Telescoping Solar Array Concept for Achieving High Packaging Efficiency

NASA Technical Reports Server (NTRS)

Mikulas, Martin; Pappa, Richard; Warren, Jay; Rose, Geoff

2015-01-01

Lightweight, high-efficiency solar arrays are required for future deep space missions using high-power Solar Electric Propulsion (SEP). Structural performance metrics for state-of-the art 30-50 kW flexible blanket arrays recently demonstrated in ground tests are approximately 40 kW/cu m packaging efficiency, 150 W/kg specific power, 0.1 Hz deployed stiffness, and 0.2 g deployed strength. Much larger arrays with up to a megawatt or more of power and improved packaging and specific power are of interest to mission planners for minimizing launch and life cycle costs of Mars exploration. A new concept referred to as the Compact Telescoping Array (CTA) with 60 kW/cu m packaging efficiency at 1 MW of power is described herein. Performance metrics as a function of array size and corresponding power level are derived analytically and validated by finite element analysis. Feasible CTA packaging and deployment approaches are also described. The CTA was developed, in part, to serve as a NASA reference solar array concept against which other proposed designs of 50-1000 kW arrays for future high-power SEP missions could be compared.

A Unique test for Hubble's new Solar Arrays

NASA Astrophysics Data System (ADS)

2000-10-01

In mid-October, a team from the European Space Agency (ESA) and NASA will perform a difficult, never-before-done test on one of the Hubble Space Telescope's new solar array panels. Two of these panels, or arrays, will be installed by astronauts in November 2001, when the Space Shuttle Columbia visits Hubble on a routine service mission. The test will ensure that the new arrays are solid and vibration free before they are installed on orbit. The test will be conducted at ESA's European Space Research and Technology Center (ESTEC) in Noordwijk, The Netherlands. Because of the array's size, the facility's special features, and ESA's longstanding experience with Hubble's solar arrays, ESTEC is the only place in the world the test can be performed. This test is the latest chapter in a longstanding partnership between ESA and NASA on the Hubble Space Telescope. The Large Space Simulator at ESTEC, ESA's world-class test facility, features a huge vacuum chamber containing a bank of extremely bright lights that simulate the Sun's intensity - including sunrise and sunset. By exposing the solar wing to the light and temperature extremes of Hubble's orbit, engineers can verify how the new set of arrays will act in space. Hubble orbits the Earth once every 90 minutes. During each orbit, the telescope experiences 45 minutes of searing sunlight and 45 minutes of frigid darkness. This test will detect any tiny vibrations, or jitters, caused by these dramatic, repeated changes. Even a small amount of jitter can affect Hubble's sensitive instruments and interfere with observations. Hubble's first set of solar arrays experienced mild jitter and was replaced in 1993 with a much more stable pair. Since that time, advances in solar cell technology have led to the development of even more efficient arrays. In 2001, NASA will take advantage of these improvements, by fitting Hubble with a third-generation set of arrays. Though smaller, this new set generates more power than the previous pairs. The arrays use high efficiency solar cells and an advanced structural system to support the solar panels. Unlike the earlier sets, which roll up like window shades, the new arrays are rigid. ESA provided Hubble's first two sets of solar arrays, and built and tested the motors and electronics of the new set provided by NASA Goddard Space Flight Center. Now, this NASA/ESA test has benefits that extend beyond Hubble to the world-wide aerospace community. It will greatly expand basic knowledge of the jitter phenomenon. Engineers across the globe can apply these findings to other spacecraft that are subjected to regular, dramatic changes in sunlight and temperature. Note to editors The Hubble Project The Hubble Space Telescope is a project of international co-operation between the National Aeronautics and Space Administration (NASA) and the European Space Agency (ESA). The partnership agreement between ESA and NASA was signed on 7 October 1977. ESA has provided two pairs of solar panels and one of Hubble's scientific instruments (the Faint Object Camera), as well as a number of other components and supports NASA during routine Servicing Missions to the telescope. In addition, 15 European scientists are working at the Space Telescope Science Institute in Baltimore (STScI), which is responsible for the scientific operation of the Hubble Observatory and is managed by the Association of Universities for Research in Astronomy (AURA) for NASA. In return, European astronomers have guaranteed access to 15% of Hubble's observing time. The Space Telescope European Coordinating Facility (ST-ECF) hosted at the European Southern Observatory (ESO) in Garching bei München, Germany, supports European Hubble users. ESA and ESO jointly operate the ST-ECF.

Multi-Spectral Solar Telescope Array. IV - The soft X-ray and extreme ultraviolet filters

NASA Technical Reports Server (NTRS)

Lindblom, Joakim F.; O'Neal, Ray H.; Walker, Arthur B. C., Jr.; Powell, Forbes R.; Barbee, Troy W., Jr.; Hoover, Richard B.

1991-01-01

NASA's Multi-Spectral Solar Telescope Array uses various combinations of thin foil filters composed of Al, C, Te, Be, Mo, Rh, and phthalocyanine to achieve the requisite radiation-rejection characteristics. Such rejection is demanded by the presence of strong EUV radiation at longer wavelengths where the specular reflectivity of multilayer mirrors can cause 'contamination' of the image in the narrow band defined by the Bragg condition.

EVA 2 - MS Newman and Massimino over Australia

NASA Image and Video Library

2002-03-05

STS109-E-5610 (5 March 2002) --- Astronauts James H. Newman, attached to the Remote Manipulator System (RMS) arm of the Space Shuttle Columbia, and Michael J. Massimino (barely visible against the Hubble Space Telescope near center frame) work on the telescope as the shuttle flies over Australia. This day's space walk went on to see astronauts Newman and Massimino replace the port solar array on the Hubble. On the previous day astronauts John M. Grunsfeld and Richard M. Linnehan replaced the starboard solar array on the giant telescope. The image was recorded with a digital still camera.

Computer-generated scenes depicting the HST capture and EVA repair mission

NASA Image and Video Library

1993-11-12

Computer generated scenes depicting the Hubble Space Telescope capture and a sequence of planned events on the planned extravehicular activity (EVA). Scenes include the Remote Manipulator System (RMS) arm assisting two astronauts changing out the Wide Field/Planetary Camera (WF/PC) (48699); RMS arm assisting in the temporary mating of the orbiting telescope to the flight support system in Endeavour's cargo bay (48700); Endeavour's RMS arm assisting in the "capture" of the orbiting telescope (48701); Two astronauts changing out the telescope's coprocessor (48702); RMS arm assistign two astronauts replacing one of the telescope's electronic control units (48703); RMS assisting two astronauts replacing the fuse plugs on the telescope's Power Distribution Unit (PDU) (48704); The telescope's High Resolution Spectrograph (HRS) kit is depicted in this scene (48705); Two astronauts during the removal of the high speed photometer and the installation of the COSTAR instrument (48706); Two astronauts, standing on the RMS, during installation of one of the Magnetic Sensing System (MSS) (48707); High angle view of the orbiting Space Shuttle Endeavour with its cargo bay doors open, revealing the bay's pre-capture configuration. Seen are, from the left, the Solar Array Carrier, the ORU Carrier and the flight support system (48708); Two astronauts performing the replacement of HST's Rate Sensor Units (RSU) (48709); The RMS arm assisting two astronauts with the replacement of the telescope's solar array panels (48710); Two astronauts replacing the telescope's Solar Array Drive Electronics (SADE) (48711).

STS-31 Hubble Space Telescope (HST) solar array panel deploy aboard OV-103

NASA Image and Video Library

1990-04-25

Held in appendage deploy position by Discovery's, Orbiter Vehicle (OV) 103's, remote manipulator system (RMS), the Hubble Space Telescope's (HST's) starboard solar array (SA) bistem cassette is released from its stowed position on the Support System Module (SSM) forward shell. The spreader bar & bistem begin to unfurl the SA wing. View was taken by an STS-31 crewmember through an overhead window & is backdropped against the surface of the Earth.

STS-109 MS Grunsfeld and Linnehan stow old solar array from payload bay

NASA Image and Video Library

2002-03-04

STS109-E-5244 (4 March 2002) --- Astronauts John M. Grunsfeld (red stripes on suit), payload commander, and Richard M. (Rick) Linnehan, mission specialist, participate in the first of their assigned STS-109 space walks to perform work on the Hubble Space Telescope (HST). The two went on to replace the giant telescope’s starboard solar array. Their seven-hour space walk ended at 7:38 a.m. (CST) or 13:38 GMT March 4, 2002.

Thermal Performance of the Hubble Space Telescope (HST) Solar Array-3 During the Disturbance Verification Test (DVT)

NASA Technical Reports Server (NTRS)

Nguyen, Daniel H.; Skladany, Lynn M.; Prats, Benito D.; Griffin, Thomas J. (Technical Monitor)

2001-01-01

The Hubble Space Telescope (HST) is one of NASA's most productive astronomical observatories. Launched in 1990, the HST continues to gather scientific data to help scientists around the world discover amazing wonders of the universe. To maintain HST in the fore front of scientific discoveries, NASA has routinely conducted servicing missions to refurbish older equipment as well as to replace existing scientific instruments with better, more powerful instruments. In early 2002, NASA will conduct its fourth servicing mission to the HST. This servicing mission is named Servicing Mission 3B (SM3B). During SM3B, one of the major refurbishment efforts will be to install new rigid-panel solar arrays as a replacement for the existing flexible-foil solar arrays. This is necessary in order to increase electrical power availability for the new scientific instruments. Prior to installing the new solar arrays on HST, the HST project must be certain that the new solar arrays will not cause any performance degradations to the observatory. One of the major concerns is any disturbance that can cause pointing Loss of Lock (LOL) for the telescope. While in orbit, the solar-array temperature transitions quickly from sun to shadow. The resulting thermal expansion and contraction can cause a "mechanical disturbance" which may result in LOL. To better characterize this behavior, a test was conducted at the European Space Research and Technology Centre (ESTEC) in the Large Space Simulator (LSS) thermal-vacuum chamber. In this test, the Sun simulator was used to simulate on-orbit effects on the solar arrays. This paper summarizes the thermal performance of the Solar Array-3 (SA3) during the Disturbance Verification Test (DVT). The test was conducted between 26 October 2000 and 30 October 2000. Included in this paper are: (1) brief description of the SA3's components and its thermal design; (2) a summary of the on-orbit temperature predictions; (3) pretest thermal preparations; (4) a description of the chamber and thermal monitoring sensors; and (6) presentation of test thermal data results versus flight predictions.

STS-109 MS Grunsfeld and Linnehan stow old solar array from payload bay

NASA Image and Video Library

2002-03-04

STS109-E-5246 (4 March 2002) --- Astronaut John M. Grunsfeld (foreground), payload commander, is seen at one end of stowed solar panels in the cargo bay of the Space Shuttle Columbia while astronaut Richard M. Linnehan, mission specialist, uses the Remote Manipulator System's robotic arm to move around at the other end. The two, participating in the first of their assigned STS-109 space walks to perform work on the Hubble Space Telescope (HST), went on to replace the giant telescope’s starboard solar array. Their seven-hour space walk ended at 7:38 a.m. (CST) or 13:38 GMT March 4, 2002.

STS-109 Flight Day 3 Highlights

NASA Technical Reports Server (NTRS)

2002-01-01

This footage from the third day of the STS-109 mission to service the Hubble Space Telescope (HST) begins with the grappling of the HST by the robotic arm of the Columbia Orbiter, operated by Mission Specialist Nancy Currie. During the grappling, numerous angles deliver close-up images of the telescope which appears to be in good shape despite many years in orbit around the Earth. Following the positioning of the HST on its berthing platform in the Shuttle bay, the robotic arm is used to perform an external survey of the telescope. Some cursory details are given about different equipment which will be installed on the HST including a replacement cooling system for the Near Infrared Camera Multi-Object Spectrometer (NICMOS) and the Advanced Camera for Surveys. Following the survey, there is footage of the retraction of both of the telescope's two flexible solar arrays, which was successful. These arrays will be replaced by rigid solar arrays with decreased surface area and increased performance.

EVA 2 - MS Newman over Australia

NASA Image and Video Library

2002-03-05

STS109-E-5611 (5 March 2002) --- Astronauts James H. Newman, attached to the Remote Manipulator System (RMS) arm of the Space Shuttle Columbia, and Michael J. Massimino (out of frame) work on the Hubble Space Telescope as the shuttle flies over Western Australia. This day's space walk went on to see astronauts Newman and Massimino replace the port solar array on the Hubble. On the previous day astronauts John M. Grunsfeld and Richard M. Linnehan replaced the starboard solar array on the giant telescope. The image was recorded with a digital still camera.

STS-31 Hubble Space Telescope (HST) solar array (SA) deploy aboard OV-103

NASA Image and Video Library

1990-04-25

During STS-31, the Hubble Space Telescope (HST) is held in appendage deploy position by Discovery's, Orbiter Vehicle (OV) 103's, remote manipulator system (RMS) above the payload bay (PLB) and crew compartment cabin. While in this position the solar array (SA) wing bistem cassette (HST center) is deployed from its stowed location along side the Support System Module (SSM) forward shell. A high gain antenna (HGA) remains stowed along the SSM. The Earth's surface and the Earth limb creates a dramatic backdrop.

Photoelectric array detectors for use at XUV wavelengths. [for Spacelab solar-physics facilities

NASA Technical Reports Server (NTRS)

Timothy, J. G.

1981-01-01

The characteristics of photoelectric detector systems for use at visible-light, ultraviolet, and X-ray wavelengths are briefly reviewed in the context of the needs of the Spacelab solar-physics facilities. Photoelectric array detectors for use at XUV wavelengths between 90 and 1500 A are described, and their use in the ESA Grazing-Incidence Solar Telescope (GRIST) facility is discussed.

Space Shuttle Projects

NASA Image and Video Library

2002-03-07

STS-109 Astronaut Michael J. Massimino, mission specialist, perched on the Shuttle's robotic arm is working at the stowage area for the Hubble Space Telescope's port side solar array. Working in tandem with James. H. Newman, Massimino removed the old port solar array and stored it in Columbia's payload bay for return to Earth. The two went on to install a third generation solar array and its associated electrical components. Two crew mates had accomplished the same feat with the starboard array on the previous day. In addition to the replacement of the solar arrays, the STS-109 crew also installed the experimental cooling system for the Hubble's Near-Infrared Camera (NICMOS), replaced the power control unit (PCU), and replaced the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS). The 108th flight overall in NASA's Space Shuttle Program, the Space Shuttle Columbia STS-109 mission lifted off March 1, 2002 for 10 days, 22 hours, and 11 minutes. Five space walks were conducted to complete the HST upgrades. The Marshall Space Flight Center in Huntsville, Alabama had the responsibility for the design, development, and construction of the HST, which is the most powerful and sophisticated telescope ever built.

Design progress of the solar UV-Vis-IR telescope (SUVIT) aboard SOLAR-C

NASA Astrophysics Data System (ADS)

Katsukawa, Y.; Ichimoto, K.; Suematsu, Y.; Hara, H.; Kano, R.; Shimizu, T.; Matsuzaki, K.

2013-09-01

We present a design progress of the Solar UV-Vis-IR Telescope (SUVIT) aboard the next Japanese solar mission SOLAR-C. SUVIT has an aperture diameter of ~1.4 m for achieving spectro-polarimetric observations with spatial and temporal resolution exceeding the Hinode Solar Optical Telescope (SOT). We have studied structural and thermal designs of the optical telescope as well as the optical interface between the telescope and the focal plane instruments. The focal plane instruments are installed into two packages, filtergraph and spectrograph packages. The spectropolarimeter is the instrument dedicated to accurate polarimetry in the three spectrum windows at 525 nm, 854 nm, and 1083 nm for observing magnetic fields at both the photospheric and chromospheric layers. We made optical design of the spectrograph accommodating the conventional slit spectrograph and the integral field unit (IFU) for two-dimensional coverage. We are running feasibility study of the IFU using fiber arrays consisting of rectangular cores.

HST Solar Arrays photographed by Electronic Still Camera

NASA Image and Video Library

1993-12-07

S61-E-020 (7 Dec 1993) --- This close-up view of one of two Solar Arrays (SA) on the Hubble Space Telescope (HST) was photographed with an Electronic Still Camera (ESC), and down linked to ground controllers soon afterward. Endeavour's crew captured the HST on December 4, 1993, in order to service the telescope over a period of five days. Four of the crew members will work in alternating pairs outside Endeavour's shirt sleeve environment to service the giant telescope. Electronic still photography is a relatively new technology which provides the means for a handheld camera to electronically capture and digitize an image with resolution approaching film quality. The electronic still camera has flown as an experiment on several other shuttle missions.

Astronaut Story Musgrave during deployment of solar array panels on HST

NASA Image and Video Library

1993-12-09

STS061-48-027 (9 Dec 1993) --- Astronaut F. Story Musgrave moves about in the Space Shuttle Endeavour's cargo bay during the deployment of the solar array panels on the Hubble Space Telescope (HST) during the final of five STS-61 space walks. The left hand of astronaut Jeffrey A. Hoffman appears at lower left corner.

HST Solar Arrays photographed by Electronic Still Camera

NASA Technical Reports Server (NTRS)

1993-01-01

This close-up view of one of two Solar Arrays (SA) on the Hubble Space Telescope (HST) was photographed with an Electronic Still Camera (ESC), and downlinked to ground controllers soon afterward. Electronic still photography is a technology which provides the means for a handheld camera to electronically capture and digitize an image with resolution approaching film quality.

Argus: A W-band 16-pixel focal plane array for the Green Bank Telescope

NASA Astrophysics Data System (ADS)

Devaraj, Kiruthika; Church, Sarah; Cleary, Kieran; Frayer, David; Gawande, Rohit; Goldsmith, Paul; Gundersen, Joshua; Harris, Andrew; Kangaslahti, Pekka; Readhead, Tony; Reeves, Rodrigo; Samoska, Lorene; Sieth, Matt; Voll, Patricia

2015-05-01

We are building Argus, a 16-pixel square-packed focal plane array that will cover the 75-115.3 GHz frequency range on the Robert C. Byrd Green Bank Telescope (GBT). The primary research area for Argus is the study of star formation within our Galaxy and nearby galaxies. Argus will map key molecules that trace star formation, including carbon monoxide (CO) and hydrogen cyanide (HCN). An additional key science area is astrochemistry, which will be addressed by observing complex molecules in the interstellar medium, and the study of formation of solar systems, which will be addressed by identifying dense pre-stellar cores and by observing comets in our solar system. Argus has a highly scalable architecture and will be a technology path finder for larger arrays. The array is modular in construction, which will allow easy replacement of malfunctioning and poorly performing components.

Point-Focus Concentration Compact Telescoping Array: Extreme Environments Solar Power Base Phase Final Report

NASA Technical Reports Server (NTRS)

McEachen, Michael E.; Murphy, Dave; Meinhold, Shen; Spink, Jim; Eskenazi, Mike; O'Neill, Mark

2017-01-01

Orbital ATK, in partnership with Mark ONeill LLC (MOLLC), has developed a novel solar array platform, PFC-CTA, which provides a significant advance in performance and cost reduction compared to all currently available space solar systems. PFC refers to the Point Focus Concentration of light provided by MOLLCs thin, flat Fresnel optics. These lenses focus light to a point of approximately 100 times the intensity of the ambient light, onto a solar cell of approximately 125th the size of the lens. CTA stands for Compact Telescoping Array, which is the solar array blanket structural platform originally devised by NASA and currently being advanced by Orbital ATK and partners under NASA and AFRL funding to a projected TRL 5+ by late-2018.The NASA Game Changing Development Extreme Environment Solar Power (EESP) Base Phase study has enabled Orbital ATK to refine component designs, perform component level and system performance analyses, and test prototype hardware of the key elements of PFC-CTA, and increased the TRL of PFC-specific technology elements to TRL 4. Key performance metrics currently projected are as follows: Scalability from 5 kW to 300 kW per wing (AM0); Specific Power 500 Wkg (AM0); Stowage Efficiency 100 kWm3; 5:1 margin on pointing tolerance vs. capability; 50 launched cost savings; Wide range of operability between Venus and Saturn by active andor passive thermal management.

HST Solar Arrays photographed by Electronic Still Camera

NASA Image and Video Library

1993-12-04

S61-E-002 (4 Dec 1993) --- This view, backdropped against the blackness of space shows one of two original Solar Arrays (SA) on the Hubble Space Telescope (HST). The scene was photographed from inside Endeavour's cabin with an Electronic Still Camera (ESC), and down linked to ground controllers soon afterward. This view features the minus V-2 panel. Endeavour's crew captured the HST on December 4, 1993 in order to service the telescope over a period of five days. Four of the crew members will work in alternating pairs outside Endeavour's shirt sleeve environment to service the giant telescope. Electronic still photography is a relatively new technology which provides the means for a handheld camera to electronically capture and digitize an image with resolution approaching film quality. The electronic still camera has flown as an experiment on several other shuttle missions.

HST Solar Arrays photographed by Electronic Still Camera

NASA Image and Video Library

1993-12-04

S61-E-003 (4 Dec 1993) --- This medium close-up view of one of two original Solar Arrays (SA) on the Hubble Space Telescope (HST) was photographed with an Electronic Still Camera (ESC), and down linked to ground controllers soon afterward. This view shows the cell side of the minus V-2 panel. Endeavour's crew captured the HST on December 4, 1993 in order to service the telescope over a period of five days. Four of the crew members will work in alternating pairs outside Endeavour's shirt sleeve environment to service the giant telescope. Electronic still photography is a relatively new technology which provides the means for a handheld camera to electronically capture and digitize an image with resolution approaching film quality. The electronic still camera has flown as an experiment on several other shuttle missions.

EVA 2 activity on Flight Day 5 to survey the HST solar array panels

NASA Image and Video Library

1997-02-15

STS082-719-002 (14 Feb. 1997) --- Astronaut Joseph R. Tanner (right) stands on the end of Discovery's Remote Manipulator System (RMS) arm and aims a camera at the solar array panels on the Hubble Space Telescope (HST) as astronaut Gregory J. Harbaugh assists. The second Extravehicular Activity (EVA) photograph was taken with a 70mm camera from inside Discovery's cabin.

HST Solar Arrays photographed by Electronic Still Camera

NASA Technical Reports Server (NTRS)

1993-01-01

This view, backdropped against the blackness of space shows one of two original Solar Arrays (SA) on the Hubble Space Telescope (HST). The scene was photographed with an Electronic Still Camera (ESC), and downlinked to ground controllers soon afterward. Electronic still photography is a technology which provides the means for a handheld camera to electronically capture and digitize an image with resolution approaching film quality.

Life Cycle Testing of Viscoelastic Material for Hubble Space Telescope Solar Array 3 Damper

NASA Technical Reports Server (NTRS)

Maly, Joseph R.; Reed, Benjamin B.; Viens, Michael J.; Parker, Bradford H.; Pendleton, Scott C.

2003-01-01

During the March 2002 Servicing Mission by Space Shuttle (STS 109), the Hubble Space Telescope (HST) was refurbished with two new solar arrays that now provide all of its power. These arrays were built with viscoelastic/titanium dampers, integral to the supporting masts, which reduce the interaction of the wing bending modes with the Telescope. Damping of over 3% of critical was achieved. To assess the damper s ability to maintain nominal performance over the 10-year on-orbit design goal, material specimens were subjected to an accelerated life test. The test matrix consisted of scheduled events to expose the specimens to pre-determined combinations of temperatures, frequencies, displacement levels, and numbers of cycles. These exposure events were designed to replicate the life environment of the damper from fabrication through testing to launch and life on-orbit. To determine whether material degradation occurred during the exposure sequence, material performance was evaluated before and after the accelerated aging with complex stiffness measurements. Based on comparison of pre- and post-life-cycle measurements, the material is expected to maintain nominal performance through end of life on-orbit. Recent telemetry from the Telescope indicates that the dampers are performing nominally.

Skylab technology electrical power system

NASA Technical Reports Server (NTRS)

Woosley, A. P.; Smith, O. B.; Nassen, H. S.

1974-01-01

The solar array/battery power systems for the Skylab vehicle were designed to operate in a solar inertial pointing mode to provide power continuously to the Skylab. Questions of power management are considered, taking into account difficulties caused by the reduction in power system performance due to the effects of structural failure occurring during the launching process. The performance of the solar array of the Apollo Telescope Mount Power System is discussed along with the Orbital Workshop solar array performance and the Airlock Module power conditioning group performance. A list is presented of a number of items which have been identified during mission monitoring and are recommended for electrical power system concepts, designs, and operation for future spacecraft.

Thermally Induced Vibrations of the Hubble Space Telescope's Solar Array 3 in a Test Simulated Space Environment

NASA Technical Reports Server (NTRS)

Early, Derrick A.; Haile, William B.; Turczyn, Mark T.; Griffin, Thomas J. (Technical Monitor)

2001-01-01

NASA Goddard Space Flight Center and the European Space Agency (ESA) conducted a disturbance verification test on a flight Solar Array 3 (SA3) for the Hubble Space Telescope using the ESA Large Space Simulator (LSS) in Noordwijk, the Netherlands. The LSS cyclically illuminated the SA3 to simulate orbital temperature changes in a vacuum environment. Data acquisition systems measured signals from force transducers and accelerometers resulting from thermally induced vibrations of the SAI The LSS with its seismic mass boundary provided an excellent background environment for this test. This paper discusses the analysis performed on the measured transient SA3 responses and provides a summary of the results.

EVA 2 - MS Massimino waves to crewmates

NASA Image and Video Library

2002-03-05

STS109-E-5606 (5 March 2002) --- Astronaut Michael J. Massimino, mission specialist, waves to crewmates on the other side of the aft flight deck windows on Columbia, while equipped with his extravehicular mobility units (EMU) space suit and standing on the end of the Remote Manipulator System (RMS) arm in the shuttle's cargo bay. This day's space walk went on to see astronauts James H. Newman and Massimino replace the port solar array on the Hubble Space Telescope (HST), partially visible in the background. On the previous day astronauts John M. Grunsfeld and Richard M. Linnehan replaced the starboard solar array on the giant telescope. The image was recorded with a digital still camera.

The First Focused Hard X-Ray Images of the Sun with NuSTAR

NASA Technical Reports Server (NTRS)

Grefenstette, Brian W.; Glesener, Lindsay; Kruckner, Sam; Hudson, Hugh; Hannah, Iain G.; Smith, David M.; Vogel, Julia K.; White, Stephen M.; Madsen, Kristin K.; Marsh, Andrew J.;

HST Solar Arrays photographed by Electronic Still Camera

NASA Technical Reports Server (NTRS)

1993-01-01

This medium close-up view of one of two original Solar Arrays (SA) on the Hubble Space Telescope (HST) was photographed with an Electronic Still Camera (ESC), and downlinked to ground controllers soon afterward. This view shows the cell side of the minus V-2 panel. Electronic still photography is a technology which provides the means for a handheld camera to electronically capture and digitize an image with resolution approaching film quality.

Development of compact integral field unit for spaceborne solar spectro-polarimeter

NASA Astrophysics Data System (ADS)

Suematsu, Y.; Koyama, M.; Sukegawa, T.; Enokida, Y.; Saito, K.; Okura, Y.; Nakayasu, T.; Ozaki, S.; Tsuneta, S.

2017-11-01

A 1.5-m class aperture Solar Ultra-violet Visible and IR telescope (SUVIT) and its instruments for the Japanese next space solar mission SOLAR-C [1] are under study to obtain critical physical parameters in the lower solar atmosphere. For the precise magnetic field measurements covering field-of-view of 3 arcmin x3 acmin, a full stokes polarimetry at three magnetic sensitive lines in wavelength range of 525 nm to 1083 nm with a four-slit spectrograph of two dinesional image scanning mechanism is proposed: one is a true slit and the other three are pseudo-slits from integral field unit (IFU). To suit this configuration, besides a fiber bundle IFU, a compact mirror slicer IFU is designed and being developed. Integral field spectroscopy (IFS), which is realized with IFU, is a two dimensional spectroscopy, providing spectra simultaneously for each spatial direction of an extended two-dimensional field. The scientific advantages of the IFS for studies of localized and transient solar surface phenomena are obvious. There are in general three methods [2][3] to realize the IFS depending on image slicing devices such as a micro-lenslet array, an optical fiber bundle and a narrow rectangular image slicer array. So far, there exist many applications of the IFS for ground-based astronomical observations [4]. Regarding solar instrumentations, the IFS of micro-lenslet array was done by Suematsu et al. [5], the IFS of densely packed rectangular fiber bundle with thin clads was realized [6] and being developed for 4-m aperture solar telescope DKIST by Lin [7] and being considered for space solar telescope SOLAR-C by Katsukawa et al. [8], and the IFS with mirror slicer array was presented by Ren et al. [9] and under study for up-coming large-aperture solar telescope in Europe by Calcines et al. [10] From the view point of a high efficiency spectroscopy, a wide wavelength coverage, a precision spectropolarimetry and space application, the image slicer consisting of all reflective optics is the best option among the three. However, the image slicers are presently limited either by their risk in the case of classical glass polishing techniques (see Vivès et al. [11] for recent development) or by their optical performances when constituted by metallic mirrors. For space instruments, small sized units are much advantageous and demands that width of each slicer mirror is as narrow as an optimal slit width (< 100 micron) of spectrograph which is usually hard to manufacture with glass polishing techniques. On the other hand, Canon is developing a novel technique for such as high performance gratings which can be applicable for manufacturing high optical performance metallic mirrors of small dimensions. For the space-borne spectrograph of SUVIT to be aboard SOLAR-C, we designed the IFS made of a micro image slicer of 45 arrayed 30-micron-thick metal mirrors and a pseudo-pupil metal mirror array re-formatting three pseudo-slits; the design is feasible for optical configuration sharing a spectrograph with a conventional real slit. According to the optical deign, Canon manufactured a prototype IFU for evaluation, demonstrating high performances of micro image slicer and pupil mirrors; enough small micro roughness for visible light spectrographs, sharp edges for efficient image slices, surface figure for high image quality, etc. In the following, we describe the optical design of IFU feasible for space-borne spectrograph, manufacturing method to attain high optical performance of metal mirrors developed by Canon, and resulted performance of prototype IFU in detail.

Hubble Space Telescope Servicing begins.

NASA Astrophysics Data System (ADS)

1993-12-01

The day's work began when astronauts Story Musgrave and Jeff Hoffman stepped out into the cargo bay at 9h41 pm CST, Saturday (4h41 am CET, Sunday). They immediately set to work replacing two gyroscope assemblies, known as the Rate Sensor Units, two associated electronics boxes, called Electronic Control Units, and eight electrical fuse plugs. The work was completed ahead of schedule, but the astronauts had trouble closing the doors of the compartment housing the gyros and took over an hour to get them shut. The astronauts also prepared equipment for the replacement of the solar arrays. "The feeling down here is one of great satisfaction for a tremendous job today" said spacecraft communicator Greg Harbaugh in mission control. "We are very proud of the work that you all did and we are very confident in the continued success of the mission. Everything is going great and tomorrow is going to be another great day". ESA astronaut Claude Nicollier played a vital role during the spacewalk moving the astronauts and their equipment around the cargo bay with the shuttle's robot arm. The Hubble Space Telescope servicing mission features more robot arm operations than any other shuttle flight. The telescope's left-hand solar array was rolled up successfully at 6h24 am CST (1h24 pm CET). The 11-tonne observatory was rotated 180 degrees on its turntable before commands were sent to retract the second array at 8h23 am CST (3h23 pm CET). The crew stopped the retraction when it appeared the system may have jammed. Mission control instructed the crew to jettison the array, a procedure that they have trained for. Tomorrow astronauts Kathy Thornton and Tom Akers will make a six-hour spacewalk to jettison the troublesome wing, store the other in the cargo bay, and install two new panels supplied by ESA. The second set of arrays feature thermal shields and a modified thermal compensation system to prevent the flexing that affected the first pair. The Hubble Space Telescope was plucked from orbit this Saturday by ESA astronaut Claude Nicollier, operating the shuttle's robot arm. The Swiss-born astronaut gripped the 11- tonne observatory with the shuttle's 15-metre long robot arm at 2h34 am CST (9h34 am CET) after a two-day chase through space as the two spacecraft flew over the South Pacific Ocean. "Endeavour has a firm handshake with Mr. Hubble's telescope" said mission commander Dick Covey. "It's quite a sight". About half an hour later Nicollier had the telescope berthed on a special turntable in the back of the Shuttle's cargo bay. Later he used the camera at the end of the arm to surveyed the telescope for any damage. As the shuttle approached the telescope the astronauts first reported that one of the twin solar arrays appeared to be bowed and twisted. ESA officials said the problem was caused by the failure in early 1992 of the tensioning system on one side of the right-hand array. The system is designed to allow the blanket-like array to expand and contract in orbit. That failure placed stress on one of the supporting bi-stem booms resulting in its bent condition. Endeavour's mission began Thursday 2 December and will end 13 December. A total of five spacewalks are planned to service the telescope.

The first focused hard X-ray images of the sun with NuSTAR

DOE PAGES

Grefenstette, Brian W.; Glesener, Lindsay; Krucker, Sam; ...

2016-07-18

Here, we present results from the the first campaign of dedicated solar observations undertaken by the Nuclear Spectroscopic Telescope ARray (NuSTAR) hard X-ray (HXR) telescope. Designed as an astrophysics mission, NuSTAR nonetheless has the capability of directly imaging the Sun at HXR energies (>3 keV) with an increase in sensitivity of at least two magnitude compared to current non-focusing telescopes. In this paper we describe the scientific areas where NuSTAR will make major improvements on existing solar measurements. We report on the techniques used to observe the Sun with NuSTAR, their limitations and complications, and the procedures developed to optimizemore » solar data quality derived from our experience with the initial solar observations. These first observations are briefly described, including the measurement of the Fe K-shell lines in a decaying X-class flare, HXR emission from high in the solar corona, and full-disk HXR images of the Sun.« less

The first focused hard X-ray images of the sun with NuSTAR

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

Grefenstette, Brian W.; Glesener, Lindsay; Krucker, Sam

Here, we present results from the the first campaign of dedicated solar observations undertaken by the Nuclear Spectroscopic Telescope ARray (NuSTAR) hard X-ray (HXR) telescope. Designed as an astrophysics mission, NuSTAR nonetheless has the capability of directly imaging the Sun at HXR energies (>3 keV) with an increase in sensitivity of at least two magnitude compared to current non-focusing telescopes. In this paper we describe the scientific areas where NuSTAR will make major improvements on existing solar measurements. We report on the techniques used to observe the Sun with NuSTAR, their limitations and complications, and the procedures developed to optimizemore » solar data quality derived from our experience with the initial solar observations. These first observations are briefly described, including the measurement of the Fe K-shell lines in a decaying X-class flare, HXR emission from high in the solar corona, and full-disk HXR images of the Sun.« less

THE FIRST FOCUSED HARD X-RAY IMAGES OF THE SUN WITH NuSTAR

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

Grefenstette, Brian W.; Madsen, Kristin K.; Forster, Karl

We present results from the the first campaign of dedicated solar observations undertaken by the Nuclear Spectroscopic Telescope ARray ( NuSTAR ) hard X-ray (HXR) telescope. Designed as an astrophysics mission, NuSTAR nonetheless has the capability of directly imaging the Sun at HXR energies (>3 keV) with an increase in sensitivity of at least two magnitude compared to current non-focusing telescopes. In this paper we describe the scientific areas where NuSTAR will make major improvements on existing solar measurements. We report on the techniques used to observe the Sun with NuSTAR , their limitations and complications, and the procedures developedmore » to optimize solar data quality derived from our experience with the initial solar observations. These first observations are briefly described, including the measurement of the Fe K-shell lines in a decaying X-class flare, HXR emission from high in the solar corona, and full-disk HXR images of the Sun.« less

Thermally-Induced Structural Disturbances of Rigid Panel Solar Arrays

NASA Technical Reports Server (NTRS)

Johnston, John D.; Thornton, Earl A.

1997-01-01

The performance of a significant number of spacecraft has been impacted negatively by attitude disturbances resulting from thermally-induced motions of flexible structures. Recent examples of spacecraft affected by these disturbances include the Hubble Space Telescope (HST) and the Upper Atmosphere Research Satellite (UARS). Thermally-induced structural disturbances occur as the result of rapid changes in thermal loading typically initiated as a satellite exits or enters the Earth's shadow. Temperature differences in flexible appendages give rise to structural deformations, which in turn result in disturbance torques reacting back on the spacecraft. Structures which have proven susceptible to these disturbances include deployable booms and solar arrays. This paper investigates disturbances resulting from thermally-induced deformations of rigid panel solar arrays. An analytical model for the thermal-structural response of the solar array and the corresponding disturbance torque are presented. The effect of these disturbances on the attitude dynamics of a simple spacecraft is then investigated using a coupled system of governing equations which includes the effects of thermally-induced deformations. Numerical results demonstrate the effect of varying solar array geometry on the dynamic response of the system.

Astronauts Hoffman and Musgrave replace Solar Array Drive Electronics

NASA Image and Video Library

1993-12-09

STS061-102-010 (9 Dec 1993) --- Astronauts Jeffrey A. Hoffman (left) and F. Story Musgrave team to replace one of two Solar Array Drive Electronics (SADE) units on the Hubble Space Telescope (HST). Musgrave is standing on a foot restraint mounted on the end of the Space Shuttle Endeavour's Remote Manipulator System (RMS) arm. The black object, in upper left corner, is part of the window frame, through which this 70mm frame was exposed, inside Endeavour's cabin.

MS Grunsfeld and Linnehan on middeck after EVA 1

NASA Image and Video Library

2002-03-04

STS109-349-027 (4 March 2002) --- Astronauts John M. Grunsfeld and Richard M. Linnehan, STS-109 payload commander and mission specialist, respectively, wearing the liquid cooling and ventilation garment that complements the Extravehicular Mobility Unit (EMU) space suit, are photographed on the mid deck of the Space Shuttle Columbia after the mission’s first session of extravehicular activity (EVA). The EVA-1 team replaced one of the telescope’s two second-generation solar arrays, which is also known as SA2, and a Diode Box Assembly. The solar array was replaced with a new, third-generation solar array, which is called SA3. The space walkers also did some prep work for STS-109’s other space walks.

Highlighting the history of Japanese radio astronomy. 4: early solar research in Osaka

NASA Astrophysics Data System (ADS)

Orchiston, Wayne; Nakamura, Tsuko; Ishiguro, Masato

2016-12-01

For about two years, from late 1949, Minoru Oda and Tatsuo Takakura carried out solar observations from Osaka, initially with a hand-made horn and later with a small parabolic antenna connected to a 3.3 GHz receiver, but they only published one short paper on this work. At about the same time, Ojio and others at Osaka City University presented the concept of a solar grating array at a meeting of the Japan Physical Society, but this was never built. In this paper, we provide brief biographical accounts of Oda and Takakura before examining their radio telescopes and the observations that they made. We also briefly discuss the proposed Japanese solar grating array.

Loads Produced During the Ingression and Egression of the Portable Foot Restraint on the Hubble Space Telescope

NASA Technical Reports Server (NTRS)

Ramsey, Susan; Rajulu, Sudhakar

2000-01-01

The Hubble Space Telescope (HST) was deployed from the Space Shuttle Discovery on April 25, 1990. It is capable of performing observations in the visible, near-ultraviolet, and near-infrared (1150 A to 1 mm). The HST weighs 12 tons, and collects light with an 8-ft-diameter mirror. The attitude control and maneuvering is performed by four of six gyroscopes, or reaction wheels. The HST contains fine guidance sensors that lock onto guide stars to reduce the spacecraft drift and increase the pointing accuracy. The HST was designed to last 15 years, with crewed service missions approximately every three years. The first service mission, STS-61, took place in 1993. The second service mission took place in 1997. In 1999, the STS-103 crew performed the third service mission to the HST. This mission's purpose was to replace the right sensor units and make improvements on the fine guidance sensors. To perform these tasks on the HST, the STS-103 crewmembers used a portable foot restraint to anchor themselves to the HST in the zero-gravity environment. The solar arrays currently used on the telescope are second-generation, and therefore susceptible to loads placed on the telescope. The crew and Mission Operations Directorate worried about the damage that the crew could possibly cause during ingress and egress of the PFR and by transferring loads to the solar arrays. The purpose of this study is to inform the crewmembers of the loads they are imparting on the HST, and train them to decrease these loads to a safer level. Minimizing these loads will significantly decrease the chance of crewmembers causing damage to the solar arrays while repairing the HST.

Design of the Polarimeter for the Fibre Arrayed Solar Optical Telescope

NASA Astrophysics Data System (ADS)

Dun, Guang-tao; Qu, Zhong-quan

2013-01-01

The theoretical design of the polarimeter used for the Fibre Arrayed Solar Optical Telescope (FASOT) is described. It has the following characteris- tics: (1) It is provided with the function of optical polarization switching, which makes the high-effciency polarimetry possible; (2) In the waveband of 750 nm, the polarimetric effciency is higher than 50% for the every Stokes parameter, and higher than 86.6% for the total polarization, thus an observer can make the simultaneous polarization measurements on multiple magnetosensitive lines in such a broad range of wavelength; (3) According to the selected photospheric and chromospheric lines, the measurement can be focused on either linear polarization or circular polarization; (4) The polarimeter has a loose tolerance on the manufacturing technology of polarimetric elements and installation errors. All this makes this polarimeter become a high-performance polarimetric device.

Long Duration Exposure Facility Space Optics Handbook

DTIC Science & Technology

1993-09-01

apparent (Ref. 12). The solar cell covers showed similar impact damage as the refractive optics components. 4-1020 Si i -i 10 • 4.12, Related Material...coatings, which worsens the synergistic A(0 0 cr()Sil Oi on Uateia IS, 11nd canl Upset olties, issoc iated telescope baffles, solar cells , star 0 0 trackers...and material processes which address S primarily solar array materials, including solar cell -, 0 composites, thin films, paints, metals and other

Application of a silicon photodiode array for solar edge tracking in the Halogen Occultation Experiment

NASA Technical Reports Server (NTRS)

Mauldin, L. E., III; Moore, A. S.; Stump, C. S.; Mayo, L. S.

1985-01-01

The optical and electronic design of the Halogen Occultation Experiment (HALOE) elevation sunsensor is described. This system uses a Galilean telescope to form a solar image on a linear silicon photodiode array. The array is a self-scanned, monolithic charge coupled device. The addresses of both solar edges imaged on the array are used by the control/pointing system to scan the HALOE science instantaneous-field-of-view (IFOV) across the vertical solar diameter during instrument calibration, and then maintain the science IFOV four arcmin below the top edge during the science data occultation event. Vertical resolution of 16 arcsec and a radiometric dynamic range of 100 are achieved at the 0.7 micrometer operating wavelength. The design provides for loss of individual photodiode elements without loss of angular tracking capability. The HALOE instrument is a gas correlation radiometer that is now being developed by NASA Langley Research Center for the Upper Atmospheric Research Satellite.

KSC-2012-1360

NASA Image and Video Library

2012-02-16

VANDENBERG AIR FORCE BASE, Calif. -- NuSTAR’s X-ray telescope is visible during the solar array deployment test at Vandenberg Air Force Base's processing facility in California. The Pegasus will launch NASA's Nuclear Spectroscopic Telescope Array NuSTAR into space. After the rocket and spacecraft are processed at Vandenberg, they will be flown on the Orbital Sciences’ L-1011 carrier aircraft to the Ronald Reagan Ballistic Missile Defense Test Site at the Pacific Ocean’s Kwajalein Atoll for launch. The high-energy x-ray telescope will conduct a census for black holes, map radioactive material in young supernovae remnants, and study the origins of cosmic rays and the extreme physics around collapsed stars. For more information, visit science.nasa.gov/missions/nustar/. Photo credit: NASA/Randy Beaudoin, VAFB

KSC-2012-1358

NASA Image and Video Library

2012-02-16

VANDENBERG AIR FORCE BASE, Calif. -- As a technician monitors the solar array deployment test at Vandenberg Air Force Base's processing facility in California, NuSTAR’s X-ray telescope is visible. The Pegasus will launch NASA's Nuclear Spectroscopic Telescope Array NuSTAR into space. After the rocket and spacecraft are processed at Vandenberg, they will be flown on the Orbital Sciences’ L-1011 carrier aircraft to the Ronald Reagan Ballistic Missile Defense Test Site at the Pacific Ocean’s Kwajalein Atoll for launch. The high-energy x-ray telescope will conduct a census for black holes, map radioactive material in young supernovae remnants, and study the origins of cosmic rays and the extreme physics around collapsed stars. For more information, visit science.nasa.gov/missions/nustar/. Photo credit: NASA/Randy Beaudoin, VAFB

KSC-2012-1359

NASA Image and Video Library

2012-02-16

VANDENBERG AIR FORCE BASE, Calif. -- As a technician monitors the solar array deployment test at Vandenberg Air Force Base's processing facility in California, NuSTAR’s X-ray telescope is visible. The Pegasus will launch NASA's Nuclear Spectroscopic Telescope Array NuSTAR into space. After the rocket and spacecraft are processed at Vandenberg, they will be flown on the Orbital Sciences’ L-1011 carrier aircraft to the Ronald Reagan Ballistic Missile Defense Test Site at the Pacific Ocean’s Kwajalein Atoll for launch. The high-energy x-ray telescope will conduct a census for black holes, map radioactive material in young supernovae remnants, and study the origins of cosmic rays and the extreme physics around collapsed stars. For more information, visit science.nasa.gov/missions/nustar/. Photo credit: NASA/Randy Beaudoin, VAFB

ISS-based Development of Elements and Operations for Robotic Assembly of A Space Solar Power Collector

NASA Technical Reports Server (NTRS)

Valinia, Azita; Moe, Rud; Seery, Bernard D.; Mankins, John C.

2013-01-01

We present a concept for an ISS-based optical system assembly demonstration designed to advance technologies related to future large in-space optical facilities deployment, including space solar power collectors and large-aperture astronomy telescopes. The large solar power collector problem is not unlike the large astronomical telescope problem, but at least conceptually it should be easier in principle, given the tolerances involved. We strive in this application to leverage heavily the work done on the NASA Optical Testbed Integration on ISS Experiment (OpTIIX) effort to erect a 1.5 m imaging telescope on the International Space Station (ISS). Specifically, we examine a robotic assembly sequence for constructing a large (meter diameter) slightly aspheric or spherical primary reflector, comprised of hexagonal mirror segments affixed to a lightweight rigidizing backplane structure. This approach, together with a structured robot assembler, will be shown to be scalable to the area and areal densities required for large-scale solar concentrator arrays.

