is relied on for the development of risk assessments, site-specific environmental decisions, and rule making.

  3. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (Etbe) ...

    EPA Pesticide Factsheets

    In September 2016, EPA released the draft IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) for public comment and discussion. The draft assessment was reviewed internally by EPA and by other federal agencies and White House Offices before public release. Consistent with the May 2009 IRIS assessment development process, all written comments on IRIS assessments submitted by other federal agencies and White House Offices are made publicly available. Accordingly, interagency comments and the interagency science consultation materials provided to other agencies, including interagency review drafts of the IRIS Toxicological Review of Ethyl Tertiary Butyl Ether are posted on this site. EPA is undertaking an new health assessment for ethyl tertiary butyl ether (ETBE) for the Integrated Risk Information System (IRIS). The outcome of this project will be a Toxicological Review and IRIS Summary of ETBE that will be entered on the IRIS database. IRIS is an EPA database containing Agency scientific positions on potential adverse human health effects that may result from chronic (or lifetime) exposure to chemicals in the environment. IRIS contains chemical-specific summaries of qualitative and quantitative health information in support of two steps of the risk assessment process, i.e., hazard identification and dose-response evaluation. IRIS assessments are used nationally and internationally in combination with specific situational exposure assessment infor

  4. IRIS Toxicological Review of Biphenyl (Interagency Science ...

    EPA Pesticide Factsheets

    On September 30, 2011, the draft Toxicological Review of Biphenyl and the charge to external peer reviewers were released for external peer review and public comment. The Toxicological Review and charge were reviewed internally by EPA and by other federal agencies and White House Offices before public release. In the new IRIS process (May 2009), introduced by the EPA Administrator, all written comments on IRIS assessments submitted by other federal agencies and White House Offices will be made publicly available. Accordingly, interagency comments and the interagency science consultation draft of the IRIS Toxicological Review of Biphenyl and the charge to external peer reviewers are posted on this site. EPA is undertaking a new health assessment for biphenyl for the Integrated Risk Information System (IRIS). The outcome of this project will be a Toxicological Review and IRIS and IRIS Summary of biohenyl that will be entered on the IRIS database. IRIS is an EPA database containing Agency scientific positions on potential adverse human health effects that may result from chronic (or lifetime) exposure to chemicals in the environment. IRIS contains chemical-specific summaries of qualitative and quantitative health information to evaluate potential public health risks associated with exposure assessment information to evaluate potential public health risks associated with environmental contaminants. The IRIS database is relied on for the development of risk ass

  5. IRIS TOXICOLOGICAL REVIEW AND SUMMARY ...

    EPA Pesticide Factsheets

    EPA's assessment of the noncancer health effects and carcinogenic potential of 1,2,3-trichloropropane (TCP) was added to the IRIS database in 1990. The IRIS program is updating the IRIS assessment for TCP. This update will incorporate health effects information published since the last assessment was prepared as well as new risk assessment methods. The IRIS assessment for TCP will consist of a Toxicological Review and IRIS Summary. The Toxicological Review is a critical review of the physicochemical and toxicokinetic properties of the chemical and its toxicity in humans and experimental systems. The assessment will present reference values for noncancer effects of TCP (RfD and RfC) and a cancer assessment. The Toxicological Review and IRIS Summary will be subject to internal peer consultation, Agency review, and external scientific peer review. The final products will constitute the Agency's opinion on the toxicity of TCP. EPA is undertaking an Integrated Risk Information System (IRIS) health assessment for 1,2,3-trichloropropane. IRIS is an EPA database containing the Agency's consensus scientific positions on potential adverse human effects that may result from chronic (or lifetime) exposure to chemicals in the environment. IRIS contains chemical-specific summaries of qualitative and quantitative health information in support of two steps of the risk assessment process, i.e., hazard identification and dose-response evaluation. IRIS assessments are used in

  6. Matrix metalloproteinases and tissue damage in HIV-tuberculosis immune reconstitution inflammatory syndrome

    PubMed Central

    Tadokera, Rebecca; Meintjes, Graeme A; Wilkinson, Katalin A; Skolimowska, Keira H; Walker, Naomi; Friedland, Jon S; Maartens, Gary; Elkington, Paul T G; Wilkinson, Robert J

    2014-01-01

    The HIV-TB-associated immune reconstitution inflammatory syndrome (TB-IRIS) can complicate combined treatments for HIV-1 and TB. Little is known about tissue damage in TB-IRIS. Matrix metalloproteinases (MMPs) degrade components of the extracellular matrix and consequently may play a role in such immunopathology. Here we investigated the involvement of MMPs in TB-IRIS. We determined MMP transcript abundance and secreted protein in Mycobacterium tuberculosis stimulated PBMCs from 22 TB-IRIS patients and 22 non-IRIS controls. We also measured MMP protein levels in corresponding serum and the effect of prednisone — which reduces the duration of symptoms in IRIS patients — or placebo treatment on MMP transcript and circulating MMP protein levels. PBMCs from TB-IRIS had increased MMP-1,-3,-7, and-10 transcript levels when compared with those of controls at either 6 or 24 h. Similarly, MMP-1,-3,-7, and-10 protein secretion in stimulated cultures was higher in TB-IRIS than in controls. Serum MMP-7 concentration was elevated in TB-IRIS and 2 weeks of corticosteroid therapy decreased this level, although not significantly. TB-IRIS is associated with a distinct pattern of MMP gene and protein activation. Modulation of dysregulated MMP activity may represent a novel therapeutic approach to alleviate TB-IRIS in HIV-TB patients undergoing treatment. PMID:24136296

  7. [Moxiflaxin and iris transillumination].

    PubMed

    Broens, A; Collignon, N

    2016-07-01

    Bilateral Acute Iris Transillumination (BAIT) is a new clinical entity characterized by acute onset of pigment dispersion in the anterior chamber and angle, depigmentation of the iris stroma and permanent iris transillumination, masquerading as uveitis. An association with oral moxifloxacin is reported in some articles. We describe one case of bilateral acute iris transillumination, following the use of systemic moxifloxacin.

  8. Raspberry Shake- A World-Wide Citizen Seismograph Network

    NASA Astrophysics Data System (ADS)

    Christensen, B. C.; Blanco Chia, J. F.

    2017-12-01

    Raspberry Shake was conceived as an inexpensive plug-and-play solution to satisfy the need for universal, quick and accurate earthquake detections. First launched on Kickstarter's crowdfunding platform in July of 2016, the Raspberry Shake project was funded within hours of the launch date and, by the end of the campaign, reached more than 1000% of its initial funding goal. This demonstrated for the first time that there exists a strong interest among Makers, Hobbyists and Do It Yourselfers for personal seismographs. From here, a citizen scientist network was created and it has steadily been growing. The Raspberry Shake network is currently being used in conjunction with publicly available broadband data from the GSN and other state-run seismic networks available through the IRIS, Geoscope and GEOFON data centers to detect and locate earthquakes large and small around the globe. Raspberry Shake looks well positioned to improve local monitoring of earthquakes on a global scale, deepen community's understanding of earthquakes, and serve as a formidable teaching tool. We present the main results of the project, the current state of the network, and the new Raspberry Shake models that are being built.

  9. Design method of ARM based embedded iris recognition system

    NASA Astrophysics Data System (ADS)

    Wang, Yuanbo; He, Yuqing; Hou, Yushi; Liu, Ting

    2008-03-01

    With the advantages of non-invasiveness, uniqueness, stability and low false recognition rate, iris recognition has been successfully applied in many fields. Up to now, most of the iris recognition systems are based on PC. However, a PC is not portable and it needs more power. In this paper, we proposed an embedded iris recognition system based on ARM. Considering the requirements of iris image acquisition and recognition algorithm, we analyzed the design method of the iris image acquisition module, designed the ARM processing module and its peripherals, studied the Linux platform and the recognition algorithm based on this platform, finally actualized the design method of ARM-based iris imaging and recognition system. Experimental results show that the ARM platform we used is fast enough to run the iris recognition algorithm, and the data stream can flow smoothly between the camera and the ARM chip based on the embedded Linux system. It's an effective method of using ARM to actualize portable embedded iris recognition system.