-V2 plane on the Hubble Space Telescope

NASA Image and Video Library

2002-03-03

STS109-E-5104 (3 March 2002) --- The Hubble Space Telescope is seen in the cargo bay of the Space Shuttle Columbia. Each present set of solar array panels will be replaced during one of the space walks planned for the coming week. The crew aimed various cameras, including the digital still camera used for this frame, out the shuttle's aft flight deck windows to take a series of survey type photos, the first close-up images of the telescope since December of 1999.

-V2 plane on the Hubble Space Telescope

NASA Image and Video Library

2002-03-03

STS109-E-5102 (3 March 2002) --- The Hubble Space Telescope is seen in the cargo bay of the Space Shuttle Columbia. Each present set of solar array panels will be replaced during one of the space walks planned for the coming week. The crew aimed various cameras, including the digital still camera used for this frame, out the shuttle's aft flight deck windows to take a series of survey type photos, the first close-up images of the telescope since December of 1999.

Digital solar edge tracker for the Halogen Occultation Experiment

NASA Technical Reports Server (NTRS)

Mauldin, L. E., III; Moore, A. S.; Stump, C. W.; Mayo, L. S.

1987-01-01

The optical and electronic design of the Halogen Occultation Experiment (Haloe) elevation sun sensor is described. The Haloe instrument is a gas-correlation radiometer now being developed at NASA Langley for the Upper Atmosphere Research Satellite. The system uses a Galilean telescope to form a solar image on a linear silicon photodiode array. The array is a self-scanned monolithic CCD. The addresses of both solar edges imaged on the array are used by the control/pointing system to scan the Haloe science instantaneous field of view (IFOV) across the vertical solar diameter during instrument calibration and then to maintain the science IFOV 4 arcmin below the top edge during the science data occultation event. Vertical resolution of 16 arcsec and a radiometric dynamic range of 100 are achieved at the 700-nm operating wavelength. The design provides for loss of individual photodiode elements without loss of angular tracking capability.

Strategies on solar observation of Atacama Large Millimeter/submillimeter Array (ALMA) band-1 receiver

NASA Astrophysics Data System (ADS)

Chiong, Chau-Ching; Chiang, Po-Han; Hwang, Yuh-Jing; Huang, Yau-De

2016-07-01

ALMA covering 35-950 GHz is the largest existing telescope array in the world. Among the 10 receiver bands, Band-1, which covers 35-50 GHz, is the lowest. Due to its small dimension and its time-variant frequency-dependent gain characteristics, current solar filter located above the cryostat cannot be applied to Band-1 for solar observation. Here we thus adopt new strategies to fulfill the goals. Thanks to the flexible dc biasing scheme of the HEMT-based amplifier in Band-1 front-end, bias adjustment of the cryogenic low noise amplifier is investigated to accomplish solar observation without using solar filter. Large power handling range can be achieved by the de-tuning bias technique with little degradation in system performance.

Electrical performance comparison BSFR-/bifacial solar cell array

NASA Astrophysics Data System (ADS)

Hoffmann, U.; Reissmann, F.

1986-11-01

Conventional and bifacial solar arrays were compared on subsystem level using the Space Telescope-solar array mission as reference. Calculations show that the bifacial solar cell has a performance advantage of 18 to 21 percent. This is due to a 5 C average lower temperature of the bifacial cell at the same orbit conditions; the rearside albedo irradiation of 86 to 170 W/sqm (average of 180 deg and 0 deg orbit orientation respectively); and the fact that the temperature difference between the hot case (satellite between Earth and Sun) and the cold case (before eclipse) is lower for the bifacial cell than for the BSFR cell. This lower difference has the advantage that the operation point for the bifacial cells is closer to maximum voltage point over the orbit. Resistivity of the bifacial solar cells against particle radiation, and absorptivity of front and rearside of the bifacial cell for infrared radiation must be verified. Statistical deviations of the albedo intensity and spectrum are not known.

Uniting of NuSTAR Spacecraft and Rocket

NASA Image and Video Library

2012-02-23

Inside an environmental enclosure at Vandenberg Air Force Base processing facility in California, solar panels line the sides of NASA Nuclear Spectroscopic Telescope Array NuSTAR, which was just joined to the Orbital Sciences Pegasus XL rocket.

Design and analysis of optical systems for the Stanford/MSFC Multi-Spectral Solar Telescope Array

NASA Astrophysics Data System (ADS)

Hadaway, James B.; Johnson, R. Barry; Hoover, Richard B.; Lindblom, Joakim F.; Walker, Arthur B. C., Jr.

1989-07-01

This paper reports on the design and the theoretical ray trace analysis of the optical systems which will comprise the primary imaging components for the Stanford/MSFC Multi-Spectral Solar Telescope Array (MSSTA). This instrument is being developed for ultra-high resolution investigations of the sun from a sounding rocket. Doubly reflecting systems of sphere-sphere, ellipsoid-sphere (Dall-Kirkham), paraboloid-hyperboloid (Cassegrain), and hyperboloid-hyperboloid (Ritchey-Chretien) configurations were analyzed. For these mirror systems, ray trace analysis was performed and through-focus spot diagrams, point spread function plots, and geometrical and diffraction MTFs were generated. The results of these studies are presented along with the parameters of the Ritchey-Chretien optical system selected for the MSSTA flight. The payload, which incorporates seven of these Ritchey-Chretien systems, is now being prepared for launch in late September 1989.

KSC-01pp1760

NASA Image and Video Library

2001-11-29

KENNEDY SPACE CENTER, Fla. -- Fully unwrapped, the Advanced Camera for Surveys, which is suspended by an overhead crane, is checked over by workers. Part of the payload on the Hubble Space Telescope Servicing Mission, STS-109, the ACS will increase the discovery efficiency of the HST by a factor of ten. It consists of three electronic cameras and a complement of filters and dispersers that detect light from the ultraviolet to the near infrared (1200 - 10,000 angstroms). The ACS was built through a collaborative effort between Johns Hopkins University, Goddard Space Flight Center, Ball Aerospace Corporation and Space Telescope Science Institute. Tasks for the mission include replacing Solar Array 2 with Solar Array 3, replacing the Power Control Unit, removing the Faint Object Camera and installing the ACS, installing the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System, and installing New Outer Blanket Layer insulation on bays 5 through 8. Mission STS-109 is scheduled for launch Feb. 14, 2002

Design and analysis of optical systems for the Stanford/MSFC Multi-Spectral Solar Telescope Array

NASA Technical Reports Server (NTRS)

Hadaway, James B.; Johnson, R. Barry; Hoover, Richard B.; Lindblom, Joakim F.; Walker, Arthur B. C., Jr.

1989-01-01

This paper reports on the design and the theoretical ray trace analysis of the optical systems which will comprise the primary imaging components for the Stanford/MSFC Multi-Spectral Solar Telescope Array (MSSTA). This instrument is being developed for ultra-high resolution investigations of the sun from a sounding rocket. Doubly reflecting systems of sphere-sphere, ellipsoid-sphere (Dall-Kirkham), paraboloid-hyperboloid (Cassegrain), and hyperboloid-hyperboloid (Ritchey-Chretien) configurations were analyzed. For these mirror systems, ray trace analysis was performed and through-focus spot diagrams, point spread function plots, and geometrical and diffraction MTFs were generated. The results of these studies are presented along with the parameters of the Ritchey-Chretien optical system selected for the MSSTA flight. The payload, which incorporates seven of these Ritchey-Chretien systems, is now being prepared for launch in late September 1989.

Advance on solar instrumentation in China

NASA Astrophysics Data System (ADS)

Yan, Yihua

2015-08-01

The solar observing facilities in China are introduced with the emphasis on the development in recent years and future plans for both ground and space-based solar instrumentations. The recent solar instruments are as follows: A new generation Chinese Spectral Radioreliograph (CSRH) has been constructed at Mingantu Observing Station in Zhengxiangbaiqi, inner Mongolia of China since 2013 and is in test observations now. CSRH has two arrays with 40 × 4.5 m and 60 × 2 m parabolic antennas covering 0.4-2 GHz and 2-15 GHz frequency range. CSRH is renamed as MUSER (Mingantu Ultrawide Spectral Radiheliograph) after its accomplishment. A new 1 m vacuum solar telescope (NVST) has been installed in 2010 at Fuxian lake, 60 km away from Kunming, Yunana. At present it is the best seeing place in China. A new telescope called ONSET (Optical and NIR Solar Eruption Tracer) has been established at the same site as NVST in 2011. ONSET has been put into operation since 2013. For future ground-based plans, Chinese Giant Solar Telescope (CGST) with spatial resolution equivalent to 8m and effective area of 5m full-aperture telescope has been proposed and was formally listed into the National Plans of Major Science & Technology Infrastructures in China. The pre-study and site survey for CGST have been pursued. A 1-meter mid-infrared telescope for precise measurement of the solar magnetic field has been funded by NSFC in 2014 as a national major scientific instrument development project. This project will develop the first mid-infrared solar magnetic observation instrument in the world aiming at increasing the precision of the transverse magnetic field measurement by one order of magnitude. For future ground-based plans, we promote the Deep-space Solar Observatory (DSO) with 1-m aperture telescope to be formally funded. The ASO-S (an Advanced Space-based Solar Observatory) has been supported in background phase by Space Science Program as a small mission. Other related space solar projects have also been proposed to promote the solar-terrestrial research.

Trends in measurement of solar vector magnetic fields using the Zeeman effect

NASA Technical Reports Server (NTRS)

Harvey, J. W.

1985-01-01

Trends in spectropolarimetry as applied to the problem of Zeeman effect measurement are discussed. The use of detector arrays to improve observing efficiency is obtained. Which required new polarization modulation schemes that match the time required to read detector arrays. Another significant trend is narrowband filters, to improve angular and temporal coverage, and to Fourier transform spectrometers, to improve spectral coverage and precision. Low-polarization designs and improved methods for compensating instrumental polarization were developed. A requirement for high angular resolution suggests using adaptive optical devices to subdue the effects of bad seeing. The ultimate strategy to beat the seeing is to loft the telescope above the atmosphere such as is planned with a 30-cm telescope in 1985 and a 1250-cm telescope in 1990.

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.

Artist concept of Hubble Space Telescope (HST) orbiting Earth after deploy

NASA Image and Video Library

1990-04-05

This artist concept shows the Hubble Space Telescope (HST) in operational configuration orbiting the Earth after its deploy from Discovery, Orbiter Vehicle (OV) 103 during STS-31. The high gain antennas (HGAs) and solar arrays (SAs) have been extended. HST's aperature door is open as it views the universe from a vantage point above the Earth's atmosphere. View provided by the Marshall Space Flight Center (MSFC).

A New Era in Solar Thermal-IR Astronomy: the NSO Array Camera (NAC) on the McMath-Pierce Telescope

NASA Astrophysics Data System (ADS)

Ayres, T.; Penn, M.; Plymate, C.; Keller, C.

2008-09-01

The U.S. National Solar Observatory Array Camera (NAC) is a cryogenically cooled 1Kx1K InSb ``Aladdin" array that recently became operational at the McMath-Pierce facility on Kitt Peak, a high dry site in the southwest U.S. (Arizona). The new camera is similar to those already incorporated into instruments on nighttime telescopes, and has unprecedented sensitivity, low noise, and excellent cosmetics compared with the Amber Engineering (AE) device it replaces. (The latter was scavenged from a commercial surveillance camera in the 1990's: only 256X256 format, high noise, and annoying flatfield structure). The NAC focal plane is maintained at 30 K by a mechanical closed-cycle helium cooler, dispensing with the cumbersome pumped--solid-N2 40 K system used previously with the AE camera. The NAC linearity has been verified for exposures as short as 1 ms, although latency in the data recording holds the maximum frame rate to about 8 Hz (in "streaming mode"). The camera is run in tandem with the Infrared Adaptive Optics (IRAO) system. Utilizing a 37-actuator deformable mirror, IRAO can--under moderate seeing conditions--correct the telescope image to the diffraction limit longward of 2.3 mu (if a suitable high contrast target is available: the IR granulation has proven too bland to reliably track). IRAO also provides fine control over the solar image for spatial scanning in long-slit mode with the 14 m vertical "Main" spectrograph (MS). A 1'X1' area scan, with 0.5" steps orthogonal to the slit direction, requires less than half a minute, much shorter than p-mode and granulation evolution time scales. A recent engineering test run, in April 2008, utilized NAC/IRAO/MS to capture the fundamental (4.6 mu) and first-overtone (2.3 mu) rovibrational bands of CO, including maps of quiet regions, drift scans along the equatorial limbs (to measure the off-limb molecular emissions), and imaging of a fortuitous small sunspot pair, a final gasp, perhaps, of Cycle 23. Future work with the NAC will emphasize pathfinding toward the next generation of IR imaging spectrometers for the Advanced Technology Solar Telescope, whose 4 m aperture finally will bring sorely needed high spatial resolution to daytime infrared astronomy. In the meantime, the NAC is available to qualified solar physicists from around the world to conduct forefront research in the 1-5 mu region, on the venerable--but infrared friendly--McMath-Pierce telescope.

Solar Polarimetry: Proceedings of the National Solar Observatory/ Sacramento Peak Summer Workshop 11th Held in Sunspot, New Mexico on 27-31 August 1990

DTIC Science & Technology

1991-01-01

test at Arosa A,,t rphys- ical Observatory of the ETH Zdrich. Two beam splitters are positioned behind the mcdulat(r parkac’e if three CCD array sensors...data obtained with the Horizontal Telescope of the Arosa Astrophysical Observatory (HAT). The latter consist of simultaneous recordings of the Stokes

Hubble Space Telescope (HST) above OV-103's PLB during STS-31 deployment

NASA Image and Video Library

1990-04-25

The Hubble Space Telescope (HST) is raised above the payload bay (PLB) in low hover position during STS-31 checkout and pre-deployment procedures aboard Discovery, Orbiter Vehicle (OV) 103. Stowed along the HST Support System Module (SSM) are the high gain antenna (HGA) (center) and the two solar arrays (one either side). In the background are the orbital maneuvering system (OMS) pods and the Earth's surface.

Hubble Space Telescope Deploy, Cuba, Bahamas and Gulf of Mexico

NASA Image and Video Library

1990-04-29

STS031-151-010 (25 April 1990) --- The Hubble Space Telescope (HST), still in the grasp of Discovery's Remote Manipulator System (RMS), is backdropped over Cuba and the Bahama Islands. In this scene, it has yet to have deployment of its solar array panels and its high gain antennae. This scene was captured with a large format Aero Linhof camera used by several previous flight crews to record Earth scenes.

STS-31 pre-deployment checkout of the Hubble Space Telescope (HST) on OV-103

NASA Image and Video Library

1990-04-25

The Hubble Space Telescope (HST), grappled by Discovery's, Orbiter Vehicle (OV) 103's, remote manipulator system (RMS), is oriented in a 90 degree pitch position during STS-31 pre-deployment checkout procedures. The solar array (SA) panel (center) and high gain antennae (HGA) (on either side) are stowed along the Support System Module (SSM) forward shell prior to deployment. The sun highlights HST against the blackness of space.

Solar Simulation for the CREST Preflight Thermal-Vacuum Test at B-2

NASA Technical Reports Server (NTRS)

Ziemke, Robert A.

2013-01-01

In June 2011, the multi-university sponsored Cosmic Ray Electron Synchrotron Telescope (CREST) has undergone thermal-vacuum qualification testing at the NASA Glenn Research Center (GRC), Plum Brook Station, Sandusky, Ohio. The testing was performed in the B- 2 Space Propulsion Facility vacuum chamber. The CREST was later flown over the Antarctic region as the payload of a stratospheric balloon. Solar simulation was provided by a system of planar infrared lamp arrays specifically designed for CREST. The lamp arrays, in conjunction with a liquid-nitrogen-cooled cryoshroud, achieved the required thermal conditions for the qualification tests. This report focuses on the design and analysis of the planar arrays based on first principles. Computational spreadsheets are included in the report.

Chromospheric and Coronal Structure of Polar Plumes. 1; Magnetic Structure and Radiative Energy Balance

NASA Technical Reports Server (NTRS)

Allen, Maxwell J.; Oluseyi, Hakeem M.; Walker, Arthur B. C.; Hoover, Richard B.; Barbee, Troy W., Jr.

1997-01-01

The Multi-Spectral Solar Telescope Array (MSSTA), a rocket-borne solar observatory, was successfully launched from White Sands Missile Range, New Mexico, on May 13, 1991 at 19:05 UT. The telescope systems onboard the MSSTA obtained several full disk solar images in narrow bandpasses centered around strong soft X-ray, EUV, and FUV emission lines. Each telescope was designed to be sensitive to the coronal plasmas at a particular temperature, for seven temperatures ranging from 20,000 K to 4,000,000 K. We report here on the images obtained during the initial flight of the MSSTA, and on the chromospheric and coronal structure of polar plumes observed over both poles of the Sun. We have also co-aligned the MSSTA images with Kitt Peak magnetograms taken on the same day. We are able to positively identify the magnetic structures underlying the polar plumes we analyze as unipolar. We discuss the plume observations and present a radiative energy balance model derived from them.

Testing space weather connections in the solar system

NASA Astrophysics Data System (ADS)

Grison, B.; Souček, J.; Krupař, V.; Píša, D.; Santolík, O.; Taubenschuss, U.; Němec, F.

2017-09-01

This study aims at testing and validating tools for prediction of the impact of solar events in the vicinity of inner and outer solar system planets using in-situ spacecraft data (primarily MESSENGER, STEREO and ACE, but also VEX and Cassini), remote Jovian observations (Hubble telescope, Nançay decametric array), existing catalogues (HELCATS and Tao et al. (2005)) and the tested propagating models (the ICME radial propagation tool of the CDPP and the 1-D MHD code propagation model presented in Tao et al. (2005)).

SKYLAB 1 SOLAR CELL ARRAY INSTALLATION IN VAB

NASA Technical Reports Server (NTRS)

1972-01-01

One of Skylab 1's solar cell arrays installed on the orbital space station in High Bay 2 of the Vehicle Assembly Building today. Skylab 2 in High Bay 1 in visible in the background. Each of the two solar cell arrays on the space station that will be deployed in orbit, is designed to provide 10,500 watts of power at 55 degrees centigrade while in the sunlight portion of each orbit. All power needed to operate the station and the Apollo Telescope mount will be taken from the arrays. The remainder of the power generated will be diverted to battery chargers which will keep the batteries at full charge and ready for use while the orbiting spacecraft cluster is in the Earth's shadow. Each array will have almost 1,177 square feet of surface area to turn sunlight into electrical power. Skylab 1 is schedule for launch April 30, 1973 and Skylab 2, carrying the astronauts Conrad, Kerwin and Weitz to dock with the space station and enter it to live and work for 28 days, will be launched a day later.

Getting NuSTAR on target: predicting mast motion

NASA Astrophysics Data System (ADS)

Forster, Karl; Madsen, Kristin K.; Miyasaka, Hiromasa; Craig, William W.; Harrison, Fiona A.; Rana, Vikram R.; Markwardt, Craig B.; Grefenstette, Brian W.

2016-07-01

The Nuclear Spectroscopic Telescope Array (NuSTAR) is the first focusing high energy (3-79 keV) X-ray observatory operating for four years from low Earth orbit. The X-ray detector arrays are located on the spacecraft bus with the optics modules mounted on a flexible mast of 10.14m length. The motion of the telescope optical axis on the detectors during each observation is measured by a laser metrology system and matches the pre-launch predictions of the thermal flexing of the mast as the spacecraft enters and exits the Earths shadow each orbit. However, an additional motion of the telescope field of view was discovered during observatory commissioning that is associated with the spacecraft attitude control system and an additional flexing of the mast correlated with the Solar aspect angle for the observation. We present the methodology developed to predict where any particular target coordinate will fall on the NuSTAR detectors based on the Solar aspect angle at the scheduled time of an observation. This may be applicable to future observatories that employ optics deployed on extendable masts. The automation of the prediction system has greatly improved observatory operations efficiency and the reliability of observation planning.

Getting NuSTAR on Target: Predicting Mast Motion

NASA Technical Reports Server (NTRS)

Forster, Karl; Madsen, Kristin K.; Miyasaka, Hiroshima; Craig, William W.; Harrison, Fiona A.; Rana, Vikram R.; Markwardt, Craig B.; Grenfenstette, Brian W.

2017-01-01

The Nuclear Spectroscopic Telescope Array (NuSTAR) is the first focusing high energy (3-79 keV) X-ray observatory operating for four years from low Earth orbit. The X-ray detector arrays are located on the spacecraft bus with the optics modules mounted on a flexible mast of 10.14m length. The motion of the telescope optical axis on the detectors during each observation is measured by a laser metrology system and matches the pre-launch predictions of the thermal flexing of the mast as the spacecraft enters and exits the Earths shadow each orbit. However, an additional motion of the telescope field of view was discovered during observatory commissioning that is associated with the spacecraft attitude control system and an additional flexing of the mast correlated with the Solar aspect angle for the observation. We present the methodology developed to predict where any particular target coordinate will fall on the NuSTAR detectors based on the Solar aspect angle at the scheduled time of an observation. This may be applicable to future observatories that employ optics deployed on extendable masts. The automation of the prediction system has greatly improved observatory operations efficiency and the reliability of observation planning.

Integrated Dual Imaging Detector

NASA Technical Reports Server (NTRS)

Rust, David M.

1999-01-01

A new type of image detector was designed to simultaneously analyze the polarization of light at all picture elements in a scene. The integrated Dual Imaging detector (IDID) consists of a lenslet array and a polarizing beamsplitter bonded to a commercial charge coupled device (CCD). The IDID simplifies the design and operation of solar vector magnetographs and the imaging polarimeters and spectroscopic imagers used, for example, in atmosphere and solar research. When used in a solar telescope, the vector magnetic fields on the solar surface. Other applications include environmental monitoring, robot vision, and medical diagnoses (through the eye). Innovations in the IDID include (1) two interleaved imaging arrays (one for each polarization plane); (2) large dynamic range (well depth of 10(exp 5) electrons per pixel); (3) simultaneous readout and display of both images; and (4) laptop computer signal processing to produce polarization maps in field situations.

STS-31 pre-deployment checkout of the Hubble Space Telescope (HST) on OV-103

NASA Image and Video Library

1990-04-25

View taken through overhead window W7 aboard Discovery, Orbiter Vehicle (OV) 103, shows the Hubble Space Telescope (HST) grappled by the remote manipulator system (RMS) and held in a 90 degree pitch position against the blackness of space. The solar array (SA) panel (center) and the high gain antennae (HGA) (on either side) are visible along the Support System Module (SSM) forward shell prior to deployment during STS-31.

Hubble Space Telescope (HST) grappled by OV-103's RMS during STS-31 checkout

NASA Image and Video Library

1990-04-25

The Hubble Space Telescope (HST), grappled by Discovery's, Orbiter Vehicle (OV) 103's, remote manipulator system (RMS), is held in a pre-deployment position. During STS-31 checkout procedures, the solar array (SA) panels and the high gain antennae (HGA) will be deployed. The starboard SA (center) and the two HGA are stowed along side the Support System Module (SSM) forward shell. The sun highlights HST against the blackness of space.

KSC01pd1736

NASA Image and Video Library

2001-11-26

KENNEDY SPACE CENTER, Fla. -- A piece of equipment for Hubble Space Telescope Servicing mission is moved inside Hangar AE, Cape Canaveral. In the canister is the Advanced Camera for Surveys (ACS). The ACS will increase the discovery efficiency of the HST by a factor of ten. It consists of three electronic cameras and a complement of filters and dispersers that detect light from the ultraviolet to the near infrared (1200 - 10,000 angstroms). The ACS was built through a collaborative effort between Johns Hopkins University, Goddard Space Flight Center, Ball Aerospace Corporation and Space Telescope Science Institute. The goal of the mission, STS-109, is to service the HST, replacing Solar Array 2 with Solar Array 3, replacing the Power Control Unit, removing the Faint Object Camera and installing the ACS, installing the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System, and installing New Outer Blanket Layer insulation on bays 5 through 8. Mission STS-109 is scheduled for launch Feb. 14, 2002

KSC-01pp1758

NASA Image and Video Library

2001-11-29

KENNEDY SPACE CENTER, Fla. -- In Hangar A&E, workers watch as an overhead crane lifts the Advanced Camera for Surveys out of its transportation container. Part of the payload on the Hubble Space Telescope Servicing Mission, STS-109, the ACS will increase the discovery efficiency of the HST by a factor of ten. It consists of three electronic cameras and a complement of filters and dispersers that detect light from the ultraviolet to the near infrared (1200 - 10,000 angstroms). The ACS was built through a collaborative effort between Johns Hopkins University, Goddard Space Flight Center, Ball Aerospace Corporation and Space Telescope Science Institute. Tasks for the mission include replacing Solar Array 2 with Solar Array 3, replacing the Power Control Unit, removing the Faint Object Camera and installing the ACS, installing the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System, and installing New Outer Blanket Layer insulation on bays 5 through 8. Mission STS-109 is scheduled for launch Feb. 14, 2002

KSC01pd1735

NASA Image and Video Library

2001-11-26

KENNEDY SPACE CENTER, Fla. - A piece of equipment for Hubble Space Telescope Servicing mission arrives at Hangar AE, Cape Canaveral. Inside the canister is the Advanced Camera for Surveys (ACS). The ACS will increase the discovery efficiency of the HST by a factor of ten. It consists of three electronic cameras and a complement of filters and dispersers that detect light from the ultraviolet to the near infrared (1200 - 10,000 angstroms). The ACS was built through a collaborative effort between Johns Hopkins University, Goddard Space Flight Center, Ball Aerospace Corporation and Space Telescope Science Institute. The goal of the mission, STS-109, is to service the HST, replacing Solar Array 2 with Solar Array 3, replacing the Power Control Unit, removing the Faint Object Camera and installing the ACS, installing the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System, and installing New Outer Blanket Layer insulation on bays 5 through 8. Mission STS-109 is scheduled for launch Feb. 14, 2002

MS Linnehan checks airlock hatch on middeck

NASA Image and Video Library

2002-03-05

STS109-E-5602 (5 March 2002) --- Astronaut Richard M. Linnehan, mission specialist, checks the airlock hatch as two crewmates on the other side, equipped with extravehicular mobility units (EMU) space suits, start their extravehicular activity (EVA). On the previous day astronauts Linnehan and John M. Grunsfeld replaced the starboard solar array on the Hubble Space Telescope (HST). This day's space walk went on to see astronauts James H. Newman and Michael J. Massimino replace the port solar array. Grunsfeld's suit, scheduled for two more space walks, is temporarily stowed on the mid deck floor at right. The image was recorded with a digital still camera.

STS-109 Post Flight Presentation

NASA Astrophysics Data System (ADS)

2002-04-01

The STS-109 Post Flight presentation begins with Mission Specialists Nancy J. Currie, Michael J. Massimino, James H. Newman, and Richard M. Linnehan shown getting suited on launch day. Actual footage of the liftoff of the Space Shuttle Columbia is shown. Five spacewalks are performed to service the Hubble Space Telescope. Richard Linnehan and John Grunsfield are replacing solar arrays, connectors and power control units on the Hubble Space Telescope. Mission Specialist Nancy Currie will use Space Shuttle Columbia's robotic arm to grab the telescope, move it away from the orbiter and release it. A look at the coast of South America is also presented.

ASTRONAUT CHARLE CONRAD - SKYLAB II (M-114)

NASA Image and Video Library

1973-06-05

S73-27508 (6 June 1973) --- An artist's concept showing astronaut Charles Conrad Jr., Skylab 2 commander, attempting to free the solar array system wing on the Orbital Workshop during extravehicular activity at the Skylab 1 & 2 space station cluster in Earth orbit. The astronaut in the background is Joseph P. Kerwin, Skylab 2 science pilot. Here, Conrad is pushing up on the Beam Erection Tether (BET) to raise the stuck solar panel. The solar wing is only partially deployed; an aluminum strap is believed to be holding it down. Note the cut aluminum angle. Attach points for the BET are on the vent module of the solar array beam. The other end of the BET is attached to the "A" frame supporting the Apollo Telescope Mount (ATM) which is out of view. The aluminum strapping is to be out first, freeing the solar array beam. Then, if the beam does not automatically deploy, Conrad will attempt to help by pulling on the BET. The automatic openers may have become too cold to open without assistance. A deployed solar panel of the ATM is at upper left. The EVA is scheduled for Thursday, June 7th. This concept is by artist Paul Fjeld. Photo credit: NASA

The MEXART ips observations in route to the next solar maximum

NASA Astrophysics Data System (ADS)

Carrillo-Vargas, Armando; Gonzalez-Esparza, Americo; Andrade, Ernesto; Perez-Enriquez, Roman; Aguilar-Rodriguez, Ernesto; Casillas-Perez, Gilberto; Jeyakumar, Solai; Kurtz, Stanley; Sierra, Pablo; Vazquez, Samuel

We report the status of the Mexican Array Radio Telescope (MEXART) in preparation for the next solar maximum. During this epoch, the MEXART will be one of the four dedicated radio telescopes (with the ORT in India; STEL in Japan; and MWA in Australia) to track large-scale structures in the solar wind using the interplanetary scintillation (IPS) technique. This network of IPS observatories would produce, for the first time four g maps of the sky showing the size and shape of disturbances between the Sun and the Earth. We describe the operation and current observations of the first IPS radio sources at 140 MHz detected by the MEXART. These observations use a plane dipole array of 1024 elements (16 lines with 64 dipoles each one), feeding a Butler matrix of 16x16 ports. This system generates a 16 lobes at fixed declinations covering 120 degrees (from 40 degrees South to 80 degrees North). The beam fan uses the Earth's rotation to cover the whole sky. The observations that will be made with the network of observatories of interplanetary flashing will complement the observations of other observatories, instruments in situ, space probes, satellite, among others.

Large-field high-resolution mosaic movies

NASA Astrophysics Data System (ADS)

Hammerschlag, Robert H.; Sliepen, Guus; Bettonvil, Felix C. M.; Jägers, Aswin P. L.; Sütterlin, Peter; Martin, Sara F.

2012-09-01

Movies with fields-of-view larger than normal for high-resolution telescopes will give a better understanding of processes on the Sun, such as filament and active region developments and their possible interactions. New active regions can influence, by their emergence, their environment to the extent of possibly serving as an igniter of the eruption of a nearby filament. A method to create a large field-of-view is to join several fields-of-view into a mosaic. Fields are imaged quickly one after another using fast telescope-pointing. Such a pointing cycle has been automated at the Dutch Open Telescope (DOT), a high-resolution solar telescope located on the Canary Island La Palma. The observer can draw with the computer mouse the desired total field in the guider-telescope image of the whole Sun. The guider telescope is equipped with an H-alpha filter and electronic enhancement of contrast in the image for good visibility of filaments and prominences. The number and positions of the subfields are calculated automatically and represented by an array of bright points indicating the subfield centers inside the drawn rectangle of the total field on the computer screen with the whole-sun image. When the exposures start the telescope repeats automatically the sequence of subfields. Automatic production of flats is also programmed including defocusing and fast motion over the solar disk of the image field. For the first time mosaic movies were programmed from stored information on automated telescope motions from one field to the next. The mosaic movies fill the gap between whole-sun images with limited resolution of synoptic telescopes including space instruments and small-field high-cadence movies of high-resolution solar telescopes.

The Multi-Spectral Solar Telescope Array (MSSTA)

NASA Technical Reports Server (NTRS)

Walker, A. B. C., Jr.; Barbee, Troy W., Jr.; Hoover, Richard B.

1997-01-01

In 1987, our consortium pioneered the application of normal incidence multilayer X-ray optics to solar physics by obtaining the first high resolution narrow band, "thermally differentiated" images of the corona', using the emissions of the Fe IX/Fe X complex at ((lambda)lambda) approx. 171 A to 175 A, and He II Lyman (beta) at 256 A. Subsequently, we developed a rocket borne solar observatory, the Multi Spectral Solar Telescope Array (MSSTA) that pioneered multi-thermal imaging of the solar atmosphere, using high resolution narrow band X-ray, EUV and FUV optical systems. Analysis of MSSTA observations has resulted in four significant insights into the structure of the solar atmosphere: (1) the diameter of coronal loops is essentially constant along their length; (2) models of the thermal and density structure of polar plumes based on MSSTA observations have been shown to be consistent with the thesis that they are the source of high speed solar wind streams; (3) the magnetic structure of the footpoints of polar plumes is monopolar, and their thermal structure is consistent with the thesis that the chromosphere at their footpoints is heated by conduction from above; (4) coronal bright points are small loops, typically 3,500 - 20,000 km long (5 sec - 30 sec); their footpoints are located at the poles of bipolar magnetic structures that are are distinguished from other network elements by having a brighter Lyman a signature. Loop models derived for 26 bright points are consistent with the thesis that the chromosphere at their footpoints is heated by conduction from the corona.

X ray microscope/telescope test and alignment

NASA Technical Reports Server (NTRS)

Walker, Arthur B. C.; Hoover, Richard B.

1991-01-01

The tasks performed by the Center for Applied Optics (CAO) in support of the Normal Incidence Multilayer X-Ray Optics Program are detailed. The Multi-Spectral Solar Telescope Array (MSSTA) was launched on a Terrier-boosted Black Brant sounding rocket from White Sands Missile Range on 13 May 1991. High resolution images of the sun in the soft x ray to extreme ultraviolet (EUV) regime were obtained with normal-incidence Cassegrain, Ritchey-Chretien, and Herschelian telescopes mounted in the sounding rocket. MSSTA represents the first use of multilayer optics to study a very broad range of x ray and EUV solar emissions. Energy-selective properties of multilayer-coated optics allow distinct groups of emission lines to be isolated in the solar corona and transition region. Features of the near and far coronal structures including magnetic loops of plasmas, coronal plumes, coronal holes, faint structures, and cool prominences are visible in these images. MSSTA successfully obtained unprecedented information regarding the structure and dynamics of the solar atmosphere in the temperature range of 10(exp 4)-10(exp 7) K. The performance of the MSSTA has demonstrated a unique combination of ultra-high spatial resolution and spectral differentiation by use of multilayer optics.

STS-31 pre-deployment checkout of the Hubble Space Telescope (HST) on OV-103

NASA Image and Video Library

1990-04-25

During STS-31 checkout, the Hubble Space Telescope (HST) is held in a pre-deployment position by Discovery's, Orbiter Vehicle (OV) 103's, remote manipulator system (RMS). The view, taken from the crew cabin overhead window W7, shows the starboard solar array (SA) panel (center) and two high gain antennae (HGA) (on either side) stowed along side the Support System Module (SSM) forward shell. The sun highlights HST against the blackness of space.

HST deployed after repairs

NASA Image and Video Library

2002-03-09

STS109-E-5700 (9 March 2002) --- The Hubble Space Telescope, sporting new solar arrays and other important but less visible new hardware, begins its separation from the Space Shuttle Columbia. The STS-109 crew deployed the giant telescope at 4:04 a.m. CST (1004 GMT), March 9, 2002. Afterward, the seven crew members began to focus their attention to the trip home, scheduled for March 12. The STS-109 astronauts conducted five space walks to service and upgrade Hubble. This image was recorded with a digital still camera.

HST deployed after repairs

NASA Image and Video Library

2002-03-09

STS109-E-5704 (9 March 2002) --- The Hubble Space Telescope, sporting new solar arrays and other important but less visible new hardware, begins its separation from the Space Shuttle Columbia. The STS-109 crew deployed the giant telescope at 4:04 a.m. CST (1004 GMT), March 9, 2002. Afterward, the seven crew members began to focus their attention to the trip home, scheduled for March 12. The STS-109 astronauts conducted five space walks to service and upgrade Hubble. This image was recorded with a digital still camera.

HST deployed after repairs

NASA Image and Video Library

2002-03-09

STS109-E-5703 (9 March 2002) --- The Hubble Space Telescope, sporting new solar arrays and other important but less visible new hardware, begins its separation from the Space Shuttle Columbia. The STS-109 crew deployed the giant telescope at 4:04 a.m. CST (1004 GMT), March 9, 2002. Afterward, the seven crew members began to focus their attention to the trip home, scheduled for March 12. The STS-109 astronauts conducted five space walks to service and upgrade Hubble. This image was recorded with a digital still camera.

STS-37 Gamma Ray Observatory (GRO) grappled by RMS

NASA Image and Video Library

1991-04-07

Backdropped against the Earth's surface, the Gamma Ray Observatory (GRO) with its solar array (SA) panels deployed is grappled by the remote manipulator system (RMS) during STS-37 systems checkout. GRO's four complement instruments are visible: the Energetic Gamma Ray Experiment Telescope (EGRET) (at the bottom); the Imaging Compton Telescope (COMPTEL) (center); the Oriented Scintillation Spectrometer Experiment (OSSE) (top); and Burst and Transient Source Experiment (BATSE) (on four corners). The view was taken by STS-37 crew through an aft flight deck overhead window.

Around Marshall

NASA Image and Video Library

1983-08-10

One of the main components of the Hubble Space Telescope (HST) is the Solar Array Drive Electronics (SADE) system. This system interfaces with the Support System Module (SSM) for exchange of operational commands and telemetry data. SADE operates and controls the Solar Array Drive Mechanisms (SADM) for the orientation of the Solar Array Drive (SAD). It also monitors the position of the arrays and the temperature of the SADM. During the first HST servicing mission, the astronauts replaced the SADE component because of some malfunctions. This turned out to be a very challenging extravehicular activity (EVA). Two transistors and two diodes had been thermally stressed with the conformal coating discolored and charred. Soldered cornections became molten and reflowed between the two diodes. The failed transistors gave no indication of defective construction. All repairs were made and the HST was redeposited into orbit. Prior to undertaking this challenging mission, the orbiter's crew trained at Marshall Space Flight Center's (MSFC) Neutral Buoyancy Simulator (NBS) to prepare themselves for working in a low gravity environment. They also practiced replacing HST parts and exercised maneuverability and equipment handling. Pictured are crew members practicing on a space platform.

Study of Radio sources and interferences detected by MEXART

NASA Astrophysics Data System (ADS)

Villanueva Hernandez, P.; Gonzalez Esparza, J. A.; Carrillo, A.; Andrade, E.; Jeyacumar, S.; Kurtz, S.

2007-05-01

The Mexican Array Radio Telescope (MEXART) is a radio telescope that will perform studies of solar wind disturbances using the Interplanetary Scintillation (IPS) technique. The radiotelescope is its final calibration stage, and in this work we report two testings: the interference signals detected around the operation frequency, and the transit of the main radio sources detected by individual lines of 64 dipoles. These radio sources are: Sun, Casiopea, Crab nebula, Cygnus and Virgo. These testings allow us to know the response of the array elements in order to calibrate them. The final operation of the MEXART requires that the signal detected and transmitted by each East-West line of 64 dipoles arrives at the butler matrix (control room) with the same phase and amplitude.

Space Science

NASA Image and Video Library

1999-04-20

NASA's Space Optics Manufacturing Technology Center has been working to expand our view of the universe via sophisticated new telescopes. The Optics Center's goal is to develop low-cost, advanced space optics technologies for the NASA program in the 21st century, including the long-term goal of imaging Earth-like planets in distant solar systems. A segmented array of mirrors was designed by the Space Optics Manufacturing Technology Center for the solar concentrator test stand at the Marshall Space Flight Center (MSFC) for powering solar thermal propulsion engines. Each hexagon mirror has a spherical surface to approximate a parabolic concentrator when combined into the entire 18-foot diameter array. The aluminum mirrors were polished with a diamond turning machine that creates a glass-like reflective finish on metal. The precision fabrication machinery at the Space Optics Manufacturing Technology Center at MSFC can polish specialized optical elements to a world class quality of smoothness. This image shows optics physicist, Vince Huegele, examining one of the 144-segment hexagonal mirrors of the 18-foot diameter array at the MSFC solar concentrator test stand.

Space Science

NASA Image and Video Library

1999-04-20

NASA's Space Optics Manufacturing Technology Center has been working to expand our view of the universe via sophisticated new telescopes. The Optics Center's goal is to develop low-cost, advanced space optics technologies for the NASA program in the 21st century, including the long-term goal of imaging Earth-like planets in distant solar systems. A segmented array of mirrors was designed by the Space Optics Manufacturing Technology Center for solar the concentrator test stand at the Marshall Space Flight Center (MSFC) for powering solar thermal propulsion engines. Each hexagon mirror has a spherical surface to approximate a parabolic concentrator when combined into the entire 18-foot diameter array. The aluminum mirrors were polished with a diamond turning machine, that creates a glass-like reflective finish on metal. The precision fabrication machinery at the Space Optics Manufacturing Technology Center at MSFC can polish specialized optical elements to a world class quality of smoothness. This image shows optics physicist, Vince Huegele, examining one of the 144-segment hexagonal mirrors of the 18-foot diameter array at the MSFC solar concentrator test stand.

EVA 3 - Linnehan portrait

NASA Image and Video Library

2002-03-06

STS109-322-028 (6 March 2002) --- Astronaut Richard M. Linnehan, STS-109 mission specialist, participates in the third of five space walks to perform work on the Hubble Space Telescope (HST). Linnehan's sun shield reflects astronaut John M. Grunsfeld and the blue and white Earth's hemisphere as well as one of the telescope's new solar arrays. The third overall STS-109 extravehicular activity (EVA) marked the second of three for Linnehan and Grunsfeld, payload commander. On this particular walk, the two turned off the telescope in order to replace the power control unit or PCU--the heart of its power system. Grunsfeld took this photo with a 35mm camera.

STS-61 art concept of astronauts during HST servicing

NASA Image and Video Library

1993-11-12

S93-48826 (November 1993) --- This artist's rendition of the 1993 Hubble Space Telescope (HST) servicing mission shows astronauts installing the new Wide Field/Planetary Camera (WF/PC 2). The instruments to replace the original camera and contains corrective optics that compensate for the telescope's flawed primary mirror. During the 11-plus day mission, astronauts are also scheduled to install the Corrective Optics Space Telescope Axial Replacement (COSTAR) -- an optics package that focuses and routes light to the other three instruments aboard the observatory -- a new set of solar array panels, and other hardware and components. The artwork was done for JPL by Paul Hudson.

The possibility of gamma-ray astronomy measurements on the Russian segment of the International Space Station.

NASA Astrophysics Data System (ADS)

Fradkin, M. I.; Gorchakov, E. V.; Kaplin, V. A.; Kaplin, D. V.; Kurnosova, L. V.; Labenskij, A. G.; Runtso, M. F.; Topchiev, N. P.

The conditions required for gamma-ray astronomy measurements at energies of 10 - 1000 GeV by a gamma-ray telescope on the International Space Station are discussed. It is shown that the properties of the detected gamma rays can be determined accurately at 30 - 1000 GeV, even if the space station solar arrays fall in the aperture of the gamma-ray telescope. Measurements of the secondary gamma-ray spectrum using a ground-based model of the gamma-ray telescope have been carried out, and the resulting spectrum at energies of 1 - 100 GeV is presented.

Future Trends in Solar Radio Astronomy and Coronal Magnetic-Field Measurements

NASA Astrophysics Data System (ADS)

Fleishman, Gregory; Nita, Gelu; Gary, Dale

Solar radio astronomy has an amazingly rich, but yet largely unexploited, potential for probing the solar corona and chromosphere. Radio emission offers multiple ways of detecting and tracking electron beams, studying chromospheric and coronal thermal structure, plasma processes, particle acceleration, and measuring magnetic fields. To turn the mentioned potential into real routine diagnostics, two major components are needed: (1) well-calibrated observations with high spatial, spectral, and temporal resolutions and (2) accurate and reliable theoretical models and fast numerical tools capable of recovering the emission source parameters from the radio data. This report gives a brief overview of the new, expanded, and planned radio facilities, such as Expanded Owens Valley Solar Array (EOVSA), Jansky Very Large Array (JVLA), Chinese Solar Radio Heliograph (CSRH), Upgraded Siberian Solar Radio Telescope (USSRT), and Frequency Agile Solar Radiotelescope (FASR) with the emphasis on their ability to measure the coronal magnetic fields in active regions and flares. In particular, we emphasize the new tools for 3D modeling of the radio emission and forward fitting tools in development needed to derive the magnetic field data from the radio measurements.

Skylab

NASA Image and Video Library

1972-05-01

Technicians at NASA’s Marshall Space Flight Center check the wiring on a mechanical test article of the Apollo Telescope Mount (ATM) solar array. Four such arrays were joined in a cross to provide electric power for the ATM in Earth orbit. The deployment mechanism for extending the wing to the fully open position had just been tested when this photograph was taken. The array was suspended from beams riding on air bearings to closely simulate the weightless conditions under which it would be deployed in space. The wings are folded against the sides of the ATM for launch and are deployed by a scissors mechanism in Earth’s orbit.

Space Shuttle Projects

NASA Image and Video Library

1999-08-01

Designed by the crew members, the STS-103 emblem depicts the Space Shuttle Discovery approaching the Hubble Space Telescope (HST) prior to its capture and berthing. The purpose of the mission was to remove and replace some of the Telescope's older and out-of-date systems with newer, more reliable and more capable ones, and to make repairs to HST's exterior thermal insulation that had been damaged by more than nine years of exposure to the space environment. The horizontal and vertical lines centered on the Telescope symbolize the ability to reach and maintain a desired attitude in space, essential to the instrument's scientific operation. The preservation of this ability was one of the primary objectives of the mission. After the flight, the Telescope resumed its successful exploration of deep space and will continue to be used to study solar system objects, stars in the making, late phases of stellar evolution, galaxies and the early history of the universe. HST, as represented on this emblem was inspired by views from previous servicing missions, with its solar arrays illuminated by the Sun, providing a striking contrast with the blackness of space and the night side of Earth.

Kodak Mirror Assembly Tested at Marshall Space Flight Center

NASA Technical Reports Server (NTRS)

2003-01-01

This photo (rear view) is of one of many segments of the Eastman-Kodak mirror assembly being tested for the James Webb Space Telescope (JWST) project at the X-Ray Calibration Facility at Marshall Space Flight Center (MSFC). MSFC is supporting Goddard Space Flight Center (GSFC) in developing the JWST by taking numerous measurements to predict its future performance. The tests are conducted in a vacuum chamber cooled to approximate the super cold temperatures found in space. During its 27 years of operation, the facility has performed testing in support of a wide array of projects, including the Hubble Space Telescope (HST), Solar A, Chandra technology development, Chandra High Resolution Mirror Assembly and science instruments, Constellation X-Ray Mission, and Solar X-Ray Imager, currently operating on a Geostationary Operational Environment Satellite. The JWST is NASA's next generation space telescope, a successor to the Hubble Space Telescope, named in honor of NASA's second administrator, James E. Webb. It is scheduled for launch in 2010 aboard an expendable launch vehicle. It will take about 3 months for the spacecraft to reach its destination, an orbit of 940,000 miles in space.

Around Marshall

NASA Image and Video Library

2003-04-09

This photo (a frontal view) is of one of many segments of the Eastman-Kodak mirror assembly being tested for the James Webb Space Telescope (JWST) project at the X-Ray Calibration Facility at Marshall Space Flight Center (MSFC). MSFC is supporting Goddard Space Flight Center (GSFC) in developing the JWST by taking numerous measurements to predict its future performance. The tests are conducted in a vacuum chamber cooled to approximate the super cold temperatures found in space. During its 27 years of operation, the facility has performed testing in support of a wide array of projects, including the Hubble Space Telescope (HST), Solar A, Chandra technology development, Chandra High Resolution Mirror Assembly and science instruments, Constellation X-Ray Mission, and Solar X-Ray Imager, currently operating on a Geostationary Operational Environment Satellite. The JWST is NASA's next generation space telescope, a successor to the Hubble Space Telescope, named in honor of NASA's second administrator, James E. Webb. It is scheduled for launch in 2010 aboard an expendable launch vehicle. It will take about 3 months for the spacecraft to reach its destination, an orbit of 940,000 miles in space.

Planet detection and spectroscopy in visible light with a single aperture telescope and a nulling coronagraph

NASA Technical Reports Server (NTRS)

Shao, Michael; Serabyn, Eugene; Levine, Bruce Martin; Beichman, Charles; Liu, Duncan; Martin, Stefan; Orton, Glen; Mennesson, Bertrand; Morgan, Rhonda; Velusamy, Thangasamy;

Millimeter and hard x ray/gamma ray observations of solar flares during the June 1991 GRO campaign

NASA Technical Reports Server (NTRS)

Kundu, M. R.; White, S. M.; Gopalswamy, N.; Lim, J.

1992-01-01

We have carried out high-spatial-resolution millimeter observations of solar flares using the Berkeley-Illinois-Maryland Array (BIMA). At the present time, BIMA consists of only three elements, which is not adequate for mapping highly variable solar phenomena, but is excellent for studies of the temporal structure of flares at millimeter wavelengths at several different spatial scales. We present BIMA observations made during the Gamma Ray Observatories (GRO)/Solar Max 1991 campaign in Jun. 1991 when solar activity was unusually high. Our observations covered the period 8-9 Jun. 1991; this period overlapped the period 4-15 Jun. when the Compton Telescope made the Sun a target of opportunity because of the high level of solar activity.

STS-109 MS Newman and Massimino in airlock after EVA

NASA Image and Video Library

2002-03-05

STS109-326-031 (5 March 2002) --- The broad smiles of astronauts Michael J. Massimino (left) and James H. Newman reflect the success of their just-completed lengthy space walk designed to finish the replacement of the solar arrays on the Hubble Space Telescope (HST). A day earlier, two other astronauts replaced one of sets of solar panels. The two are in the process of doffing their extravehicular mobility unit (EMU) space suits on the mid deck of the Space Shuttle Columbia.

A knowledge-based system for monitoring the electrical power system of the Hubble Space Telescope

NASA Technical Reports Server (NTRS)

Eddy, Pat

1987-01-01

The design and the prototype for the expert system for the Hubble Space Telescope's electrical power system are discussed. This prototype demonstrated the capability to use real time data from a 32k telemetry stream and to perform operational health and safety status monitoring, detect trends such as battery degradation, and detect anomalies such as solar array failures. This prototype, along with the pointing control system and data management system expert systems, forms the initial Telemetry Analysis for Lockheed Operated Spacecraft (TALOS) capability.

EVA 4 activity on Flight Day 7 to service the Hubble Space Telescope

NASA Image and Video Library

1997-02-17

S82-E-5606 (17 Feb. 1997) --- Astronaut Gregory J. Harbaugh at work on Hubble Space Telescope (HST), with the assistance of astronaut Joseph R. Tanner (out of frame) on Remote Manipulator System (RMS). After replacing the HST's Solar Array Drive Electronics (SADE), Harbaugh and Tanner replaced the Magnetic Sensing System (MSS) protective lids with new, permanent covers; and they installed pre-cut insulation pieces to correct tears in the HST's protective covering caused by temperature changes in space. This view was taken with an Electronic Still Camera (ESC).

KSC-08pd0783

NASA Image and Video Library

2008-03-21

CAPE CANAVERAL, Fla. --- In the Astrotech payload processing facility, the mechanism on NASA's Gamma-Ray Large Area Space Telescope, or GLAST, solar arrays has been released. The telescope will launch aboard a Delta II rocket May 16 from Launch Pad 17-B on Cape Canaveral Air Force Station. A powerful space observatory, the GLAST will explore the most extreme environments in the universe, and answer questions about supermassive black hole systems, pulsars and the origin of cosmic rays. It also will study the mystery of powerful explosions known as gamma-ray bursts. Photo credit: NASA/Jim Grossmann

KSC-08pd0765

NASA Image and Video Library

2008-03-20

KENNEDY SPACE CENTER, FLA. - In the Astrotech payload processing facility, one of twin solar arrays is positioned on NASA's Gamma-Ray Large Area Space Telescope, or GLAST. The telescope will launch aboard a Delta II rocket May 16 from Launch Pad 17-B on Cape Canaveral Air Force Station. A powerful space observatory, the GLAST will explore the most extreme environments in the universe, and answer questions about supermassive black hole systems, pulsars and the origin of cosmic rays. It also will study the mystery of powerful explosions known as gamma-ray bursts. Photo credit: NASA/Chris Rhodes

The Virtual Earth-Solar Observatory of the SCiESMEX

NASA Astrophysics Data System (ADS)

De la Luz, V.; Gonzalez-Esparza, A.; Cifuentes-Nava, G.

2015-12-01

The Mexican Space Weather Service (SCiESMEX, http://www.sciesmex.unam.mx) started operations in October 2014. The project includes the Virtual Earth-Solar Observatory (VESO, http://www.veso.unam.mx). The VESO is a improved project wich objetive is integrate the space weather instrumentation network from the National Autonomous University of Mexico (UNAM). The network includes the Mexican Array Radiotelescope (MEXART), the Callisto receptor (MEXART), a Neutron Telescope, a Cosmic Ray Telescope. the Schumann Antenna, the National Magnetic Service, and the mexican GPS network (TlalocNet). The VESO facility is located at the Geophysics Institute campus Michoacan (UNAM). We offer the service of data store, real-time data, and quasi real-time data. The hardware of VESO includes a High Performance Computer (HPC) dedicated specially to big data storage.

Optical and IR applications in astronomy and astrophysics

NASA Astrophysics Data System (ADS)

McLean, Ian S.

2009-06-01

The set comprising silicon charge-coupled devices, low band-gap infrared arrays and bolometer arrays provide astronomers with position-sensitive photon detectors from the X-ray to the sub-mm. In recent years the most significant advances have occurred in the near-infrared part of the spectrum because not only have the detector formats caught up with those of charge-coupled device (CCDs) but also because the advent of adaptive optics (AO) has meant that the very largest telescopes can achieve their diffraction limit in the near-infrared. Thus infrared cameras, spectrometers and hybrid instruments that measure spatial and spectral information simultaneously are now commanding the greatest attention on telescopes from 6.5 to 10 m in effective aperture. Scientific applications of these new infrared instruments span everything from the search for nearby solar systems to the orbital motions of stars about the massive black hole at the center of the Milky Way, and studies of the first galaxies to form in the high redshift Universe. Background, principles and applications of infrared array detectors to astronomy and astrophysics will be discussed with particular emphasis on work at the W.M. Keck 10-m telescope on Mauna Kea, Hawaii.

Degradation of FEP thermal control materials returned from the Hubble Space Telescope

NASA Technical Reports Server (NTRS)

Zuby, Thomas M.; Degroh, Kim K.; Smith, Daniela C.

1995-01-01

After an initial 3.6 years of space flight, the Hubble Space Telescope was serviced through a joint effort with the NASA and the European Space Agency. Multi-layer insulation (MLI) was retrieved from the electronics boxes of the two magnetic sensing systems (MSS), also called the magnetometers, and from the returned solar array (SA-I) drive arm assembly. The top layer of each MLI assembly is fluorinated ethylene propylene (FEP, a type of Teflon). Dramatic changes in material properties were observed when comparing areas of high solar fluence to areas of low solar fluence. Cross sectional analysis shows atomic oxygen (AO) erosion values up to 25.4 mu m (1 mil). Greater occurrences of through-thickness cracking and surface microcracking were observed in areas of high solar exposure. Atomic force microscopy (AFM) showed increases in surface microhardness measurements with increasing solar exposure. Decreases in FEP tensile strength and elongation were measured when compared to non-flight material. Erosion yield and tensile results are compared with FEP data from the Long Duration Exposure Facility. AO erosion yield data, solar fluence values, contamination, micrometeoroid or debris impact sites, and optical properties are presented.

Operation of the University of Hawaii 2.2M telescope on Mauna Kea

NASA Technical Reports Server (NTRS)

Hall, Donald N. B.

1991-01-01

NASA's planetary astronomy program provides part of the funding for the 2.2 meter telescope. The parameters for time on the telescope are laid out. A major instrumental highlight has been the commissioning of a 256 x 256 near infrared camera which uses a Rockwell NICMOS-3 array. At the f/10 focus, image scales of 0.37 and 0.75 arcsec/pixel are available. A new, high quantum efficiency Tektronix 1024 x 1024 CCD saw first light on the telescope in 1991, and was available regularly from April 1991. Data from both of these detectors are transmitted directly to the Sun workstation for immediate analysis by the observers. The autoguider software was enhanced to permit guided tracking on objects have nonsideral motions (i.e., solar system objects).

Around Marshall

NASA Image and Video Library

1983-08-10

One of the main components of the Hubble Space Telescope (HST) is the Solar Array Drive Electronics (SADE) system. This system interfaces with the Support System Module (SSM) for exchange of operational commands and telemetry data. SADE operates and controls the Solar Array Drive Mechanisms (SADM) for the orientation of the Solar Array Drive (SAD). It also monitors the position of the arrays and the temperature of the SADM. During the first HST servicing mission, the astronauts replaced the SADE component because of some malfunctions. This turned out to be a very challenging extravehicular activity (EVA). Two transistors and two diodes had been thermally stressed with the conformal coating discolored and charred. Soldered cornections became molten and reflowed between the two diodes. The failed transistors gave no indication of defective construction. All repairs were made and the HST was redeposited into orbit. Prior to undertaking this challenging mission, the orbiter's crew trained at Marshall Space Flight Center's (MSFC) Neutral Buoyancy Simulator (NBS) to prepare themselves for working in a low gravity environment. They also practiced replacing HST parts and exercised maneuverability and equipment handling. Pictured is an astronaut practicing climbing a space platform that was necessary in making repairs on the HST.

Neutral Buoyancy Simulator - SADE NBS Test

NASA Technical Reports Server (NTRS)

1983-01-01

One of the main components of the Hubble Space Telescope (HST) is the Solar Array Drive Electronics (SADE) system. This system interfaces with the Support System Module (SSM) for exchange of operational commands and telemetry data. SADE operates and controls the Solar Array Drive Mechanisms (SADM) for the orientation of the Solar Array Drive (SAD). It also monitors the position of the arrays and the temperature of the SADM. During the first HST servicing mission, the astronauts replaced the SADE component because of some malfunctions. This turned out to be a very challenging extravehicular activity (EVA). Two transistors and two diodes had been thermally stressed with the conformal coating discolored and charred. Soldered cornections became molten and reflowed between the two diodes. The failed transistors gave no indication of defective construction. All repairs were made and the HST was redeposited into orbit. Prior to undertaking this challenging mission, the orbiter's crew trained at Marshall Space Flight Center's (MSFC) Neutral Buoyancy Simulator (NBS) to prepare themselves for working in a low gravity environment. They also practiced replacing HST parts and exercised maneuverability and equipment handling. Pictured is an astronaut practicing climbing a space platform that was necessary in making repairs on the HST.

Neutral Buoyancy Simulator-NB50B-SADE Training Exercises

NASA Technical Reports Server (NTRS)

1983-01-01

One of the main components of the Hubble Space Telescope (HST) is the Solar Array Drive Electronics (SADE) system. This system interfaces with the Support System Module (SSM) for exchange of operational commands and telemetry data. SADE operates and controls the Solar Array Drive Mechanisms (SADM) for the orientation of the Solar Array Drive (SAD). It also monitors the position of the arrays and the temperature of the SADM. During the first HST servicing mission, the astronauts replaced the SADE component because of some malfunctions. This turned out to be a very challenging extravehicular activity (EVA). Two transistors and two diodes had been thermally stressed with the conformal coating discolored and charred. Soldered cornections became molten and reflowed between the two diodes. The failed transistors gave no indication of defective construction. All repairs were made and the HST was redeposited into orbit. Prior to undertaking this challenging mission, the orbiter's crew trained at Marshall Space Flight Center's (MSFC) Neutral Buoyancy Simulator (NBS) to prepare themselves for working in a low gravity environment. They also practiced replacing HST parts and exercised maneuverability and equipment handling. Pictured are crew members practicing on a space platform.

Solar Simulation for the CREST Preflight Thermal-Vacuum Test at B-2

NASA Technical Reports Server (NTRS)

Ziemke, Robert A.

2012-01-01

In June 2011, the multi-university sponsored Cosmic Ray Electron Synchrotron Telescope (CREST) has undergone thermal-vacuum qualification testing at the NASA Glenn Research Center (GRC), Plum Brook Station, Sandusky, Ohio. The testing was performed in the B-2 Space Propulsion Facility vacuum chamber. The CREST was later flown over the Antarctic region as the payload of a stratospheric balloon. Solar simulation was provided by a system of planar infrared lamp arrays specifically designed for CREST. The lamp arrays, in conjunction with a liquid-nitrogen-cooled cold wall, achieved the required thermal conditions for the qualification tests. The following slides accompanied the presentation of the report entitled Solar Simulation for the CREST Preflight Thermal-Vacuum Test at B-2, at the 27th Aerospace Testing Seminar, October 2012. The presentation described the test article, the test facility capability, the solar simulation requirements, the highlights of the engineering approach, and the results achieved. The presentation was intended to generate interest in the report and in the B-2 test facility.

TESS Spacecraft Solar Panel Array Deployment Testing

NASA Image and Video Library

2018-02-21

Inside the Payload Hazardous Servicing Facility at the NASA's Kennedy Space Center in Florida, one of the solar panels is being deployed on the agency's Transiting Exoplanet Survey Satellite (TESS). Technicians are preparing to deploy the second solar array. The satellite is scheduled to launch atop a SpaceX Falcon 9 rocket from Space Launch Complex 40 at Cape Canaveral Air Force Station. TESS is the next step in NASA's search for planets outside our solar system, known as exoplanets. TESS is a NASA Astrophysics Explorer mission led and operated by MIT in Cambridge, Massachusetts, and managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Dr. George Ricker of MIT’s Kavli Institute for Astrophysics and Space Research serves as principal investigator for the mission. Additional partners include Orbital ATK, NASA’s Ames Research Center, the Harvard-Smithsonian Center for Astrophysics and the Space Telescope Science Institute. More than a dozen universities, research institutes and observatories worldwide are participants in the mission. NASA’s Launch Services Program is responsible for launch management.

Evaluation of Engineering Properties of AL-Li Alloy X2096-T8A3 Extrusion Products

NASA Technical Reports Server (NTRS)

Flom, Y.; Viens, M.; Wang, L.

1999-01-01

Mechanical, thermal fatigue and stress corrosion properties were determined for the two lots of Al-Li X2096-T8A3 extruded beams. Based on the test results, the beams were accepted as the construction material for fabrication of the Hubble Space Telescope new Solar Array Support Structure.

Determination and characterization of the Hubble Space Telescope pointing stability

NASA Technical Reports Server (NTRS)

Bradley, A. J.; Connor, C. T.; Del Toro, Y.; Andersen, G. C.; Bely, Pierre Y.; Decker, J.; Franz, O. G.; Wasserman, L. H.; Van Altena, William F.

1993-01-01

The Hubble Space Telescope (HST) was designed to maintian a pointing stability (jitter) of 0.007 arc seconds rms throughout every observing period, which can last from a few seconds to several orbits. On-orbit measurements indicate that the hardware excitation induced by the reaction wheels. gyros, high gain antennae, science instrument mechanisms and tape recorders are well within specifications. Unexpectedly, the solar arrays because the dominant source of jitter. Every passage through an orbital terminator produces vibrations which emanate from the solar arrays due to thermal effects, which affect the relative positional stability. Broadband frequencies centered about 0.11 and 0.65 Hz were detected in the frequency content of the vehicle jitter. On-board modifications to the control law have attenuated the disturbance torques and reduced the vehicle jitter close to specification. Replacement of the solar arrays in December, 1993, should eliminate the torque distubances. Astrometric science observations are extremely susceptible to corruption from vehicle jitter. The removal of vehicle jitter from astrometric Transfer function scans of binary stars is explained in detail. A binary star separation of 16 milli-seconds of arc has been achieved, a separation resolution of 10 to 12 milli-seconds of arc appears feasible, with a binary star magnitude of 9 m(sub V). The achievement of this resolution is in part due to vehicle jitter removal. Comparison of vehicle jitter measurements from the position path of the vehicle control law, or from the guiding Fine Guidance Sensors (FGS), are shown to be equivalent to approximately 0.001 arc second.

Determination and characterization of the Hubble Space Telescope pointing stability

NASA Astrophysics Data System (ADS)

Bradley, A. J.; Connor, C. T.; del Toro, Y.; Andersen, G. C.; Bely, Pierre Y.; Decker, J.; Franz, O. G.; Wasserman, L. H.; van Altena, William F.

The Hubble Space Telescope (HST) was designed to maintian a pointing stability (jitter) of 0.007 arc seconds rms throughout every observing period, which can last from a few seconds to several orbits. On-orbit measurements indicate that the hardware excitation induced by the reaction wheels. gyros, high gain antennae, science instrument mechanisms and tape recorders are well within specifications. Unexpectedly, the solar arrays because the dominant source of jitter. Every passage through an orbital terminator produces vibrations which emanate from the solar arrays due to thermal effects, which affect the relative positional stability. Broadband frequencies centered about 0.11 and 0.65 Hz were detected in the frequency content of the vehicle jitter. On-board modifications to the control law have attenuated the disturbance torques and reduced the vehicle jitter close to specification. Replacement of the solar arrays in December, 1993, should eliminate the torque distubances. Astrometric science observations are extremely susceptible to corruption from vehicle jitter. The removal of vehicle jitter from astrometric Transfer function scans of binary stars is explained in detail. A binary star separation of 16 milli-seconds of arc has been achieved, a separation resolution of 10 to 12 milli-seconds of arc appears feasible, with a binary star magnitude of 9 m(sub V). The achievement of this resolution is in part due to vehicle jitter removal. Comparison of vehicle jitter measurements from the position path of the vehicle control law, or from the guiding Fine Guidance Sensors (FGS), are shown to be equivalent to approximately 0.001 arc second.

Observations of Interplanetary Scintillation (IPS) Using the Mexican Array Radio Telescope (MEXART)

NASA Astrophysics Data System (ADS)

Mejia-Ambriz, J. C.; Villanueva-Hernandez, P.; Gonzalez-Esparza, J. A.; Aguilar-Rodriguez, E.; Jeyakumar, S.

2010-08-01

The Mexican Array Radio Telescope (MEXART) consists of a 64×64 (4096) full-wavelength dipole antenna array, operating at 140 MHz, with a bandwidth of 2 MHz, occupying about 9660 square meters (69 m × 140 m) ( http://www.mexart.unam.mx ). This is a dedicated radio array for Interplanetary Scintillation (IPS) observations located at latitude 19°48'N, longitude 101°41'W. We characterize the performance of the system. We report the first IPS observations with the instrument, employing a Butler Matrix (BM) of 16×16 ports, fed by 16 east - west lines of 64 dipoles (1/4 of the total array). The BM displays a radiation pattern of 16 beams at different declinations (from -48, to +88 degrees). We present a list of 19 strong IPS radio sources (having at least 3 σ in power gain) detected by the instrument. We report the power spectral analysis procedure of the intensity fluctuations. The operation of MEXART will allow us a better coverage of solar wind disturbances, complementing the data provided by the other, previously built, instruments.

History of Hubble Space Telescope (HST)

NASA Image and Video Library

1986-01-01

This photograph shows the Hubble Space Telescope (HST) flight article assembly with multilayer insulation, high gain anterna, and solar arrays in a clean room of the Lockheed Missile and Space Company. The HST is the first of NASA's great observatories and the most complex and sensitive optical telescope ever made. The purpose of the HST is to study the cosmos from a low-Earth orbit by placing the telescope in space, enabling astronomers to collect data that is free of the Earth's atmosphere. The HST was deployed from the Space Shuttle Discovery (STS-31 mission) into Earth orbit in April 1990. The Marshall Space Flight Center had overall responsibility for design, development, and construction of the HST. The Perkin-Elmer Corporation, in Danbury, Connecticut, developed the optical system and guidance sensors. The Lockheed Missile and Space Company, Sunnyvale, California, produced the protective outer shroud and spacecraft systems, and assembled and tested the finished telescope.

Preliminary result of the solar multi-conjugate adaptive optics for 1m new vacuum solar telescope

NASA Astrophysics Data System (ADS)

Zhang, Lanqiang; Kong, Lin; Bao, Hua; Zhu, Lei; Rao, Xuejun; Rao, Changhui

2016-07-01

Solar observation with high resolution in large field of view (FoV) is required for some solar active regions with the typical sizes of 1' to 3'. Conventional adaptive optics (AO) could not satisfy this demand because of the atmospheric anisoplanatism. Through compensating the turbulence in different heights, multi-conjugate adaptive optics (MCAO) has been proved to obtain a larger corrected FoV. A MCAO experimental system including a conventional 151-element AO system and a 37-element MCAO part is being developed. The MCAO part contains a 37-element deformable mirror conjugated into the 2km to 5km height and a multi-direction Shack-Hartmann wavefront sensor (MD-SHWFS) with 7×7 subaperture array and 60 arcsec FoV, the frame rate of the MD-SHWFS is up to 840Hz. Three-dimensional (3-D) wavefront sensing utilizing atmospheric tomography had been validated by solar observation. Based on these results, a ground layer adaptive optics (GLAO) experimental system including a 151-element deformable mirror and the MD-SHWFS has been built at the 1m New Vacuum Solar Telescope (NVST). In this paper, the MCAO experimental system will be introduced. The preliminary experimental results of three-dimensional wavefront sensing and GLAO on the NVST of Full-shine Lake Solar Observatory are presented.

First Solar System Results of the Spitzer Space Telescope

NASA Technical Reports Server (NTRS)

VanCleve, J.; Cruikshank, D. P.; Stansberry, J. A.; Burgdorf, M. J.; Devost, D.; Emery, J. P.; Fazio, G.; Fernandez, Y. R.; Glaccum, W.; Grillmair, C.

2004-01-01

The Spitzer Space Telescope, formerly known as SIRTF, is now operational and delivers unprecedented sensitivity for the observation of Solar System targets. Spitzer's capabilities and first general results were presented at the January 2004 AAS meeting. In this poster, we focus on Spitzer's performance for moving targets, and the first Solar System results. Spitzer has three instruments, IRAC, IRS, and MIPS. IRAC (InfraRed Array Camera) provides simultaneous images at wavelengths of 3.6, 4.5, 5.8, and 8.0 microns. IRS (InfraRed Spectrograph) has 4 modules providing low-resolution (R=60-120) spectra from 5.3 to 40 microns, high-resolution (R=600) spectra from 10 to 37 m, and an autonomous target acquisition system (PeakUp) which includes small-field imaging at 15 m. MIPS (Multiband Imaging Photometer for SIRTF) does imaging photometry at 24, 70, and 160 m and low-resolution (R=15-25) spectroscopy (SED) between 55 and 96 microns. Guaranteed Time Observer (GTO) programs include the moons of the outer Solar System, Pluto, Centaurs, Kuiper Belt Objects, and comets

STS-31 Hubble Space Telescope (HST) pre-deployment procedures aboard OV-103

NASA Image and Video Library

1990-04-24

During STS-31, the Hubble Space Telescope (HST) grappled by the remote manipulator system (RMS) end effector is held in appendage deploy position above Discovery, Orbiter Vehicle (OV) 103. The solar array (SA) bistem cassette has been released from its latch fittings. The bistem spreader bars begin to unfurl the SA wing. The secondary deployment mechanism (SDM) handle is visible at the SA end. Stowed against either side of the HST System Support Module (SSM) forward shell are the high-gain antennae (HGA). Puerto Rico and the Dominican Republic are recognizable at the left of the frame.

KSC-08pd0764

NASA Image and Video Library

2008-03-20

KENNEDY SPACE CENTER, FLA. - In the Astrotech payload processing facility, General Dynamics technicians guide one of twin solar arrays toward NASA's Gamma-Ray Large Area Space Telescope, or GLAST. The telescope will launch aboard a Delta II rocket May 16 from Launch Pad 17-B on Cape Canaveral Air Force Station. A powerful space observatory, the GLAST will explore the most extreme environments in the universe, and answer questions about supermassive black hole systems, pulsars and the origin of cosmic rays. It also will study the mystery of powerful explosions known as gamma-ray bursts. Photo credit: NASA/Chris Rhodes

KSC-08pd0781

NASA Image and Video Library

2008-03-21

CAPE CANAVERAL, Fla. --- In the Astrotech payload processing facility, a General Dynamics technician prepares to test the deployment mechanism on the solar arrays on NASA's Gamma-Ray Large Area Space Telescope, or GLAST. The telescope will launch aboard a Delta II rocket May 16 from Launch Pad 17-B on Cape Canaveral Air Force Station. A powerful space observatory, the GLAST will explore the most extreme environments in the universe, and answer questions about supermassive black hole systems, pulsars and the origin of cosmic rays. It also will study the mystery of powerful explosions known as gamma-ray bursts. Photo credit: NASA/Jim Grossmann

KSC-08pd0784

NASA Image and Video Library

2008-03-21

CAPE CANAVERAL, Fla. --- In the Astrotech payload processing facility, NASA's Gamma-Ray Large Area Space Telescope, or GLAST, completes the test of the deployment mechanism on its solar arrays. The telescope will launch aboard a Delta II rocket May 16 from Launch Pad 17-B on Cape Canaveral Air Force Station. A powerful space observatory, the GLAST will explore the most extreme environments in the universe, and answer questions about supermassive black hole systems, pulsars and the origin of cosmic rays. It also will study the mystery of powerful explosions known as gamma-ray bursts. Photo credit: NASA/Jim Grossmann

KSC-08pd0762

NASA Image and Video Library

2008-03-20

KENNEDY SPACE CENTER, FLA. - In the Astrotech payload processing facility, a General Dynamics technician studies one of twin solar arrays that will be installed on NASA's Gamma-Ray Large Area Space Telescope, or GLAST. The telescope will launch aboard a Delta II rocket May 16 from Launch Pad 17-B on Cape Canaveral Air Force Station. A powerful space observatory, the GLAST will explore the most extreme environments in the universe, and answer questions about supermassive black hole systems, pulsars and the origin of cosmic rays. It also will study the mystery of powerful explosions known as gamma-ray bursts. Photo credit: NASA/Chris Rhodes

KSC-08pd0761

NASA Image and Video Library

2008-03-20

KENNEDY SPACE CENTER, FLA. - In the Astrotech payload processing facility, General Dynamics technicians prepare to install the twin solar arrays on NASA's Gamma-Ray Large Area Space Telescope, or GLAST. The telescope will launch aboard a Delta II rocket May 16 from Launch Pad 17-B on Cape Canaveral Air Force Station. A powerful space observatory, the GLAST will explore the most extreme environments in the universe, and answer questions about supermassive black hole systems, pulsars and the origin of cosmic rays. It also will study the mystery of powerful explosions known as gamma-ray bursts. Photo credit: NASA/Chris Rhodes

KSC-08pd0770

NASA Image and Video Library

2008-03-20

KENNEDY SPACE CENTER, FLA. - In the Astrotech payload processing facility, General Dynamics technicians install the second of twin solar arrays on NASA's Gamma-Ray Large Area Space Telescope, or GLAST. The telescope will launch aboard a Delta II rocket May 16 from Launch Pad 17-B on Cape Canaveral Air Force Station. A powerful space observatory, the GLAST will explore the most extreme environments in the universe, and answer questions about supermassive black hole systems, pulsars and the origin of cosmic rays. It also will study the mystery of powerful explosions known as gamma-ray bursts. Photo credit: NASA/Chris Rhodes

KSC-08pd0763

NASA Image and Video Library

2008-03-20

KENNEDY SPACE CENTER, FLA. - In the Astrotech payload processing facility, General Dynamics technicians lift one of twin solar arrays that will be installed on NASA's Gamma-Ray Large Area Space Telescope, or GLAST. The telescope will launch aboard a Delta II rocket May 16 from Launch Pad 17-B on Cape Canaveral Air Force Station. A powerful space observatory, the GLAST will explore the most extreme environments in the universe, and answer questions about supermassive black hole systems, pulsars and the origin of cosmic rays. It also will study the mystery of powerful explosions known as gamma-ray bursts. Photo credit: NASA/Chris Rhodes

KSC-08pd0782

NASA Image and Video Library

2008-03-21

CAPE CANAVERAL, Fla. --- In the Astrotech payload processing facility, a General Dynamics technician prepares to test the deployment mechanism of the solar arrays on NASA's Gamma-Ray Large Area Space Telescope, or GLAST. The telescope will launch aboard a Delta II rocket May 16 from Launch Pad 17-B on Cape Canaveral Air Force Station. A powerful space observatory, the GLAST will explore the most extreme environments in the universe, and answer questions about supermassive black hole systems, pulsars and the origin of cosmic rays. It also will study the mystery of powerful explosions known as gamma-ray bursts. Photo credit: NASA/Jim Grossmann

KSC-08pd0771

NASA Image and Video Library

2008-03-20

CAPE CANAVERAL, Fla. --- In the Astrotech payload processing facility, a General Dynamics technician finishes the installation of the second of twin solar arrays on NASA's Gamma-Ray Large Area Space Telescope, or GLAST. The telescope will launch aboard a Delta II rocket May 16 from Launch Pad 17-B on Cape Canaveral Air Force Station. A powerful space observatory, the GLAST will explore the most extreme environments in the universe, and answer questions about supermassive black hole systems, pulsars and the origin of cosmic rays. It also will study the mystery of powerful explosions known as gamma-ray bursts. Photo credit: NASA/Chris Rhodes

KSC-08pd0769

NASA Image and Video Library

2008-03-20

KENNEDY SPACE CENTER, FLA. - In the Astrotech payload processing facility, General Dynamics technicians move the second of twin solar arrays toward NASA's Gamma-Ray Large Area Space Telescope, or GLAST. The telescope will launch aboard a Delta II rocket May 16 from Launch Pad 17-B on Cape Canaveral Air Force Station. A powerful space observatory, the GLAST will explore the most extreme environments in the universe, and answer questions about supermassive black hole systems, pulsars and the origin of cosmic rays. It also will study the mystery of powerful explosions known as gamma-ray bursts. Photo credit: NASA/Chris Rhodes

KSC-08pd0766

NASA Image and Video Library

2008-03-20

KENNEDY SPACE CENTER, FLA. - In the Astrotech payload processing facility, General Dynamics technicians install one of twin solar arrays on NASA's Gamma-Ray Large Area Space Telescope, or GLAST. The telescope will launch aboard a Delta II rocket May 16 from Launch Pad 17-B on Cape Canaveral Air Force Station. A powerful space observatory, the GLAST will explore the most extreme environments in the universe, and answer questions about supermassive black hole systems, pulsars and the origin of cosmic rays. It also will study the mystery of powerful explosions known as gamma-ray bursts. Photo credit: NASA/Chris Rhodes

Kodak Mirror Assembly Tested at Marshall Space Flight Center

NASA Technical Reports Server (NTRS)

2003-01-01

The Eastman-Kodak mirror assembly is being tested for the James Webb Space Telescope (JWST) project at the X-Ray Calibration Facility at Marshall Space Flight Center (MSFC). In this photo, an MSFC employee is inspecting one of many segments of the mirror assembly for flaws. MSFC is supporting Goddard Space Flight Center (GSFC) in developing the JWST by taking numerous measurements to predict its future performance. The tests are conducted in a vacuum chamber cooled to approximate the super cold temperatures found in space. During its 27 years of operation, the facility has performed testing in support of a wide array of projects, including the Hubble Space Telescope (HST), Solar A, Chandra technology development, Chandra High Resolution Mirror Assembly and science instruments, Constellation X-Ray Mission, and Solar X-Ray Imager, currently operating on a Geostationary Operational Environment Satellite. The JWST is NASA's next generation space telescope, a successor to the Hubble Space Telescope, named in honor of NASA's second administrator, James E. Webb. It is scheduled for launch in 2010 aboard an expendable launch vehicle. It will take about 3 months for the spacecraft to reach its destination, an orbit of 940,000 miles in space.

Kodak Mirror Assembly Tested at Marshall Space Flight Center

NASA Technical Reports Server (NTRS)

2003-01-01

This photo (a frontal view) is of one of many segments of the Eastman-Kodak mirror assembly being tested for the James Webb Space Telescope (JWST) project at the X-Ray Calibration Facility at Marshall Space Flight Center (MSFC). MSFC is supporting Goddard Space Flight Center (GSFC) in developing the JWST by taking numerous measurements to predict its future performance. The tests are conducted in a vacuum chamber cooled to approximate the super cold temperatures found in space. During its 27 years of operation, the facility has performed testing in support of a wide array of projects, including the Hubble Space Telescope (HST), Solar A, Chandra technology development, Chandra High Resolution Mirror Assembly and science instruments, Constellation X-Ray Mission, and Solar X-Ray Imager, currently operating on a Geostationary Operational Environment Satellite. The JWST is NASA's next generation space telescope, a successor to the Hubble Space Telescope, named in honor of NASA's second administrator, James E. Webb. It is scheduled for launch in 2010 aboard an expendable launch vehicle. It will take about 3 months for the spacecraft to reach its destination, an orbit of 940,000 miles in space.

Kodak Mirror Assembly Tested at Marshall Space Flight Center

NASA Technical Reports Server (NTRS)

2003-01-01

This photo (a side view) is of one of many segments of the Eastman-Kodak mirror assembly being tested for the James Webb Space Telescope (JWST) project at the X-Ray Calibration Facility at Marshall Space Flight Center (MSFC). MSFC is supporting Goddard Space Flight Center (GSFC) in developing the JWST by taking numerous measurements to predict its future performance. The tests are conducted in a vacuum chamber cooled to approximate the super cold temperatures found in space. During its 27 years of operation, the facility has performed testing in support of a wide array of projects, including the Hubble Space Telescope (HST), Solar A, Chandra technology development, Chandra High Resolution Mirror Assembly and science instruments, Constellation X-Ray Mission, and Solar X-Ray Imager, currently operating on a Geostationary Operational Environment Satellite. The JWST is NASA's next generation space telescope, a successor to the Hubble Space Telescope, named in honor of NASA's second administrator, James E. Webb. It is scheduled for launch in 2010 aboard an expendable launch vehicle. It will take about 3 months for the spacecraft to reach its destination, an orbit of 940,000 miles in space.

Space Science

NASA Image and Video Library

2003-04-09

The Eastman-Kodak mirror assembly is being tested for the James Webb Space Telescope (JWST) project at the X-Ray Calibration Facility at Marshall Space Flight Center (MSFC). In this photo, an MSFC employee is inspecting one of many segments of the mirror assembly for flaws. MSFC is supporting Goddard Space Flight Center (GSFC) in developing the JWST by taking numerous measurements to predict its future performance. The tests are conducted in a vacuum chamber cooled to approximate the super cold temperatures found in space. During its 27 years of operation, the facility has performed testing in support of a wide array of projects, including the Hubble Space Telescope (HST), Solar A, Chandra technology development, Chandra High Resolution Mirror Assembly and science instruments, Constellation X-Ray Mission, and Solar X-Ray Imager, currently operating on a Geostationary Operational Environment Satellite. The JWST is NASA's next generation space telescope, a successor to the Hubble Space Telescope, named in honor of NASA's second administrator, James E. Webb. It is scheduled for launch in 2010 aboard an expendable launch vehicle. It will take about 3 months for the spacecraft to reach its destination, an orbit of 940,000 miles in space.

Space Science

NASA Image and Video Library

2003-04-09

The Eastman-Kodak mirror assembly is being tested for the James Webb Space Telescope (JWST) project at the X-Ray Calibration Facility at Marshall Space Flight Center (MSFC). In this photo, one of many segments of the mirror assembly is being set up inside the 24-ft vacuum chamber where it will undergo x-ray calibration tests. MSFC is supporting Goddard Space Flight Center (GSFC) in developing the JWST by taking numerous measurements to predict its future performance. The tests are conducted in a vacuum chamber cooled to approximate the super cold temperatures found in space. During its 27 years of operation, the facility has performed testing in support of a wide array of projects, including the Hubble Space Telescope (HST), Solar A, Chandra technology development, Chandra High Resolution Mirror Assembly and science instruments, Constellation X-Ray Mission, and Solar X-Ray Imager, currently operating on a Geostationary Operational Environment Satellite. The JWST is NASA's next generation space telescope, a successor to the Hubble Space Telescope, named in honor of NASA's second administrator, James E. Webb. It is scheduled for launch in 2010 aboard an expendable launch vehicle. It will take about 3 months for the spacecraft to reach its destination, an orbit of 940,000 miles in space.

KSC-01pp1730

NASA Image and Video Library

2001-11-27

KENNEDY SPACE CENTER, Fla. -- In the Vertical Processing Facility, members of the STS-109 crew look over the Solar Array 3 panels that will be replacing Solar Array 2 panels on the Hubble Space Telescope (HST). Trainers, at left, point to the panels while Mission Specialist Nancy Currie (second from right) and Commander Scott Altman (far right) look on. Other crew members are Pilot Duane Carey, Payload Commander John Grunsfeld and Mission Specialists James Newman, Richard Linnehan and Michael Massimino. The other goals of the mission are replacing the Power Control Unit, removing the Faint Object Camera and installing the Advanced Camera for Surveys, installing the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System, and installing New Outer Blanket Layer insulation on bays 5 through 8. Mission STS-109 is scheduled for launch Feb. 14, 2002

HST in Columbia's payload bay after repairs

NASA Image and Video Library

2002-03-09

STS109-315-016 (8 March 2002) --- With five days of service and upgrade work on the Hubble Space Telescope (HST) behind them, the STS-109 crew members on board the Space Shuttle Columbia took an overall snapshot of the giant telescope in the shuttle's cargo bay. The seven-member crew completed the last of its five ambitious space walks early on March 8, 2002, with the successful installation of an experimental cooling system for Hubble’;s Near-Infrared Camera and Multi-Object Spectrometer (NICMOS). The NICMOS has been dormant since January 1999 when its original coolant ran out. The telescope received new solar array panels, markedly different in appearance from the replaced pair, on the mission's first two space walks earlier in the week.

Astronaut Kathryn Thornton during second HST extravehicular activity

NASA Image and Video Library

1993-12-06

STS061-95-028 (6 Dec 1993) --- Astronaut Kathryn C. Thornton, on the end of the Space Shuttle Endeavour's Remote Manipulator System (RMS) arm, hovers over equipment associated with servicing chores on the Hubble Space Telescope (HST) during the second extravehicular activity (EVA) on the eleven-day mission. Astronauts Thornton and Thomas D. Akers changed out the solar array panels during this EVA.

History of Hubble Space Telescope (HST)

NASA Image and Video Library

1980-10-01

This illustration depicts the design features of the Hubble Space Telescope's (HST's) Support Systems Module (SSM). The SSM is one of the three major elements of the HST and encloses the other two elements, the Optical Telescope Assembly (OTA) and the Scientific Instruments (SI's). The purpose of the HST, the most complex and sensitive optical telescope ever made, is to study the cosmos from a low-Earth orbit. By placing the telescope in space, astronomers are able to collect data that is free of the Earth's atmosphere. The HST detects objects 25 times fainter than the dimmest objects seen from Earth and provides astronomers with an observable universe 250 times larger than visible from ground-based telescopes, perhaps as far away as 14 billion light-years. The HST views galaxies, stars, planets, comets, possibly other solar systems, and even unusual phenomena such as quasars, with 10 times the clarity of ground-based telescopes. The spacecraft is 42.5-feet (13-meters) long and weighs 25,000 pounds (11,600 kilograms). Two communication anternas, two solar array panels that collect energy for the HST, and storage bays for electronic gear are on the outside. The HST was deployed from the Space Shuttle Discovery (STS-31 mission) into Earth orbit in April 1990. The Marshall Space Flight Center had responsibility for design, development, and construction of the HST. The Perkin-Elmer Corporation, in Danbury, Connecticut, developed the optical system and guidance sensors. The Lockheed Missile and Space Company of Sunnyvale, California produced the protective outer shroud and spacecraft systems, and assembled and tested the finished telescope.

Hubble Space Telescope-The Support Systems Module

NASA Technical Reports Server (NTRS)

1980-01-01

This illustration depicts the design features of the Hubble Space Telescope's (HST's) Support Systems Module (SSM). The SSM is one of the three major elements of the HST and encloses the other two elements, the Optical Telescope Assembly (OTA) and the Scientific Instruments (SI's). The purpose of the HST, the most complex and sensitive optical telescope ever made, is to study the cosmos from a low-Earth orbit. By placing the telescope in space, astronomers are able to collect data that is free of the Earth's atmosphere. The HST detects objects 25 times fainter than the dimmest objects seen from Earth and provides astronomers with an observable universe 250 times larger than visible from ground-based telescopes, perhaps as far away as 14 billion light-years. The HST views galaxies, stars, planets, comets, possibly other solar systems, and even unusual phenomena such as quasars, with 10 times the clarity of ground-based telescopes. The spacecraft is 42.5-feet (13-meters) long and weighs 25,000 pounds (11,600 kilograms). Two communication anternas, two solar array panels that collect energy for the HST, and storage bays for electronic gear are on the outside. The HST was deployed from the Space Shuttle Discovery (STS-31 mission) into Earth orbit in April 1990. The Marshall Space Flight Center had responsibility for design, development, and construction of the HST. The Perkin-Elmer Corporation, in Danbury, Connecticut, developed the optical system and guidance sensors. The Lockheed Missile and Space Company of Sunnyvale, California produced the protective outer shroud and spacecraft systems, and assembled and tested the finished telescope.

X-ray/EUV optics for astronomy, microscopy, polarimetry, and projection lithography; Proceedings of the Meeting, San Diego, CA, July 9-13, 1990

NASA Technical Reports Server (NTRS)

Hoover, Richard B. (Editor); Walker, Arthur B. C., Jr. (Editor)

1991-01-01

Topics discussed in this issue include the fabrication of multilayer X-ray/EUV coatings; the design, characterization, and test of multilayer X-ray/EUV coatings; multilayer X-ray/EUV monochromators and imaging microscopes; X-ray/EUV telescopes; the test and calibration performance of X-ray/EUV instruments; XUV/soft X-ray projection lithography; X-ray/EUV space observatories and missions; X-ray/EUV telescopes for solar research; X-ray/EUV polarimetry; X-ray/EUV spectrographs; and X-ray/EUV filters and gratings. Papers are presented on the deposition-controlled uniformity of multilayer mirrors, interfaces in Mo/Si multilayers, the design and analysis of an aspherical multilayer imaging X-ray microscope, recent developments in the production of thin X-ray reflecting foils, and the ultraprecise scanning technology. Consideration is also given to an active sun telescope array, the fabrication and performance at 1.33 nm of a 0.24-micron-period multilayer grating, a cylindrical proportional counter for X-ray polarimetry, and the design and analysis of the reflection grating arrays for the X-Ray Multi-Mirror Mission.

New Antennas and Methods for the Low Frequency Stellar and Planetary Radio Astronomy

NASA Astrophysics Data System (ADS)

Konovalenko, A. A.; Falkovich, I. S.; Rucker, H. O.; Lecacheux, A.; Zarka, Ph.; Koliadin, V. L.; Zakharenko, V. V.; Stanislavsky, A. A.; Melnik, V. N.; Litvinenko, G. V.; Gridin, A. A.; Bubnov, I. N.; Kalinichenko, N. N.; Reznik, A. P.; Sidorchuk, M. A.; Stepkin, S. V.; Mukha, D. V.; Nikolajenko, V. S.; Karlsson, R.; Thide, B.

According to the special Program of the National Academy of Sciences of Ukraine, creation of the new giant Ukrainian radio telescope (GURT) was started a few years ago on the UTR-2 radio telescope observatory. The main goal is to reach maximum band at the lowest frequencies (10-70 MHz), effective area (step-by-step up to 100,000 sq.m), and high interference immunity for resolving many astrophysical tasks when the sensitivity is less limited by the confusion effects. These tasks include stellar radio astronomy (the Sun, solar wind, flare stars, pulsars, transients) and planetary one (Jupiter, planetary lightnings, Earth ionosphere, the Moon, exoplanets). This array should be complementary to the LOFAR, E-LOFAR systems. The first stages of the GURT (6 x 25 cross dipole active elements) and broad-band digital registration of the impulsive and sporadic events were tested in comparison with the existing largest decameter array UTR-2.

NASA Engineers Conduct Low Light Test on New Technology for NASA Webb Telescope

NASA Image and Video Library

2014-09-02

NASA engineers inspect a new piece of technology developed for the James Webb Space Telescope, the micro shutter array, with a low light test at NASA's Goddard Space Flight Center in Greenbelt, Maryland. Developed at Goddard to allow Webb's Near Infrared Spectrograph to obtain spectra of more than 100 objects in the universe simultaneously, the micro shutter array uses thousands of tiny shutters to capture spectra from selected objects of interest in space and block out light from all other sources. Credit: NASA/Goddard/Chris Gunn 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

X ray imaging microscope for cancer research

NASA Technical Reports Server (NTRS)

Hoover, Richard B.; Shealy, David L.; Brinkley, B. R.; Baker, Phillip C.; Barbee, Troy W., Jr.; Walker, Arthur B. C., Jr.

1991-01-01

The NASA technology employed during the Stanford MSFC LLNL Rocket X Ray Spectroheliograph flight established that doubly reflecting, normal incidence multilayer optics can be designed, fabricated, and used for high resolution x ray imaging of the Sun. Technology developed as part of the MSFC X Ray Microscope program, showed that high quality, high resolution multilayer x ray imaging microscopes are feasible. Using technology developed at Stanford University and at the DOE Lawrence Livermore National Laboratory (LLNL), Troy W. Barbee, Jr. has fabricated multilayer coatings with near theoretical reflectivities and perfect bandpass matching for a new rocket borne solar observatory, the Multi-Spectral Solar Telescope Array (MSSTA). Advanced Flow Polishing has provided multilayer mirror substrates with sub-angstrom (rms) smoothnesss for the astronomical x ray telescopes and x ray microscopes. The combination of these important technological advancements has paved the way for the development of a Water Window Imaging X Ray Microscope for cancer research.