  10. The BigBOSS spectrograph

    NASA Astrophysics Data System (ADS)

    Jelinsky, Patrick; Bebek, Chris; Besuner, Robert; Carton, Pierre-Henri; Edelstein, Jerry; Lampton, Michael; Levi, Michael E.; Poppett, Claire; Prieto, Eric; Schlegel, David; Sholl, Michael

    2012-09-01

    BigBOSS is a proposed ground-based dark energy experiment to study baryon acoustic oscillations (BAO) and the growth of structure with a 14,000 square degree galaxy and quasi-stellar object redshift survey. It consists of a 5,000- fiber-positioner focal plane feeding the spectrographs. The optical fibers are separated into ten 500 fiber slit heads at the entrance of ten identical spectrographs in a thermally insulated room. Each of the ten spectrographs has a spectral resolution (λ/Δλ) between 1500 and 4000 over a wavelength range from 360 - 980 nm. Each spectrograph uses two dichroic beam splitters to separate the spectrograph into three arms. It uses volume phase holographic (VPH) gratings for high efficiency and compactness. Each arm uses a 4096x4096 15 μm pixel charge coupled device (CCD) for the detector. We describe the requirements and current design of the BigBOSS spectrograph. Design trades (e.g. refractive versus reflective) and manufacturability are also discussed.

  11. Human iris three-dimensional imaging at micron resolution by a micro-plenoptic camera

    PubMed Central

    Chen, Hao; Woodward, Maria A.; Burke, David T.; Jeganathan, V. Swetha E.; Demirci, Hakan; Sick, Volker

    2017-01-01

    A micro-plenoptic system was designed to capture the three-dimensional (3D) topography of the anterior iris surface by simple single-shot imaging. Within a depth-of-field of 2.4 mm, depth resolution of 10 µm can be achieved with accuracy (systematic errors) and precision (random errors) below 20%. We demonstrated the application of our micro-plenoptic imaging system on two healthy irides, an iris with naevi, and an iris with melanoma. The ridges and folds, with height differences of 10~80 µm, on the healthy irides can be effectively captured. The front surface on the iris naevi was flat, and the iris melanoma was 50 ± 10 µm higher than the surrounding iris. The micro-plenoptic imaging system has great potential to be utilized for iris disease diagnosis and continuing, simple monitoring. PMID:29082081

  12. Human iris three-dimensional imaging at micron resolution by a micro-plenoptic camera.

    PubMed

    Chen, Hao; Woodward, Maria A; Burke, David T; Jeganathan, V Swetha E; Demirci, Hakan; Sick, Volker

    2017-10-01

    A micro-plenoptic system was designed to capture the three-dimensional (3D) topography of the anterior iris surface by simple single-shot imaging. Within a depth-of-field of 2.4 mm, depth resolution of 10 µm can be achieved with accuracy (systematic errors) and precision (random errors) below 20%. We demonstrated the application of our micro-plenoptic imaging system on two healthy irides, an iris with naevi, and an iris with melanoma. The ridges and folds, with height differences of 10~80 µm, on the healthy irides can be effectively captured. The front surface on the iris naevi was flat, and the iris melanoma was 50 ± 10 µm higher than the surrounding iris. The micro-plenoptic imaging system has great potential to be utilized for iris disease diagnosis and continuing, simple monitoring.

  13. Toward noncooperative iris recognition: a classification approach using multiple signatures.

    PubMed

    Proença, Hugo; Alexandre, Luís A

    2007-04-01

    This paper focuses on noncooperative iris recognition, i.e., the capture of iris images at large distances, under less controlled lighting conditions, and without active participation of the subjects. This increases the probability of capturing very heterogeneous images (regarding focus, contrast, or brightness) and with several noise factors (iris obstructions and reflections). Current iris recognition systems are unable to deal with noisy data and substantially increase their error rates, especially the false rejections, in these conditions. We propose an iris classification method that divides the segmented and normalized iris image into six regions, makes an independent feature extraction and comparison for each region, and combines each of the dissimilarity values through a classification rule. Experiments show a substantial decrease, higher than 40 percent, of the false rejection rates in the recognition of noisy iris images.