Skylab

NASA Image and Video Library

1972-02-01

The Apollo Telescope Mount (ATM) was designed and developed by the Marshall Space Flight Center and served as the primary scientific instrument unit aboard Skylab (1973-1979). The ATM consisted of eight scientific instruments as well as a number of smaller experiments. In this image, the set of four large solar cell arrays, which could produce up to as much as 1.1 kilowatts of electric power, are being installed on an ATM prototype.

STS-109 MS Massimino during second EVA

NASA Image and Video Library

2002-03-05

STS109-E-5386 (5 March 2002) --- Astronaut Michael J. Massimino, mission specialist, checks a tool in the cargo bay of the Space Shuttle Columbia during the STS-109 mission's second day of extravehicular activity (EVA). Astronauts Massimino and James H. Newman worked to replace the second set of solar arrays on the Hubble Space Telescope (HST). The image was recorded with a digital still camera.

STS-109 MS Massimino during second EVA

NASA Image and Video Library

2002-03-05

STS109-E-5388 (5 March 2002) --- Astronaut Michael J. Massimino, mission specialist, checks a tool in the cargo bay of the Space Shuttle Columbia during the STS-109 mission's second day of extravehicular activity (EVA). Astronauts Massimino and James H. Newman worked to replace the second set of solar arrays on the Hubble Space Telescope (HST). The image was recorded with a digital still camera.

Solar Effects on Tensile and Optical Properties of Hubble Space Telescope Silver-Teflon(Registered Trademark) Insulation

NASA Technical Reports Server (NTRS)

deGroh, Kim, K.; Dever, Joyce A.; Snyder, Aaron; Kaminski, Sharon; McCarthy, Catherine E.; Rapoport, Alison L.; Rucker, Rochelle N.

2006-01-01

A section of the retrieved Hubble Space Telescope (HST) solar array drive arm (SADA) multilayer insulation (MLI), which experienced 8.25 years of space exposure, was analyzed for environmental durability of the top layer of silver-Teflon (DuPont) fluorinated ethylene propylene (Ag-FEP). Because the SADA MLI had solar and anti-solar facing surfaces and was exposed to the space environment for a long duration, it provided a unique opportunity to study solar effects on the environmental degradation of Ag-FEP, a commonly used spacecraft thermal control material. Data obtained included tensile properties, solar absorptance, surface morphology and chemistry. The solar facing surface was found to be extremely embrittled and contained numerous through-thickness cracks. Tensile testing indicated that the solar facing surface lost 60% of its mechanical strength and 90% of its elasticity while the anti-solar facing surface had ductility similar to pristine FEP. The solar absorptance of both the solar facing surface (0.155 plus or minus 0.032) and the anti-solar facing surface (0.208 plus or minus 0.012) were found to be greater than pristine Ag-FEP (0.074). Solar facing and anti-solar facing surfaces were microscopically textured, and locations of isolated contamination were present on the anti-solar surface resulting in increased localized texturing. Yet, the overall texture was significantly more pronounced on the solar facing surface indicating a synergistic effect of combined solar exposure and increased heating with atomic oxygen erosion. The results indicate a very strong dependence of degradation, particularly embrittlement, upon solar exposure with orbital thermal cycling having a significant effect.

TESS Solar Array Deploy

NASA Image and Video Library

2018-02-21

Inside the Payload Hazardous Servicing Facility at the NASA's Kennedy Space Center in Florida, technicians test the solar array deploy panels on the agency's Transiting Exoplanet Survey Satellite (TESS). The satellite is scheduled to launch atop a SpaceX Falcon 9 rocket from Space Launch Complex 40 at Cape Canaveral Air Force Station. TESS is the next step in NASA's search for planets outside our solar system, known as exoplanets. TESS is a NASA Astrophysics Explorer mission led and operated by MIT in Cambridge, Massachusetts, and managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Dr. George Ricker of MIT’s Kavli Institute for Astrophysics and Space Research serves as principal investigator for the mission. Additional partners include Orbital ATK, NASA’s Ames Research Center, the Harvard-Smithsonian Center for Astrophysics and the Space Telescope Science Institute. More than a dozen universities, research institutes and observatories worldwide are participants in the mission. NASA’s Launch Services Program is responsible for launch management.

Reminiscences regarding Professor R.N. Christiansen

NASA Astrophysics Data System (ADS)

Swarup, Govind

2008-11-01

In this short paper I describe my initiation into the field of radio astronomy fifty years ago, under the guidance of Professor W.N. ('Chris') Christiansen, soon after I joined the C.S.I.R.O.'s Division of Radiophysics (RP) in Sydney, Australia, in 1953 under a 2-year Colombo Plan Fellowship. During the early 1950s Christiansen had developed a remarkable 21 cm interferometric grating array of 32 east-west aligned parabolic dishes and another array of 16 dishes in a north-south direction at Potts Hill. Christiansen and Warburton used these two arrays to scan the Sun strip-wise yielding radio brightness distribution at various position angles. During a three month period I assisted them in making a 2-dimensional map of the Sun by a complex Fourier transform process. In the second year of my Fellowship, Parthasarathy and I converted the 32-antenna east-west grating array to study solar radio emission at 60cm. During this work, I noticed that the procedure adopted by Christiansen for phase adjustment of the grating array was time consuming. Based on this experience, I later developed an innovative technique at Stanford in 1959 for phase adjustment of long transmission lines and paths in space. In a bid to improve on the method used by Christiansen to make a 2-dimensional map of the Sun from strip scans, I suggested to R.N. Bracewell in 1962 a revolutionary method for direct 2-dimensional imaging without Fourier transforms. Bracewell and Riddle developed the method for making a 2-dimensional map of the Moon using strip scans obtained with the 32 element interferometer at Stanford. The method has since revolutionized medical tomography. I describe these developments here to highlight my initial work with Christiansen and to show how new ideas often are developed by necessity and have their origin in prior experience! The 32 Potts Hill solar grating array dishes were eventually donated by the C.S.I.R.0. to India and were set up by me at Kalyan near Mumbai, forming the core of the first radio astronomy group in India. This group went on to construct two of the world's largest radio telescopes, the Ooty Radio Telescope and the Giant Metrewave Radio Telescope. Chris Christiansen was not only my guru but also a mentor and a friend for more than fifty years. I fondly remember his very warm personality.

MIC-Large Scale Magnetically Inflated Cable Structures for Space Power, Propulsion, Communications and Observational Applications

NASA Astrophysics Data System (ADS)

Powell, James; Maise, George; Rather, John

2010-01-01

A new approach for the erection of rigid large scale structures in space-MIC (Magnetically Inflated Cable)-is described. MIC structures are launched as a compact payload of superconducting cables and attached tethers. After reaching orbit, the superconducting cables are energized with electrical current. The magnet force interactions between the cables cause them to expand outwards into the final large structure. Various structural shapes and applications are described. The MIC structure can be a simple flat disc with a superconducting outer ring that supports a tether network holding a solar cell array, or it can form a curved mirror surface that concentrates light and focuses it on a smaller region-for example, a high flux solar array that generates electric power, a high temperature receiver that heats H2 propellant for high Isp propulsion, and a giant primary reflector for a telescope for astronomy and Earth surveillance. Linear dipole and quadrupole MIC structures are also possible. The linear quadrupole structure can be used for magnetic shielding against cosmic radiation for astronauts, for example. MIC could use lightweight YBCO superconducting HTS (High Temperature Superconductor) cables, that can operate with liquid N2 coolant at engineering current densities of ~105 amp/cm2. A 1 kilometer length of MIC cable would weigh only 3 metric tons, including superconductor, thermal insulations, coolant circuits, and refrigerator, and fit within a 3 cubic meter compact package for launch. Four potential MIC applications are described: Solar-thermal propulsion using H2 propellant, space based solar power generation for beaming power to Earth, a large space telescope, and solar electric generation for a manned lunar base. The first 3 applications use large MIC solar concentrating mirrors, while the 4th application uses a surface based array of solar cells on a magnetically levitated MIC structure to follow the sun. MIC space based mirrors can be very large and light in weight. A 300 meter diameter MIC mirror in orbit for example, would weigh 20 metric tons and MIC structures can be easily developed and tested on Earth at small scale in existing evacuated chambers followed by larger scale tests in the atmosphere, using a vacuum tight enclosure on the small diameter superconducting cable to prevent air leakage into the evacuated thermal insulation around the superconducting cable.

Arrays vs. single telescopes

NASA Astrophysics Data System (ADS)

Johnson, H. L.

The question of the relative efficiencies of telescope arrays versus an equivalent mirror-area very large telescope is re-examined and summarized. Four separate investigations by Bowen, Johnson and Richards, Code, and Disney all came to the same conclusion: that an array of telescopes is superior, both scientifically and economically, to a single very large telescope. The costs of recently completed telescopes are compared. The costs of arrays of telescopes are shown to be significantly lower than that of a single, very large telescope, with the further advantage that because existing, proven, designs can be used, no engineering 'break-throughs' are needed.

Space Infrared Telescope Facility (SIRTF) science instruments

NASA Technical Reports Server (NTRS)

Ramos, R.; Hing, S. M.; Leidich, C. A.; Fazio, G.; Houck, J. R.

1989-01-01

Concepts of scientific instruments designed to perform infrared astronomical tasks such as imaging, photometry, and spectroscopy are discussed as part of the Space Infrared Telescope Facility (SIRTF) project under definition study at NASA/Ames Research Center. The instruments are: the multiband imaging photometer, the infrared array camera, and the infrared spectograph. SIRTF, a cryogenically cooled infrared telescope in the 1-meter range and wavelengths as short as 2.5 microns carrying multiple instruments with high sensitivity and low background performance, provides the capability to carry out basic astronomical investigations such as deep search for very distant protogalaxies, quasi-stellar objects, and missing mass; infrared emission from galaxies; star formation and the interstellar medium; and the composition and structure of the atmospheres of the outer planets in the solar sytem.

A Large Sparse Aperture Densified Pupil Hypertelescope Concept for Ground Based Detection of Extra-Solar Earth-Like Planets

NASA Technical Reports Server (NTRS)

Gezari, D.; Lyon, R.; Woodruff, R.; Labeyrie, A.; Oegerle, William (Technical Monitor)

2002-01-01

A concept is presented for a large (10 - 30 meter) sparse aperture hyper telescope to image extrasolar earth-like planets from the ground in the presence of atmospheric seeing. The telescope achieves high dynamic range very close to bright stellar sources with good image quality using pupil densification techniques. Active correction of the perturbed wavefront is simplified by using 36 small flat mirrors arranged in a parabolic steerable array structure, eliminating the need for large delat lines and operating at near-infrared (1 - 3 Micron) wavelengths with flats comparable in size to the seeing cells.

The GLObal Robotic telescopes Intelligent Array for e-science (GLORIA)

NASA Astrophysics Data System (ADS)

Castro-Tirado, A. J.; Sánchez Moreno, F. M.; Pérez del Pulgar, C.; Azócar, D.; Beskin, G.; Cabello, J.; Cedazo, R.; Cuesta, L.; Cunniffe, R.; González, E.; González-Rodríguez, A.; Gorosabel, J.; Hanlon, L.; Hudec, R.; Jakubek, M.; Janeček, P.; Jelínek, M.; Lara-Gil, O.; Linttot, C.; López-Casado, M. C.; Malaspina, M.; Mankiewicz, L.; Maureira, E.; Maza, J.; Muñoz-Martínez, V. F.; Nicastro, L.; O'Boyle, E.; Palazzi, E.; Páta, P.; Pio, M. A.; Prouza, M.; Serena, F.; Serra-Ricart, M.; Simpson, R.; Sprimont, P.; Strobl, J.; Topinka, M.; Vitek, S.; Zarnecki, A. F.

2015-05-01

GLORIA, funded under the auspices of the EU FP7 program in 2012--14, is a collaborative web--2.0 project based on a network of 18 robotic telescopes, which has become the first free-access network opened to the world for public outreach and specially for e-Science projects. On-line (solar and night) observations (experiments) as well as batch-mode (night) requests are possible. Educational material, applications (such as Personal Space) and complementary software have been also produced, besides the broadcast of several astronomical events during this period. GLORIA+ will exploit the full GLORIA potential in the years to come.

View of STS-109 MS Grunsfeld during EVA 1

NASA Image and Video Library

2002-03-04

STS109-E-5448 (4 March 2002) --- Astronaut John M. Grunsfeld, payload commander, peers into the crew cabin of the Space Shuttle Columbia during the first STS-109 extravehicular activity (EVA-1) on March 4, 2002. Grunsfeld's helmet visor displays a mirrored image of the Earth's hemisphere. Astronauts Grunsfeld and Richard M. Linnehan replaced the starboard solar array on the Hubble Space Telescope (HST) on the first of five scheduled STS-109 space walks. The lower portion of the giant telescope can be seen over Grunsfeld's left shoulder. The image was recorded with a digital still camera by a crewmate on shuttle's aft flight deck.

Minerva: A Dedicated Observatory for the Detection of Small Planets in the Solar Neighborhood

NASA Astrophysics Data System (ADS)

Hogstrom, Kristina; Johnson, J. A.; Wright, J.; McCrady, N.; Swift, J.; Muirhead, P.; Bottom, M.; Plavchan, P.; Zhao, M.; Riddle, R. L.

2013-01-01

Minerva is an array of 0.7m aperture robotic telescopes to be built atop Palomar Mountain outfitted for both photometry and high-resolution spectroscopy. It will be the first U.S. observatory dedicated to exoplanetary science capable of both precise radial velocimetry and transit studies. The multi-telescope concept will be implemented to either observe separate targets or a single target with a larger effective aperture. The flexibility of the observatory will maximize scientific potential and also provide ample opportunities for education and public outreach. The design and implementation of Minerva will be carried out by postdoctoral and student researchers at Caltech.

KSC-08pd0767

NASA Image and Video Library

2008-03-20

KENNEDY SPACE CENTER, FLA. - In the Astrotech payload processing facility, General Dynamics technicians use a socket wrench equipped with a torque meter to tighten the bolts holding one of twin solar arrays to NASA's Gamma-Ray Large Area Space Telescope, or GLAST. The telescope will launch aboard a Delta II rocket May 16 from Launch Pad 17-B on Cape Canaveral Air Force Station. A powerful space observatory, the GLAST will explore the most extreme environments in the universe, and answer questions about supermassive black hole systems, pulsars and the origin of cosmic rays. It also will study the mystery of powerful explosions known as gamma-ray bursts. Photo credit: NASA/Chris Rhodes

KSC-08pd0768

NASA Image and Video Library

2008-03-20

KENNEDY SPACE CENTER, FLA. - In the Astrotech payload processing facility, one of twin solar arrays awaits processing as General Dynamics technicians install the other of the pair on NASA's Gamma-Ray Large Area Space Telescope, or GLAST. The telescope will launch aboard a Delta II rocket May 16 from Launch Pad 17-B on Cape Canaveral Air Force Station. A powerful space observatory, the GLAST will explore the most extreme environments in the universe, and answer questions about supermassive black hole systems, pulsars and the origin of cosmic rays. It also will study the mystery of powerful explosions known as gamma-ray bursts. Photo credit: NASA/Chris Rhodes

Reliability models applicable to space telescope solar array assembly system

NASA Technical Reports Server (NTRS)

Patil, S. A.

1986-01-01

A complex system may consist of a number of subsystems with several components in series, parallel, or combination of both series and parallel. In order to predict how well the system will perform, it is necessary to know the reliabilities of the subsystems and the reliability of the whole system. The objective of the present study is to develop mathematical models of the reliability which are applicable to complex systems. The models are determined by assuming k failures out of n components in a subsystem. By taking k = 1 and k = n, these models reduce to parallel and series models; hence, the models can be specialized to parallel, series combination systems. The models are developed by assuming the failure rates of the components as functions of time and as such, can be applied to processes with or without aging effects. The reliability models are further specialized to Space Telescope Solar Arrray (STSA) System. The STSA consists of 20 identical solar panel assemblies (SPA's). The reliabilities of the SPA's are determined by the reliabilities of solar cell strings, interconnects, and diodes. The estimates of the reliability of the system for one to five years are calculated by using the reliability estimates of solar cells and interconnects given n ESA documents. Aging effects in relation to breaks in interconnects are discussed.

Kodak Mirror Assembly Tested at Marshall Space Flight Center

NASA Technical Reports Server (NTRS)

2003-01-01

The Eastman-Kodak mirror assembly is being tested for the James Webb Space Telescope (JWST) project at the X-Ray Calibration Facility at Marshall Space Flight Center (MSFC). In this photo, one of many segments of the mirror assembly is being set up inside the 24-ft vacuum chamber where it will undergo x-ray calibration tests. MSFC is supporting Goddard Space Flight Center (GSFC) in developing the JWST by taking numerous measurements to predict its future performance. The tests are conducted in a vacuum chamber cooled to approximate the super cold temperatures found in space. During its 27 years of operation, the facility has performed testing in support of a wide array of projects, including the Hubble Space Telescope (HST), Solar A, Chandra technology development, Chandra High Resolution Mirror Assembly and science instruments, Constellation X-Ray Mission, and Solar X-Ray Imager, currently operating on a Geostationary Operational Environment Satellite. The JWST is NASA's next generation space telescope, a successor to the Hubble Space Telescope, named in honor of NASA's second administrator, James E. Webb. It is scheduled for launch in 2010 aboard an expendable launch vehicle. It will take about 3 months for the spacecraft to reach its destination, an orbit of 940,000 miles in space.

LOITA: Lunar Optical/Infrared Telescope Array

NASA Technical Reports Server (NTRS)

1993-01-01

LOITA (Lunar Optical/Infrared Telescope Array) is a lunar-based interferometer composed of 18 alt-azimuth telescopes arranged in a circular geometry. This geometry results in excellent uv coverage and allows baselines up to 5 km long. The angular resolution will be 25 micro-arcsec at 500 nm and the main spectral range of the array will be 200 to 1100 nm. For infrared planet detection, the spectral range may be extended to nearly 10 mu m. The telescope mirrors have a Cassegrain configuration using a 1.75 m diameter primary mirror and a 0.24 m diameter secondary mirror. A three-stage (coarse, intermediate, and fine) optical delay system, controlled by laser metrology, is used to equalize path lengths from different telescopes to within a few wavelengths. All instruments and the fine delay system are located within the instrument room. Upon exiting the fine delay system, all beams enter the beam combiner and are then directed to the various scientific instruments and detectors. The array instrumentation will consist of CCD detectors optimized for both the visible and infrared as well as specially designed cameras and spectrographs. For direct planet detection, a beam combiner employing achromatic nulling interferometry will be used to reduce star light (by several orders of magnitude) while passing the planet light. A single telescope will be capable of autonomous operation. This telescope will be equipped with four instruments: wide field and planetary camera, faint object camera, high resolution spectrograph, and faint object spectrograph. These instruments will be housed beneath the telescope. The array pointing and control system is designed to meet the fine pointing requirement of one micro-arcsec stability and to allow precise tracking of celestial objects for up to 12 days. During the lunar night, the optics and the detectors will be passively cooled to 70-80 K temperature. To maintain a continuous communication with the earth a relay satellite placed at the L4 libration point will be used in conjunction with the Advanced Tracking and Data Relay Satellite System (ATDRSS). Electrical power of about 10 kW will be supplied by a nuclear reactor based on the SP-100 technology. LOITA will be constructed in three phases of six telescopes each. The total mass of the first operational phase is estimated at 58,820 kg. The cost of the fully operational first phase of the observatory is estimated at $8.9 billion. LOITA's primary objectives will be to detect and characterize planets around nearby stars (up to ten parsec away), study physics of collapsed stellar objects, solar/stellar surface features and the processes in nuclear regions of galaxies and quasars. An interferometric array such as LOITA will be capable of achieving resolutions three orders of magnitude greater than Hubble's design goal. LOITA will also be able to maintain higher signal to noise ratios than are currently attainable due to long observation times available on the moon.

Hubble Space Telescope Deployment-Artist's Concept

NASA Technical Reports Server (NTRS)

1980-01-01

This artist's concept depicts the Hubble Space Telescope after being released into orbit, with the high gain anternas and solar arrays deployed and the aperture doors opened. The HST is the product of a partnership between NASA, European Space Agency Contractors, and the international community of astronomers. It is named after Edwin P. Hubble, an American Astronomer who discovered the expanding nature of the universe and was the first to realize the true nature of galaxies. The purpose of the HST, the most complex and sensitive optical telescope ever made, is to study the cosmos from a low-Earth orbit. By placing the telescope in space, astronomers are able to collect data that is free of the Earth's atmosphere. The HST detects objects 25 times fainter than the dimmest objects seen from Earth and provides astronomers with an observable universe 250 times larger than visible from ground-based telescopes, perhaps as far away as 14 billion light-years. The HST views galaxies, stars, planets, comets, possibly other solar systems, and even unusual phenomena such as quasars, with 10 times the clarity of ground-based telescopes. The major elements of the HST are the Optical Telescope Assembly (OTA), the Support System Module (SSM), and the Scientific Instruments (SI). The HST is 42.5-feet (13-meters) long and weighs about 25,000 pounds (11,600 kilograms). The HST was deployed from the Space Shuttle Discovery (STS-31 mission) into Earth orbit in April 1990. The Marshall Space Flight Center had responsibility for design, development, and construction of the HST. The Perkin-Elmer Corporation, in Danbury, Connecticut, developed the optical system and guidance sensors. The Lockheed Missile and Space Company of Sunnyvale, California produced the protective outer shroud and spacecraft systems, and assembled and tested the finished telescope.

History of Hubble Space Telescope (HST)

NASA Image and Video Library

1980-01-01

This artist's concept depicts the Hubble Space Telescope after being released into orbit, with the high gain anternas and solar arrays deployed and the aperture doors opened. The HST is the product of a partnership between NASA, European Space Agency Contractors, and the international community of astronomers. It is named after Edwin P. Hubble, an American Astronomer who discovered the expanding nature of the universe and was the first to realize the true nature of galaxies. The purpose of the HST, the most complex and sensitive optical telescope ever made, is to study the cosmos from a low-Earth orbit. By placing the telescope in space, astronomers are able to collect data that is free of the Earth's atmosphere. The HST detects objects 25 times fainter than the dimmest objects seen from Earth and provides astronomers with an observable universe 250 times larger than visible from ground-based telescopes, perhaps as far away as 14 billion light-years. The HST views galaxies, stars, planets, comets, possibly other solar systems, and even unusual phenomena such as quasars, with 10 times the clarity of ground-based telescopes. The major elements of the HST are the Optical Telescope Assembly (OTA), the Support System Module (SSM), and the Scientific Instruments (SI). The HST is 42.5-feet (13-meters) long and weighs about 25,000 pounds (11,600 kilograms). The HST was deployed from the Space Shuttle Discovery (STS-31 mission) into Earth orbit in April 1990. The Marshall Space Flight Center had responsibility for design, development, and construction of the HST. The Perkin-Elmer Corporation, in Danbury, Connecticut, developed the optical system and guidance sensors. The Lockheed Missile and Space Company of Sunnyvale, California produced the protective outer shroud and spacecraft systems, and assembled and tested the finished telescope.

Mission control activity during STS-61 EVA-2

NASA Image and Video Library

1993-12-05

Harry Black, at the Integrated Communications Officer's console in the Mission Control Center (MCC), monitors the second extravehicular activity (EVA-2) of the STS-61 Hubble Space Telescope (HST) servicing mission. Others pictured, left to right, are Judy Alexander, Kathy Morrison and Linda Thomas. Note monitor scene of one of HST's original solar array panels floating in space moments after being tossed away by Astronaut Kathryn C. Thornton.

Astronauts Thomas D. Akers and Kathryn C. Thornton during WETF training

NASA Image and Video Library

1993-03-05

S93-30238 (5 Mar 1993) --- Wearing training versions of Space Shuttle Extravehicular Mobility Units (EMU), astronauts Thomas D. Akers (red stripe) and Kathryn C. Thornton use the spacious pool of the Johnson Space Center's (JSC) Weightless Environment Training Facility (WET-F) to rehearse for the Hubble Space Telescope (HST) repair mission. They are working with a full scale mockup of a solar array fixture.

STS-109 MS Linnehan and Grunsfeld in payload bay during first EVA

NASA Image and Video Library

2002-03-04

STS109-E-5253 (4 March 2002) --- Astronaut Richard M. Linnehan, mission specialist, is about to wrap up the first phase of a seven-hour space walk in the cargo bay of the Space Shuttle Columbia. Linnehan's feet are anchored to a restraint on the end of the Remote Manipulator System (RMS) robotic arm. The piece of hardware putting on a bright glow in left foreground is the furled old solar array that astronauts Linnehan and John M. Grunsfeld, payload commander, earlier removed from Hubble Space Telescope. The old array is now latched in Columbia's cargo bay for return to Earth. The two went on to install the replacement starboard array. The image was recorded with a digital still camera.

NiH2 Reliability Impact Upon Hubble Space Telescope Battery Replacement

NASA Technical Reports Server (NTRS)

Rao, Gopalakrishna M.; Hollandsworth, Roger; Armantrout, Jon; Day, John H. (Technical Monitor)

2002-01-01

The NASA Hubble Space Telescope (HST) was designed to be deployed and later serviced for maintenance and upgrades, as required, by the space shuttle fleet, with a Goodyear mission life for the batteries. HST was deployed 380 miles above the Earth, from Space Shuttle Discovery, on April 25, 1990. Four servicing missions, (SM1, SM2, SM3A, AND SM3B) have been performed. Astronauts have replaced or modified optics, solar arrays, a power control unit, and various science packages. A fifth Servicing Mission, SM4 scheduled for early 2004, is planned to replace the batteries for the first time. The HST is powered by solar array wings and nickel hydrogen (NiH2) Duracell batteries, which are grouped into two parallel battery modules of three parallel batteries each. With a design life of 7 years at launch, these batteries have surpassed 12 years in orbit, which gives HST the highest number of charge/discharge cycles of any NiH2 battery currently in low earth orbit (LEO) application. Being in a LEO orbit, HST has a 45-minute umbra period, during which spacecraft power requirements normally force the batteries into discharge, and a 60-minute sun period, which is available for battery recharge. The intent of this paper is to address the issue of NiH2 battery reliability and how battery capacity degradation can impact scheduling of a Servicing Mission to bring replacement batteries to HST, and extend mission life till deployment of Next Generation Space Telescope (NGST), planned for 2008 at the earliest.

Optical phased array configuration for an extremely large telescope.

PubMed

Meinel, Aden Baker; Meinel, Marjorie Pettit

2004-01-20

Extremely large telescopes are currently under consideration by several groups in several countries. Extrapolation of current technology up to 30 m indicates a cost of over dollars 1 billion. Innovative concepts are being explored to find significant cost reductions. We explore the concept of an Optical Phased Array (OPA) telescope. Each element of the OPA is a separate Cassegrain telescope. Collimated beams from the array are sent via an associated set of delay lines to a central beam combiner. This array of small telescope elements offers the possibility of starting with a low-cost array of a few rings of elements, adding structure and additional Cass elements until the desired diameter telescope is attained. We address the salient features of such an extremely large telescope and cost elements relative to more conventional options.

Radio Jove: Citizen Science for Jupiter Radio Astronomy

NASA Astrophysics Data System (ADS)

Higgins, C. A.; Thieman, J.; Reyes, F. J.; Typinski, D.; Flagg, R. F.; Greenman, W.; Brown, J.; Ashcraft, T.; Sky, J.; Cecconi, B.; Garcia, L. N.

2016-12-01

The Radio Jove Project (http://radiojove.gsfc.nasa.gov) has been operating as an educational activity for 18 years to introduce radio astronomy activities to students, teachers, and the general public. Participants may build a simple radio telescope kit, make scientific observations, and interact with radio observatories in real-time over the Internet. Recently some of our dedicated citizen science observers have upgraded their systems to better study radio emission from Jupiter and the Sun by adding dual-polarization spectrographs and wide-band antennas in the frequency range of 15-30 MHz. Some of these observations are being used in conjunction with professional telescopes such as the Long Wavelength Array (LWA), the Nancay Decametric Array, and the Ukrainian URAN2 Radio Telescope. In particular, there is an effort to support the Juno Mission radio waves instrument at Jupiter by using citizen science ground-based data for comparison and polarization verification. These data will be archived through a Virtual European Solar and Planetary Access (VESPA) archive (https://voparis-radiojove.obspm.fr/radiojove/welcome) for use by the amateur and professional radio science community. We overview the program and display recent observations that will be of interest to the science community.

Design of a new high-performance pointing controller for the Hubble Space Telescope

NASA Technical Reports Server (NTRS)

Johnson, C. D.

1993-01-01

A new form of high-performance, disturbance-adaptive pointing controller for the Hubble Space Telescope (HST) is proposed. This new controller is all linear (constant gains) and can maintain accurate 'pointing' of the HST in the face of persistent randomly triggered uncertain, unmeasurable 'flapping' motions of the large attached solar array panels. Similar disturbances associated with antennas and other flexible appendages can also be accommodated. The effectiveness and practicality of the proposed new controller is demonstrated by a detailed design and simulation testing of one such controller for a planar-motion, fully nonlinear model of HST. The simulation results show a high degree of disturbance isolation and pointing stability.

Hubble Space Telescope electrical power system

NASA Technical Reports Server (NTRS)

Whitt, Thomas H.; Bush, John R., Jr.

1990-01-01

The Hubble Space Telescope (HST) electrical power system (EPS) is supplying between 2000 and 2400 W of continuous power to the electrical loads. The major components of the EPS are the 5000-W back surface field reflector solar array, the six nickel-hydrogen (NiH2) 22-cell 88-Ah batteries, and the charge current controllers, which, in conjunction with the flight computer, control battery charging. The operation of the HST EPS and the results of the HST NiH2 six-battery test are discussed, and preliminary flight data are reviewed. The HST NiH2 six-battery test is a breadboard of the HST EPS on test at Marshall Space Flight Center.

Solar drum positioner mechanisms

NASA Technical Reports Server (NTRS)

Briggs, L. W.

1982-01-01

The need for additional power on spinning satellites required development of deployable solar arrays activated, as on a 3-axis vehicle, after separation from a booster or shuttle orbiter. Mechanisms were developed for telescopically extending a secondary 36.3 kg (80 lb.), 2.13 m (84 in.) diameter spinning solar drum for a distance of 2.0 m (80 in.) or more along the spin axis. After extension, the system has the capability of dynamically controlling the drum tilt angle about the spin axis to provide precision in-orbit balancing of the spacecraft. This approach was selected for the SBS, ANIK C, ANIK D, WESTAR B and PALAPA B satellites. It was successfully demonstrated during the in orbit deployment of the aft solar panels of the SBS F-3 and F-1 satellites, subsequent to the November 1980 and September 1981 launches.

STS-109 Crew Interviews - Linnehan

NASA Technical Reports Server (NTRS)

2002-01-01

STS-109 Mission Specialist 3 (MS3) Richard M. Linnehan is seen during a prelaunch interview. He answers questions about his lifelong desire to become an astronaut and his career path, which included becoming a zoo veterinarian. He gives details on the Columbia Orbiter mission, which has as its main purpose the maintenance and augmentation of the Hubble Space Telescope (HST). As MS3, his primary role in the mission pertains to EVAs (Extravehicular Activities) 1, 3, and 5. During EVA 1, Linnehan and another crewmember will replace one of two flexible solar arrays on the HST with a smaller, more efficient rigid solar array. The second solar array will be replaced on EVA 2 by other crewmembers. EVA 3 will involve the replacement of the Power Control Unit (PCU), and will require the first complete powering down of HST since its deployment. The possibility of a serious problem occurring is greatest during this portion of the mission because the original PCU was not built to be replaced. In EVA 5, Linnehan and another crewmember will install a replacement cooling system on NICMOS (Near Infrared Camera Multi-Object Spectrometer), which has not been operational. Linnehan discusses his role during the mission as well as that of his crewmates, and provides an abbreviated timeline, including possible contingencies.

Solar-A Prelaunch Mission Operation Report (MOR)

NASA Technical Reports Server (NTRS)

1991-01-01

The Solar-A mission is a Japanese-led program with the participation of the United States and the United Kingdom. The Japanese Institute of Space and Astronautical Science (ISAS) is providing the Solar-A spacecraft, two of the four science instruments, the launch vehicle and launch support, and the principal ground station with Operational Control Center. NASA is providing a science instrument, the Soft X-ray Telescope (SXT)and tracking support using the Deep Space Network (DSN) ground stations. The United Kingdom s Science and Engineering Research Council (SERC) provides the Bragg Crystal Spectrometer. The Solar-A mission will study solar flares using a cluster of instruments on a satellite in a 600 km altitude, 31 degree inclination circular orbit. The emphasis of the mission is on imaging and spectroscopy of hard and soft X-rays. The principal instruments are a pair of X-ray imaging instruments, one for the hard X-ray range and one for the soft X-ray range. The Hard X-Ray Telescope (HXT), provided by ISAS, operates in the energy range of 10-100 keV and uses an array of modulation collimators to record Fourier transform images of the non-thermal and hot plasmas that are formed during the early phases of a flare. These images are thought to be intimately associated with the sites of primary energy release. The Soft X-Ray Telescope (SXT), jointly provided by NASA and ISAS, operates in the wavelength range of 3-50 Angstroms and uses a grazing incidence mirror to form direct images of the lower temperature (but still very hot) plasmas that form as the solar atmosphere responds to the injection of energy. The SXT instrument is a joint development effort between the Lockheed Palo Alto Research Laboratory and the National Astronomical Observatory of Japan. The U.S. effort also involves Stanford University, the University of California at Berkeley and the University of Hawaii, who provide support in the areas of theory, data analysis and interpretation, and ground-based observations. The hard and soft X-ray telescopes both have an alignment sensor, operating in the visual region of the spectrum, to provide co-alignment information.

The solar optical telescope

NASA Technical Reports Server (NTRS)

1990-01-01

Objectives of the Solar Optical Telescope are to study the physics of the Sun on the scale at which many of the important physical processes occur and to attain a resolution of 73km on the Sun or 0.1 arc seconds of angular resolution. Topics discussed in this overview of the Solar Optical Telescope include: why is the Solar Optical Telescope needed; current picture of the Sun's atmosphere and convection zone; scientific problems for the Solar Optical Telescope; a description of the telescope; the facility - science management, contamination control, and accessibility to the instruments; the scientific instruments - a coordinated instrument package for unlocking the Sun's secrets; parameters of the coordinated instrument package; science operations from the Space Shuttle; and the dynamic solar atmosphere.

The solar and heliospheric imager (SoloHI) instrument for the solar orbiter mission

NASA Astrophysics Data System (ADS)

Howard, Russell A.; Vourlidas, Angelos; Korendyke, Clarence M.; Plunkett, Simon P.; Carter, Michael T.; Wang, Dennis; Rich, Nathan; McMullin, Donald R.; Lynch, Sean; Thurn, Adam; Clifford, Greg; Socker, Dennis G.; Thernisien, Arnaud F.; Chua, Damien; Linton, Mark G.; Keller, David; Janesick, James R.; Tower, John; Grygon, Mark; Hagood, Robert; Bast, William; Liewer, Paulett C.; DeJong, Eric M.; Velli, Marco M. C.; Mikic, Zoran; Bothmer, Volker; Rochus, Pierre; Halain, Jean-Philippe; Lamy, Philippe L.

2013-09-01

The SoloHI instrument for the ESA/NASA Solar Orbiter mission will track density fluctuations in the inner heliosphere, by observing visible sunlight scattered by electrons in the solar wind. Fluctuations are associated with dynamic events such as coronal mass ejections, but also with the "quiescent" solar wind. SoloHI will provide the crucial link between the low corona observations from the Solar Orbiter instruments and the in-situ measurements on Solar Orbiter and the Solar Probe Plus missions. The instrument is a visible-light telescope, based on the SECCHI/Heliospheric Imager (HI) currently flying on the STEREO mission. In this concept, a series of baffles reduce the scattered light from the solar disk and reflections from the spacecraft to levels below the scene brightness, typically by a factor of 1012. The fluctuations are imposed against a much brighter signal produced by light scattered by dust particles (the zodiacal light/F-corona). Multiple images are obtained over a period of several minutes and are summed on-board to increase the signal-to-noise ratio and to reduce the telemetry load. SoloHI is a single telescope with a 40⁰ field of view beginning at 5° from the Sun center. Through a series of Venus gravity assists, the minimum perihelia for Solar Orbiter will be reduced to about 60 Rsun (0.28 AU), and the inclination of the orbital plane will be increased to a maximum of 35° after the 7 year mission. The CMOS/APS detector is a mosaic of four 2048 x 1930 pixel arrays, each 2-side buttable with 11 μm pixels.

Hubble Space Telescope-Concept

NASA Technical Reports Server (NTRS)

1986-01-01

This is an artist's concept of the Hubble Space Telescope (HST). The HST is the product of a partnership between NASA, European Space Agency Contractors, and the international community of astronomers. It is named after Edwin P. Hubble, an American Astronomer who discovered the expanding nature of the universe and was the first to realize the true nature of galaxies. The purpose of the HST, the most complex and sensitive optical telescope ever made, is to study the cosmos from a low-Earth orbit. By placing the telescope in space, astronomers are able to collect data that is free of the Earth's atmosphere. The HST detects objects 25 times fainter than the dimmest objects seen from Earth and provides astronomers with an observable universe 250 times larger than is visible from ground-based telescopes, perhaps as far away as 14 billion light-years. The HST views galaxies, stars, planets, comets, possibly other solar systems, and even unusual phenomena such as quasars, with 10 times the clarity of ground-based telescopes. The major elements of the HST are the Optical Telescope Assembly (OTA), the Support System Module (SSM), and the Scientific Instruments (SI). The HST is approximately the size of a railroad car, with two cylinders joined together and wrapped in a silvery reflective heat shield blanket. Wing-like solar arrays extend horizontally from each side of these cylinders, and dish-shaped anternas extend above and below the body of the telescope. The HST was deployed from the Space Shuttle Discovery (STS-31 mission) into Earth orbit in April 1990. The Marshall Space Flight Center had responsibility for design, development, and construction of the HST. The Perkin-Elmer Corporation, in Danbury, Connecticut, developed the optical system and guidance sensors. The Lockheed Missile and Space Company of Sunnyvale, California produced the protective outer shroud and spacecraft systems, and assembled and tested the finished telescope.

History of Hubble Space Telescope (HST)

NASA Image and Video Library

1989-01-01

This illustration depicts a side view of the Hubble Space Telescope (HST). The HST is the product of a partnership between NASA, European Space Agency Contractors, and the international community of astronomers. It is named after Edwin P. Hubble, an American Astronomer who discovered the expanding nature of the universe and was the first to realize the true nature of galaxies. The purpose of the HST, the most complex and sensitive optical telescope ever made, is to study the cosmos from a low-Earth orbit. By placing the telescope in space, astronomers are able to collect data that is free of the Earth's atmosphere. The HST detects objects 25 times fainter than the dimmest objects seen from Earth and provides astronomers with an observable universe 250 times larger than visible from ground-based telescopes, perhaps as far away as 14 billion light-years. The HST views galaxies, stars, planets, comets, possibly other solar systems, and even unusual phenomena such as quasars, with 10 times the clarity of ground-based telescopes. The major elements of the HST are the Optical Telescope Assembly (OTA), the Support System Module (SSM), and the Scientific Instruments (SI). The HST is approximately the size of a railroad car, with two cylinders joined together and wrapped in a silvery reflective heat shield blanket. Wing-like solar arrays extend horizontally from each side of these cylinders, and dish-shaped anternas extend above and below the body of the telescope. The HST was deployed from the Space Shuttle Discovery (STS-31 mission) into Earth orbit in April 1990. The Marshall Space Flight Center had responsibility for design, development, and construction of the HST. The Perkin-Elmer Corporation, in Danbury, Connecticut, developed the optical system and guidance sensors. The Lockheed Missile and Space Company of Sunnyvale, California produced the protective outer shroud and spacecraft systems, and assembled and tested the finished telescope.

History of Hubble Space Telescope (HST)

NASA Image and Video Library

1985-04-01

This image illustrates the overall Hubble Space Telescope (HST) configuration. The HST is the product of a partnership between NASA, European Space Agency Contractors, and the international community of astronomers. It is named after Edwin P. Hubble, an American Astronomer who discovered the expanding nature of the universe and was the first to realize the true nature of galaxies. The purpose of the HST, the most complex and sensitive optical telescope ever made, is to study the cosmos from a low-Earth orbit. By placing the telescope in space, astronomers are able to collect data that is free of the Earth's atmosphere. The HST detects objects 25 times fainter than the dimmest objects seen from Earth and provides astronomers with an observable universe 250 times larger than visible from ground-based telescopes, perhaps as far away as 14 billion light-years. The HST views galaxies, stars, planets, comets, possibly other solar systems, and even unusual phenomena such as quasars, with 10 times the clarity of ground-based telescopes. The major elements of the HST are the Optical Telescope Assembly (OTA), the Support System Module (SSM), and the Scientific Instruments (SI). The HST is approximately the size of a railroad car, with two cylinders joined together and wrapped in a silvery reflective heat shield blanket. Wing-like solar arrays extend horizontally from each side of these cylinders, and dish-shaped anternas extend above and below the body of the telescope. The HST was deployed from the Space Shuttle Discovery (STS-31 mission) into Earth orbit in April 1990. The Marshall Space Flight Center had responsibility for design, development, and construction of the HST. The Perkin-Elmer Corporation, in Danbury, Connecticut, developed the optical system and guidance sensors. The Lockheed Missile and Space Company of Sunnyvale, California produced the protective outer shroud and spacecraft systems, and assembled and tested the finished telescope.

History of Hubble Space Telescope (HST)

NASA Image and Video Library

1986-01-01

This is an artist's concept of the Hubble Space Telescope (HST). The HST is the product of a partnership between NASA, European Space Agency Contractors, and the international community of astronomers. It is named after Edwin P. Hubble, an American Astronomer who discovered the expanding nature of the universe and was the first to realize the true nature of galaxies. The purpose of the HST, the most complex and sensitive optical telescope ever made, is to study the cosmos from a low-Earth orbit. By placing the telescope in space, astronomers are able to collect data that is free of the Earth's atmosphere. The HST detects objects 25 times fainter than the dimmest objects seen from Earth and provides astronomers with an observable universe 250 times larger than is visible from ground-based telescopes, perhaps as far away as 14 billion light-years. The HST views galaxies, stars, planets, comets, possibly other solar systems, and even unusual phenomena such as quasars, with 10 times the clarity of ground-based telescopes. The major elements of the HST are the Optical Telescope Assembly (OTA), the Support System Module (SSM), and the Scientific Instruments (SI). The HST is approximately the size of a railroad car, with two cylinders joined together and wrapped in a silvery reflective heat shield blanket. Wing-like solar arrays extend horizontally from each side of these cylinders, and dish-shaped anternas extend above and below the body of the telescope. The HST was deployed from the Space Shuttle Discovery (STS-31 mission) into Earth orbit in April 1990. The Marshall Space Flight Center had responsibility for design, development, and construction of the HST. The Perkin-Elmer Corporation, in Danbury, Connecticut, developed the optical system and guidance sensors. The Lockheed Missile and Space Company of Sunnyvale, California produced the protective outer shroud and spacecraft systems, and assembled and tested the finished telescope.

Feasibility study of an optically coherent telescope array in space

NASA Technical Reports Server (NTRS)

Traub, W. A.

1983-01-01

Numerical methods of image construction which can be used to produce very high angular resolution images at optical wavelengths of astronomical objects from an orbiting array of telescopes are discussed and a concept is presented for a phase-coherent optical telescope array which may be deployed by space shuttle in the 1990's. The system would start as a four-element linear array with a 12 m baseline. The initial module is a minimum redundant array with a photon-counting collecting area three times larger than space telescope and a one dimensional resolution of better than 0.01 arc seconds in the visible range. Later additions to the array would build up facility capability. The advantages of a VLBI observatory in space are considered as well as apertures for the telescopes.

Large Format Si:As IBC Array Performance for NGST and Future IR Space Telescope Applications

NASA Technical Reports Server (NTRS)

Ennico, Kimberly; Johnson, Roy; Love, Peter; Lum, Nancy; McKelvey, Mark; McCreight, Craig; McMurray, Robert, Jr.; DeVincenzi, D. (Technical Monitor)

2002-01-01

A mid-IR (5-30micrometer) instrument aboard a cryogenic space telescope can have an enormous impact in resolving key questions in astronomy and cosmology. A space platform's greatly reduced thermal backgrounds (compared to airborne or ground-based platforms), allow for more sensitive observations of dusty young galaxies at high redshifts, star formation of solar-type stars in the local universe, and formation and evolution of planetary disks and systems. The previous generation's largest, in sensitive IR detectors at these wavelengths are 256x256 pixel Si:As Impurity Band Conduction (IBC) devices built by Raytheon Infrared Operations (RIO) for the Space Infrared Telescope Facility/Infrared Array Camera (SIRTF)/(IRAC) instrument. RIO has successfully enhanced these devices, increasing the pixel count by a factor of 16 while matching or exceeding SIRTF/IRAC device performance. NASA-ARC in collaboration with RIO has tested the first high performance large format (1024x 1024) Si:As IBC arrays for low background applications, such as for the middle instrument on Next Generation Space Telescope (NGST) and future IR Explorer missions. These hybrid devices consist of radiation hard SIRTF/IRAC-type Si:As IBC material mated to a readout multiplexer that has been specially processed for operation at low cryogenic temperatures (below 10K), yielding high device sensitivity over a wavelength range of 5-28 micrometers. We present laboratory testing results from these benchmark, devices. Continued development in this technology is essential for conducting large-area surveys of the local and early universe through observation and for complementing future missions such as NGST, Terrestrial Planet Finder (TPF), and Focal Plane Instruments and Requirement Science Team (FIRST).

High resolution telescope including an array of elemental telescopes aligned along a common axis and supported on a space frame with a pivot at its geometric center

DOEpatents

Norbert, M.A.; Yale, O.

1992-04-28

A large effective-aperture, low-cost optical telescope with diffraction-limited resolution enables ground-based observation of near-earth space objects. The telescope has a non-redundant, thinned-aperture array in a center-mount, single-structure space frame. It employes speckle interferometric imaging to achieve diffraction-limited resolution. The signal-to-noise ratio problem is mitigated by moving the wavelength of operation to the near-IR, and the image is sensed by a Silicon CCD. The steerable, single-structure array presents a constant pupil. The center-mount, radar-like mount enables low-earth orbit space objects to be tracked as well as increases stiffness of the space frame. In the preferred embodiment, the array has elemental telescopes with subaperture of 2.1 m in a circle-of-nine configuration. The telescope array has an effective aperture of 12 m which provides a diffraction-limited resolution of 0.02 arc seconds. Pathlength matching of the telescope array is maintained by a electro-optical system employing laser metrology. Speckle imaging relaxes pathlength matching tolerance by one order of magnitude as compared to phased arrays. Many features of the telescope contribute to substantial reduction in costs. These include eliminating the conventional protective dome and reducing on-site construction activities. The cost of the telescope scales with the first power of the aperture rather than its third power as in conventional telescopes. 15 figs.

High resolution telescope including an array of elemental telescopes aligned along a common axis and supported on a space frame with a pivot at its geometric center

DOEpatents

Norbert, Massie A.; Yale, Oster

1992-01-01

A large effective-aperture, low-cost optical telescope with diffraction-limited resolution enables ground-based observation of near-earth space objects. The telescope has a non-redundant, thinned-aperture array in a center-mount, single-structure space frame. It employes speckle interferometric imaging to achieve diffraction-limited resolution. The signal-to-noise ratio problem is mitigated by moving the wavelength of operation to the near-IR, and the image is sensed by a Silicon CCD. The steerable, single-structure array presents a constant pupil. The center-mount, radar-like mount enables low-earth orbit space objects to be tracked as well as increases stiffness of the space frame. In the preferred embodiment, the array has elemental telescopes with subaperture of 2.1 m in a circle-of-nine configuration. The telescope array has an effective aperture of 12 m which provides a diffraction-limited resolution of 0.02 arc seconds. Pathlength matching of the telescope array is maintained by a electro-optical system employing laser metrology. Speckle imaging relaxes pathlength matching tolerance by one order of magnitude as compared to phased arrays. Many features of the telescope contribute to substantial reduction in costs. These include eliminating the conventional protective dome and reducing on-site construction activities. The cost of the telescope scales with the first power of the aperture rather than its third power as in conventional telescopes.

Space Shuttle Mission STS-61: Hubble Space Telescope servicing mission-01

NASA Technical Reports Server (NTRS)

1993-01-01

This press kit for the December 1993 flight of Endeavour on Space Shuttle Mission STS-61 includes a general release, cargo bay payloads and activities, in-cabin payloads, and STS-61 crew biographies. This flight will see the first in a series of planned visits to the orbiting Hubble Space Telescope (HST). The first HST servicing mission has three primary objectives: restoring the planned scientific capabilities, restoring reliability of HST systems and validating the HST on-orbit servicing concept. These objectives will be accomplished in a variety of tasks performed by the astronauts in Endeavour's cargo bay. The primary servicing task list is topped by the replacement of the spacecraft's solar arrays. The spherical aberration of the primary mirror will be compensated by the installation of the Wide Field/Planetary Camera-II and the Corrective Optics Space Telescope Axial Replacement. New gyroscopes will also be installed along with fuse plugs and electronic units.

STS-109 Crew Interviews: Michael J. Massimino

NASA Technical Reports Server (NTRS)

2002-01-01

STS-109 Mission Specialist Michael J. Massimino is seen during a prelaunch interview. He answers questions about his inspiration to become an astronaut, his career path, and his most memorable experiences. He gives details on the mission's goals and objectives, which focus on the refurbishing of the Hubble Space Telescope, and his role in the mission. He explains the plans for the rendezvous of the Columbia Orbiter with the Hubble Space Telescope. He provides details and timelines for each of the planned Extravehicular Activities (EVAs), which include replacing the solar arrays, changing the Power Control Unit, installing the Advanced Camera for Surveys (ACS), and installing a new Cryocooler for the Near Infrared Camera and Multi-Object Spectrometer (NICMOS). He also describes the break-out plan in place for these spacewalks. The interview ends with Massimino explaining the details of a late addition to the mission's tasks, which is to replace a reaction wheel on the Hubble Space Telescope.

SKYLAB (SL)-3 - TELEVISION

NASA Image and Video Library

1973-09-29

S73-34619 (28 July 1973) --- A composite of four frames taken from 16mm movie camera footage showing an overhead view of the Skylab space station cluster in Earth orbit. The Maurer motion picture camera scenes were being filmed during the Skylab 3 Command/Service Module's (CSM) first "fly around" inspection of the space station. Close comparison of the four frames reveals movement of the improvised parasol solar shield over the Orbital Workshop (OWS). The "flapping" of the sun shade was caused from the exhaust of the reaction control subsystem (RCS) thrusters of the Skylab 3 CSM. The one remaining solar array system wing on the OWS is in the lower left background. The solar panel in the lower left foreground is on the Apollo Telescope Mount (ATM). Photo credit: NASA

Ultrahigh resolution photographic films for X-ray/EUV/FUV astronomy

NASA Technical Reports Server (NTRS)

Hoover, Richard B.; Walker, Arthur B. C., Jr.; Deforest, Craig E.; Watts, Richard; Tarrio, Charles

1993-01-01

The quest for ultrahigh resolution full-disk images of the sun at soft X-ray/EUV/FUV wavelengths has increased the demand for photographic films with broad spectral sensitivity, high spatial resolution, and wide dynamic range. These requirements were made more stringent by the recent development of multilayer telescopes and coronagraphs capable of operating at normal incidence at soft X-ray/EUV wavelengths. Photographic films are the only detectors now available with the information storage capacity and dynamic range such as is required for recording images of the solar disk and corona simultaneously with sub arc second spatial resolution. During the Stanford/MSFC/LLNL Rocket X-Ray Spectroheliograph and Multi-Spectral Solar Telescope Array (MSSTA) programs, we utilized photographic films to obtain high resolution full-disk images of the sun at selected soft X-ray/EUV/FUV wavelengths. In order to calibrate our instrumentation for quantitative analysis of our solar data and to select the best emulsions and processing conditions for the MSSTA reflight, we recently tested several photographic films. These studies were carried out at the NIST SURF II synchrotron and the Stanford Synchrotron Radiation Laboratory. In this paper, we provide the results of those investigations.

SONTRAC: A High Efficiency Solar Neutron Telescope

NASA Astrophysics Data System (ADS)

Wunderer, C. B.; Macri, J.; McConnell, M. L.; Ryan, J. M.; Baltgalvis, J.; Holslin, D.; Polichar, A.; Jenkins, T.

1997-05-01

Solar flare neutron emission between 20 and 100 MeV comes from a portion of the energetic proton spectrum that is poorly sampled by both nuclear-line and pion- decay gamma rays. SONTRAC is a new generation solar neutron telescope/spectrometer consisting of densely packed, alternating orthogonal layers of scintillating plastic fibers. The fibers in both dimensions are viewed by image intensifiers and CCD cameras. Incident neutrons scatter off hydrogen in the plastic scintillator. The resulting ionizing proton tracks can be reconstructed in three dimensions using the two planar CCD track images. Two neutron-proton scatters provide sufficient information to reconstruct the energy and direction of the incident neutron. Photomultiplier tubes view the other sides of the fiber scintillator array. The signals from the PMTs are used to give an additional measure of the proton energies and to provide a trigger for the CCD cameras. Recent technological advances have allowed us to construct an affordable working prototype instrument that consists of all the essential technical elements mentioned above. We will present images of tracks produced by minimum ionizing muons and energetic neutrons. We will also present efficiency estimates for SONTRAC's ability to detect and measure gamma rays above 10 MeV.

Nuclear Spectroscopic Telescope Array (NuSTAR) Mission

NASA Technical Reports Server (NTRS)

Kim, Yunjin; Willis, Jason; Dodd, Suzanne; Harrison, Fiona; Forster, Karl; Craig, William; Bester, Manfred; Oberg, David

2013-01-01

The Nuclear Spectroscopic Telescope Array (NuSTAR) is a National Aeronautics and Space Administration (NASA) Small Explorer mission that carried the first focusing hard X-ray (6-79 keV) telescope into orbit. It was launched on a Pegasus rocket into a low-inclination Earth orbit on June 13, 2012, from Reagan Test Site, Kwajalein Atoll. NuSTAR will carry out a two-year primary science mission. The NuSTAR observatory is composed of the X-ray instrument and the spacecraft. The NuSTAR spacecraft is three-axis stabilized with a single articulating solar array based on Orbital Sciences Corporation's LEOStar-2 design. The NuSTAR science instrument consists of two co-aligned grazing incidence optics focusing on to two shielded solid state CdZnTe pixel detectors. The instrument was launched in a compact, stowed configuration, and after launch, a 10-meter mast was deployed to achieve a focal length of 10.15 m. The NuSTAR instrument provides sub-arcminute imaging with excellent spectral resolution over a 12-arcminute field of view. The NuSTAR observatory will be operated out of the Mission Operations Center (MOC) at UC Berkeley. Most science targets will be viewed for a week or more. The science data will be transferred from the UC Berkeley MOC to a Science Operations Center (SOC) located at the California Institute of Technology (Caltech). In this paper, we will describe the mission architecture, the technical challenges during the development phase, and the post-launch activities.

Solar Adaptive Optics.

PubMed

Rimmele, Thomas R; Marino, Jose

Adaptive optics (AO) has become an indispensable tool at ground-based solar telescopes. AO enables the ground-based observer to overcome the adverse effects of atmospheric seeing and obtain diffraction limited observations. Over the last decade adaptive optics systems have been deployed at major ground-based solar telescopes and revitalized ground-based solar astronomy. The relatively small aperture of solar telescopes and the bright source make solar AO possible for visible wavelengths where the majority of solar observations are still performed. Solar AO systems enable diffraction limited observations of the Sun for a significant fraction of the available observing time at ground-based solar telescopes, which often have a larger aperture than equivalent space based observatories, such as HINODE. New ground breaking scientific results have been achieved with solar adaptive optics and this trend continues. New large aperture telescopes are currently being deployed or are under construction. With the aid of solar AO these telescopes will obtain observations of the highly structured and dynamic solar atmosphere with unprecedented resolution. This paper reviews solar adaptive optics techniques and summarizes the recent progress in the field of solar adaptive optics. An outlook to future solar AO developments, including a discussion of Multi-Conjugate AO (MCAO) and Ground-Layer AO (GLAO) will be given. Supplementary material is available for this article at 10.12942/lrsp-2011-2.

Wave Front Sensor for Solar Concentrator Control

DTIC Science & Technology

2009-10-01

terrestrial-based and space-based. Both types of concentrator can be either imaging or nonimaging and they can be rigid or inflatable. Other...and T is the temperature of the absorber and propellant. In (5), Iin is input intensity with effects of the optical path through the concentrator acting...Hartmann in 1900 and was used for checking optical telescopes for aberrations. It was an array of holes in a plate placed in front of the mirror of

A Proposed Robotic Astronomy Mission to the Lunar South Polar Regions

NASA Technical Reports Server (NTRS)

Lowman, Paul D., Jr.

2003-01-01

This paper outlines a possible mission to emplace a robotic infrared / submillimeter wave interferometer array near the lunar south pole. This region has now been investigated by the Clementine and Lunar Prospector missions, and by Earth-based radar, and its topography and thermal environment are fairly well-known. The area would be exceptionally suitable for infrared / submillimeter astronomy because of the continually low temperatures, approaching that of liquid nitrogen (77K) in some places. A submillimeter spaceborne interferometer mission, Submillimeter Probe of the Evolution of the Cosmic Structure (SPECS) has been proposed by John Mather and others, covering the 40 - 500 micron region with 3 formation flying telescopes. The present paper proposes a lunar adaptation of the SPECS concept, LSPECS. This adaptation would involve landing 4 telescopes on the area north of Shackleton crater at zero degrees longitude. This is in nearly year round darkness but is continually radar visible from Earth. The landed payload of LSPECS would include a telerobotic rover, 4 three meter submm telescopes, a solar power array to be emplaced on the continually sunlit north rim of Shackleton crater, and an S-band antenna for data relay to Earth. Passive cooling without the use of expendable cryogenics. might be possible, trading long exposure time for instrument temperatures above that of liquid helium. The LSPECS would permit long-term study of an extremely wide range of cosmic and solar system phenomena in the southern celestial hemisphere. For complete sky coverage, a similar installation near the north pole would be required. The LSPECS site would also be suitable other types of observation, such as optical interferometry or centimeter wavelength radio astronomy. The lunar south pole is also of great interest because of its extensive ice deposits, which may represent cometary infall with pre-biotic compounds.

High resolution telescope

DOEpatents

Massie, Norbert A.; Oster, Yale

1992-01-01

A large effective-aperture, low-cost optical telescope with diffraction-limited resolution enables ground-based observation of near-earth space objects. The telescope has a non-redundant, thinned-aperture array in a center-mount, single-structure space frame. It employs speckle interferometric imaging to achieve diffraction-limited resolution. The signal-to-noise ratio problem is mitigated by moving the wavelength of operation to the near-IR, and the image is sensed by a Silicon CCD. The steerable, single-structure array presents a constant pupil. The center-mount, radar-like mount enables low-earth orbit space objects to be tracked as well as increases stiffness of the space frame. In the preferred embodiment, the array has elemental telescopes with subaperture of 2.1 m in a circle-of-nine configuration. The telescope array has an effective aperture of 12 m which provides a diffraction-limited resolution of 0.02 arc seconds. Pathlength matching of the telescope array is maintained by an electro-optical system employing laser metrology. Speckle imaging relaxes pathlength matching tolerance by one order of magnitude as compared to phased arrays. Many features of the telescope contribute to substantial reduction in costs. These include eliminating the conventional protective dome and reducing on-site construction activites. The cost of the telescope scales with the first power of the aperture rather than its third power as in conventional telescopes.

Spectro-Imaging Polarimetry of the Local Corona During Solar Eclipse

NASA Astrophysics Data System (ADS)

Qu, Z. Q.; Dun, G. T.; Chang, L.; Murray, G.; Cheng, X. M.; Zhang, X. Y.; Deng, L. H.

2017-02-01

Results are presented from spectro-imaging polarimetry of radiation from the local solar corona during the 2013 total solar eclipse in Gabon. This polarimetric observation was performed from 516.3 nm to 532.6 nm using a prototype Fiber Arrayed Solar Optical Telescope (FASOT). A polarimetric noise level on the order of 10^{-3} results from a reduced polarimetric optical switching demodulation (RPOSD) procedure for data reduction. It is revealed that the modality of fractional linear polarization profiles of the green coronal line shows a diversity, which may indicate complex mechanisms. The polarization degree can approach 3.2 % above the continuum polarization level on a scale of 1500 km, and the nonuniform spatial distribution in amplitude and polarization direction is found even within a small field of view of 7500 km. All of this implies that the coronal polarization is highly structured and complex even on a small scale.

STS-109 Onboard Photo of Extra-Vehicular Activity (EVA)

NASA Technical Reports Server (NTRS)

2002-01-01

This is an onboard photo of Astronaut John M. Grunsfield, STS-109 payload commander, participating in the third of five spacewalks to perform work on the Hubble Space Telescope (HST). On this particular walk, Grunsfield, joined by Astronaut Richard M. Lirnehan, turned off the telescope in order to replace its power control unit (PCU), the heart of the HST's power system. The telescope was captured and secured on a work stand in Columbia's payload bay using Columbia's robotic arm, where crew members completed system upgrades to the HST. Included in those upgrades were: replacement of the solar array panels; replacement of the power control unit (PCU); replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS); and installation of the experimental cooling system for the Hubble's Near-Infrared Camera and Multi-object Spectrometer (NICMOS), which had been dormant since January 1999 when its original coolant ran out. The Marshall Space Flight Center had the responsibility for the design, development, and construction of the HST, which is the most complex and sensitive optical telescope ever made, to study the cosmos from a low-Earth orbit. The HST detects objects 25 times fainter than the dimmest objects seen from Earth and provides astronomers with an observable universe 250 times larger than is visible from ground-based telescopes, perhaps as far away as 14 billion light-years. The HST views galaxies, stars, planets, comets, possibly other solar systems, and even unusual phenomena such as quasars, with 10 times the clarity of ground-based telescopes. Launched March 1, 2002 the STS-109 HST servicing mission lasted 10 days, 22 hours, and 11 minutes. It was the 108th flight overall in NASA's Space Shuttle Program.

A synthetic aperture radio telescope for ICME observations as a potential payload of SPORT

NASA Astrophysics Data System (ADS)

Zhang, C.; Sun, W.; Liu, H.; Xiong, M.; Liu, Y. D.; Wu, J.

2013-12-01

We introduce a potential payload for the Solar Polar ORbit Telescope (SPORT), a space weather mission proposed by the National Space Science Center, Chinese Academy of Sciences. This is a synthetic aperture radio imager designed to detect radio emissions from interplanetary coronal mass ejections (ICMEs), which is expected to be an important instrument to monitor the propagation and evolution of ICMEs. The radio telescope applies a synthetic aperture interferometric technique to measure the brightness temperature of ICMEs. Theoretical calculations of the brightness temperature utilizing statistical properties of ICMEs and the background solar wind indicate that ICMEs within 0.35 AU from the Sun are detectable by a radio telescope at a frequency <= 150 MHz with a sensitivity of <=1 K. The telescope employs a time shared double rotation scan (also called a clock scan), where two coplanar antennas revolve around a fixed axis at different radius and speed, to fulfill sampling of the brightness temperature. An array of 4+4 elements with opposite scanning directions are developed for the radio telescope to achieve the required sensitivity (<=1K) within the imaging refreshing time (~30 minutes). This scan scheme is appropriate for a three-axis stabilized spacecraft platform while keeping a good sampling pattern. We also discuss how we select the operating frequency, which involves a trade-off between the engineering feasibility and the scientific goal. Our preliminary results indicate that the central frequency of 150 MHz with a bandwidth of 20 MHz, which requires arm lengths of the two groups of 14m and 16m, respectively, gives an angular resolution of 2°, a field of view of ×25° around the Sun, and a time resolution of 30 minutes.

Space Shuttle Projects

NASA Image and Video Library

2002-03-06

This is an onboard photo of Astronaut John M. Grunsfield, STS-109 payload commander, participating in the third of five spacewalks to perform work on the Hubble Space Telescope (HST). On this particular walk, Grunsfield, joined by Astronaut Richard M. Lirnehan, turned off the telescope in order to replace its power control unit (PCU), the heart of the HST's power system. The telescope was captured and secured on a work stand in Columbia's payload bay using Columbia's robotic arm, where crew members completed system upgrades to the HST. Included in those upgrades were: replacement of the solar array panels; replacement of the power control unit (PCU); replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS); and installation of the experimental cooling system for the Hubble's Near-Infrared Camera and Multi-object Spectrometer (NICMOS), which had been dormant since January 1999 when its original coolant ran out. The Marshall Space Flight Center had the responsibility for the design, development, and construction of the HST, which is the most complex and sensitive optical telescope ever made, to study the cosmos from a low-Earth orbit. The HST detects objects 25 times fainter than the dimmest objects seen from Earth and provides astronomers with an observable universe 250 times larger than is visible from ground-based telescopes, perhaps as far away as 14 billion light-years. The HST views galaxies, stars, planets, comets, possibly other solar systems, and even unusual phenomena such as quasars, with 10 times the clarity of ground-based telescopes. Launched March 1, 2002 the STS-109 HST servicing mission lasted 10 days, 22 hours, and 11 minutes. It was the 108th flight overall in NASA's Space Shuttle Program.

VizieR Online Data Catalog: HeI 5876 & 10830Å EWs of solar-type stars (Andretta+, 2017)

NASA Astrophysics Data System (ADS)

Andretta, V.; Giampapa, M. S.; Covino, E.; Reiners, A.; Beeck, B.

2017-11-01

A total of 134 FEROS spectra (R=48000) of our targets (including telluric standards) were acquired on the night of UT 2011 December 6-7; spectral coverage from 3500 to 9200Å. The Fiber Extended-range Optical Spectrograph (FEROS) was mounted at the 2.2m Max-Planck Gesellschaft/European Southern Observatory (MPG/ESO) telescope at La Silla (Chile). The HeIλ10830 spectroscopic observations were carried out on the same night as the FEROS D3 observations, using the CRyogenic high-resolution InfraRed Echelle Spectrograph (CRIRES), mounted at Unit Telescope 1 (Antu) of the VLT array at Cerro Paranal. The details of the observations is given in table 1. (3 data files).

Nickel-cadium batteries for Apollo telescope mount

NASA Technical Reports Server (NTRS)

Kirsch, W. W.; Shikoh, A. E.

1974-01-01

The operational testing and evaluation program is presented which was conducted on 20-ampere-hour nickel-cadmium (Ni-Cd) batteries for use on the Apollo telescope mount (ATM). The test program was initiated in 1967 to determine if the batteries could meet ATM mission requirements and to determine operating characteristics and methods. The ATM system power and charging power for the Ni-Cd secondary batteries is provided by a solar array during the 58-minute daylight portion of the orbit; during the 36-minute night portion of the orbit, the Ni-Cd secondary batteries will supply ATM system power. The test results reflect battery operating characteristics and parameters relative to simulated ATM orbital test conditions. Maximum voltage, charge requirements, capacity, temperature, and cyclic characteristics are presented.

Space Shuttle Projects

NASA Image and Video Library

2001-08-01

This is the insignia of the STS-109 Space Shuttle mission. Carrying a crew of seven, the Space Shuttle Orbiter Columbia was launched with goals of maintenance and upgrades to the Hubble Space Telescope (HST). The Marshall Space Flight Center had the responsibility for the design, development, and construction of the HST, which is the most complex and sensitive optical telescope ever made, to study the cosmos from a low-Earth orbit. The HST detects objects 25 times fainter than the dimmest objects seen from Earth and provides astronomers with an observable universe 250 times larger than is visible from ground-based telescopes, perhaps as far away as 14 billion light-years. The HST views galaxies, stars, planets, comets, possibly other solar systems, and even unusual phenomena such as quasars, with 10 times the clarity of ground-based telescopes. During the STS-109 mission, the telescope was captured and secured on a work stand in Columbia's payload bay using Columbia's robotic arm where four members of the crew performed five spacewalks completing system upgrades to the HST. Included in those upgrades were: The replacement of the solar array panels; replacement of the power control unit (PCU); replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS); and installation of the experimental cooling system for the Hubble's Near-Infrared Camera and Multi-object Spectrometer (NICMOS), which had been dormant since January 1999 when it original coolant ran out. Lasting 10 days, 22 hours, and 11 minutes, the STS-109 mission was the 27th flight of the Orbiter Columbia and the 108th flight overall in NASA's Space Shuttle Program.

Space Shuttle Projects

NASA Image and Video Library

2002-03-03

This is a photo of the Hubble Space Telescope (HST),in its origianl configuration, berthed in the cargo bay of the Space Shuttle Columbia during the STS-109 mission silhouetted against the airglow of the Earth's horizon. The telescope was captured and secured on a work stand in Columbia's payload bay using Columbia's robotic arm, where 4 of the 7-member crew performed 5 spacewalks completing system upgrades to the HST. Included in those upgrades were: replacement of the solar array panels; replacement of the power control unit (PCU); replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS); and installation of the experimental cooling system for the Hubble's Near-Infrared Camera and Multi-object Spectrometer (NICMOS), which had been dormant since January 1999 when its original coolant ran out. The Marshall Space Flight Center had the responsibility for the design, development, and construction of the the HST, which is the most complex and sensitive optical telescope ever made, to study the cosmos from a low-Earth orbit. The HST detects objects 25 times fainter than the dimmest objects seen from Earth and provides astronomers with an observable universe 250 times larger than is visible from ground-based telescopes, perhaps as far away as 14 billion light-years. The HST views galaxies, stars, planets, comets, possibly other solar systems, and even unusual phenomena such as quasars, with 10 times the clarity of ground-based telescopes. Launched March 1, 2002 the STS-109 HST servicing mission lasted 10 days, 22 hours, and 11 minutes. It was the 108th flight overall in NASA's Space Shuttle Program.

KSC-99pp0351

NASA Image and Video Library

1999-03-26

In the Vertical Processing Facility, TRW technicians look at the point of attachment on the Chandra X-ray Observatory, at left, for the solar panel array (behind them). They are getting ready to attach and deploy the solar panel. Formerly called the Advanced X-ray Astrophysics Facility, Chandra comprises three major elements: the spacecraft, the science instrument module (SIM), and the world's most powerful X-ray telescope. Chandra will allow scientists from around the world to see previously invisible black holes and high-temperature gas clouds, giving the observatory the potential to rewrite the books on the structure and evolution of our universe. Chandra is scheduled for launch July 9 aboard Space Shuttle Columbia, on mission STS-93

Monte Carlo studies of medium-size telescope designs for the Cherenkov Telescope Array

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

Wood, M. D.; Jogler, T.; Dumm, J.

In this paper, we present studies for optimizing the next generation of ground-based imaging atmospheric Cherenkov telescopes (IACTs). Results focus on mid-sized telescopes (MSTs) for CTA, detecting very high energy gamma rays in the energy range from a few hundred GeV to a few tens of TeV. We describe a novel, flexible detector Monte Carlo package, FAST (FAst Simulation for imaging air cherenkov Telescopes), that we use to simulate different array and telescope designs. The simulation is somewhat simplified to allow for efficient exploration over a large telescope design parameter space. We investigate a wide range of telescope performance parametersmore » including optical resolution, camera pixel size, and light collection area. In order to ensure a comparison of the arrays at their maximum sensitivity, we analyze the simulations with the most sensitive techniques used in the field, such as maximum likelihood template reconstruction and boosted decision trees for background rejection. Choosing telescope design parameters representative of the proposed Davies–Cotton (DC) and Schwarzchild–Couder (SC) MST designs, we compare the performance of the arrays by examining the gamma-ray angular resolution and differential point-source sensitivity. We further investigate the array performance under a wide range of conditions, determining the impact of the number of telescopes, telescope separation, night sky background, and geomagnetic field. We find a 30–40% improvement in the gamma-ray angular resolution at all energies when comparing arrays with an equal number of SC and DC telescopes, significantly enhancing point-source sensitivity in the MST energy range. Finally, we attribute the increase in point-source sensitivity to the improved optical point-spread function and smaller pixel size of the SC telescope design.« less

Monte Carlo studies of medium-size telescope designs for the Cherenkov Telescope Array

DOE PAGES

Wood, M. D.; Jogler, T.; Dumm, J.; ...

2015-06-07

In this paper, we present studies for optimizing the next generation of ground-based imaging atmospheric Cherenkov telescopes (IACTs). Results focus on mid-sized telescopes (MSTs) for CTA, detecting very high energy gamma rays in the energy range from a few hundred GeV to a few tens of TeV. We describe a novel, flexible detector Monte Carlo package, FAST (FAst Simulation for imaging air cherenkov Telescopes), that we use to simulate different array and telescope designs. The simulation is somewhat simplified to allow for efficient exploration over a large telescope design parameter space. We investigate a wide range of telescope performance parametersmore » including optical resolution, camera pixel size, and light collection area. In order to ensure a comparison of the arrays at their maximum sensitivity, we analyze the simulations with the most sensitive techniques used in the field, such as maximum likelihood template reconstruction and boosted decision trees for background rejection. Choosing telescope design parameters representative of the proposed Davies–Cotton (DC) and Schwarzchild–Couder (SC) MST designs, we compare the performance of the arrays by examining the gamma-ray angular resolution and differential point-source sensitivity. We further investigate the array performance under a wide range of conditions, determining the impact of the number of telescopes, telescope separation, night sky background, and geomagnetic field. We find a 30–40% improvement in the gamma-ray angular resolution at all energies when comparing arrays with an equal number of SC and DC telescopes, significantly enhancing point-source sensitivity in the MST energy range. Finally, we attribute the increase in point-source sensitivity to the improved optical point-spread function and smaller pixel size of the SC telescope design.« less

STS-109 Mission Highlights Resource Tape

NASA Astrophysics Data System (ADS)

2002-05-01

This video, Part 2 of 4, shows the activities of the STS-109 crew (Scott Altman, Commander; Duane Carey, Pilot; John Grunsfeld, Payload Commander; Nancy Currie, James Newman, Richard Linnehan, Michael Massimino, Mission Specialists) during flight days 4 and 5. The activities from other flights days can be seen on 'STS-109 Mission Highlights Resource Tape' Part 1 of 4 (internal ID 2002139471), 'STS-109 Mission Highlights Resource Tape' Part 3 of 4 (internal ID 2002139476), and 'STS-109 Mission Highlights Resource Tape' Part 4 of 4 (internal ID 2002137577). The primary activities during these days were EVAs (extravehicular activities) to replace two solar arrays on the HST (Hubble Space Telescope). Footage from flight day 4 records an EVA by Grunsfeld and Linnehan, including their exit from Columbia's payload bay airlock, their stowing of the old HST starboard rigid array on the rigid array carrier in Columbia's payload bay, their attachment of the new array on HST, the installation of a new starboard diode box, and the unfolding of the new array. The pistol grip space tool used to fasten the old array in its new location is shown in use. The video also includes several shots of the HST with Earth in the background. On flight day 5 Newman and Massimino conduct an EVA to change the port side array and diode box on HST. This EVA is very similar to the one on flight day 4, and is covered similarly in the video. A hand operated ratchet is shown in use. In addition to a repeat of the previous tasks, the astronauts change HST's reaction wheel assembly, and because they are ahead of schedule, install installation and lubricate an instrument door on the telescope. The Earth views include a view of Egypt and Israel, with the Nile River, Red Sea, and Mediterranean Sea.

Optical aperture synthesis with electronically connected telescopes

PubMed Central

Dravins, Dainis; Lagadec, Tiphaine; Nuñez, Paul D.

2015-01-01

Highest resolution imaging in astronomy is achieved by interferometry, connecting telescopes over increasingly longer distances and at successively shorter wavelengths. Here, we present the first diffraction-limited images in visual light, produced by an array of independent optical telescopes, connected electronically only, with no optical links between them. With an array of small telescopes, second-order optical coherence of the sources is measured through intensity interferometry over 180 baselines between pairs of telescopes, and two-dimensional images reconstructed. The technique aims at diffraction-limited optical aperture synthesis over kilometre-long baselines to reach resolutions showing details on stellar surfaces and perhaps even the silhouettes of transiting exoplanets. Intensity interferometry circumvents problems of atmospheric turbulence that constrain ordinary interferometry. Since the electronic signal can be copied, many baselines can be built up between dispersed telescopes, and over long distances. Using arrays of air Cherenkov telescopes, this should enable the optical equivalent of interferometric arrays currently operating at radio wavelengths. PMID:25880705

MuSICa at GRIS: a prototype image slicer for EST at GREGOR

NASA Astrophysics Data System (ADS)

Calcines, A.; Collados, M.; López, R. L.

2013-05-01

This communication presents a prototype image slicer for the 4-m European Solar Telescope (EST) designed for the spectrograph of the 1.5-m GREGOR solar telescope (GRIS). The design of this integral field unit has been called MuSICa (Multi-Slit Image slicer based on collimator-Camera). It is a telecentric system developed specifically for the integral field, high resolution spectrograph of EST and presents multi-slit capability, reorganizing a bidimensional field of view of 80 arcsec^{2} into 8 slits, each one of them with 200 arcsec length × 0.05 arcsec width. It minimizes the number of optical components needed to fulfil this multi-slit capability, three arrays of mirrors: slicer, collimator and camera mirror arrays (the first one flat and the other two spherical). The symmetry of the layout makes it possible to overlap the pupil images associated to each part of the sliced entrance field of view. A mask with only one circular aperture is placed at the pupil position. This symmetric characteristic offers some advantages: facilitates the manufacturing process, the alignment and reduces the costs. In addition, it is compatible with two modes of operation: spectroscopic and spectro-polarimetric, offering a great versatility. The optical quality of the system is diffraction-limited. The prototype will improve the performances of GRIS at GREGOR and is part of the feasibility study of the integral field unit for the spectrographs of EST. Although MuSICa has been designed as a solar image slicer, its concept can also be applied to night-time astronomical instruments (Collados et al. 2010, Proc. SPIE, Vol. 7733, 77330H; Collados et al. 2012, AN, 333, 901; Calcines et al. 2010, Proc. SPIE, Vol. 7735, 77351X)

Experiments on solar photovoltaic power generation using concentrator and liquid cooling

NASA Technical Reports Server (NTRS)

Beam, B. H.; Hansen, C. F.

1975-01-01

Calculations and experimental data are presented leading to the development of a practical, economical solar photovoltaic power supply. The concept involves concentration of sunlight up to about 100 times normal solar intensity in a solar tracking collector and directing this to an array of solar cells. The cells are immersed in water circulated from a thermal reservoir which limits cell temperature rise to about 20 C above ambient during the day and which cools to ambient temperature during the night. Experiments were conducted on solar cells using a Fresnel lens for magnification, a telescope equatorial mount with clock drive, and tap water circulated through the solar cell holder cavity. Test results show that cells operate satisfactorily under these conditions. Power outputs achieved experimentally with cell optimized for 25 suns were linear with concentration to about 15 suns. Cells optimized for 100 suns were not available, but a corresponding linear relation of power output with concentration is anticipated. Test results have been used in a design analysis of the cost of systems utilizing this technique.

Battery Resistance Analysis of ISS Power System

NASA Technical Reports Server (NTRS)

Newstadt, Gregory E.

2004-01-01

The computer package, SPACE (Systems Power Analysis for Capability Evaluation) was created by the members of LT-9D to perform power analysis and modeling of the electrical power system on the International Space Station (ISS). Written in FORTRAN, SPACE comprises thousands of lines of code and has been used profficiently in analyzing missions to the ISS. LT-9D has also used its expertise recently to investigate the batteries onboard the Hubble telescope. During the summer of 2004, I worked with the members of LT-9D, under the care of Dave McKissock. Solar energy will power the ISS through eight solar arrays when the ISS is completed, although only two arrays are currently connected. During the majority of the periods of sunlight, the solar arrays provide enough energy for the ISS. However, rechargeable Nickel-Hydrogen batteries are used during eclipse periods or at other times when the solar arrays cannot be used (at docking for example, when the arrays are turned so that they will not be damaged by the Shuttle). Thirty-eight battery cells are connected in series, which make up an ORU (Orbital Replacement Unit). An ISS "battery" is composed of two ORUs. a great deal of time into finding the best way to represent them in SPACE. During my internship, I investigated the resistance of the ISS batteries. SPACE constructs plots of battery charge and discharge voltages vs. time using a constant current. To accommodate for a time-varying current, the voltages are adjusted using the formula, DeltaV = DeltaI * Cell Resistance. To enhance our model of the battery resistance, my research concentrated on several topics: investigating the resistance of a qualification unit battery (using data gathered by LORAL), comparing the resistance of the qualification unit to SPACE, looking at the internal resistance and wiring resistance, and examining the impact of possible recommended changes to SPACE. The ISS batteries have been found to be very difficult to model, and LT-9D has dedicated

Concept-Development of a Structure Supported Membrane for Deployable Space Applications - From Nature to Manufacture and Testing

NASA Technical Reports Server (NTRS)

Zander, Martin; Belvin, W. K.

2012-01-01

Current space applications of membrane structures include large area solar power arrays, solar sails, antennas, and numerous other large aperture devices like the solar shades of the new James Webb Space Telescope. These expandable structural systems, deployed in-orbit to achieve the desired geometry, are used to collect, reflect and/or transmit electromagnetic radiation. This work, a feasibility study supporting a diploma thesis, describes the systematic process for developing a biologically inspired concept for a structure supported (integrated) membrane, that features a rip stop principle, makes self-deployment possible and is part of an ultra-light weight space application. Novel manufacturing of membrane prototypes and test results are presented for the rip-stop concepts. Test data showed that the new membrane concept has a higher tear resistance than neat film of equivalent mass.

Development of software for the MSFC solar vector magnetograph

NASA Technical Reports Server (NTRS)

Kineke, Jack

1996-01-01

The Marshall Space Flight Center Solar Vector Magnetograph is a special purpose telescope used to measure the vector magnetic field in active areas on the surface of the sun. This instrument measures the linear and circular polarization intensities (the Stokes vectors Q, U and V) produced by the Zeeman effect on a specific spectral line due to the solar magnetic field from which the longitudinal and transverse components of the magnetic field may be determined. Beginning in 1990 as a Summer Faculty Fellow in project JOVE and continuing under NASA Grant NAG8-1042, the author has been developing computer software to perform these computations, first using a DEC MicroVAX system equipped with a high speed array processor, and more recently using a DEC AXP/OSF system. This summer's work is a continuation of this development.

Facilities for High Resolution Imaging of the Sun

NASA Astrophysics Data System (ADS)

von der Lühe, Oskar

2018-04-01

The Sun is the only star where physical processes can be observed at their intrinsic spatial scales. Even though the Sun in a mere 150 million km from Earth, it is difficult to resolve fundamental processes in the solar atmosphere, because they occur at scales of the order of the kilometer. They can be observed only with telescopes which have apertures of several meters. The current state-of-the-art are solar telescopes with apertures of 1.5 m which resolve 50 km on the solar surface, soon to be superseded by telescopes with 4 m apertures with 20 km resolution. The US American 4 m DSI Solar Telescope is currently constructed on Maui, Hawaii, and is expected to have first light in 2020. The European solar community collaborates intensively to pursue the 4 m European Solar Telescope with a construction start in the Canaries early in the next decade. Solar telescopes with slightly smaller are also in the planning by the Russian, Indian and Chinese communities. In order to achieve a resolution which approaches the diffraction limit, all modern solar telescopes use adaptive optics which compensates virtually any scene on the solar disk. Multi-conjugate adaptive optics designed to compensate fields of the order on one minute of arc have been demonstrated and will become a facility feature of the new telescopes. The requirements for high precision spectro-polarimetry – about one part in 104 – makes continuous monitoring of (MC)AO performance and post-processing image reconstruction methods a necessity.

MEMS Microshutter Arrays for James Webb Space Telescope

NASA Technical Reports Server (NTRS)

Li, Mary J.; Beamesderfer, Michael; Babu, Sachi; Bajikar, Sateesh; Ewin, Audrey; Franz, Dave; Hess, Larry; Hu, Ron; Jhabvala, Murzy; Kelly, Dan;

STS-109 Crew Interviews: James H. Newman

NASA Technical Reports Server (NTRS)

2002-01-01

STS-109 Mission Specialist James H. Newman is seen during a prelaunch interview. He answers questions about his inspiration to become an astronaut, his career path, and his most memorable experiences. He gives details on the mission's goals and objectives, which focus on the refurbishing of the Hubble Space Telescope, and his role in the mission. He provides a brief background on the Hubble Space Telescope, and explains the plans for the rendezvous of the Columbia Orbiter with the Hubble Space Telescope. He provides details and timelines for each of the planned Extravehicular Activities (EVAs), which include replacing the solar arrays, changing the Power Control Unit, installing the Advanced Camera for Surveys (ACS), and installing a new Cryocooler for the Near Infrared Camera and Multi-Object Spectrometer (NICMOS). He gives further explanation of each of these pieces of equipment. He also describes the break-out plan in place for these spacewalks. The interview ends with Newman explaining the details of a late addition to the mission's tasks, which is to replace a reaction wheel on the Hubble Space Telescope.

Space Shuttle Projects

NASA Image and Video Library

2002-03-08

After five days of service and upgrade work on the Hubble Space Telescope (HST), the STS-109 crew photographed the giant telescope in the shuttle's cargo bay. The telescope was captured and secured on a work stand in Columbia's payload bay using Columbia's robotic arm, where 4 of the 7-member crew performed 5 space walks completing system upgrades to the HST. Included in those upgrades were: The replacement of the solar array panels; replacement of the power control unit (PCU); replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS); and installation of the experimental cooling system for the Hubble's Near-Infrared Camera and Multi-object Spectrometer (NICMOS), which had been dormant since January 1999 when its original coolant ran out. The Marshall Space Flight Center had the responsibility for the design, development, and construction of the the HST, which is the most complex and sensitive optical telescope ever made, to study the cosmos from a low-Earth orbit. Launched March 1, 2002, the STS-109 HST servicing mission lasted 10 days, 22 hours, and 11 minutes. It was the 108th flight overall in NASA's Space Shuttle Program.

n/a

NASA Image and Video Library

2002-03-09

After five days of service and upgrade work on the Hubble Space Telescope (HST), the STS-109 crew photographed the giant telescope returning to its normal routine. The telescope was captured and secured on a work stand in Columbia's payload bay using Columbia's robotic arm, where 4 of the 7-member crew performed 5 space walks completing system upgrades to the HST. Included in those upgrades were: The replacement of the solar array panels; replacement of the power control unit (PCU); replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS); and installation of the experimental cooling system for the Hubble's Near- Infrared Camera and Multi-object Spectrometer (NICMOS), which had been dormant since January 1999 when its original coolant ran out. The Marshall Space Flight Center had the responsibility for the design, development, and construction of the the HST, which is the most complex and sensitive optical telescope ever made, to study the cosmos from a low-Earth orbit. Launched March 1, 2002, the STS-109 HST servicing mission lasted 10 days, 22 hours, and 11 minutes. It was the 108th flight overall in NASA's Space Shuttle Program.

Cassiopeia A supernova

NASA Image and Video Library

2017-12-08

NASA's Fermi Closes on Source of Cosmic Rays New images from NASA's Fermi Gamma-ray Space Telescope show where supernova remnants emit radiation a billion times more energetic than visible light. The images bring astronomers a step closer to understanding the source of some of the universe's most energetic particles -- cosmic rays. This composite shows the Cassiopeia A supernova remnant across the spectrum: Gamma rays (magenta) from NASA's Fermi Gamma-ray Space Telescope; X-rays (blue, green) from NASA's Chandra X-ray Observatory; visible light (yellow) from the Hubble Space Telescope; infrared (red) from NASA's Spitzer Space Telescope; and radio (orange) from the Very Large Array near Socorro, N.M. Credit: NASA/DOE/Fermi LAT Collaboration, CXC/SAO/JPL-Caltech/Steward/O. Krause et al., and NRAO/AUI For more information: www.nasa.gov/mission_pages/GLAST/news/cosmic-rays-source.... NASA Goddard Space Flight Center is home to the nation's largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe. Follow us on Twitter Join us on Facebook

Telescope Array Results on UHE Cosmic Rays and the Plan

NASA Astrophysics Data System (ADS)

Sagawa, Hiroyuki

The Telescope Array (TA) is the largest experiment in the Northern Hemisphere studying the origin and nature of ultra-high-energy cosmic rays. The TA detector consists of a surface array of 507 scintillation counters covering approximately 700 km2, and 38 fluorescence telescopes located at three sites looking over the surface array. Here, recent TA results using the first five years of data and our ongoing and near-future plans are presented.

Utilization of a Curved Local Surface Array in a 3.5m Wide field of View Telescope

DTIC Science & Technology

2013-09-01

ABSTRACT Wide field of view optical telescopes have a range of uses for both astronomical and space -surveillance purposes. In designing these...Agency (DARPA) 3.5-m Space Surveillance Telescope (SST)), the choice was made to curve the array to best satisfy the stressing telescope performance...dramatically improves the nation’s space surveillance capabilities. This paper will discuss the implementation of the curved focal-surface array, the

Information and Communications Technology (ICT) Infrastructure for the ASTRI SST-2M telescope prototype for the Cherenkov Telescope Array

NASA Astrophysics Data System (ADS)

Gianotti, F.; Tacchini, A.; Leto, G.; Martinetti, E.; Bruno, P.; Bellassai, G.; Conforti, V.; Gallozzi, S.; Mastropietro, M.; Tanci, C.; Malaguti, G.; Trifoglio, M.

2016-08-01

The Cherenkov Telescope Array (CTA) represents the next generation of ground-based observatories for very high energy gamma-ray astronomy. The CTA will consist of two arrays at two different sites, one in the northern and one in the southern hemisphere. The current CTA design foresees, in the southern site, the installation of many tens of imaging atmospheric Cherenkov telescopes of three different classes, namely large, medium and small, so defined in relation to their mirror area; the northern hemisphere array would consist of few tens of the two larger telescope types. The Italian National Institute for Astrophysics (INAF) is developing the Cherenkov Small Size Telescope ASTRI SST- 2M end-to-end prototype telescope within the framework of the International Cherenkov Telescope Array (CTA) project. The ASTRI prototype has been installed at the INAF observing station located in Serra La Nave on Mt. Etna, Italy. Furthermore a mini-array, composed of nine of ASTRI telescopes, has been proposed to be installed at the Southern CTA site. Among the several different infrastructures belonging the ASTRI project, the Information and Communication Technology (ICT) equipment is dedicated to operations of computing and data storage, as well as the control of the entire telescope, and it is designed to achieve the maximum efficiency for all performance requirements. Thus a complete and stand-alone computer centre has been designed and implemented. The goal is to obtain optimal ICT equipment, with an adequate level of redundancy, that might be scaled up for the ASTRI mini-array, taking into account the necessary control, monitor and alarm system requirements. In this contribution we present the ICT equipment currently installed at the Serra La Nave observing station where the ASTRI SST-2M prototype will be operated. The computer centre and the control room are described with particular emphasis on the Local Area Network scheme, the computing and data storage system, and the telescope control and monitoring.

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

NASA Technical Reports Server (NTRS)

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

2014-01-01

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

An Array of Optical Receivers for Deep-Space Communications

NASA Technical Reports Server (NTRS)

Vilnrotter, Chi-Wung; Srinivasan, Meera; Andrews, Kenneth

2007-01-01

An array of small optical receivers is proposed as an alternative to a single large optical receiver for high-data-rate communications in NASA s Deep Space Network (DSN). Because the telescope for a single receiver capable of satisfying DSN requirements must be greater than 10 m in diameter, the design, building, and testing of the telescope would be very difficult and expensive. The proposed array would utilize commercially available telescopes of 1-m or smaller diameter and, therefore, could be developed and verified with considerably less difficulty and expense. The essential difference between a single-aperture optical-communications receiver and an optical-array receiver is that a single-aperture receiver focuses all of the light energy it collects onto the surface of an optical detector, whereas an array receiver focuses portions of the total collected energy onto separate detectors, optically detects each fractional energy component, then combines the electrical signal from the array of detector outputs to form the observable, or "decision statistic," used to decode the transmitted data. A conceptual block diagram identifying the key components of the optical-array receiver suitable for deep-space telemetry reception is shown in the figure. The most conspicuous feature of the receiver is the large number of small- to medium-size telescopes, with individual apertures and number of telescopes selected to make up the desired total collecting area. This array of telescopes is envisioned to be fully computer- controlled via the user interface and prediction-driven to achieve rough pointing and tracking of the desired spacecraft. Fine-pointing and tracking functions then take over to keep each telescope pointed toward the source, despite imperfect pointing predictions, telescope-drive errors, and vibration caused by wind.