  14. Validation of a published case definition for tuberculosis-associated immune reconstitution inflammatory syndrome.

    PubMed

    Haddow, Lewis J; Moosa, Mahomed-Yunus S; Easterbrook, Philippa J

    2010-01-02

    To evaluate the International Network for the Study of HIV-associated IRIS (INSHI) case definitions for tuberculosis (TB)-associated immune reconstitution inflammatory syndrome (IRIS) in a South African cohort. Prospective cohort of 498 adult HIV-infected patients initiating antiretroviral therapy. Patients were followed up for 24 weeks and all clinical events were recorded. Events with TB-IRIS as possible cause were assessed by consensus expert opinion and INSHI case definition. Positive, negative, and chance-corrected agreement (kappa) were calculated, and reasons for disagreement were assessed. One hundred and two (20%) patients were receiving TB therapy at antiretroviral therapy initiation. Three hundred and thirty-three events were evaluated (74 potential paradoxical IRIS, 259 potential unmasking IRIS). Based on expert opinion, there were 18 cases of paradoxical IRIS associated with TB and/or other opportunistic disease. The INSHI criteria for TB-IRIS agreed in 13 paradoxical cases, giving positive agreement of 72.2%, negative agreement in 52/56 non-TB-IRIS events (92.9%), and kappa of 0.66. There were 19 unmasking TB-IRIS cases based on expert opinion, of which 12 were considered IRIS using the INSHI definition (positive agreement 63.2%). There was agreement in all 240 non-TB-IRIS events (negative agreement 100%) and kappa was 0.76. There was good agreement between the INSHI case definition for both paradoxical and unmasking TB-IRIS and consensus expert opinion. These results support the use of this definition in clinical and research practice, with minor caveats in its application.

  15. Engineering a Light-Attenuating Artificial Iris

    PubMed Central

    Shareef, Farah J.; Sun, Shan; Kotecha, Mrignayani; Kassem, Iris; Azar, Dimitri; Cho, Michael

    2016-01-01

    Purpose Discomfort from light exposure leads to photophobia, glare, and poor vision in patients with congenital or trauma-induced iris damage. Commercial artificial iris lenses are static in nature to provide aesthetics without restoring the natural iris's dynamic response to light. A new photo-responsive artificial iris was therefore developed using a photochromic material with self-adaptive light transmission properties and encased in a transparent biocompatible polymer matrix. Methods The implantable artificial iris was designed and engineered using Photopia, a class of photo-responsive materials (termed naphthopyrans) embedded in polyethylene. Photopia was reshaped into annular disks that were spin-coated with polydimethylsiloxane (PDMS) to form our artificial iris lens of controlled thickness. Results Activated by UV and blue light in approximately 5 seconds with complete reversal in less than 1 minute, the artificial iris demonstrates graded attenuation of up to 40% of visible and 60% of UV light. There optical characteristics are suitable to reversibly regulate the incident light intensity. In vitro cell culture experiments showed up to 60% cell death within 10 days of exposure to Photopia, but no significant cell death observed when cultured with the artificial iris with protective encapsulation. Nuclear magnetic resonance spectroscopy confirmed these results as there was no apparent leakage of potentially toxic photochromic material from the ophthalmic device. Conclusions Our artificial iris lens mimics the functionality of the natural iris by attenuating light intensity entering the eye with its rapid reversible change in opacity and thus potentially providing an improved treatment option for patients with iris damage. PMID:27116547

  16. Engineering a Light-Attenuating Artificial Iris.

    PubMed

    Shareef, Farah J; Sun, Shan; Kotecha, Mrignayani; Kassem, Iris; Azar, Dimitri; Cho, Michael

    2016-04-01

    Discomfort from light exposure leads to photophobia, glare, and poor vision in patients with congenital or trauma-induced iris damage. Commercial artificial iris lenses are static in nature to provide aesthetics without restoring the natural iris's dynamic response to light. A new photo-responsive artificial iris was therefore developed using a photochromic material with self-adaptive light transmission properties and encased in a transparent biocompatible polymer matrix. The implantable artificial iris was designed and engineered using Photopia, a class of photo-responsive materials (termed naphthopyrans) embedded in polyethylene. Photopia was reshaped into annular disks that were spin-coated with polydimethylsiloxane (PDMS) to form our artificial iris lens of controlled thickness. Activated by UV and blue light in approximately 5 seconds with complete reversal in less than 1 minute, the artificial iris demonstrates graded attenuation of up to 40% of visible and 60% of UV light. There optical characteristics are suitable to reversibly regulate the incident light intensity. In vitro cell culture experiments showed up to 60% cell death within 10 days of exposure to Photopia, but no significant cell death observed when cultured with the artificial iris with protective encapsulation. Nuclear magnetic resonance spectroscopy confirmed these results as there was no apparent leakage of potentially toxic photochromic material from the ophthalmic device. Our artificial iris lens mimics the functionality of the natural iris by attenuating light intensity entering the eye with its rapid reversible change in opacity and thus potentially providing an improved treatment option for patients with iris damage.

  17. Iris ultrastructure in patients with synechiae as revealed by in vivo laser scanning confocal microscopy : In vivo iris ultrastructure in patients with Synechiae by Laser Scanning Confocal Microscopy.