Balloon platform for extended-life astronomy research

NASA Technical Reports Server (NTRS)

Ostwald, L. T.

1974-01-01

A configuration has been developed for a long-life balloon platform to carry pointing telescopes weighing as much as 80 pounds (36 kg) to point at selected celestial targets. A platform of this configuration weighs about 375 pounds (170 kg) gross and can be suspended from a high altitude super pressure balloon for a lifetime of several months. The balloon platform contains a solar array and storage batteries for electrical power, up and down link communications equipment, and navigational and attitude control systems for orienting the scientific instrument. A biaxial controller maintains the telescope attitude in response to look-angle data stored in an on-board computer memory which is updated periodically by ground command. Gimbal angles are computed by using location data derived by an on-board navigational receiver.

Telescope Array Low energy Extension: TALE

NASA Astrophysics Data System (ADS)

Ogio, Shoichi

TALE, the Telescope Array Low Energy extension was designed to lower the energy threshold to about 1016.5 eV. TALE has a surface detector (SD) array made up of 103 scintillation counters (40 with 400 m spacing, 36 with 600 m spacing and 27 with 1.2 km spacing) and a Fluorescence Detector (FD) station consisting of ten FD telescopes working with the Telescope Array Middle Drum FD station, which is made up of 14 telescopes. TALE-FD full operation started in 2013 and the SD array was partially-completed with 16 SDs and continues the operation from 2014. We will describe the history and the current status of the detectors and will make a brief report about the FD and the hybrid analysis results. TALE detector will be completed as a hybrid air shower detector in 2018. We will report the technical details of the detectors, the schedule and the expected performances.

Optomechanical and thermal design of the Multi-Application Solar Telescope for USO

NASA Astrophysics Data System (ADS)

Denis, Stefan; Coucke, Pierre; Gabriel, Eric; Delrez, Christophe; Venkatakrishnan, Parameshwaran

2008-07-01

The Multi-Application Solar Telescope (MAST) is a 50 cm diameter class telescope to be installed on the Udaipur Solar Observatory's Island on the Lake Fatehsagar in Udaipur, India. It is dedicated to solar observation. The telescope is designed, manufactured, assembled and installed on-site by the belgian company AMOS SA for the Udaipur Solar Observatory (USO), an academic division of the Physical Research Laboratory (PRL) in India. Despite its limited size, the telescope is expected to be competitive with respect to worldwide large and costly projects thanks to its versatility regarding science goals and also thanks to its demanding optomechanical and thermal specification. This paper describes the optomechanical and thermal design of this telescope and presents solutions adopted by AMOS to meet the specific requirements. The optical configuration of the telescope is based on an afocal off-axis gregorian combination integrated on an Alt.-Az. mechanical mount, with a suite of flat folding mirrors to provide the required stationary collimated beam.

The SOLAR-C Mission: Plan B Payload Concept

NASA Astrophysics Data System (ADS)

Shimizu, T.; Sakao, T.; Katsukawa, Y.; Group, J. S. W.

2012-08-01

The telescope concepts for the SOLAR-C Plan B mission as of the time of the Hinode-3 meeting were briefly presented for having comments from the international solar physics community. The telescope candidates are 1) near IR-visible-UV telescope with 1.5m aperture and enhanced spectro-polarimetric capability, 2) UV/EUV high throughput spectrometer, and 3) next generation X-ray telescope.

DEATH-STAR: Silicon and photovoltaic fission fragment detector arrays for light-ion induced fission correlation studies

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

Koglin, J. D.; Burke, J. T.; Fisher, S. E.

Here, the Direct Excitation Angular Tracking pHotovoltaic-Silicon Telescope ARray (DEATH-STAR) combines a series of 12 silicon detectors in a ΔE–E configuration for charged particle identification with a large-area array of 56 photovoltaic (solar) cells for detection of fission fragments. The combination of many scattering angles and fission fragment detectors allows for an angular-resolved tool to study reaction cross sections using the surrogate method, anisotropic fission distributions, and angular momentum transfers through stripping, transfer, inelastic scattering, and other direct nuclear reactions. The unique photovoltaic detectors efficiently detect fission fragments while being insensitive to light ions and have a timing resolution ofmore » 15.63±0.37 ns. Alpha particles are detected with a resolution of 35.5 keV 1σ at 7.9 MeV. Measured fission fragment angular distributions are also presented.« less

DEATH-STAR: Silicon and Photovoltaic Fission Fragment Detector Arrays for Light-Ion Induced Fission Correlation Studies

NASA Astrophysics Data System (ADS)

Koglin, J. D.; Burke, J. T.; Fisher, S. E.; Jovanovic, I.

2017-05-01

The Direct Excitation Angular Tracking pHotovoltaic-Silicon Telescope ARray (DEATH-STAR) combines a series of 12 silicon detectors in a ΔE - E configuration for charged particle identification with a large-area array of 56 photovoltaic (solar) cells for detection of fission fragments. The combination of many scattering angles and fission fragment detectors allows for an angular-resolved tool to study reaction cross sections using the surrogate method, anisotropic fission distributions, and angular momentum transfers through stripping, transfer, inelastic scattering, and other direct nuclear reactions. The unique photovoltaic detectors efficiently detect fission fragments while being insensitive to light ions and have a timing resolution of 15.63±0.37 ns. Alpha particles are detected with a resolution of 35.5 keV 1σ at 7.9 MeV. Measured fission fragment angular distributions are also presented.

DEATH-STAR: Silicon and photovoltaic fission fragment detector arrays for light-ion induced fission correlation studies

DOE PAGES

Koglin, J. D.; Burke, J. T.; Fisher, S. E.; ...

2017-02-20

Here, the Direct Excitation Angular Tracking pHotovoltaic-Silicon Telescope ARray (DEATH-STAR) combines a series of 12 silicon detectors in a ΔE–E configuration for charged particle identification with a large-area array of 56 photovoltaic (solar) cells for detection of fission fragments. The combination of many scattering angles and fission fragment detectors allows for an angular-resolved tool to study reaction cross sections using the surrogate method, anisotropic fission distributions, and angular momentum transfers through stripping, transfer, inelastic scattering, and other direct nuclear reactions. The unique photovoltaic detectors efficiently detect fission fragments while being insensitive to light ions and have a timing resolution ofmore » 15.63±0.37 ns. Alpha particles are detected with a resolution of 35.5 keV 1σ at 7.9 MeV. Measured fission fragment angular distributions are also presented.« less

Operating performance of the gamma-ray Cherenkov telescope: An end-to-end Schwarzschild-Couder telescope prototype for the Cherenkov Telescope Array

NASA Astrophysics Data System (ADS)

Dournaux, J. L.; De Franco, A.; Laporte, P.; White, R.; Greenshaw, T.; Sol, H.; Abchiche, A.; Allan, D.; Amans, J. P.; Armstrong, T. P.; Balzer, A.; Berge, D.; Boisson, C.; Bousquet, J. J.; Brown, A. M.; Bryan, M.; Buchholtz, G.; Chadwick, P. M.; Costantini, H.; Cotter, G.; Daniel, M.; De Frondat, F.; Dumas, D.; Ernenwein, J. P.; Fasola, G.; Funk, S.; Gaudemard, J.; Graham, J. A.; Gironnet, J.; Hervet, O.; Hidaka, N.; Hinton, J. A.; Huet, J. M.; Jégouzo, I.; Jogler, T.; Kawashima, T.; Kraus, M.; Lapington, J. S.; Lefaucheur, J.; Markoff, S.; Melse, T.; Morhrmann, L.; Molnyeux, P.; Nolan, S. J.; Okumura, A.; Parsons, R. D.; Ross, D.; Rowell, G.; Sato, Y.; Sayède, F.; Schmoll, J.; Schoorlemmer, H.; Servillat, M.; Stamatescu, V.; Stephan, M.; Stuik, R.; Sykes, J.; Tajima, H.; Thornhill, J.; Tibaldo, L.; Trichard, C.; Vink, J.; Watson, J.; Yamane, N.; Zech, A.; Zink, A.; CTA Consortium

2017-02-01

The Cherenkov Telescope Array (CTA) consortium aims to build the next-generation ground-based very-high-energy gamma-ray observatory. The array will feature different sizes of telescopes allowing it to cover a wide gamma-ray energy band from about 20 GeV to above 100 TeV. The highest energies, above 5 TeV, will be covered by a large number of Small-Sized Telescopes (SSTs) with a field-of-view of around 9°. The Gamma-ray Cherenkov Telescope (GCT), based on Schwarzschild-Couder dual-mirror optics, is one of the three proposed SST designs. The GCT is described in this contribution and the first images of Cherenkov showers obtained using the telescope and its camera are presented. These were obtained in November 2015 in Meudon,

The Gamma-ray Cherenkov Telescope, an end-to end Schwarzschild-Couder telescope prototype proposed for the Cherenkov Telescope Array

NASA Astrophysics Data System (ADS)

Dournaux, J. L.; Abchiche, A.; Allan, D.; Amans, J. P.; Armstrong, T. P.; Balzer, A.; Berge, D.; Boisson, C.; Bousquet, J.-J.; Brown, A. M.; Bryan, M.; Buchholtz, G.; Chadwick, P. M.; Costantini, H.; Cotter, G.; Dangeon, L.; Daniel, M. K.; De Franco, A.; De Frondat, F.; Dumas, D.; Ernenwein, J. P.; Fasola, G.; Funk, S.; Gironnet, J.; Graham, J. A.; Greenshaw, T.; Hameau, B.; Hervet, O.; Hidaka, N.; Hinton, J. A.; Huet, J. M.; Jégouzo, I.; Jogler, T.; Kawashima, T.; Kraush, M.; Lapington, J. S.; Laporte, P.; Lefaucheur, J.; Markoff, S.; Melse, T.; Mohrmann, L.; Molyneux, P.; Nolan, S. J.; Okumura, A.; Osborne, J. P.; Parsons, R. D.; Rosen, S.; Ross, D.; Rowell, G.; Rulten, C. B.; Sato, Y.; Sayède, F.; Schmoll, J.; Schoorlemmer, H.; Servillat, M.; Sol, H.; Stamatescu, V.; Stephan, M.; Stuik, R.; Sykes, J.; Tajima, H.; Thornhill, J.; Tibaldo, L.; Trichard, C.; Vink, J.; Watson, J. J.; White, R.; Yamane, N.; Zech, A.; Zink, A.

2016-08-01

The GCT (Gamma-ray Cherenkov Telescope) is a dual-mirror prototype of Small-Sized-Telescopes proposed for the Cherenkov Telescope Array (CTA) and made by an Australian-Dutch-French-German-Indian-Japanese-UK-US consortium. The integration of this end-to-end telescope was achieved in 2015. On-site tests and measurements of the first Cherenkov images on the night sky began on November 2015. This contribution describes the telescope and plans for the pre-production and a large scale production within CTA.

Hard X-ray Detectability of Small-Scale Coronal Heating Events

NASA Astrophysics Data System (ADS)

Marsh, A.; Glesener, L.; Klimchuk, J. A.; Bradshaw, S. J.; Smith, D. M.; Hannah, I. G.

2016-12-01

The nanoflare heating theory predicts the ubiquitous presence of hot ( >5 MK) plasma in the solar corona, but evidence for this high-temperature component has been scarce. Current hard x-ray instruments such as RHESSI lack the sensitivity to see the trace amounts of this plasma that are predicted by theoretical models. New hard X-ray instruments that use focusing optics, such as FOXSI (the Focusing Optics X-ray Solar Imager) and NuSTAR (the Nuclear Spectroscopic Telescope Array) can extend the visible parameter space of nanoflare "storms" that create hot plasma. We compare active-region data from FOXSI and NuSTAR with a series of EBTEL hydrodynamic simulations, and constrain nanoflare properties to give good agreement with observations.

Hard X-ray Detectability of Small-Scale Coronal Heating Events

NASA Astrophysics Data System (ADS)

Marsh, Andrew; Glesener, Lindsay; Klimchuk, James A.; Bradshaw, Stephen; Smith, David; Hannah, Iain

2016-05-01

The nanoflare heating theory predicts the ubiquitous presence of hot (~>5 MK) plasma in the solar corona, but evidence for this high-temperature component has been scarce. Current hard x-ray instruments such as RHESSI lack the sensitivity to see the trace amounts of this plasma that are predicted by theoretical models. New hard X-ray instruments that use focusing optics, such as FOXSI (the Focusing Optics X-ray Solar Imager) and NuSTAR (the Nuclear Spectroscopic Telescope Array) can extend the visible parameter space of nanoflare “storms” that create hot plasma. We compare active-region data from FOXSI and NuSTAR with a series of EBTEL hydrodynamic simulations, and constrain nanoflare properties to give good agreement with observations.

Sun sensor boresight alignment testing for the Halogen Occultation Experiment

NASA Technical Reports Server (NTRS)

Moore, A. S.; Laney, V. S.; Mauldin, L. E., III

1987-01-01

The boresight alignment testing for the sun sensor assembly on the Halogen Occultation Experiment (HALOE) is described. The sun sensor assembly consists of three sensors that provide feedback signals for controlling dual axes gimbals. Two energy balancing silicon detectors are operated as wideband sensors in the azimuth and elevation axes. The third sensor is a silicon photodiode array operated as a narrow-band sensor in the elevation axis. These sensors are mounted on a common Invar structure which is mounted to the HALOE telescope. A blackbody was used as the stimulating source to perform the initial boresight alignment and this was checked with a heliostat solar look and a direct solar look. These tests are explained with a comparison between each source used.

Space Shuttle Projects

NASA Image and Video Library

2002-03-01

Carrying a crew of seven, the Space Shuttle Orbiter Columbia soared through some pre-dawn clouds into the sky as it began its 27th flight, STS-109. Launched March 1, 2002, the goal of the mission was the maintenance and upgrade of the Hubble Space Telescope (HST). The Marshall Space Flight Center had the responsibility for the design, development, and construction of the HST, which is the most complex and sensitive optical telescope ever made, to study the cosmos from a low-Earth orbit. The HST detects objects 25 times fainter than the dimmest objects seen from Earth and provides astronomers with an observable universe 250 times larger than is visible from ground-based telescopes, perhaps as far away as 14 billion light-years. The HST views galaxies, stars, planets, comets, possibly other solar systems, and even unusual phenomena such as quasars, with 10 times the clarity of ground-based telescopes. During the STS-109 mission, the telescope was captured and secured on a work stand in Columbia's payload bay using Columbia's robotic arm. Here four members of the crew performed five spacewalks completing system upgrades to the HST. Included in those upgrades were: replacement of the solar array panels; replacement of the power control unit (PCU); replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS); and installation of the experimental cooling system for the Hubble's Near-Infrared Camera and Multi-object Spectrometer (NICMOS), which had been dormant since January 1999 when it original coolant ran out. Lasting 10 days, 22 hours, and 11 minutes, the STS-109 mission was the 108th flight overall in NASA's Space Shuttle Program.

Bringing Perfect Vision to the Daniel K. Inouye Solar Telescope

NASA Astrophysics Data System (ADS)

Matijevich, Russ; Johansson, Erik; Johnson, Luke; Cavaco, Jeff; National Solar Observatory

2016-01-01

The world's largest ground-based solar telescope is one step closer to operation with the acceptance of the deformable mirror engineered by AOA Xinetics, a Northrop Grumman Corporation company. The Daniel K. Inouye Solar Telescope (DKIST), currently under construction in Haleakala, Hawaii, will offer unprecedented high-resolution images of the sun using the latest adaptive optics technology to provide its distortion-free imaging.Led by the National Solar Observatory (NSO) and the Association of Universities for Research in Astronomy (AURA), the Inouye Solar Telescope will help scientists better understand how magnetic fields affect the physical properties of the Sun, what roles they play in our solar system and how they affect Earth.Ground-based telescopes, whether observing the sun or the night sky must contend with atmospheric turbulence that acts as a flexible lens, constantly reshaping observed images. This turbulence makes research on solar activity difficult and drives the need for the latest adaptive optics technology.To provide DKIST with the distortion-free imaging it requires, AOA Xinetics designed a deformable mirror with 1,600 actuators, four times the normal actuator density. This deformable mirror (DM) is instrumental in removing all of the atmospheric blurriness that would otherwise limit the telescope's performance. The mirror also has an internal thermal management system to handle the intense solar energy coming from DKIST's telescope. This poster provides the history behind this incredible success story.

Multilayer and grazing incidence X-ray/EUV optics; Proceedings of the Meeting, San Diego, CA, July 22-24, 1991

NASA Technical Reports Server (NTRS)

Hoover, Richard B. (Editor)

1992-01-01

The present conference discusses the Advanced X-ray Astrophysics Facility (AXAF) calibration by means of synchrotron radiation and its X-ray reflectivity, X-ray scattering measurements from thin-foil X-ray mirrors, lobster-eye X-ray optics using microchannel plates, space-based interferometry at EUV and soft X-ray wavelengths, a water-window imaging X-ray telescope, a graded d-spacing multilayer telescope for high energy X-ray astronomy, photographic films for the multispectral solar telescope array, a soft X-ray ion chamber, and the development of hard X-ray optics. Also discussed are X-ray spectroscopy with multilayered optics, a slit aperture for monitoring X-ray experiments, an objective double-crystal spectrometer, a Ly-alpha coronagraph/polarimeter, tungsten/boron nitride multilayers for XUV optical applications, the evaluation of reflectors for soft X-ray optics, the manufacture of elastically bent crystals and multilayer mirrors, and selective photodevices for the VUV.

Precise Determination of the Orientation of the Solar Image

NASA Astrophysics Data System (ADS)

Győri, L.

2010-12-01

Accurate heliographic coordinates of objects on the Sun have to be known in several fields of solar physics. One of the factors that affect the accuracy of the measurements of the heliographic coordinates is the accuracy of the orientation of a solar image. In this paper the well-known drift method for determining the orientation of the solar image is applied to data taken with a solar telescope equipped with a CCD camera. The factors that influence the accuracy of the method are systematically discussed, and the necessary corrections are determined. These factors are as follows: the trajectory of the center of the solar disk on the CCD with the telescope drive turned off, the astronomical refraction, the change of the declination of the Sun, and the optical distortion of the telescope. The method can be used on any solar telescope that is equipped with a CCD camera and is capable of taking solar full-disk images. As an example to illustrate the method and its application, the orientation of solar images taken with the Gyula heliograph is determined. As a byproduct, a new method to determine the optical distortion of a solar telescope is proposed.

A Mission to Study Water Throughout The Universe

NASA Astrophysics Data System (ADS)

Goldsmith, Paul F.

2015-08-01

A variety of recent observations have revealed important new information about the distribution of water in the universe, and dramatically expanded its role as a tracer of key stages in the formation of stars and planetary systems. These include water in planetary atmospheres, an asteroid (Ceres), and comets in the solar system by Herschel and Rosetta. Observations of the protoplanetary disk TWHydra have revealed emission from water. Herschel observations of water in a collapsing cloud core (in combination with other molecular lines) have been able to determine the velocity field. Water has also been extensively studied in diffuse interstellar clouds and has been showed to be a valuable tracer of physical conditions and chemistry in these regions. A space mission dedicated to observations of water throughout the universe is appropriate and timely. A critical unifying characteristic of all of the above is that the line widths are very narrow and so high spectral resolution is essential. This means that for the water lines throughout the submillimeter spectral region, heterodyne systems are required. For such systems, the thermal emission from the telescope is negligible so a cold telescope is not necessary. Technology advances allow focal plane array systems with 16 and possibly 64 pixels to frequencies as high as 5 GHz. There have been significant reduction in system noise, but increasing the collecting area is the main way to significantly improve the sensitivity. We have been developing a concept for a space mission that will employ a 8m-9m diameter telescope with a suite of heterodyne focal plane array receivers and broadband digital spectrometers. The collecting area will be factor >5 greater than that of Herschel, and the angular resolution improved by a factor ~2.5. The telescope can be folded to allow a relatively low cost Falcon 9 launch. The surface accuracy should allow observations up to ~2 THz frequency, including a variety of ortho- and para-H2O lines. Other key tracers of the interstellar medium such as C+ and OI can also be covered, making this an enormously exciting concept for future studies of the solar system, the Milky Way, and nearby galaxies.

Some design considerations for a satellite-borne magnetograph

NASA Technical Reports Server (NTRS)

Rust, D. M.

1985-01-01

The design criteria for a compact magnetograph that can monitor solar magnetic fields from a free-flying satellite for 5 to 10 years are reviewed. The signal-to-noise ratio that can be obtained with a 10-cm f/10 refractor operated with a Fabry-Perot filter and a solid-state detector array is derived. The telescope measures the longitudinal component of the magnetic field for the entire solar disk in a few minutes at a 20-G threshold and at 3-arcsec resolution. The Fabry-Perot filter has a lithium niobate etalon, which can be tuned electrically and operated at a fixed tilt angle in such a manner that it cancels the solar rotational Doppler shifts in the transmitted spectrum. Principles of operation of various types of polarization modulators are presented, and it is concluded that photoelastic modulators and liquid-crystal devices hold the most promise for use in a satellite-borne magnetograph,

The Lyman-alpha Solar Telescope for the ASO-S

NASA Astrophysics Data System (ADS)

Li, Hui

2015-08-01

The Lyman-alpha Solar Telescope (LST) is one of the payloads for the proposed Space-Borne Advanced Solar Observatory (ASO-S). LST consists of a Solar Disk Imager (SDI) with a field-of-view (FOV) of 1.2 Rsun, a Solar Corona Imager (SCI) with an FOV of 1.1 - 2.5 Rsun, and a full-disk White-light Solar Telescope (WST) with an FOV of 1.2 Rsun, which also serves as the guiding telescope. The SCI is designed to work at the Lyman-alpha waveband and white-light, while the SDI will work at the Lyman-alpha waveband only. The WST works both in visible (for guide) and ultraviolet (for science) white-light. The LST will observe the Sun from disk-center up to 2.5 solar radii for both solar flares and coronal mass ejections. In this presentation, I will give an introduction to LST, including scientific objectives, science requirement, instrument design and current status.

The Lyman-α Solar Telescope (LST) for the ASO-S mission

NASA Astrophysics Data System (ADS)

Li, Hui

The Lyman-α (Lyα) Solar Telescope (LST) is one of the payloads for the proposed Space-Borne Advanced Solar Observatory (ASO-S). LST consists of a Solar Disk Imager (SDI) with a field-of-view (FOV) of 1.2 R⊙ (R⊙ = solar radius), a Solar Corona Imager (SCI) with an FOV of 1.1 - 2.5 R⊙, and a full-disk White-light Solar Telescope (WST) with the same FOV as the SDI, which also serves as the guiding telescope. The SCI is designed to work in the Lyα (121.6 nm) waveband and white-light (for polarization brightness observation), while the SDI will work in the Lyα waveband only. The WST works in both visible (for guide) and ultraviolet (for science) broadband. The LST will observe the Sun from disk-center up to 2.5 R⊙ for both solar flares and coronal mass ejections with high tempo-spatial resolution

High-power, ultralow-mass solar arrays: FY-77 solar arrays technology readiness assessment report, volume 2

NASA Technical Reports Server (NTRS)

Costogue, E. N.; Young, L. E.; Brandhorst, H. W., Jr.

1978-01-01

Development efforts are reported in detail for: (1) a lightweight solar array system for solar electric propulsion; (2) a high efficiency thin silicon solar cell; (3) conceptual design of 200 W/kg solar arrays; (4) fluorocarbon encapsulation for silicon solar cell array; and (5) technology assessment of concentrator solar arrays.

KSC-99pp0355

NASA Image and Video Library

1999-03-26

In the Vertical Processing Facility, TRW technicians check the point of attachment of the solar panel array at right. Formerly called the Advanced X-ray Astrophysics Facility, Chandra comprises three major elements: the spacecraft, the science instrument module (SIM), and the world's most powerful X-ray telescope. Chandra will allow scientists from around the world to see previously invisible black holes and high-temperature gas clouds, giving the observatory the potential to rewrite the books on the structure and evolution of our universe. Chandra is scheduled for launch July 9 aboard Space Shuttle Columbia, on mission STS-93

Development of the quality control system of the readout electronics for the large size telescope of the Cherenkov Telescope Array observatory

NASA Astrophysics Data System (ADS)

Konno, Y.; Kubo, H.; Masuda, S.; Paoletti, R.; Poulios, S.; Rugliancich, A.; Saito, T.

2016-07-01

The Cherenkov Telescope Array (CTA) is the next generation VHE γ-ray observatory which will improve the currently available sensitivity by a factor of 10 in the range 100 GeV to 10 TeV. The array consists of different types of telescopes, called large size telescope (LST), medium size telescope (MST) and small size telescope (SST). A LST prototype is currently being built and will be installed at the Observatorio Roque de los Muchachos, island of La Palma, Canary islands, Spain. The readout system for the LST prototype has been designed and around 300 readout boards will be produced in the coming months. In this note we describe an automated quality control system able to measure basic performance parameters and quickly identify faulty boards.

The ASTRI mini-array software system (MASS) implementation: a proposal for the Cherenkov Telescope Array

NASA Astrophysics Data System (ADS)

Tanci, Claudio; Tosti, Gino; Conforti, Vito; Schwarz, Joseph; Antolini, Elisa; Antonelli, L. A.; Bulgarelli, Andrea; Bigongiari, Ciro; Bruno, Pietro; Canestrari, Rodolfo; Capalbi, Milvia; Cascone, Enrico; Catalano, Osvaldo; Di Paola, Andrea; Di Pierro, Federico; Fioretti, Valentina; Gallozzi, Stefano; Gardiol, Daniele; Gianotti, Fulvio; Giro, Enrico; Grillo, Alessandro; La Palombara, Nicola; Leto, Giuseppe; Lombardi, Saverio; Maccarone, Maria C.; Pareschi, Giovanni; Russo, Federico; Sangiorgi, Pierluca; Scuderi, Salvo; Stringhetti, Luca; Testa, Vincenzo; Trifoglio, Massimo; Vercellone, Stefano; Zoli, Andrea

2016-08-01

The ASTRI mini-array, composed of nine small-size dual mirror (SST-2M) telescopes, has been proposed to be installed at the southern site of the Cherenkov Telescope Array (CTA), as a set of preproduction units of the CTA observatory. The ASTRI mini-array is a collaborative and international effort carried out by Italy, Brazil and South Africa and led by the Italian National Institute of Astrophysics, INAF. We present the main features of the current implementation of the Mini-Array Software System (MASS) now in use for the activities of the ASTRI SST-2M telescope prototype located at the INAF observing station on Mt. Etna, Italy and the characteristics that make it a prototype for the CTA control software system. CTA Data Management (CTADATA) and CTA Array Control and Data Acquisition (CTA-ACTL) requirements and guidelines as well as the ASTRI use cases were considered in the MASS design, most of its features are derived from the Atacama Large Millimeter/sub-millimeter Array Control software. The MASS will provide a set of tools to manage all onsite operations of the ASTRI mini-array in order to perform the observations specified in the short term schedule (including monitoring and controlling all the hardware components of each telescope and calibration device), to analyze the acquired data online and to store/retrieve all the data products to/from the onsite repository.

STS103-S-001

NASA Image and Video Library

1999-08-01

STS103-S-001 (August 1999) --- Designed by the crew members, the STS-103 emblem depicts the space shuttle Discovery approaching the Hubble Space Telescope (HST) prior to its capture and berthing. The purpose of the mission is to remove and replace some of the Telescope's older and out-of-date systems with newer, more reliable and more capable ones, and to make repairs to HST's exterior thermal insulation that has been damaged by more than nine years of exposure to the space environment. The horizontal and vertical lines centered on the telescope symbolize the ability to reach and maintain a desired attitude in space, essential to the instrument's scientific operation. The preservation of this ability is one of the primary objectives of the mission. After the flight, the telescope will resume its successful exploration of deep space and will continue to be used to study solar system objects, stars in the making, late phases of stellar evolution, galaxies and the early history of the universe. HST, as represented on this emblem was inspired by views from previous servicing missions, with its solar arrays illuminated by the sun, providing a striking contrast with the blackness of space and the night side of Earth. The NASA insignia design for space shuttle flights is reserved for use by the astronauts and for other official use as the NASA Administrator may authorize. Public availability has been approved only in the forms of illustrations by the various news media. When and if there is any change in this policy, which is not anticipated, the change will be publicly announced. Photo credit: NASA

An image-based array trigger for imaging atmospheric Cherenkov telescope arrays

NASA Astrophysics Data System (ADS)

Dickinson, Hugh; Krennrich, Frank; Weinstein, Amanda; Eisch, Jonathan; Byrum, Karen; Anderson, John; Drake, Gary

2018-05-01

It is anticipated that forthcoming, next generation, atmospheric Cherenkov telescope arrays will include a number of medium-sized telescopes that are constructed using a dual-mirror Schwarzschild-Couder configuration. These telescopes will sample a wide (8 °) field of view using a densely pixelated camera comprising over 104 individual readout channels. A readout frequency congruent with the expected single-telescope trigger rates would result in substantial data rates. To ameliorate these data rates, a novel, hardware-level Distributed Intelligent Array Trigger (DIAT) is envisioned. A copy of the DIAT operates autonomously at each telescope and uses reduced resolution imaging data from a limited subset of nearby telescopes to veto events prior to camera readout and any subsequent network transmission of camera data that is required for centralized storage or aggregation. We present the results of Monte-Carlo simulations that evaluate the efficacy of a "Parallax width" discriminator that can be used by the DIAT to efficiently distinguish between genuine gamma-ray initiated events and unwanted background events that are initiated by hadronic cosmic rays.

The hybrid energy spectrum of Telescope Array's Middle Drum Detector and surface array

NASA Astrophysics Data System (ADS)

Abbasi, R. U.; Abe, M.; Abu-Zayyad, T.; Allen, M. G.; Anderson, R.; Azuma, R.; Barcikowski, E.; Belz, J. W.; Bergman, D. R.; Blake, S. A.; Cady, R.; Chae, M. J.; Cheon, B. G.; Chiba, J.; Chikawa, M.; Cho, W. R.; Fujii, T.; Fukushima, M.; Goto, T.; Hanlon, W.; Hayashi, Y.; Hayashida, N.; Hibino, K.; Honda, K.; Ikeda, D.; Inoue, N.; Ishii, T.; Ishimori, R.; Ito, H.; Ivanov, D.; Jui, C. C. H.; Kadota, K.; Kakimoto, F.; Kalashev, O.; Kasahara, K.; Kawai, H.; Kawakami, S.; Kawana, S.; Kawata, K.; Kido, E.; Kim, H. B.; Kim, J. H.; Kim, J. H.; Kitamura, S.; Kitamura, Y.; Kuzmin, V.; Kwon, Y. J.; Lan, J.; Lim, S. I.; Lundquist, J. P.; Machida, K.; Martens, K.; Matsuda, T.; Matsuyama, T.; Matthews, J. N.; Minamino, M.; Mukai, K.; Myers, I.; Nagasawa, K.; Nagataki, S.; Nakamura, T.; Nonaka, T.; Nozato, A.; Ogio, S.; Ogura, J.; Ohnishi, M.; Ohoka, H.; Oki, K.; Okuda, T.; Ono, M.; Oshima, A.; Ozawa, S.; Park, I. H.; Pshirkov, M. S.; Rodriguez, D. C.; Rubtsov, G.; Ryu, D.; Sagawa, H.; Sakurai, N.; Sampson, A. L.; Scott, L. M.; Shah, P. D.; Shibata, F.; Shibata, T.; Shimodaira, H.; Shin, B. K.; Shin, H. S.; Smith, J. D.; Sokolsky, P.; Springer, R. W.; Stokes, B. T.; Stratton, S. R.; Stroman, T. A.; Suzawa, T.; Takamura, M.; Takeda, M.; Takeishi, R.; Taketa, A.; Takita, M.; Tameda, Y.; Tanaka, H.; Tanaka, K.; Tanaka, M.; Thomas, S. B.; Thomson, G. B.; Tinyakov, P.; Tkachev, I.; Tokuno, H.; Tomida, T.; Troitsky, S.; Tsunesada, Y.; Tsutsumi, K.; Uchihori, Y.; Udo, S.; Urban, F.; Vasiloff, G.; Wong, T.; Yamane, R.; Yamaoka, H.; Yamazaki, K.; Yang, J.; Yashiro, K.; Yoneda, Y.; Yoshida, S.; Yoshii, H.; Zollinger, R.; Zundel, Z.

2015-08-01

The Telescope Array experiment studies ultra high energy cosmic rays using a hybrid detector. Fluorescence telescopes measure the longitudinal development of the extensive air shower generated when a primary cosmic ray particle interacts with the atmosphere. Meanwhile, scintillator detectors measure the lateral distribution of secondary shower particles that hit the ground. The Middle Drum (MD) fluorescence telescope station consists of 14 telescopes from the High Resolution Fly's Eye (HiRes) experiment, providing a direct link back to the HiRes measurements. Using the scintillator detector data in conjunction with the telescope data improves the geometrical reconstruction of the showers significantly, and hence, provides a more accurate reconstruction of the energy of the primary particle. The Middle Drum hybrid spectrum is presented and compared to that measured by the Middle Drum station in monocular mode. Further, the hybrid data establishes a link between the Middle Drum data and the surface array. A comparison between the Middle Drum hybrid energy spectrum and scintillator Surface Detector (SD) spectrum is also shown.

Instrumentation for single-dish observations with The Greenland Telescope

NASA Astrophysics Data System (ADS)

Grimes, Paul K.; Asada, K.; Blundell, R.; Burgos, R.; Chang, H.-H.; Chen, M. T.; Goldie, D.; Groppi, C.; Han, C. C.; Ho, P. T. P.; Huang, Y. D.; Inoue, M.; Kubo, D.; Koch, P.; Leech, J.; de Lera Acedo, E.; Martin-Cocher, P.; Nishioka, H.; Nakamura, M.; Matsushita, S.; Paine, S. N.; Patel, N.; Raffin, P.; Snow, W.; Sridharan, T. K.; Srinivasan, R.; Thomas, C. N.; Tong, E.; Wang, M.-J.; Wheeler, C.; Withington, S.; Yassin, G.; Zeng, L.-Z.

2014-07-01

The Greenland Telescope project will deploy and operate a 12m sub-millimeter telescope at the highest point of the Greenland i e sheet. The Greenland Telescope project is a joint venture between the Smithsonian As- trophysical Observatory (SAO) and the Academia Sinica Institute of Astronomy and Astrophysics (ASIAA). In this paper we discuss the concepts, specifications, and science goals of the instruments being developed for single-dish observations with the Greenland Telescope, and the coupling optics required to couple both them and the mm-VLBI receivers to antenna. The project will outfit the ALMA North America prototype antenna for Arctic operations and deploy it to Summit Station,1 a NSF operated Arctic station at 3,100m above MSL on the Greenland I e Sheet. This site is exceptionally dry, and promises to be an excellent site for sub-millimeter astronomical observations. The main science goal of the Greenland Telescope is to carry out millimeter VLBI observations alongside other telescopes in Europe and the Americas, with the aim of resolving the event horizon of the super-massive black hole at the enter of M87. The Greenland Telescope will also be outfitted for single-dish observations from the millimeter-wave to Tera-hertz bands. In this paper we will discuss the proposed instruments that are currently in development for the Greenland Telescope - 350 GHz and 650 GHz heterodyne array receivers; 1.4 THz HEB array receivers and a W-band bolometric spectrometer. SAO is leading the development of two heterodyne array instruments for the Greenland Telescope, a 48- pixel, 325-375 GHz SIS array receiver, and a 4 pixel, 1.4 THz HEB array receiver. A key science goal for these instruments is the mapping of ortho and para H2D+ in old protostellar ores, as well as general mapping of CO and other transitions in molecular louds. An 8-pixel prototype module for the 350 GHz array is currently being built for laboratory and operational testing on the Greenland Telescope. Arizona State University are developing a 650 GHz 256 pixel SIS array receiver based on the KAPPa SIS mixer array technology and ASIAA are developing 1.4 THz HEB single pixel and array receivers. The University of Cambridge and SAO are collaborating on the development of the CAMbridge Emission Line Surveyor (CAMELS), a W-band `on- hip' spectrometer instrument with a spectral resolution of R ~ 3000. CAMELS will consist of two pairs of horn antennas, feeding super conducting niobium nitride filter banks read by tantalum based Kinetic Inductance Detectors.

NuSTAR Stares at the Sun

NASA Image and Video Library

2015-07-08

Flaring, active regions of our sun are highlighted in this image combining observations from several telescopes. High-energy X-rays from NASA's Nuclear Spectroscopic Telescope Array (NuSTAR) are shown in blue; low-energy X-rays from Japan's Hinode spacecraft are green; and extreme ultraviolet light from NASA's Solar Dynamics Observatory (SDO) is yellow and red. All three telescopes captured their solar images around the same time on April 29, 2015. The NuSTAR image is a mosaic made from combining smaller images. The active regions across the sun's surface contain material heated to several millions of degrees. The blue-white areas showing the NuSTAR data pinpoint the most energetic spots. During the observations, microflares went off, which are smaller versions of the larger flares that also erupt from the sun's surface. The microflares rapidly release energy and heat the material in the active regions. NuSTAR typically stares deeper into the cosmos to observe X-rays from supernovas, black holes and other extreme objects. But it can also look safely at the sun and capture images of its high-energy X-rays with more sensitivity than before. Scientists plan to continue to study the sun with NuSTAR to learn more about microflares, as well as hypothesized nanoflares, which are even smaller. In this image, the NuSTAR data shows X-rays with energies between 2 and 6 kiloelectron volts; the Hinode data, which is from the X-ray Telescope instrument, has energies of 0.2 to 2.4 kiloelectron volts; and the Solar Dynamics Observatory data, taken using the Atmospheric Imaging Assembly instrument, shows extreme ultraviolet light with wavelengths of 171 and 193 Angstroms. Note the green Hinode image frame edge does not extend as far as the SDO ultraviolet image, resulting in the green portion of the image being truncated on the right and left sides. http://photojournal.jpl.nasa.gov/catalog/PIA19821

LSPECS: A Proposed Robotic Astronomy Mission to the Lunar South Polar Regions

NASA Technical Reports Server (NTRS)

Lowman, Paul D., Jr.

2003-01-01

This paper outlines a possible mission to emplace a robotic infrared/submillimeter wave interferometer array near the lunar south pole. This region has now been investigated by the Clementine and Lunar Prospector missions, and by Earth-based radar, and its topography and thermal environment are fairly well-known. The area would be exceptionally suitable for infrared/submillimeter astronomy because of the continually low temperatures, approaching that of liquid nitrogen (77K) in some places. The presence of ice has been inferred independently from Clementine and Lunar Prospector, providing another incentive for a south polar mission. A submillimeter spaceborne interferometer mission, Submillimeter Probe of the Evolution of the Cosmic Structure (SPECS) has been proposed by John Mather and others, covering the 40 - 500 micron region with 3 formation flying telescopes. The present paper proposes a lunar adaptation of the SPECS concept, LSPECS. This adaptation would involve landing 4 telescopes on the area north of Shackleton crater at zero degrees longitude. This is in nearly year round darkness but is continually radar visible from Earth. The landed payload of LSPECS would include a telerobotic rover, 4 three meter submm telescopes, a solar power array to be emplaced on the continually sunlit north rim of Shackleton crater, and an S-band antenna for data relay to Earth. Operation without the use of expendable cryogenics for cooling might be possible, trading long exposure time for instrument temperatures above that of liquid helium. The LSPECS would permit long-term study of an extremely wide range of cosmic and solar system phenomena in the southern celestial hemisphere. For complete sky coverage, a similar installation near the north pole would be required. The LSPECS site would also be suitable other types of observation, such as optical interferometry or centimeter wavelength radio astronomy. The lunar south pole is also of great interest because of its extensive ice deposits, which may represent cometary infall with pre-biotic compounds.

On-Orbit Reconfigurable Solar Array

NASA Technical Reports Server (NTRS)

Levy, Robert K. (Inventor)

2017-01-01

In one or more embodiments, the present disclosure teaches a method for reconfiguring a solar array. The method involves providing, for the solar array, at least one string of solar cells. The method further involves deactivating at least a portion of at least one of the strings of solar cells of the solar array when power produced by the solar array reaches a maximum power allowance threshold. In addition, the method involves activating at least a portion of at least one of the strings of the solar cells in the solar array when the power produced by the solar array reaches a minimum power allowance threshold.

Pierre Auger Observatory and Telescope Array: Joint Contributions to the 33rd International Cosmic Ray Conference (ICRC 2013)

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

Abu-Zayyad, T.; et al.

2013-10-02

Joint contributions of the Pierre Auger and Telescope Array Collaborations to the 33rd International Cosmic Ray Conference, Rio de Janeiro, Brazil, July 2013: cross-calibration of the fluorescence telescopes, large scale anisotropies and mass composition.

Composition Studies with the Telescope Array Surface Detector

NASA Astrophysics Data System (ADS)

Kuznetsov, Mikhail; Piskunov, Maxim; Rubtsov, Grigory; Troitsky, Sergey; Zhezher, Yana

The results on ultra-high-energy cosmic-ray chemical composition based on the data from the Telescope Array surface-detector are presented. The method is based on the multivariate boosted decision tree (BDT) analysis which uses surface-detector observables. The results on average atomic mass in the energy range 1018.0-1020.0 eV are presented. A comparison with the Telescope Array hybrid results and the Pierre Auger Observatory surface detector results is shown.

Secondary mirror system for the European Solar Telescope (EST)

NASA Astrophysics Data System (ADS)

Cavaller, L.; Siegel, B.; Prieto, G.; Hernandez, E.; Casalta, J. M.; Mercader, J.; Barriga, J.

2010-07-01

The European Solar Telescope (EST) is a European collaborative project to build a 4m class solar telescope in the Canary Islands, which is now in its design study phase. The telescope will provide diffraction limited performance for several instruments observing simultaneously at the Coudé focus at different wavelengths. A multi-conjugated adaptive optics system composed of a tip-tilt mirror and several deformable mirrors will be integrated in the telescope optical path. The secondary mirror system is composed of the mirror itself (Ø800mm), the alignment drives and the cooling system needed to remove the solar heat load from the mirror. During the design study the feasibility to provide fast tip-tilt capabilities at the secondary mirror to work as the adaptive optics tip-tilt mirror is also being evaluated.

Solar System Studies with the Space Infrared Telescope Facility (SIRTF)

NASA Technical Reports Server (NTRS)

Cruikshank, Dale P.; DeVincenzi, Donald L. (Technical Monitor)

1998-01-01

SIRTF (Space Infrared Telescope Facility) is the final element in NASA's 'Great Observatories' program. It consists of an 85-cm cryogenically-cooled observatory for infrared astronomy from space. SIRTF is scheduled for launch in late 2001 or early 2002 on a Delta rocket into a heliocentric orbit trailing the Earth. Data from SIRTF will be processed and disseminated to the community through the SIRTF Science Center (SSC) located at the Infrared Processing and Analysis Center (IPAC) at Caltech. Some 80/% of the total observing time (estimated at a minimum of 7500 hours of integration time per year for the mission lifetime of about 4 years) will be available to the scientific community at large through a system of refereed proposals. Three basic instruments are located in the SIRTF focal plane. The Multiband Imaging Photometer (MIPS), the Infrared Array Camera (IRAC), and the Infrared Spectrometer (IRS), taken together, provide imaging and spectroscopy from 3.5 to 160 microns. Among the solar system studies suited to SIRTF are the following: 1) spectroscopy and radiometry of small bodies from the asteroid main belt, through the Trojan clouds, to the Kuiper Disk; 2) dust distribution in the zodiacal cloud and the Earth's heliocentric dust ring; 3) spectroscopy and radiometry of comets; and 4) spectroscopy and radiometry of planets and their satellites. Searches for, and studies of dust disks around other stars, brown dwarfs, and superplanets will also be conducted with SIRTF. The SORTIE web site (http://ssc.ipac.caltech.edu/sirtf) contains important details and documentation on the project, the spacecraft, the telescope, instruments, and observing procedures. A community-wide workshop for solar system studies with SIRTF is in the planning stages by the author and Martha S. Hanner for the summer of 1999.

Solar array technology evaluation program for SEPS (Solar Electrical Propulsion Stage)

NASA Technical Reports Server (NTRS)

1974-01-01

An evaluation of the technology and the development of a preliminary design for a 25 kilowatt solar array system for solar electric propulsion are discussed. The solar array has a power to weight ratio of 65 watts per kilogram. The solar array system is composed of two wings. Each wing consists of a solar array blanket, a blanket launch storage container, an extension/retraction mast assembly, a blanket tensioning system, an array electrical harness, and hardware for supporting the system for launch and in the operating position. The technology evaluation was performed to assess the applicable solar array state-of-the-art and to define supporting research necessary to achieve technology readiness for meeting the solar electric propulsion system solar array design requirements.

Solar System Observing with the Space Infrared Telescope Facility (SIRTF)

NASA Technical Reports Server (NTRS)

Cleve, J. Van; Meadows, V. S.; Stansberry, J.

2003-01-01

SIRTF is NASA's Space Infrared Telescope Facility. Currently planned for launch on 15 Apr 2003, it is the final element in NASA's Great Observatories Program. SIRTF has an 85 cm diameter f/12 lightweight beryllium telescope, cooled to lekss than 5.5K. It is diffraction-limited at 6.5 microns, and has wavelengthcoverage from 3-180 microns. Its estimated lifetime (limited by cryogen) is 2.5 years at minimum, with a goal of 5+ years. SIRTF has three instruments, IRAC, IRS, and MIPS. IRAC (InfraRed Array Camera) provides simultaneous images at wavelengths of 3.6, 4.5, 5.8, and 8.0 microns. IRS (InfraRed Spectrograph) has 4 modules providing low-resolution (R=60-120) spectra from 5.3 to 40 microns, high-resolution (R=600) spectra from 10 to 37 microns, and an autonomous target acquisition system (PeakUp) which includes small-field imaging at 15 microns. MIPS (Multiband Imaging Photometer for SIRTF)} does imaging photometry at 24, 70, and 160 m and low-resolution (R=15-25) spectroscopy (SED) between 55 and 96 microns. The SIRTF Guaranteed Time Observers (GTOs) are planning to observe Outer Solar System satellites and planets, extinct comets and low-albedo asteroids, Centaurs and Kuiper Belt Objects, cometary dust trails, and a few active short-period comets. The GTO programs are listed in detail in the SIRTF Reserved Observations Catalog (ROC). We would like to emphasize that there remain many interesting subjects for the General Observers (GO). Proposal success for the planetary observer community in the first SIRTF GO proposal cycle (GO-1) determines expectations for future GO calls and Solar System use of SIRTF, so we would like promote a strong set of planetary GO-1 proposals. Towards that end, we present this poster, and we will convene a Solar System GO workshop 3.5 months after launch.