    PubMed

    Li, Ming; Cheng, Hongbo; Guo, Ping; Zhang, Chun; Tang, Song; Wang, Shusheng

    2016-04-26

    Iris plays important roles in ocular physiology and disease pathogenesis. Currently it is technically challenging to noninvasively examine the human iris ultrastructure in vivo. The purpose of the current study is to reveal human iris ultrastructure in patients with synechiae by using noninvasive in vivo laser scanning confocal microscopy (LSCM). The ultrastructure of iris in thirty one patients, each with synechiae but transparent cornea, was examined by in vivo LSCM. Five characteristic iris ultrastructures was revealed in patients with synechiae by in vivo LSCM, which include: 1. tree trunk-like structure; 2. tree branch/bush-like structure; 3. Fruit-like structure; 4. Epithelioid-like structure; 5. deep structure. Pigment granules can be observed as a loose structure on the top of the arborization structure. In iris-associated diseases with Tyndall's Phenomenon and keratic precipitates, the pigment particles are more likely to fall off from the arborization structure. The ultrastructure of iris in patients with synechiae has been visualized using in vivo LSCM. Five iris ultrastructures can be clearly observed, with some of the structures maybe disease-associated. The fall-off of the pigment particles may cause the Tyndall's Phenomenon positive. In vivo LSCM provides a non-invasive approach to observe the human iris ultrastructure under certain eye disease conditions, which sets up a foundation to visualize certain iris-associated diseases in the future.

  18. Video-based noncooperative iris image segmentation.

    PubMed

    Du, Yingzi; Arslanturk, Emrah; Zhou, Zhi; Belcher, Craig

    2011-02-01

    In this paper, we propose a video-based noncooperative iris image segmentation scheme that incorporates a quality filter to quickly eliminate images without an eye, employs a coarse-to-fine segmentation scheme to improve the overall efficiency, uses a direct least squares fitting of ellipses method to model the deformed pupil and limbic boundaries, and develops a window gradient-based method to remove noise in the iris region. A remote iris acquisition system is set up to collect noncooperative iris video images. An objective method is used to quantitatively evaluate the accuracy of the segmentation results. The experimental results demonstrate the effectiveness of this method. The proposed method would make noncooperative iris recognition or iris surveillance possible.

  19. Iris Recognition: The Consequences of Image Compression

    NASA Astrophysics Data System (ADS)

    Ives, Robert W.; Bishop, Daniel A.; Du, Yingzi; Belcher, Craig

    2010-12-01

    Iris recognition for human identification is one of the most accurate biometrics, and its employment is expanding globally. The use of portable iris systems, particularly in law enforcement applications, is growing. In many of these applications, the portable device may be required to transmit an iris image or template over a narrow-bandwidth communication channel. Typically, a full resolution image (e.g., VGA) is desired to ensure sufficient pixels across the iris to be confident of accurate recognition results. To minimize the time to transmit a large amount of data over a narrow-bandwidth communication channel, image compression can be used to reduce the file size of the iris image. In other applications, such as the Registered Traveler program, an entire iris image is stored on a smart card, but only 4 kB is allowed for the iris image. For this type of application, image compression is also the solution. This paper investigates the effects of image compression on recognition system performance using a commercial version of the Daugman iris2pi algorithm along with JPEG-2000 compression, and links these to image quality. Using the ICE 2005 iris database, we find that even in the face of significant compression, recognition performance is minimally affected.

  20. An iris recognition algorithm based on DCT and GLCM

    NASA Astrophysics Data System (ADS)

    Feng, G.; Wu, Ye-qing

    2008-04-01

    With the enlargement of mankind's activity range, the significance for person's status identity is becoming more and more important. So many different techniques for person's status identity were proposed for this practical usage. Conventional person's status identity methods like password and identification card are not always reliable. A wide variety of biometrics has been developed for this challenge. Among those biologic characteristics, iris pattern gains increasing attention for its stability, reliability, uniqueness, noninvasiveness and difficult to counterfeit. The distinct merits of the iris lead to its high reliability for personal identification. So the iris identification technique had become hot research point in the past several years. This paper presents an efficient algorithm for iris recognition using gray-level co-occurrence matrix(GLCM) and Discrete Cosine transform(DCT). To obtain more representative iris features, features from space and DCT transformation domain are extracted. Both GLCM and DCT are applied on the iris image to form the feature sequence in this paper. The combination of GLCM and DCT makes the iris feature more distinct. Upon GLCM and DCT the eigenvector of iris extracted, which reflects features of spatial transformation and frequency transformation. Experimental results show that the algorithm is effective and feasible with iris recognition.

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