Overview of the Atacama Cosmology Telescope: Receiver, Instrumentation, and Telescope Systems

NASA Astrophysics Data System (ADS)

Swetz, D. S.; Ade, P. A. R.; Amiri, M.; Appel, J. W.; Battistelli, E. S.; Burger, B.; Chervenak, J.; Devlin, M. J.; Dicker, S. R.; Doriese, W. B.; Dünner, R.; Essinger-Hileman, T.; Fisher, R. P.; Fowler, J. W.; Halpern, M.; Hasselfield, M.; Hilton, G. C.; Hincks, A. D.; Irwin, K. D.; Jarosik, N.; Kaul, M.; Klein, J.; Lau, J. M.; Limon, M.; Marriage, T. A.; Marsden, D.; Martocci, K.; Mauskopf, P.; Moseley, H.; Netterfield, C. B.; Niemack, M. D.; Nolta, M. R.; Page, L. A.; Parker, L.; Staggs, S. T.; Stryzak, O.; Switzer, E. R.; Thornton, R.; Tucker, C.; Wollack, E.; Zhao, Y.

2011-06-01

The Atacama Cosmology Telescope was designed to measure small-scale anisotropies in the cosmic microwave background and detect galaxy clusters through the Sunyaev-Zel'dovich effect. The instrument is located on Cerro Toco in the Atacama Desert, at an altitude of 5190 m. A 6 m off-axis Gregorian telescope feeds a new type of cryogenic receiver, the Millimeter Bolometer Array Camera. The receiver features three 1000-element arrays of transition-edge sensor bolometers for observations at 148 GHz, 218 GHz, and 277 GHz. Each detector array is fed by free space millimeter-wave optics. Each frequency band has a field of view of approximately 22' × 26'. The telescope was commissioned in 2007 and has completed its third year of operations. We discuss the major components of the telescope, camera, and related systems, and summarize the instrument performance.

Report of the Working Design Group

NASA Technical Reports Server (NTRS)

1992-01-01

The engineering study group in the LOUISA workshop was responsible for producing a preliminary general design for an optical synthetic aperture telescope on the Moon. This design is intended to be a test case for focusing continuing design studies. The scope of the design included consideration of the array geometry, individual telescopes, metrology, site attributes, and construction. However, no attempt was made to go into further depth in the design than to cover the essential characteristics of the instrument. The starting point for the array design was the lunar optical array discussed by Burke (1985). His array geometry followed the design and correlation procedure of the 27-element Very Large Array (VLA) radio telescopes near Socorro, New Mexico.

Vacuum Ultraviolet Radiation and Atomic Oxygen Durability Evaluation of HST Bi-Stem Thermal Shield Materials

NASA Technical Reports Server (NTRS)

Dever, Joyce; deGroh, Kim K.

2002-01-01

Bellows-type thermal shields were used on the bi-stems of replacement solar arrays installed on the Hubble Space Telescope (HST) during the first HST servicing mission (SMI) in December 1993. These thermal shields helped reduce the problem of thermal gradient- induced jitter observed with the original HST solar arrays during orbital thermal cycling and have been in use on HST for eight years. This paper describes ground testing of the candidate solar array bi-stem thermal shield materials including backside aluminized Teflon(R)FEP (fluorinated ethylene propylene) with and without atomic oxygen (AO) and ultraviolet radiation protective surface coatings for durability to AO and combined AO and vacuum ultraviolet (VOV) radiation. NASA Glenn Research Center (GRC) conducted VUV and AO exposures of samples of candidate thermal shield materials at HST operational temperatures and pre- and post-exposure analyses as part of an overall program coordinated by NASA Goddard Space Flight Center (GSFC) to determine the on-orbit durability of these materials. Coating adhesion problems were observed for samples having the AO- and combined AO/UV-protective coatings. Coating lamination occurred with rapid thermal cycling testing which simulated orbital thermal cycling. This lack of adhesion caused production of coating flakes from the material that would have posed a serious risk to HST optics if the coated materials were used for the bi-stem thermal shields. No serious degradation was observed for the uncoated aluminized Teflon(R) as evaluated by optical microscopy, although atomic force microscopy (AFM) microhardness testing revealed that an embrittled surface layer formed on the uncoated Teflon(R) surface due to vacuum ultraviolet radiation exposure. This embrittled layer was not completely removed by AO erosion, No cracks or particle flakes were produced for the embrittled uncoated material upon exposure to VUV and AO at operational temperatures to an equivalent exposure of approximately five years in the HST environment. Uncoated aluminized FEP Teflon(R) was determined to be the most appropriate thermal shield material and was used on the bi-stems of replacement solar arrays installed on HST during SMI in December 1993. The SMI -installed solar arrays air scheduled to be replaced during MST's fourth servicing mission (SM3B) in early 2002.

Discovery of the Accretion-Powered Millisecond Pulsar SWIFT 51756.9-2508 with a Low-Mass Companion

NASA Technical Reports Server (NTRS)

Krimm, H.A.; Markwardt, C.B.; Deloye, C.J.; Romano, P.; Chakrabarty, S.; Campana. S.; Cummings, J.C.; Galloway, D.K.; Gehrels, N.; Hartman, J.M.;

Pulsars Probe the Low-Frequency Gravitational Sky: Pulsar Timing Arrays Basics and Recent Results

NASA Astrophysics Data System (ADS)

Tiburzi, Caterina

2018-03-01

Pulsar Timing Array experiments exploit the clock-like behaviour of an array of millisecond pulsars, with the goal of detecting low-frequency gravitational waves. Pulsar Timing Array experiments have been in operation over the last decade, led by groups in Europe, Australia, and North America. These experiments use the most sensitive radio telescopes in the world, extremely precise pulsar timing models and sophisticated detection algorithms to increase the sensitivity of Pulsar Timing Arrays. No detection of gravitational waves has been made to date with this technique, but Pulsar Timing Array upper limits already contributed to rule out some models of galaxy formation. Moreover, a new generation of radio telescopes, such as the Five hundred metre Aperture Spherical Telescope and, in particular, the Square Kilometre Array, will offer a significant improvement to the Pulsar Timing Array sensitivity. In this article, we review the basic concepts of Pulsar Timing Array experiments, and discuss the latest results from the established Pulsar Timing Array collaborations.

Curved CCD detector devices and arrays for multispectral astrophysical applications and terrestrial stereo panoramic cameras

NASA Astrophysics Data System (ADS)

Swain, Pradyumna; Mark, David

2004-09-01

The emergence of curved CCD detectors as individual devices or as contoured mosaics assembled to match the curved focal planes of astronomical telescopes and terrestrial stereo panoramic cameras represents a major optical design advancement that greatly enhances the scientific potential of such instruments. In altering the primary detection surface within the telescope"s optical instrumentation system from flat to curved, and conforming the applied CCD"s shape precisely to the contour of the telescope"s curved focal plane, a major increase in the amount of transmittable light at various wavelengths through the system is achieved. This in turn enables multi-spectral ultra-sensitive imaging with much greater spatial resolution necessary for large and very large telescope applications, including those involving infrared image acquisition and spectroscopy, conducted over very wide fields of view. For earth-based and space-borne optical telescopes, the advent of curved CCD"s as the principle detectors provides a simplification of the telescope"s adjoining optics, reducing the number of optical elements and the occurrence of optical aberrations associated with large corrective optics used to conform to flat detectors. New astronomical experiments may be devised in the presence of curved CCD applications, in conjunction with large format cameras and curved mosaics, including three dimensional imaging spectroscopy conducted over multiple wavelengths simultaneously, wide field real-time stereoscopic tracking of remote objects within the solar system at high resolution, and deep field survey mapping of distant objects such as galaxies with much greater multi-band spatial precision over larger sky regions. Terrestrial stereo panoramic cameras equipped with arrays of curved CCD"s joined with associative wide field optics will require less optical glass and no mechanically moving parts to maintain continuous proper stereo convergence over wider perspective viewing fields than their flat CCD counterparts, lightening the cameras and enabling faster scanning and 3D integration of objects moving within a planetary terrain environment. Preliminary experiments conducted at the Sarnoff Corporation indicate the feasibility of curved CCD imagers with acceptable electro-optic integrity. Currently, we are in the process of evaluating the electro-optic performance of a curved wafer scale CCD imager. Detailed ray trace modeling and experimental electro-optical data performance obtained from the curved imager will be presented at the conference.

International ultraviolet explorer solar array power degradation

NASA Technical Reports Server (NTRS)

Day, J. H., Jr.

1983-01-01

The characteristic electrical performance of each International Ultraviolet Explorer (IUE) solar array panel is evaluated as a function of several prevailing variables (namely, solar illumination, array temperature and solar cell radiation damage). Based on degradation in the current-voltage characteristics of the array due to solar cell damage accumulated over time by space charged particle radiations, the available IUE solar array power is determined for life goals up to 10 years. Best and worst case calculations are normalized to actual IUE flight data (available solar array power versus observatory position) to accurately predict the future IUE solar array output. It is shown that the IUE solar array can continue to produce more power than is required at most observatory positions for at least 5 more years.

Observing the 2017 Total Solar Eclipse from the Pisgah Astronomical Research Institute

NASA Astrophysics Data System (ADS)

Kirwan, Sean Matthew; Cline, J. Donald; Krochmal, Mark; Donald Cline, Mark Krochmal

2017-01-01

The Pisgah Astronomical Research Institute (PARI) is located directly under the path of totality of next year’s solar eclipse and possesses two 26m radio telescopes capable of interferometry at simultaneously at 2.3 GHz and 8.4 GHZ. PARI is preparing these radio telescopes for use by the astronomical community to observe solar eclipse. We will present the status of PARI’s radio telescopes and information on access for the eclipse. We will also present the status and availability of several optical telescopes.

VERITAS: status c.2005

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

Weekes, T. C.; Atkins, R. W.; Badran, H. M.

2006-07-11

VERITAS (Very Energetic Radiation Imaging Telescope Array System), is one of a new generation of TeV gamma-ray observatories. The current status of its construction is described here. The first two telescopes and cameras have been completed and meet the design specifications; the full array of four telescopes could be operational by the end of 2006.

Microsystem enabled photovoltaic modules and systems

DOEpatents

Nielson, Gregory N.; Sweatt, William C.; Okandan, Murat

2017-09-12

A photovoltaic (PV) module includes an absorber layer coupled to an optic layer. The absorber layer includes an array of PV elements. The optic layer includes a close-packed array of Keplerian telescope elements, each corresponding to one of an array of pupil elements. The Keplerian telescope substantially couple radiation that is incident on their objective surfaces into the corresponding pupil elements. Each pupil element relays radiation that is coupled into it from the corresponding Keplerian telescope element into the corresponding PV element.

Jupiter's Decameter Radiation as Viewed from Juno, Cassini, WIND, STEREO A, and Earth-Based Radio Observatories

NASA Astrophysics Data System (ADS)

Imai, Masafumi; Kurth, William S.; Hospodarsky, George B.; Bolton, Scott J.; Connerney, John E. P.; Levin, Steven M.; Clarke, Tracy E.; Higgins, Charles A.

2017-04-01

Jupiter is the dominant auroral radio source in our solar system, producing decameter (DAM) radiation (from a few to 40 MHz) with a flux density of up to 10-19 W/(m2Hz). Jovian DAM non-thermal radiation above 10 MHz is readily observed by Earth-based radio telescopes that are limited at lower frequencies by terrestrial ionospheric conditions and radio frequency interference. In contrast, frequencies observed by spacecraft depend upon receiver capability and the ambient solar wind plasma frequency. Observations of DAM from widely separated observers can be used to investigate the geometrical properties of the beam and learn about the generation mechanism. The first multi-observer observations of Jovian DAM emission were made using the Voyager spacecraft and ground-based radio telescopes in early 1979, but, due to geometrical constraints and limited flyby duration, a full understanding of the latitudinal beaming of Jovian DAM radiation remains elusive. This understanding is sorely needed to confirm DAM generation by the electron cyclotron maser instability, the widely assumed generation mechanism. Juno first detected Jovian DAM emissions on May 5, 2016, on approach to the Jovian system, initiating a new opportunity to perform observations of Jovian DAM radiation with Juno, Cassini, WIND, STEREO A, and Earth-based radio observatories (Long Wavelength Array Station One (LWA1) in New Mexico, USA, and Nançay Decameter Array (NDA) in France). These observers are widely distributed throughout our solar system and span a broad frequency range of 3.5 to 40.5 MHz. Juno resides in orbit at Jupiter, Cassini at Saturn, WIND around Earth, STEREO A in 1 AU orbit, and LWA1 and NDA at Earth. Juno's unique polar trajectory is expected to facilitate extraordinary stereoscopic observations of Jovian DAM, leading to a much improved understanding of the latitudinal beaming of Jovian DAM.

Thermal Vacuum/Balance Test Results of Swift BAT with Loop Heat Pipe Thermal System

NASA Technical Reports Server (NTRS)

Choi, Michael K.

2004-01-01

The Swift Burst Alert Telescope (BAT) Detector Array is thermally well coupled to eight constant conductance heat pipes (CCHPs) embedded in the Detector Array Plate PAP), and two loop heat pipes (LHPs) transport heat from the CCHPs to a radiator. The CCHPs have ammonia as the working fluid and the LHPs have propylene as the working fluid. Precision heater controllers, which have adjustable set points in flight, are used to control the LHP compensation chamber and Detector Array xA1 ASIC temperatures. The radiator has AZ-Tek's AZW-LA-II low solar absorptance white paint as the thermal coating, and is located on the anti-sun side of the spacecraft. A thermal balance (T/B) test on the BAT was successfully completed. It validated that the thermal design satisfies the temperature requirements of the BAT in the flight thermal environments. Instrument level and observatory level thermal vacuum (TN) cycling tests of the BAT Detector Array by using the LHP thermal system were successfully completed. This paper presents the results of the T/B test and T N cycling tests.

Evaluation of solar cells and arrays for potential solar power satellite applications

NASA Technical Reports Server (NTRS)

Almgren, D. W.; Csigi, K.; Gaudet, A. D.

1978-01-01

Proposed solar array designs and manufacturing methods are evaluated to identify options which show the greatest promise of leading up to the develpment of a cost-effective SPS solar cell array design. The key program elements which have to be accomplished as part of an SPS solar cell array development program are defined. The issues focussed on are: (1) definition of one or more designs of a candidate SPS solar array module, using results from current system studies; (2) development of the necessary manufacturing requirements for the candidate SPS solar cell arrays and an assessment of the market size, timing, and industry infrastructure needed to produce the arrays for the SPS program; (3) evaluation of current DOE, NASA and DOD photovoltaic programs to determine the impacts of recent advances in solar cell materials, array designs and manufacturing technology on the candidate SPS solar cell arrays; and (4) definition of key program elements for the development of the most promising solar cell arrays for the SPS program.

The First Multichroic Polarimeter Array on the Atacama Cosmology Telescope: Characterization and Performance

NASA Technical Reports Server (NTRS)

Ho, S. P.; Pappas, C. G.; Austermann, J.; Beall, J. A.; Becker, D.; Choi, S. K.; Datta, R.; Duff, S. M.; Gallardo, P. A.; Grace, E.;

The First Multichroic Polarimeter Array on the Atacama Cosmology Telescope: Characterization and Performance

NASA Astrophysics Data System (ADS)

Ho, S. P.; Pappas, C. G.; Austermann, J.; Beall, J. A.; Becker, D.; Choi, S. K.; Datta, R.; Duff, S. M.; Gallardo, P. A.; Grace, E.; Hasselfield, M.; Henderson, S. W.; Hilton, G. C.; Hubmayr, J.; Koopman, B. J.; Lanen, J. V.; Li, D.; McMahon, J.; Nati, F.; Niemack, M. D.; Niraula, P.; Salatino, M.; Schillaci, A.; Schmitt, B. L.; Simon, S. M.; Staggs, S. T.; Stevens, J. R.; Ward, J. T.; Wollack, E. J.; Vavagiakis, E. M.

2016-08-01

The Atacama Cosmology Telescope Polarimeter (ACTPol) is a polarization sensitive receiver for the 6-m Atacama Cosmology Telescope (ACT) and measures the small angular scale polarization anisotropies in the cosmic microwave background (CMB). The full focal plane is composed of three detector arrays, containing over 3000 transition edge sensors (TES detectors) in total. The first two detector arrays, observing at 146 GHz, were deployed in 2013 and 2014, respectively. The third and final array is composed of multichroic pixels sensitive to both 90 and 146 GHz and saw first light in February 2015. Fabricated at NIST, this dichroic array consists of 255 pixels, with a total of 1020 polarization sensitive bolometers and is coupled to the telescope with a monolithic array of broad-band silicon feedhorns. The detectors are read out using time-division SQUID multiplexing and cooled by a dilution refrigerator at 110 mK. We present an overview of the assembly and characterization of this multichroic array in the lab, and the initial detector performance in Chile. The detector array has a TES detector electrical yield of 85 %, a total array sensitivity of less than 10 \\upmu K√{ {s}}, and detector time constants and saturation powers suitable for ACT CMB observations.

Correlation tracking study for meter-class solar telescope on space shuttle. [solar granulation

NASA Technical Reports Server (NTRS)

Smithson, R. C.; Tarbell, T. D.

1977-01-01

The theory and expected performance level of correlation trackers used to control the pointing of a solar telescope in space using white light granulation as a target were studied. Three specific trackers were modeled and their performance levels predicted for telescopes of various apertures. The performance of the computer model trackers on computer enhanced granulation photographs was evaluated. Parametric equations for predicting tracker performance are presented.

Fiber-linked telescope array: description and laboratory tests of a two-channel prototype

NASA Astrophysics Data System (ADS)

Alleman, J. J.; Reynaud, F.; Connes, P.

1995-05-01

We present a complete two-telescope version of a fiber-linked coherent array that is meant to be used for mounting on the dish of a radio telescope. This was built with 20-cm amateur telescopes and includes three different servo subsystems for guiding, nulling of the air path difference, and fiber length control. Laboratory tests of the fully integrated system in front of a star simulator are described.

Multi-kW solar arrays for Earth orbit applications

NASA Technical Reports Server (NTRS)

1985-01-01

The multi-kW solar array program is concerned with developing the technology required to enable the design of solar arrays required to power the missions of the 1990's. The present effort required the design of a modular solar array panel consisting of superstrate modules interconnected to provide the structural support for the solar cells. The effort was divided into two tasks: (1) superstrate solar array panel design, and (2) superstrate solar array panel-to-panel design. The primary objective was to systematically investigate critical areas of the transparent superstrate solar array and evaluate the flight capabilities of this low cost approach.

Solar adaptive optics: specificities, lessons learned, and open alternatives

NASA Astrophysics Data System (ADS)

Montilla, I.; Marino, J.; Asensio Ramos, A.; Collados, M.; Montoya, L.; Tallon, M.

2016-07-01

First on sky adaptive optics experiments were performed on the Dunn Solar Telescope on 1979, with a shearing interferometer and limited success. Those early solar adaptive optics efforts forced to custom-develop many components, such as Deformable Mirrors and WaveFront Sensors, which were not available at that time. Later on, the development of the correlation Shack-Hartmann marked a breakthrough in solar adaptive optics. Since then, successful Single Conjugate Adaptive Optics instruments have been developed for many solar telescopes, i.e. the National Solar Observatory, the Vacuum Tower Telescope and the Swedish Solar Telescope. Success with the Multi Conjugate Adaptive Optics systems for GREGOR and the New Solar Telescope has proved to be more difficult to attain. Such systems have a complexity not only related to the number of degrees of freedom, but also related to the specificities of the Sun, used as reference, and the sensing method. The wavefront sensing is performed using correlations on images with a field of view of 10", averaging wavefront information from different sky directions, affecting the sensing and sampling of high altitude turbulence. Also due to the low elevation at which solar observations are performed we have to include generalized fitting error and anisoplanatism, as described by Ragazzoni and Rigaut, as non-negligible error sources in the Multi Conjugate Adaptive Optics error budget. For the development of the next generation Multi Conjugate Adaptive Optics systems for the Daniel K. Inouye Solar Telescope and the European Solar Telescope we still need to study and understand these issues, to predict realistically the quality of the achievable reconstruction. To improve their designs other open issues have to be assessed, i.e. possible alternative sensing methods to avoid the intrinsic anisoplanatism of the wide field correlation Shack-Hartmann, new parameters to estimate the performance of an adaptive optics solar system, alternatives to the Strehl and the Point Spread Function used in night time adaptive optics but not really suitable to the solar systems, and new control strategies more complex than the ones used in nowadays solar Multi Conjugate Adaptive Optics systems. In this paper we summarize the lessons learned with past and current solar adaptive optics systems and focus on the discussion on the new alternatives to solve present open issues limiting their performance.

Space Shuttle Projects

NASA Image and Video Library

2002-03-07

Inside the Space Shuttle Columbia's cabin, astronaut Nancy J. Currie, mission specialist, controlled the Remote Manipulator System (RMS) on the crew cabin's aft flight deck to assist fellow astronauts during the STS-109 mission Extra Vehicular Activities (EVA). The RMS was used to capture the telescope and secure it into Columbia's cargo bay. The Space Shuttle Columbia STS-109 mission lifted off March 1, 2002 with goals of repairing and upgrading the Hubble Space Telescope (HST). The Marshall Space Flight Center in Huntsville, Alabama had the responsibility for the design, development, and construction of the HST, which is the most powerful and sophisticated telescope ever built. STS-109 upgrades to the HST included: replacement of the solar array panels; replacement of the power control unit (PCU); replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS); and installation of the experimental cooling system for the Hubble's Near-Infrared Camera and Multi-object Spectrometer (NICMOS), which had been dormant since January 1999 when its original coolant ran out. Lasting 10 days, 22 hours, and 11 minutes, the STS-109 mission was the 108th flight overall in NASA's Space Shuttle Program.

Ghostly Specter Haunts the ‘Coldest Place in the Universe’

NASA Image and Video Library

2013-10-28

The Boomerang nebula, called the "coldest place in the universe," reveals its true shape to the Atacama Large Millimeter/submillimeter Array (ALMA) telescope. The background blue structure, as seen in visible light by NASA's Hubble Space Telescope, shows a classic double-lobe shape with a very narrow central region. ALMA’s resolution and ability to see the cold gas molecules reveals the nebula’s more elongated shape, as seen in red. Image credit: NRAO/AUI/NSF/NASA/STScI/JPL-Caltech Read more about this image from NASA's Jet Propulsion Laboratory (JPL) here: 1.usa.gov/17o22Rz 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

KSC-2012-1528

NASA Image and Video Library

2012-02-17

VANDENBERG AIR FORCE BASE, Calif. – Inside an environmental enclosure at Vandenberg Air Force Base's processing facility in California, solar panels line the sides of NASA's Nuclear Spectroscopic Telescope Array, or NuSTAR, spacecraft. NuSTAR is newly mated with its Orbital Sciences Pegasus XL rocket. The uniting of the spacecraft with the rocket is a major milestone in prelaunch preparations. After processing of the rocket and spacecraft are complete, they will be flown on Orbital's L-1011 carrier aircraft from Vandenberg to the Ronald Reagan Ballistic Missile Defense Test Site on the Pacific Ocean’s Kwajalein Atoll for launch. The high-energy x-ray telescope will conduct a census of black holes, map radioactive material in young supernovae remnants, and study the origins of cosmic rays and the extreme physics around collapsed stars. For more information, visit http://www.nasa.gov/nustar. Photo credit: NASA/Randy Beaudoin, VAFB

NECTAR: New electronics for the Cherenkov Telescope Array

NASA Astrophysics Data System (ADS)

Naumann, Christopher Lindsay; Bolmont, J.; Corona, P.; Delagnes, E.; Dzahini, D.; Feinstein, F.; Gascon, D.; Glicenstein, J.-F.; Nayman, P.; Rarbi, F.; Ribo, M.; Sanuy, A.; Siero, X.; Tavernet, J.-P.; Toussenel, F.; Vincent, P.; Vorobiov, S.

2012-12-01

The international CTA consortium is currently in the preparatory phase for the development of the next-generation Cherenkov Telescope Array (CTA [1]), based on the return of experience from the three major current-generation arrays H.E.S.S., MAGIC and VERITAS. To achieve an unprecedented sensitivity and energy range for TeV gamma rays, a new kind of flexible and powerful yet inexpensive front-end hardware will be required for the order of 105 channels of photodetectors in up to 100 telescopes. One possible solution is the NECTAr (New Electronics for the Cherenkov Telescope Array) system, based on the integration of as much as possible of the front-end electronics (amplifiers, fast analogue samplers, memory and ADCs) into a single ASIC for very fast readout performance and a significant reduction of the cost and the lower consumption per channel, while offering a high degree of flexibility both for the triggering and the readout of the telescope. The current status of its development is presented, along with newest results from measurements and simulation studies.

KSC-99pp0354

NASA Image and Video Library

1999-03-26

Viewed from above in the Vertical Processing Facility, the Chandra X-ray Observatory is seen with one of its solar panel arrays attached, at right. Formerly called the Advanced X-ray Astrophysics Facility, Chandra comprises three major elements: the spacecraft, the science instrument module (SIM), and the world's most powerful X-ray telescope. Chandra will allow scientists from around the world to see previously invisible black holes and high-temperature gas clouds, giving the observatory the potential to rewrite the books on the structure and evolution of our universe. Chandra is scheduled for launch July 9 aboard Space Shuttle Columbia, on mission STS-93

KSC-99pp0356

NASA Image and Video Library

1999-03-25

In the Vertical Processing Facility, TRW workers continue checking the deployment of the solar panel array (right) after attaching it to the Chandra X-ray Observatory (left). Formerly called the Advanced X-ray Astrophysics Facility, Chandra comprises three major elements: the spacecraft, the science instrument module (SIM), and the world's most powerful X-ray telescope. Chandra will allow scientists from around the world to see previously invisible black holes and high-temperature gas clouds, giving the observatory the potential to rewrite the books on the structure and evolution of our universe. Chandra is scheduled for launch July 9 aboard Space Shuttle Columbia, on mission STS-93

KSC-99pp0352

NASA Image and Video Library

1999-03-26

TRW technicians in the Vertical Processing Facility check the fitting of the solar panel array being attached to the Chandra X-ray Observatory. Formerly called the Advanced X-ray Astrophysics Facility, Chandra comprises three major elements: the spacecraft, the science instrument module (SIM), and the world's most powerful X-ray telescope. Chandra will allow scientists from around the world to see previously invisible black holes and high-temperature gas clouds, giving the observatory the potential to rewrite the books on the structure and evolution of our universe. Chandra is scheduled for launch July 9 aboard Space Shuttle Columbia, on mission STS-93

KSC-99pp0363

NASA Image and Video Library

1999-03-26

TRW workers in the Vertical Processing Facility check equipment after deployment of the solar panel array above them, attached to the Chandra X-ray Observatory. Formerly called the Advanced X-ray Astrophysics Facility, Chandra comprises three major elements: the spacecraft, the science instrument module (SIM), and the world's most powerful X-ray telescope. Chandra will allow scientists from around the world to see previously invisible black holes and high-temperature gas clouds, giving the observatory the potential to rewrite the books on the structure and evolution of our universe. Chandra is scheduled for launch July 9 aboard Space Shuttle Columbia, on mission STS-93

KSC-99pp0362

NASA Image and Video Library

1999-03-26

In the Vertical Processing Facility, the Chandra X-ray Observatory is observed after deployment of the solar panel array (near the bottom and to the right). Formerly called the Advanced X-ray Astrophysics Facility, Chandra comprises three major elements: the spacecraft, the science instrument module (SIM), and the world's most powerful X-ray telescope. Chandra will allow scientists from around the world to see previously invisible black holes and high-temperature gas clouds, giving the observatory the potential to rewrite the books on the structure and evolution of our universe. Chandra is scheduled for launch July 9 aboard Space Shuttle Columbia, on mission STS-93

OV-104's RMS releases Gamma Ray Observatory (GRO) during STS-37 deployment

NASA Image and Video Library

1991-04-07

Atlantis', Orbiter Vehicle (OV) 104's, remote manipulator system (RMS) releases Gamma Ray Observatory (GRO) during STS-37 deployment. Visible on the GRO as it drifts away from the RMS end effector are the four complement instruments: the Energetic Gamma Ray Experiment (bottom); Imaging Compton Telescope (COMPTEL) (center); Oriented Scintillation Spectrometer Experiment (OSSE) (top); and Burst and Transient Source Experiment (BATSE) (at four corners). GRO's solar array (SA) panels are extended and are in orbit configuration. View was taken through aft flight deck window which reflects some of the crew compartment interior.

Skylab

NASA Image and Video Library

1970-09-01

This 1970 photograph shows Skylab's Dual X-Ray Telescopes, an Apollo Telescope Mount facility. It was designed to gather solar radiation data in the x-ray region of the solar spectrum and provide information on physical processes within the solar atmosphere. In support of the two primary telescopes, auxiliary instruments provided a continuous record of the total x-ray flux in two bands. A flare detector was also provided at the control console as an aid to astronauts for monitoring solar activity. The Marshall Space Flight Center had program management responsibility for the development of Skylab hardware and experiments.

Skylab

NASA Image and Video Library

1973-01-01

This chart details Skylab's Dual X-Ray Telescopes, one of eight Apollo Telescope Mount facilities. It was designed to gather solar radiation data in the x-ray region of the solar spectrum and provide information on physical processes within the solar atmosphere. In support of the two primary telescopes, auxiliary instruments provided a continuous record of the total x-ray flux in two bands. A flare detector was also provided at the control console as an aid to astronauts for monitoring solar activity. The Marshall Space Flight Center had program management responsibility for the development of Skylab hardware and experiments.

An innovative telescope control system architecture for SST-GATE telescopes at the CTA Observatory

NASA Astrophysics Data System (ADS)

Fasola, Gilles; Mignot, Shan; Laporte, Philippe; Abchiche, Abdel; Buchholtz, Gilles; Jégouzo, Isabelle

2014-07-01

SST-GATE (Small Size Telescope - GAmma-ray Telescope Elements) is a 4-metre telescope designed as a prototype for the Small Size Telescopes (SST) of the Cherenkov Telescope Array (CTA), a major facility for the very high energy gamma-ray astronomy of the next three decades. In this 100-telescope array there will be 70 SSTs, involving a design with an industrial view aiming at long-term service, low maintenance effort and reduced costs. More than a prototype, SST-GATE is also a fully functional telescope that shall be usable by scientists and students at the Observatoire de Meudon for 30 years. The Telescope Control System (TCS) is designed to work either as an element of a large array driven by an array controller or in a stand-alone mode with a remote workstation. Hence it is built to be autonomous with versatile interfacing; as an example, pointing and tracking —the main functions of the telescope— are managed onboard, including astronomical transformations, geometrical transformations (e.g. telescope bending model) and drive control. The core hardware is a CompactRIO (cRIO) featuring a real-time operating system and an FPGA. In this paper, we present an overview of the current status of the TCS. We especially focus on three items: the pointing computation implemented in the FPGA of the cRIO —using CORDIC algorithms— since it enables an optimisation of the hardware resources; data flow management based on OPCUA with its specific implementation on the cRIO; and the use of an EtherCAT field-bus for its ability to provide real-time data exchanges with the sensors and actuators distributed throughout the telescope.

An Observatory to Enhance the Preparation of Future California Teachers

NASA Astrophysics Data System (ADS)

Connolly, L.; Lederer, S.

2004-12-01

With a major grant from the W. M. Keck Foundation, California State University, San Bernardino is establishing a state-of-the-art teaching astronomical observatory. The Observatory will be fundamental to an innovative undergraduate physics and astronomy curriculum for Physics and Liberal Studies majors and will be integrated into our General Education program. The critical need for a research and educational observatory is linked to changes in California's Science Competencies for teacher certification. Development of the Observatory will also complement a new infusion of NASA funding and equipment support for our growing astronomy education programs and the University's established Strategic Plan for excellence in education and teacher preparation. The Observatory will consist of two domed towers. One tower will house a 20" Ritchey-Chretien telescope equipped with a CCD camera in conjunction with either UBVRI broadband filters or a spectrometer for evening laboratories and student research projects. The second tower will house the university's existing 12" Schmidt-Cassegrain optical telescope coupled with a CCD camera and an array of filters. A small aperture solar telescope will be attached to the 12" for observing solar prominences while a milar filter can be attached to the 12" for sunspot viewing. We have been very fortunate to receive a challenge grant of \\600,000 from the W. M. Keck Foundation to equip the two domed towers; we continue to seek a further \\800,000 to meet our construction needs. Funding also provided by the California State University, San Bernardino.

VLA Imaging of Protoplanetary Environments

NASA Technical Reports Server (NTRS)

Wilner, David J.

2004-01-01

We summarize the major accomplishments of our program to use high angular resolution observations at millimeter wavelengths to probe the structure of protoplanetary disks in nearby regions of star formation. The primary facilities used in this work were the Very Large Array (VLA) of the National Radio Astronomy Observatories (NRAO) located in New Mexico, and the recently upgraded Australia Telescope Compact Array (ATCA), located in Australia (to access sources in the far southern sky). We used these facilities to image thermal emission from dust particles in disks at long millimeter wavelengths, where the emission is optically thin and probes the full disk volume, including the inner regions of planet formation that remain opaque at shorter wavelengths. The best resolution obtained with the VLA is comparable to the size scales of the orbits of giant planets in our Solar System (< 10 AU).

Results from an experiment that collected visible-light polarization data using unresolved imagery for classification of geosynchronous satellites

NASA Astrophysics Data System (ADS)

Speicher, Andy; Matin, Mohammad; Tippets, Roger; Chun, Francis; Strong, David

2015-05-01

In order to protect critical military and commercial space assets, the United States Space Surveillance Network must have the ability to positively identify and characterize all space objects. Unfortunately, positive identification and characterization of space objects is a manual and labor intensive process today since even large telescopes cannot provide resolved images of most space objects. The objective of this study was to collect and analyze visible-spectrum polarization data from unresolved images of geosynchronous satellites taken over various solar phase angles. Different collection geometries were used to evaluate the polarization contribution of solar arrays, thermal control materials, antennas, and the satellite bus as the solar phase angle changed. Since materials on space objects age due to the space environment, their polarization signature may change enough to allow discrimination of identical satellites launched at different times. Preliminary data suggests this optical signature may lead to positive identification or classification of each satellite by an automated process on a shorter timeline. The instrumentation used in this experiment was a United States Air Force Academy (USAFA) Department of Physics system that consists of a 20-inch Ritchey-Chrétien telescope and a dual focal plane optical train fed with a polarizing beam splitter. Following a rigorous calibration, polarization data was collected during two nights on eight geosynchronous satellites built by various manufacturers and launched several years apart. When Stokes parameters were plotted against time and solar phase angle, the data indicates that a polarization signature from unresolved images may have promise in classifying specific satellites.

The energy spectrum of ultra-high-energy cosmic rays measured by the Telescope Array FADC fluorescence detectors in monocular mode

NASA Astrophysics Data System (ADS)

Abu-Zayyad, T.; Aida, R.; Allen, M.; Anderson, R.; Azuma, R.; Barcikowski, E.; Belz, J. W.; Bergman, D. R.; Blake, S. A.; Cady, R.; Cheon, B. G.; Chiba, J.; Chikawa, M.; Cho, E. J.; Cho, W. R.; Fujii, H.; Fujii, T.; Fukuda, T.; Fukushima, M.; Hanlon, W.; Hayashi, K.; Hayashi, Y.; Hayashida, N.; Hibino, K.; Hiyama, K.; Honda, K.; Iguchi, T.; Ikeda, D.; Ikuta, K.; Inoue, N.; Ishii, T.; Ishimori, R.; Ito, H.; Ivanov, D.; Iwamoto, S.; Jui, C. C. H.; Kadota, K.; Kakimoto, F.; Kalashev, O.; Kanbe, T.; Kasahara, K.; Kawai, H.; Kawakami, S.; Kawana, S.; Kido, E.; Kim, H. B.; Kim, H. K.; Kim, J. H.; Kim, J. H.; Kitamoto, K.; Kitamura, S.; Kitamura, Y.; Kobayashi, K.; Kobayashi, Y.; Kondo, Y.; Kuramoto, K.; Kuzmin, V.; Kwon, Y. J.; Lan, J.; Lim, S. I.; Lundquist, J. P.; Machida, S.; Martens, K.; Matsuda, T.; Matsuura, T.; Matsuyama, T.; Matthews, J. N.; Myers, I.; Minamino, M.; Miyata, K.; Murano, Y.; Nagataki, S.; Nakamura, T.; Nam, S. W.; Nonaka, T.; Ogio, S.; Ogura, J.; Ohnishi, M.; Ohoka, H.; Oki, K.; Oku, D.; Okuda, T.; Ono, M.; Oshima, A.; Ozawa, S.; Park, I. H.; Pshirkov, M. S.; Rodriguez, D. C.; Roh, S. Y.; Rubtsov, G.; Ryu, D.; Sagawa, H.; Sakurai, N.; Sampson, A. L.; Scott, L. M.; Shah, P. D.; Shibata, F.; Shibata, T.; Shimodaira, H.; Shin, B. K.; Shin, J. I.; Shirahama, T.; Smith, J. D.; Sokolsky, P.; Sonley, T. J.; Springer, R. W.; Stokes, B. T.; Stratton, S. R.; Stroman, T. A.; Suzuki, S.; Takahashi, Y.; Takeda, M.; Taketa, A.; Takita, M.; Tameda, Y.; Tanaka, H.; Tanaka, K.; Tanaka, M.; Thomas, S. B.; Thomson, G. B.; Tinyakov, P.; Tkachev, I.; Tokuno, H.; Tomida, T.; Troitsky, S.; Tsunesada, Y.; Tsutsumi, K.; Tsuyuguchi, Y.; Uchihori, Y.; Udo, S.; Ukai, H.; Vasiloff, G.; Wada, Y.; Wong, T.; Yamakawa, Y.; Yamane, R.; Yamaoka, H.; Yamazaki, K.; Yang, J.; Yoneda, Y.; Yoshida, S.; Yoshii, H.; Zollinger, R.; Zundel, Z.

2013-08-01

We present a measurement of the energy spectrum of ultra-high-energy cosmic rays performed by the Telescope Array experiment using monocular observations from its two new FADC-based fluorescence detectors. After a short description of the experiment, we describe the data analysis and event reconstruction procedures. Since the aperture of the experiment must be calculated by Monte Carlo simulation, we describe this calculation and the comparisons of simulated and real data used to verify the validity of the aperture calculation. Finally, we present the energy spectrum calculated from the merged monocular data sets of the two FADC-based detectors, and also the combination of this merged spectrum with an independent, previously published monocular spectrum measurement performed by Telescope Array's third fluorescence detector [T. Abu-Zayyad et al., The energy spectrum of Telescope Array's middle drum detector and the direct comparison to the high resolution fly's eye experiment, Astroparticle Physics 39 (2012) 109-119, http://dx.doi.org/10.1016/j.astropartphys.2012.05.012, Available from: ]. This combined spectrum corroborates the recently published Telescope Array surface detector spectrum [T. Abu-Zayyad, et al., The cosmic-ray energy spectrum observed with the surface detector of the Telescope Array experiment, ApJ 768 (2013) L1, http://dx.doi.org/10.1088/2041-8205/768/1/L1, Available from: ] with independent systematic uncertainties.

The single mirror small sized telescope for the Cherenkov telescope array

NASA Astrophysics Data System (ADS)

Heller, M.; Schioppa, E., Jr.; Porcelli, A.; Pujadas, I. Troyano; Ziętara, K.; Della Volpe, D.; Montaruli, T.; Cadoux, F.; Favre, Y.; Aguilar, J. A.; Christov, A.; Prandini, E.; Rajda, P.; Rameez, M.; Bilnik, W.; Błocki, J.; Bogacz, L.; Borkowski, J.; Bulik, T.; Frankowski, A.; Grudzińska, M.; Idźkowski, B.; Jamrozy, M.; Janiak, M.; Kasperek, J.; Lalik, K.; Lyard, E.; Mach, E.; Mandat, D.; Marszałek, A.; Miranda, L. D. Medina; Michałowski, J.; Moderski, R.; Neronov, A.; Niemiec, J.; Ostrowski, M.; Paśko, P.; Pech, M.; Schovanek, P.; Seweryn, K.; Sliusar, V.; Skowron, K.; Stawarz, Ł.; Stodulska, M.; Stodulski, M.; Walter, R.; Więcek, M.; Zagdański, A.; CTA Consortium

2017-01-01

The Small Size Telescope with Single Mirror (SST-1M) is one of the proposed types of Small Size Telescopes (SST) for the Cherenkov Telescope Array (CTA). About 70 SST telescopes will be part the CTA southern array which will also include Medium Sized Telescopes (MST) in its threshold configuration. Optimized for the detection of gamma rays in the energy range from 5 TeV to 300 TeV, the SST-1M uses a Davies-Cotton optics with a 4 m dish diameter with a field of view of 9°. The Cherenkov light resulting from the interaction of the gamma-rays in the atmosphere is focused onto a 88 cm side-to-side hexagonal photo-detection plane. The latter is composed of 1296 hollow light guides coupled to large area hexagonal silicon photomultipliers (SiPM). The SiPM readout is fully digital readout as for the trigger system. The compact and lightweight design of the SST-1M camera offiers very high performance ideal for gamma-ray observation requirement. In this contribution, the concept, design, performance and status of the first telescope prototype are presented.

Potential of the McMath-Pierce 1.6-Meter Solar Telescope for Speckle Interferometry

NASA Astrophysics Data System (ADS)

Harshaw, Richard; Jones, Gregory; Wiley, Edward; Boyce, Patrick; Branston, Detrick; Rowe, David; Genet, Russell

2015-09-01

We explored the aiming and tracking accuracy of the McMath-Pierce 1.6 m solar telescope at Kitt Peak National Observatory as part of an investigation of using this telescope for speckle interferometry of close visual double stars. Several slews of various lengths looked for hysteresis in the positioning system (we found none of significance) and concluded that the 1.6 m telescope would make a useful telescope for speckle interferometry.

ATM photoheliograph. [at a solar observatory

NASA Technical Reports Server (NTRS)

Prout, R. A.

1975-01-01

The design and fabrication are presented of a 65 cm photoheliograph functional verification unit (FVU) installed in a major solar observatory. The telescope is used in a daily program of solar observation while serving as a test bed for the development of instrumentation to be included in early space shuttle launched solar telescopes. The 65 cm FVU was designed to be mechanically compatible with the ATM spar/canister and would be adaptable to a second ATM flight utilizing the existing spar/canister configuration. An image motion compensation breadboard and a space-hardened, remotely tuned H alpha filter, as well as solar telescopes of different optical configurations or increased aperture are discussed.

New Voltage and Current Thresholds Determined for Sustained Space Plasma Arcing

NASA Technical Reports Server (NTRS)

Ferguson, Dale C.; Galofaro, Joel T.; Vayner, Boris V.

2003-01-01

It has been known for many years, based partly on NASA Glenn Research Center testing, that high-voltage solar arrays arc into the space plasma environment. Solar arrays are composed of solar cells in series with each other (a string), and the strings may be connected in parallel to produce the entire solar array power. Arcs on solar arrays can damage or destroy solar cells, and in the extreme case of sustained arcing, entire solar array strings, in a flash. In the case of sustained arcing (discovered at Glenn and applied to the design and construction of solar arrays on Space Systems/Loral (SS/Loral, Palo Alto, CA) satellites, Deep-Space 1, and Terra), an arc on one solar array string can couple to an adjacent string and continue to be powered by the solar array output until a permanent electrical short is produced. In other words, sustained arcs produced by arcs into the plasma (so-called trigger arcs) may turn into disastrous sustained arcs by involving other array strings.

Fabrication and testing of 4.2m off-axis aspheric primary mirror of Daniel K. Inouye Solar Telescope

NASA Astrophysics Data System (ADS)

Oh, Chang Jin; Lowman, Andrew E.; Smith, Greg A.; Su, Peng; Huang, Run; Su, Tianquan; Kim, Daewook; Zhao, Chunyu; Zhou, Ping; Burge, James H.

2016-07-01

Daniel K. Inouye Solar Telescope (formerly known as Advanced Technology Solar Telescope) will be the largest optical solar telescope ever built to provide greatly improved image, spatial and spectral resolution and to collect sufficient light flux of Sun. To meet the requirements of the telescope the design adopted a 4m aperture off-axis parabolic primary mirror with challenging specifications of the surface quality including the surface figure, irregularity and BRDF. The mirror has been completed at the College of Optical Sciences in the University of Arizona and it meets every aspect of requirement with margin. In fact this mirror may be the smoothest large mirror ever made. This paper presents the detail fabrication process and metrology applied to the mirror from the grinding to finish, that include extremely stable hydraulic support, IR and Visible deflectometry, Interferometry and Computer Controlled fabrication process developed at the University of Arizona.

(abstract) Scaling Nominal Solar Cell Impedances for Array Design

NASA Technical Reports Server (NTRS)

Mueller, Robert L; Wallace, Matthew T.; Iles, Peter

1994-01-01

This paper discusses a task the objective of which is to characterize solar cell array AC impedance and develop scaling rules for impedance characterization of large arrays by testing single solar cells and small arrays. This effort is aimed at formulating a methodology for estimating the AC impedance of the Mars Pathfinder (MPF) cruise and lander solar arrays based upon testing single cells and small solar cell arrays and to create a basis for design of a single shunt limiter for MPF power control of flight solar arrays having very different inpedances.

High-efficiency concentration/multi-solar-cell system for orbital power generation

NASA Technical Reports Server (NTRS)

Onffroy, J. R.; Stoltzmann, D. E.; Lin, R. J. H.; Knowles, G. R.

1980-01-01

An analysis was performed to determine the economic feasibility of a concentrating spectrophotovoltaic orbital electrical power generation system. In this system dichroic beam-splitting mirrors are used to divide the solar spectrum into several wavebands. Absorption of these wavebands by solar cells with matched energy bandgaps increases the cell efficiency while decreasing the amount of heat which must be rejected. The optical concentration is performed in two stages. The first concentration stage employs a Cassegrain-type telescope, resulting in a short system length. The output from this stage is directed to compound parabolic concentrators which comprise the second stage of concentration. Ideal efficiencies for one-, two-, three-, and four-cell systems were calculated under 1000 sun, AMO conditions, and optimum energy bands were determined. Realistic efficiencies were calculated for various combinations of Si, GaAs, Ge and GaP. Efficiencies of 32 to 33 percent were obtained with the multicell systems. The optimum system consists of an f/3.5 optical system, a beam splitter to divide the spectrum at 0.9 microns, and two solar cell arrays, GaAs and Si.

Optical Path Difference Fluctations at the CHARA Interferometric Array

NASA Astrophysics Data System (ADS)

Merand, A.; ten Brummelaar, T. A.; McAlister, H. A.; Ridgway, S. T.; Sturmann, J.; Sturmann, L.; Turner, N. H.; Bagnuolo, W. G.; Hrynevych, M.; Shure, M. A.

2001-05-01

Commissioning observations at the CHARA Array have been carried out with the two south telescopes, with a telescope separation of 34 meters. Due to the size of the array (>340 meters across) and the optical delay geometry, the beams travel horizontal distances of approximately 200 meters, with a number of reflections in the telescope coude area and the optical delay and beam combination areas. Stellar and laboratory observations have been analyzed to determine the variations of the optical path, as revealed by shifts in the interference pattern. The power spectra of the OPD variations are diagnostic of the atmospheric turbulence characteristics, and of any internal vibrations in the laboratory. Results of the OPD analysis will be compared to similar studies at other interferometric facilities. The CHARA Array, a six-telescope O/IR interferometric array operated by Georgia State University on Mt. Wilson, Calfornia, was funded by the National Science Foundation, the W.M. Keck Foundation, the David and Lucile Packard Foundation, and Georgia State University.

High Resolution Observations of Solar Quiescent Prominences with the Hinode Solar Optical Telescope: an Open Challenge to 21st Century Ground-based Solar Telescopes (Invited)

NASA Astrophysics Data System (ADS)

Berger, T. E.

2009-12-01

The Solar Optical Telescope (SOT) on the Japanese Hinode satellite is a 0.5-meter diameter Gregorian solar telescope in a 600 km Sun-synchronous orbit. The telescope achieves diffraction-limited imaging with no atmospheric seeing in a wavelength range from 380 nm to 660 nm. Using both the Broadband Filter Imager (BFI) Ca II H-line channel at 389.6 nm and the tunable Narrowband Filter Imager (NFI) H-alpha channel at 656.3 nm we have observed many quiescent solar prominences since the satellite launch in September 2006. The excellent optical quality and low scattering of the SOT telescope combined with the lack of atmospheric scattering and seeing enables us to capture multi-hour diffraction-limited movies of quiescent prominences above the limb that achieve 200 km spatial resolution and 15--30 second temporal resolution. These SOT observations have led to the discovery of new flows in the solar outer atmosphere in the form of buoyant small-scale (2--6 Mm) plumes and large-scale (10--50 Mm) "bubbles" or arches that originate below quiescent prominences and rise with speeds of 10--30 km/sec to heights of 10--30+ Mm above the solar limb. In this talk we review the kinematic properties of these new flows in combination with the long-observed filamentary downflows to show that quisecent prominences are not magnetostatic structures "suspended against gravity" but are rather entirely dynamic structures in which mass is continually drained in the downflows while being resupplied largely by condensation from the coronal cavity above and episodic buoyant flows from below. The Hinode/SOT instrument has definitively shown the value of flying high-resolution visible-light solar telescopes in space by acheiving in its first six months what had been a long-standing goal of ground-based solar prominence research for the past 50 years. However many key quiescent prominence characteristics cannot be measured by the limited instrumentation on the Hinode satellite. Primary among these is vector magnetic field in prominences at high spatial and temporal resolution and the thermodynamic and magnetic characteristics of the new plume and bubble flows. It is hoped that the new generation of adaptive-optics ground-based telescopes such as the 1.6-m NST can make progress in these areas while we await the next solar space telescope missions.

Mass motion in upper solar chromosphere detected from solar eclipse observation

NASA Astrophysics Data System (ADS)

Li, Zhi; Qu, Zhongquan; Yan, Xiaoli; Dun, Guangtao; Chang, Liang

2016-05-01

The eclipse-observed emission lines formed in the upper solar atmosphere can be used to diagnose the atmosphere dynamics which provides an insight to the energy balance of the outer atmosphere. In this paper, we analyze the spectra formed in the upper chromospheric region by a new instrument called Fiber Arrayed Solar Optic Telescope (FASOT) around the Gabon total solar eclipse on November 3, 2013. The double Gaussian fits of the observed profiles are adopted to show enhanced emission in line wings, while red-blue (RB) asymmetry analysis informs that the cool line (about 104 K) profiles can be decomposed into two components and the secondary component is revealed to have a relative velocity of about 16-45 km s^{-1}. The other profiles can be reproduced approximately with single Gaussian fits. From these fittings, it is found that the matter in the upper solar chromosphere is highly dynamic. The motion component along the line-of-sight has a pattern asymmetric about the local solar radius. Most materials undergo significant red shift motions while a little matter show blue shift. Despite the discrepancy of the motion in different lines, we find that the width and the Doppler shifts both are function of the wavelength. These results may help us to understand the complex mass cycle between chromosphere and corona.

Skylab

NASA Image and Video Library

1974-01-01

This Skylab-4 mission onboard photograph shows Astronaut Ed Gibson at the complex control and display console for the Apollo Telescope Mount solar telescopes located in the Skylab Multiple Docking Adapter. Astronauts watched the Sun, and photographed and recorded the solar activities, such as the birth of a solar flare.

Imaging phased telescope array study

NASA Technical Reports Server (NTRS)

Harvey, James E.

1989-01-01

The problems encountered in obtaining a wide field-of-view with large, space-based direct imaging phased telescope arrays were considered. After defining some of the critical systems issues, previous relevant work in the literature was reviewed and summarized. An extensive list was made of potential error sources and the error sources were categorized in the form of an error budget tree including optical design errors, optical fabrication errors, assembly and alignment errors, and environmental errors. After choosing a top level image quality requirment as a goal, a preliminary tops-down error budget allocation was performed; then, based upon engineering experience, detailed analysis, or data from the literature, a bottoms-up error budget reallocation was performed in an attempt to achieve an equitable distribution of difficulty in satisfying the various allocations. This exercise provided a realistic allocation for residual off-axis optical design errors in the presence of state-of-the-art optical fabrication and alignment errors. Three different computational techniques were developed for computing the image degradation of phased telescope arrays due to aberrations of the individual telescopes. Parametric studies and sensitivity analyses were then performed for a variety of subaperture configurations and telescope design parameters in an attempt to determine how the off-axis performance of a phased telescope array varies as the telescopes are scaled up in size. The Air Force Weapons Laboratory (AFWL) multipurpose telescope testbed (MMTT) configuration was analyzed in detail with regard to image degradation due to field curvature and distortion of the individual telescopes as they are scaled up in size.

TESS Spacecraft Solar Panel Array Deployment Testing

NASA Image and Video Library

2018-02-21

Inside the Payload Hazardous Servicing Facility at the NASA's Kennedy Space Center in Florida, both solar panels are deployed on the agency's Transiting Exoplanet Survey Satellite (TESS). The satellite is scheduled to launch atop a SpaceX Falcon 9 rocket from Space Launch Complex 40 at Cape Canaveral Air Force Station. TESS is the next step in NASA's search for planets outside our solar system, known as exoplanets. TESS is a NASA Astrophysics Explorer mission led and operated by MIT in Cambridge, Massachusetts, and managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Dr. George Ricker of MIT’s Kavli Institute for Astrophysics and Space Research serves as principal investigator for the mission. Additional partners include Orbital ATK, NASA’s Ames Research Center, the Harvard-Smithsonian Center for Astrophysics and the Space Telescope Science Institute. More than a dozen universities, research institutes and observatories worldwide are participants in the mission. NASA’s Launch Services Program is responsible for launch management.

TESS Spacecraft Solar Panel Array Deployment Testing

NASA Image and Video Library

2018-02-21

Inside the Payload Hazardous Servicing Facility at the NASA's Kennedy Space Center in Florida, the first of two solar panels is being deployed on the agency's Transiting Exoplanet Survey Satellite (TESS). The satellite is scheduled to launch atop a SpaceX Falcon 9 rocket from Space Launch Complex 40 at Cape Canaveral Air Force Station. TESS is the next step in NASA's search for planets outside our solar system, known as exoplanets. TESS is a NASA Astrophysics Explorer mission led and operated by MIT in Cambridge, Massachusetts, and managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Dr. George Ricker of MIT’s Kavli Institute for Astrophysics and Space Research serves as principal investigator for the mission. Additional partners include Orbital ATK, NASA’s Ames Research Center, the Harvard-Smithsonian Center for Astrophysics and the Space Telescope Science Institute. More than a dozen universities, research institutes and observatories worldwide are participants in the mission. NASA’s Launch Services Program is responsible for launch management.

TESS Spacecraft Solar Panel Array Deployment Testing

NASA Image and Video Library

2018-02-21

Preparations are underway for solar panel deployment on NASA's Transiting Exoplanet Survey Satellite (TESS) inside the Payload Hazardous Servicing Facility at the agency's Kennedy Space Center in Florida. TESS is scheduled to launch atop a SpaceX Falcon 9 rocket from Space Launch Complex 40 at Cape Canaveral Air Force Station. The satellite is the next step in NASA's search for planets outside our solar system, known as exoplanets. TESS is a NASA Astrophysics Explorer mission led and operated by MIT in Cambridge, Massachusetts, and managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Dr. George Ricker of MIT’s Kavli Institute for Astrophysics and Space Research serves as principal investigator for the mission. Additional partners include Orbital ATK, NASA’s Ames Research Center, the Harvard-Smithsonian Center for Astrophysics and the Space Telescope Science Institute. More than a dozen universities, research institutes and observatories worldwide are participants in the mission. NASA’s Launch Services Program is responsible for launch management.

The Advanced Gamma-ray Imaging System (AGIS): Real Time Stereoscopic Array Trigger

NASA Astrophysics Data System (ADS)

Byrum, K.; Anderson, J.; Buckley, J.; Cundiff, T.; Dawson, J.; Drake, G.; Duke, C.; Haberichter, B.; Krawzcynski, H.; Krennrich, F.; Madhavan, A.; Schroedter, M.; Smith, A.

2009-05-01

Future large arrays of Imaging Atmospheric Cherenkov telescopes (IACTs) such as AGIS and CTA are conceived to comprise of 50 - 100 individual telescopes each having a camera with 10**3 to 10**4 pixels. To maximize the capabilities of such IACT arrays with a low energy threshold, a wide field of view and a low background rate, a sophisticated array trigger is required. We describe the design of a stereoscopic array trigger that calculates image parameters and then correlates them across a subset of telescopes. Fast Field Programmable Gate Array technology allows to use lookup tables at the array trigger level to form a real-time pattern recognition trigger tht capitalizes on the multiple view points of the shower at different shower core distances. A proof of principle system is currently under construction. It is based on 400 MHz FPGAs and the goal is for camera trigger rates of up to 10 MHz and a tunable cosmic-ray background suppression at the array level.

Solar cell array design handbook - The principles and technology of photovoltaic energy conversion

NASA Technical Reports Server (NTRS)

Rauschenbach, H. S.

1980-01-01

Photovoltaic solar cell array design and technology for ground-based and space applications are discussed from the user's point of view. Solar array systems are described, with attention given to array concepts, historical development, applications and performance, and the analysis of array characteristics, circuits, components, performance and reliability is examined. Aspects of solar cell array design considered include the design process, photovoltaic system and detailed array design, and the design of array thermal, radiation shielding and electromagnetic components. Attention is then given to the characteristics and design of the separate components of solar arrays, including the solar cells, optical elements and mechanical elements, and the fabrication, testing, environmental conditions and effects and material properties of arrays and their components are discussed.

Current status of the expanded GRAPES collaboration experiment at Ooty in India

NASA Astrophysics Data System (ADS)

Gupta, S.K.; Anita, H.M.; Iyer, A.; Jagadeesan, P.; Jain, A.; Karthikeyan, S.; Manoharan, P.K.; Mohanty, P.K.; Nayak, P.K.; Rao, B.S.; Ravindran, K.C.; Tanaka, H.; Tonwar, S.C.; Ogio, S.; Okuda, T.; Oshima, A.; Shimizu, N.; Yoshikoshi, T.; Badruddin; Hasan, R.; Ahmad, Shakeel; Mishra, A.P.; Shrivastava, P.K.; Koul, R.; Shah, G.N.; Mir, T.A.; Mufti, S.; Raha, S.; Ghosh, S.; Joarder, P.; Saha, S.; Boruah, K.; Datta, P.; Boruah, P.K.; Baruah, A.G.; Baishya, R.; Saikia, J.; Banerjee, D.; Subramanian, P.; Bhadra, A.; Kumar, S.; Agarwal, R.; Dubey, S.K.; Bhattacharjee, P.

GRAPES-3 experiment employs a high-density array of scintillators and a large area tracking muon telescope. The GRAPES collaboration is being expanded with addition of several major facilities. These include a Cerenkov telescope and low frequency dipole array for the measurement of shower energy. Addition of several modules of muon telescopes to cover a larger area, expansion of the scintillator array with greater separation between detectors. Installation of a neutron monitor is also planned. The current status of the experiment would be summarized.

The Atacama Cosmology Telescope: The Receiver and Instrumentation

NASA Technical Reports Server (NTRS)

Swetz, D. S.; Ade, P. A. R.; Amiri, M.; Appel, J. W.; Burger, B.; Devlin, M. J.; Dicker, S. R.; Doriese, W. B.; Essinger-Hileman, T.; Fisher, R. P.;

NASA Marshall Space Flight Center solar observatory report, January - June 1991

NASA Technical Reports Server (NTRS)

Smith, James E.

1991-01-01

Given here is a summary of the solar vector magnetic field, H-alpha, and white-light observations made at the NASA/Marshall Space Flight Center (MSFC) Solar Observatory during its daily periods of operation. The MSFC Solar Observatory facilities consist of the Solar Magnetograph, an f/13, 30-cm Cassegrain system with a 3.5-cm image of the Sun, housed on top of a 12.8-meter tower; a 12.5-cm Razdow H-alpha telescope housed at the base of the tower; an 18-cm Questar telescope with a full aperture white-light filter mounted at the base of the tower; a 30-cm Cassegrain telescope located in a second metal dome; and a 16.5-cm H-alpha telescope mounted on side of the Solar Vector Magnetograph. A concrete block building provides office space, a darkroom for developing film and performing optical testing, a workshop, video displays, and a computer facility for data reduction.

NASA Marshall Space Flight Center Solar Observatory report, July - December 1991

NASA Technical Reports Server (NTRS)

Smith, James E.

1992-01-01

A summary is given of the solar vector magnetic field, H-alpha, and white light observations made at the NASA/Marshall Space Flight Center (MSFC) Solar Observatory during its daily periods of observation. The MSFC Solar Observatory facilities consist of the Solar Magnetograph, an f-13, 30 cm Cassegrain system with a 3.5 cm image of the Sun housed on top of a 12.8 meter tower, a 12.5 cm Razdow H-alpha telescope housed at the base of the tower, an 18 cm Questar telescope with a full aperture white-light filter mounted at the base of the tower, a 30 cm Cassegrain telescope located in a second metal dome, and a 16.5 cm H-alpha telescope mounted on the side of the Solar Vector Magnetograph. A concrete block building provides office space, a darkroom for developing film and performing optical testing, a workshop, video displays, and a computer facility for data reduction.

Coating Processes Boost Performance of Solar Cells

NASA Technical Reports Server (NTRS)

2012-01-01

NASA currently has spacecraft orbiting Mercury (MESSENGER), imaging the asteroid Vesta (Dawn), roaming the red plains of Mars (the Opportunity rover), and providing a laboratory for humans to advance scientific research in space (the International Space Station, or ISS). The heart of the technology that powers those missions and many others can be held in the palm of your hand - the solar cell. Solar, or photovoltaic (PV), cells are what make up the panels and arrays that draw on the Sun s light to generate electricity for everything from the Hubble Space Telescope s imaging equipment to the life support systems for the ISS. To enable NASA spacecraft to utilize the Sun s energy for exploring destinations as distant as Jupiter, the Agency has invested significant research into improving solar cell design and efficiency. Glenn Research Center has been a national leader in advancing PV technology. The Center s Photovoltaic and Power Technologies Branch has conducted numerous experiments aimed at developing lighter, more efficient solar cells that are less expensive to manufacture. Initiatives like the Forward Technology Solar Cell Experiments I and II in which PV cells developed by NASA and private industry were mounted outside the ISS have tested how various solar technologies perform in the harsh conditions of space. While NASA seeks to improve solar cells for space applications, the results are returning to Earth to benefit the solar energy industry.

The Cherenkov Telescope Array For Very High-Energy Astrophysics

NASA Astrophysics Data System (ADS)

Kaaret, Philip

2015-08-01

The field of very high energy (VHE) astrophysics had been revolutionized by the results from ground-based gamma-ray telescopes, including the current imaging atmospheric Cherenkov telescope (IACT) arrays: HESS, MAGIC and VERITAS. A worldwide consortium of scientists from 29 countries has formed to propose the Cherenkov Telescope Array (CTA) that will capitalize on the power of this technique to greatly expand the scientific reach of ground-based gamma-ray telescopes. CTA science will include key topics such as the origin of cosmic rays and cosmic particle acceleration, understanding extreme environments in regions close to neutron stars and black holes, and exploring physics frontiers through, e.g., the search for WIMP dark matter, axion-like particles and Lorentz invariance violation. CTA is envisioned to consist of two large arrays of Cherenkov telescopes, one in the southern hemisphere and one in the north. Each array will contain telescopes of different sizes to provide a balance between cost and array performance over an energy range from below 100 GeV to above 100 TeV. Compared to the existing IACT arrays, CTA will have substantially better angular resolution and energy resolution, will cover a much wider energy range, and will have up to an order of magnitude better sensitivity. CTA will also be operated as an open observatory and high-level CTA data will be placed into the public domain; these aspects will enable broad participation in CTA science from the worldwide scientific community to fully capitalize on CTA's potential. This talk will: 1) review the scientific motivation and capabilities of CTA, 2) provide an overview of the technical design and the status of prototype development, and 3) summarize the current status of the project in terms of its proposed organization and timeline. The plans for access to CTA data and opportunities to propose for CTA observing time will be highlighed.Presented on behalf of the CTA Consortium.

Development of a solar-powered infrared injection laser microminiature transmitting system

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

Falter, D.D.; Alley, G.T.; Falter, K.G.

1989-01-01

A solar-powered infrared microminiature transmitting system is being developed to provide scientists with a tool to continuously track and study Africanized bees. Present tracking methods have limited ranges and lack the capability of continuously tracking individual insects. Preliminary field tests of a stationary prototypic transmitter have demonstrated a range of 1.1 km. The basic design consists of an array of nine 1-mm{sup 2} solar cells, which collect energy for storage in a 1.0-{mu}F tantalum chip capacitor. When the capacitor has been charged to a sufficient level, the circuitry that monitors the capacitor voltage level wakes up'' and fires a 5-{mu}smore » pulse through an 840-nm GaAlAs injection laser diode. The process is then repeated, making the signal frequency (which ranges from 50 to 300 Hz) dependent on solar luminance. The solar cells, capacitor, and laser diode are mounted in hybrid microcircuit fashion directly on the silicon substrate containing the CMOS control and driver circuitry. The transmitter measures {approximately}4 {times} 6 mm and weighs {approximately}65 mg. The receiving system is based on an 8-in. telescope and a Si PIN diode detector. 8 refs., 10 figs.« less

The Space-Age Legacy of Telescope Designer George A. Carroll

NASA Astrophysics Data System (ADS)

Briggs, John W.

2013-01-01

Remembered particularly as a founding member of Stony Ridge Observatory near Mount Wilson, George A. Carroll (1902-1987) was legendary in the Southern California telescope making community. In Texas at the age of sixteen, Carroll built and flew his own aircraft, becoming one of the youngest aviators in the country. He eventually became an employee of Lockheed's "Skunk Works" in Burbank. His earliest known commercial telescopes were high-end amateur instruments built by R. R. Cook. As described in a brochure describing his later telescope work, he had "experience in so many branches of technology that it is unbelievable." By the time Carroll's designs were built by Thomas Tool & Die in Sun Valley, his telescopes were well known in the solar community and in use at National Solar Observatory, Caltech, and at many other domestic and international research institutions. Among the most remarkable were large solar spars for Lockheed Solar Observatory in California and Ottawa River Solar Observatory in Canada. His instrumentation also equipped educational facilities including observatories at UCLA, Westmont College, Pasadena City College, Bevard Community College, and many others. A Carroll telescope boasting a particularly distinguished educational history was a small astrograph built in 1953 for Professor George Moyen of Hollywood and subsequently used for the long-running Summer Science Program in Ojai, California. Later solar instruments built by Carson Instruments were closely derivative of Carroll designs.

Monte Carlo performance studies for the site selection of the Cherenkov Telescope Array

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

Hassan, T.; Arrabito, L.; Bernlöhr, K.

The Cherenkov Telescope Array (CTA) represents the next generation of ground-based instruments for very-high-energy (VHE) gamma-ray astronomy, aimed at improving on the sensitivity of current-generation experiments by an order of magnitude and providing coverage over four decades of energy. The current CTA design consists of two arrays of tens of imaging atmospheric Cherenkov Telescopes, comprising Small, Medium and Large-Sized Telescopes, with one array located in each of the Northern and Southern Hemispheres. To study the effect of the site choice on the overall CTA performance and support the site evaluation process, detailed Monte Carlo simulations have been performed. These resultsmore » show the impact of different site-related attributes such as altitude, night-sky background and local geomagnetic field on CTA performance for the observation of VHE gamma rays.« less

Monte Carlo performance studies for the site selection of the Cherenkov Telescope Array

DOE PAGES

Hassan, T.; Arrabito, L.; Bernlöhr, K.; ...

2017-05-03

The Cherenkov Telescope Array (CTA) represents the next generation of ground-based instruments for very-high-energy (VHE) gamma-ray astronomy, aimed at improving on the sensitivity of current-generation experiments by an order of magnitude and providing coverage over four decades of energy. The current CTA design consists of two arrays of tens of imaging atmospheric Cherenkov Telescopes, comprising Small, Medium and Large-Sized Telescopes, with one array located in each of the Northern and Southern Hemispheres. To study the effect of the site choice on the overall CTA performance and support the site evaluation process, detailed Monte Carlo simulations have been performed. These resultsmore » show the impact of different site-related attributes such as altitude, night-sky background and local geomagnetic field on CTA performance for the observation of VHE gamma rays.« less

The optical very large array and its moon-based version

NASA Technical Reports Server (NTRS)

Labeyrie, Antoine

1992-01-01

An Optical Very Large Array (OVLA) is currently in early prototyping stages for ground-based sites, such as Mauna Kea and perhaps the VLT site in Chile. Its concept is also suited for a moon-based interferometer. With a ring of bi-dimensionally mobile telescopes, there is maximal flexibility in the aperture pattern, and no need for delay lines. A circular configuration of many free-flying telescopes, TRIO, is also considered for space interferometers. Finally, the principle of gaseous mirrors may become applicable for moon-based optical arrays. Fifteen years after the first coherent linkage of two optical telescopes, the design of an ambitious imaging array, the OVLA, is now well advanced. Two 1.5 m telescopes have been built and now provide astronomical results. Elements of the OVLA are under construction. Although primarily conceived for ground-based sites, the OVLA structure appears to meet the essential requirements for operation on the Moon.

Simulating a Measurement of the 2nd Knee in the Cosmic Ray Spectrum with an Atmospheric Fluorescence Telescope Tower Array

PubMed Central

Liu, Jiali; Yang, Qunyu; Bai, Yunxiang; Cao, Zhen

2014-01-01

A fluorescence telescope tower array has been designed to measure cosmic rays in the energy range of 1017–1018 eV. A full Monte Carlo simulation, including air shower production, light generation and propagation, detector response, electronics, and trigger system, has been developed for that purpose. Using such a simulation tool, the detector configuration, which includes one main tower array and two side-trigger arrays, 24 telescopes in total, has been optimized. The aperture and the event rate have been estimated. Furthermore, the performance of the X max⁡ technique in measuring composition has also been studied. PMID:24737964

Pupil geometry and pupil re-imaging in telescope arrays

NASA Technical Reports Server (NTRS)

Traub, Wesley A.

1990-01-01

This paper considers the issues of lateral and longitudinal pupil geometry in ground-based telescope arrays, such as IOTA. In particular, it is considered whether or not pupil re-imaging is required before beam combination. By considering the paths of rays through the system, an expression is derived for the optical path errors in the combined wavefront as a function of array dimensions, telescope magnification factor, viewing angle, and field-of-view. By examining this expression for the two cases of pupil-plane and image-plane combination, operational limits can be found for any array. As a particular example, it is shown that for IOTA no pupil re-imaging optics will be needed.

Using frequency response functions to manage image degradation from equipment vibration in the Daniel K. Inouye Solar Telescope

NASA Astrophysics Data System (ADS)

McBride, William R.; McBride, Daniel R.

2016-08-01

The Daniel K Inouye Solar Telescope (DKIST) will be the largest solar telescope in the world, providing a significant increase in the resolution of solar data available to the scientific community. Vibration mitigation is critical in long focal-length telescopes such as the Inouye Solar Telescope, especially when adaptive optics are employed to correct for atmospheric seeing. For this reason, a vibration error budget has been implemented. Initially, the FRFs for the various mounting points of ancillary equipment were estimated using the finite element analysis (FEA) of the telescope structures. FEA analysis is well documented and understood; the focus of this paper is on the methods involved in estimating a set of experimental (measured) transfer functions of the as-built telescope structure for the purpose of vibration management. Techniques to measure low-frequency single-input-single-output (SISO) frequency response functions (FRF) between vibration source locations and image motion on the focal plane are described. The measurement equipment includes an instrumented inertial-mass shaker capable of operation down to 4 Hz along with seismic accelerometers. The measurement of vibration at frequencies below 10 Hz with good signal-to-noise ratio (SNR) requires several noise reduction techniques including high-performance windows, noise-averaging, tracking filters, and spectral estimation. These signal-processing techniques are described in detail.

CHAIN-project and installation of the flare monitoring telescopes in developing countries

NASA Astrophysics Data System (ADS)

Ueno, Satoru; Shibata, Kazunari; Kimura, Goichi; Nakatani, Yoshikazu; Kitai, Reizaburo; Nagata, Shin'ichi

2007-12-01

The Flare Monitoring Telescope (FMT) was constructed in 1992 at the Hida Observatory in Japan to investigate the long-term variation of solar activity and explosive events, as a project of the international coordinated observations programme (STEP). The FMT consists of five solar imaging telescopes and one guide telescope. The five telescopes simultaneously observe the full-disk Sun at different wavelengths around H-alpha absorption line or in different modes. Therefore, the FMT can measure the three-dimensional velocity field of moving structures on the full solar disk without the atmospheric seeing effect. The science target of the FMT is to monitor solar flares and erupting filaments continuously all over the solar disk and as many events as possible and to investigate the relationship between such phenomena and space weather. Now we are planning to start a new worldwide project called as ``Continuous H-alpha Imaging Network (CHAIN)-project''. As part of this project, we are examining the possibility of installing telescopes similar to the FMT in developing countries with cooperative help by the United Nations. We have selected Peru as the candidate country where the first oversea FMT will be installed, and are beginning to study the natural environment, the seeing conditions, the proper design of the telescope for Peru and the training and education programme of operating staff, etc.

The readout and control system of the mid-size telescope prototype of the Cherenkov Telescope Array

NASA Astrophysics Data System (ADS)

Oya, I.; Anguner, O.; Behera, B.; Birsin, E.; Fuessling, M.; Melkumyan, D.; Schmidt, T.; Schwanke, U.; Sternberger, R.; Wegner, P.; Wiesand, S.; Cta Consortium,the

2014-06-01

The Cherenkov Telescope Array (CTA) is one of the major ground-based astronomy projects being pursued and will be the largest facility for ground-based y-ray observations ever built. CTA will consist of two arrays: one in the Northern hemisphere composed of about 20 telescopes, and the other one in the Southern hemisphere composed of about 100 telescopes, both arrays containing telescopes of different type and size. A prototype for the Mid-Size Telescope (MST) with a diameter of 12 m has been installed in Berlin and is currently being commissioned. This prototype is composed of a mechanical structure, a drive system and mirror facets mounted with powered actuators to enable active control. Five Charge-Coupled Device (CCD) cameras, and a wide set of sensors allow the evaluation of the performance of the instrument. The design of the control software is following concepts and tools under evaluation within the CTA consortium in order to provide a realistic test-bed for the middleware: 1) The readout and control system for the MST prototype is implemented with the Atacama Large Millimeter/submillimeter Array (ALMA) Common Software (ACS) distributed control middleware; 2) the OPen Connectivity-Unified Architecture (OPC UA) is used for hardware access; 3) the document oriented MongoDB database is used for an efficient storage of CCD images, logging and alarm information: and 4) MySQL and MongoDB databases are used for archiving the slow control monitoring data and for storing the operation configuration parameters. In this contribution, the details of the implementation of the control system for the MST prototype telescope are described.

Mount control system of the ASTRI SST-2M prototype for the Cherenkov Telescope Array

NASA Astrophysics Data System (ADS)

Antolini, Elisa; Tosti, Gino; Tanci, Claudio; Bagaglia, Marco; Canestrari, Rodolfo; Cascone, Enrico; Gambini, Giorgio; Nucciarelli, Giuliano; Pareschi, Giovanni; Scuderi, Salvo; Stringhetti, Luca; Busatta, Andrea; Giacomel, Stefano; Marchiori, Gianpietro; Manfrin, Cristiana; Marcuzzi, Enrico; Di Michele, Daniele; Grigolon, Carlo; Guarise, Paolo

2016-08-01

The ASTRI SST-2M telescope is an end-to-end prototype proposed for the Small Size class of Telescopes (SST) of the future Cherenkov Telescope Array (CTA). The prototype is installed in Italy at the INAF observing station located at Serra La Nave on Mount Etna (Sicily) and it was inaugurated in September 2014. This paper presents the software and hardware architecture and development of the system dedicated to the control of the mount, health, safety and monitoring systems of the ASTRI SST-2M telescope prototype. The mount control system installed on the ASTRI SST-2M telescope prototype makes use of standard and widely deployed industrial hardware and software. State of the art of the control and automation industries was selected in order to fulfill the mount related functional and safety requirements with assembly compactness, high reliability, and reduced maintenance. The software package was implemented with the Beckhoff TwinCAT version 3 environment for the software Programmable Logical Controller (PLC), while the control electronics have been chosen in order to maximize the homogeneity and the real time performance of the system. The integration with the high level controller (Telescope Control System) has been carried out by choosing the open platform communications Unified Architecture (UA) protocol, supporting rich data model while offering compatibility with the PLC platform. In this contribution we show how the ASTRI approach for the design and implementation of the mount control system has made the ASTRI SST-2M prototype a standalone intelligent machine, able to fulfill requirements and easy to be integrated in an array configuration such as the future ASTRI mini-array proposed to be installed at the southern site of the Cherenkov Telescope Array (CTA).

First solar radio spectrometer deployed in Scotland, UK

NASA Astrophysics Data System (ADS)

Monstein, Christian

2012-10-01

A new Callisto solar radio spectrometer system has recently been installed and set into operation at Acre Road Observatory, a facility of University of Glasgow, Scotland UK. There has been an Observatory associated with Glasgow University since 1757, and they presently occupy two different sites. The main observatory ('Acre Road') is close to the Garscube Estate on the outskirts of the city of Glasgow. The outstation ('Cochno', housing the big 20 inch Grubb Parsons telescope) is located farther out at a darker site in the Kilpatrick Hills. The Acre Road Observatory comprises teaching and research labs, a workshop, the main dome housing the 16 inch Meade, the solar dome, presently housing the 12 inch Meade, a transit house containing the transit telescope, a 3m HI radio telescope and a 408 MHz pulsar telescope. They also have 10 and 8 inch Meade telescopes and several 5 inch Celestron instruments. There is a small planetarium beneath the solar dome. The new Callisto instrument is mainly foreseen for scientific solar burst observations as well as for student projects and for 'bad-weather' outreach activities.

Skylab

NASA Image and Video Library

1973-01-01

This chart describes the Hydrogen-Alpha (H-Alpha) #2 Telescope, one of eight major solar study facilities on the Skylab Apollo Telescope Mount (ATM). There were two H-Alpha telescopes on the ATM that were used primarily to point the ATM and keep a continuous photographic record during solar observation periods. Both telescopes gave the Skylab astronauts a real-time picture of the Sun in the red light of the H-Alpha spectrum through a closed-circuit television. The H-Alpha #1 telescope provided simultaneous photographic and ultraviolet (UV) pictures, while the #2 telescope operated only in the TV mode. The Marshall Space Flight Center was responsible for development of the H-Alpha Telescopes.

Skylab

NASA Image and Video Library

1973-01-01

This chart describes the Hydrogen-Alpha (H-Alpha) #1 Telescope, one of eight major solar study facilities on the Skylab Apollo Telescope Mount (ATM). There were two H-Alpha telescopes on the ATM that were used primarily to point the ATM and keep a continuous photographic record during the solar observation periods. Both telescopes gave the Skylab astronauts a real-time picture of the Sun in the red light of the H-Alpha spectrum through a closed-circuit television. The H-Alpha #1 Telescope provided simultaneous photographic and ultraviolet (UV) pictures, while the #2 Telescope operated only in the TV mode. The Marshall Space Flight Center was responsible for development of the H-Alpha Telescopes.

VLBA Detects Earth's Motion Around the Milky Way's Center

NASA Astrophysics Data System (ADS)

1999-06-01

It takes our Solar System more than 200 million years to orbit the center of the Milky Way Galaxy, 26,000 light-years away. Despite that tremendously long time span, astronomers using the National Science Foundation's (NSF) powerful Very Long Baseline Array (VLBA) radio telescope have shown they can detect this orbital motion in ten days! In addition, they have made a new and more accurate determination of just how long it takes us to circle our Galaxy -- 226 million years. "Not only is this a tremendous technical achievement, but it also has allowed us to greatly strengthen the scientific case for a supermassive black hole at the Galaxy's center -- definitely ruling out a multiple-star system," said Mark Reid of the Harvard-Smithsonian Center for Astrophysics. Reid, along with Anthony Readhead and Rene Vermuelen of Caltech and Robert Treuhaft of the Jet Propulsion Laboratory, announced their discovery at the American Astronomical Society's meeting in Chicago. The scientists used the continent-wide VLBA, part of the NSF's National Radio Astronomy Observatory (NRAO), to observe a radio-wave-emitting object called Sagittarius A* (pronounced "A-star"), that has been thought to mark the exact center of the Milky Way since its discovery more than two decades ago. They were able to measure its position on the sky within nearly one ten-thousandth of a second of arc -- a precision 600,000 times greater than that of the human eye and more than 500 times greater than that of the Hubble Space Telescope. With this precision, the astronomers were able to detect the slight apparent shift in position of Sagittarius A* compared to the positions of much more-distant quasars behind it. That apparent shift was caused by the motion of the Solar System around the Galaxy's center. "From these measurements, we estimate that we are moving at about 135 miles per second in our orbit around the center of the Milky Way," Reid said. "Even though it takes more than 200 million years for us to complete an orbit of the Galaxy's center, we can detect this motion in ten days' observing with the VLBA!" The observations allowed the scientists to calculate a more accurate figure for how long it takes the Solar System to orbit the Galaxy's center. "Our new figure of 226 million years is accurate to within six percent," Reid said. "The measurements we made with the VLBA place Sagittarius A* very close to, and most likely at, the exact (dynamical) center of our Galaxy, just as we expected," Reid said. "Right now, the new data also indicate that the minimum mass for this object is about 1,000 times the mass of the Sun. This rules out a multiple-star system and strengthens the idea that this object, much smaller than our own Solar System, contains a black hole about 2.6 million times more massive than the Sun," Reid added. "We plan future observations that will increase the accuracy of our measurements even further, and, we suspect, raise the minimum mass for this object by as much as 100 times," Reid said. The Milky Way's center, a complex region containing not only Sagittarius A* but also numerous supernova remnants and magnetic features, is obscured from optical telescopes by dust. Sagittarius A* was discovered in 1974 by astronomers using radio telescopes at the NRAO facility in Green Bank, WV. The NRAO's Very Large Array (VLA) and the VLBA both have been used for numerous studies of the Galactic Center region. The VLBA is a system of ten radio-telescope antennas, each 25 meters (82 feet) in diameter, stretching some 5,000 miles from Mauna Kea in Hawaii to St. Croix in the U.S. Virgin Islands. Operated from NRAO's Array Operations Center in Socorro, NM, the VLBA offers astronomers the greatest resolving power, or ability to see fine detail, of any telescope currently operational. The NRAO is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

The Miniature X-ray Solar Spectrometer (MinXSS) CubeSats: instrument capabilities and early science analysis on the quiet Sun, active regions, and flares.

NASA Astrophysics Data System (ADS)

Moore, Christopher S.; Woods, Tom; Caspi, Amir; Dennis, Brian R.; MinXSS Instrument Team, NIST-SURF Measurement Team

2018-01-01

Detection of soft X-rays (sxr) from the Sun provide direct information on coronal plasma at temperatures in excess of ~1 MK, but there have been relatively few solar spectrally resolved measurements from 0.5 – 10. keV. The Miniature X-ray Solar Spectrometer (MinXSS) CubeSat is the first solar science oriented CubeSat mission flown for the NASA Science Mission Directorate, and has provided measurements from 0.8 -12 keV, with resolving power ~40 at 5.9 keV, at a nominal ~10 second time cadence. MinXSS design and development has involved over 40 graduate students supervised by professors and professionals at the University of Colorado at Boulder. Instrument radiometric calibration was performed at the National Institute for Standard and Technology (NIST) Synchrotron Ultraviolet Radiation Facility (SURF) and spectral resolution determined from radioactive X-ray sources. The MinXSS spectra allow for determining coronal abundance variations for Fe, Mg, Ni, Ca, Si, S, and Ar in active regions and during flares. Measurements from the first of the twin CubeSats, MinXSS-1, have proven to be consistent with the Geostationary Operational Environmental Satellite (GOES) 0.1 – 0.8 nm energy flux. Simultaneous MinXSS-1 and Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) observations have provided the most complete sxr spectral coverage of flares in recent years. These combined measurements are vital in estimating the heating flare loops by non-thermal accelerated electrons. MinXSS-1 measurements have been combined with the Hinode X-ray Telescope (XRT) and Solar Dynamics Observatory Atmospheric Imaging Assembly (SDO-AIA) to further constrain the coronal temperature distribution during quiescent times. The structure of the temperature distribution (especially for T > 5 MK) is important for deducing heating processes in the solar atmosphere. MinXSS-1 observations yield some of the tightest constraints on the high temperature component of the coronal plasma, in the absence of the intermittent solar observations from the Focusing Optic X-ray Solar Imager (FOXSI) sounding rocket and the Nuclear Spectroscopic Telescope Array (NuSTAR).

Imaging Interplanetary CMEs at Radio Frequency From Solar Polar Orbit

NASA Astrophysics Data System (ADS)

Wu, Ji; Sun, Weiying; Zheng, Jianhua; Zhang, Cheng; Wang, Chi; Wang, C. B.; Wang, S.

Coronal mass ejections (CMEs) are violent discharges of plasma and magnetic fields from the Sun's corona. They have come to be recognized as the major driver of physical conditions in the Sun-Earth system. Consequently, the detection of CMEs is important for un-derstanding and ultimately predicting space weather conditions. The Solar Polar Orbit Radio Telescope (SPORT) is a proposed mission to observe the propagation of interplanetary CMEs from solar polar orbit. The main payload (radio telescope) on board SPORT will be an in-terferometric imaging radiometer working at the meter wavelength band, which will follow the propagation of interplanetary CMEs from a distance of a few solar radii to near 1 AU from solar polar orbit. The SPORT spacecraft will also be equipped with a set of optical and in situ measurement instruments such as a EUV solar telescope, a solar wind plasma experiment, a solar wind ion composition instrument, an energetic particle detector, a wave detector, a mag-netometer and an interplanetary radio burst tracker. In this paper, we first describe the current shortage of interplanetary CME observations. Next, the scientific motivation and objectives of SPORT are introduced. We discuss the basic specifications of the main radio telescope of SPORT with reference to the radio emission mechanisms and the radio frequency band to be observed. Finally, we discuss the key technologies of the SPORT mission, including the con-ceptual design of the main telescope, the image retrieval algorithm and the solar polar orbit injection. Other payloads and their respective observation objectives are also briefly discussed. Key words: Interplanetary CMEs; Interferometric imaging; Solar polar orbit; Radiometer.

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.

Flat Panel Space Based Space Surveillance Sensor

NASA Astrophysics Data System (ADS)

Kendrick, R.; Duncan, A.; Wilm, J.; Thurman, S. T.; Stubbs, D. M.; Ogden, C.

2013-09-01

Traditional electro-optical (EO) imaging payloads consist of an optical telescope to collect the light from the object scene and map the photons to an image plane to be digitized by a focal plane detector array. The size, weight, and power (SWaP) for the traditional EO imager is dominated by the optical telescope, driven primarily by the large optics, large stiff structures, and the thermal control needed to maintain precision free-space optical alignments. We propose a non-traditional Segmented Planar Imaging Detector for EO Reconnaissance (SPIDER) imager concept that is designed to substantially reduce SWaP, by at least an order of magnitude. SPIDER maximizes performance by providing a larger effective diameter (resolution) while minimizing mass and cost. SPIDER replaces the traditional optical telescope and digital focal plane detector array with a densely packed interferometer array based on emerging photonic integrated circuit (PIC) technologies. Lenslets couple light from the object into a set of waveguides on a PIC. Light from each lenslet is distributed among different waveguides by both field angle and optical frequency, and the lenslets are paired up to form unique interferometer baselines by combining light from different waveguides. The complex spatial coherence of the object (for each field angle, frequency, and baseline) is measured with a balanced four quadrature detection scheme. By the Van-Cittert Zernike Theorem, each measurement corresponds to a unique Fourier component of the incoherent object intensity distribution. Finally, an image reconstruction algorithm is used to invert all the data and form an image. Our approach replaces the large optics and structures required by a conventional telescope with PICs that are accommodated by standard lithographic fabrication techniques (e.g., CMOS fabrication). The standard EO payload integration and test process which involves precision alignment and test of optical components to form a diffraction limited telescope is, therefore, replaced by in-process integration and test as part of the PIC fabrication that substantially reduces associated schedule and cost. The low profile and low SWaP of a SPIDER system enables high resolution imaging with a payload that is similar in size and aspect ratio to a solar panel. This allows high resolution low cost options for space based space surveillance telescopes. The low SWaP design enables hosted payloads, cubesat designs as well as traditional bus options that are lower cost. We present a description of the concept and preliminary simulation and experimental data that demonstrate the imaging capabilities of the SPIDER technique.

NASA Marshall Space Flight Center solar observatory report, January - June 1993

NASA Technical Reports Server (NTRS)

Smith, J. E.

1993-01-01

This report provides a description of the NASA Marshall Space Flight Center's Solar Vector Magnetograph Facility and gives a summary of its observations and data reduction during January-June 1993. The systems that make up the facility are a magnetograph telescope, an H-alpha telescope, a Questar telescope, and a computer code.

NASA Marshall Space Flight Center Solar Observatory report, July - October 1993

NASA Technical Reports Server (NTRS)

Smith, J. E.

1994-01-01

This report provides a description of the NASA Marshall Space Flight Center's Solar Vector Magnetograph Facility and gives a summary of its observations and data reduction during June-October 1993. The systems that make up the facility are a magnetograph telescope, an H-alpha telescope, a Questar telescope, and a computer code.

NASA Marshall Space Flight Center Solar Observatory report, March - May 1994

NASA Technical Reports Server (NTRS)

Smith, J. E.

1994-01-01

This report provides a description of the NASA Marshall Space Flight Center's Solar Vector Magnetograph Facility and gives a summary of its observations and data reduction during March-May 1994. The systems that make up the facility are a magnetograph telescope, an H-alpha telescope, a Questar telescope, and a computer code.

The Engineering Development Array: A Low Frequency Radio Telescope Utilising SKA Precursor Technology

NASA Astrophysics Data System (ADS)

Wayth, Randall; Sokolowski, Marcin; Booler, Tom; Crosse, Brian; Emrich, David; Grootjans, Robert; Hall, Peter J.; Horsley, Luke; Juswardy, Budi; Kenney, David; Steele, Kim; Sutinjo, Adrian; Tingay, Steven J.; Ung, Daniel; Walker, Mia; Williams, Andrew; Beardsley, A.; Franzen, T. M. O.; Johnston-Hollitt, M.; Kaplan, D. L.; Morales, M. F.; Pallot, D.; Trott, C. M.; Wu, C.

2017-08-01

We describe the design and performance of the Engineering Development Array, which is a low-frequency radio telescope comprising 256 dual-polarisation dipole antennas working as a phased array. The Engineering Development Array was conceived of, developed, and deployed in just 18 months via re-use of Square Kilometre Array precursor technology and expertise, specifically from the Murchison Widefield Array radio telescope. Using drift scans and a model for the sky brightness temperature at low frequencies, we have derived the Engineering Development Array's receiver temperature as a function of frequency. The Engineering Development Array is shown to be sky-noise limited over most of the frequency range measured between 60 and 240 MHz. By using the Engineering Development Array in interferometric mode with the Murchison Widefield Array, we used calibrated visibilities to measure the absolute sensitivity of the array. The measured array sensitivity matches very well with a model based on the array layout and measured receiver temperature. The results demonstrate the practicality and feasibility of using Murchison Widefield Array-style precursor technology for Square Kilometre Array-scale stations. The modular architecture of the Engineering Development Array allows upgrades to the array to be rolled out in a staged approach. Future improvements to the Engineering Development Array include replacing the second stage beamformer with a fully digital system, and to transition to using RF-over-fibre for the signal output from first stage beamformers.

A retrospective of the GREGOR solar telescope in scientific literature

NASA Astrophysics Data System (ADS)

Denker, C.; von der Lühe, O.; Feller, A.; Arlt, K.; Balthasar, H.; Bauer, S.-M.; Bello González, N.; Berkefeld, Th.; Caligari, P.; Collados, M.; Fischer, A.; Granzer, T.; Hahn, T.; Halbgewachs, C.; Heidecke, F.; Hofmann, A.; Kentischer, T.; Klva{ňa, M.; Kneer, F.; Lagg, A.; Nicklas, H.; Popow, E.; Puschmann, K. G.; Rendtel, J.; Schmidt, D.; Schmidt, W.; Sobotka, M.; Solanki, S. K.; Soltau, D.; Staude, J.; Strassmeier, K. G.; Volkmer, R.; Waldmann, T.; Wiehr, E.; Wittmann, A. D.; Woche, M.

2012-11-01

In this review, we look back upon the literature, which had the GREGOR solar telescope project as its subject including science cases, telescope subsystems, and post-focus instruments. The articles date back to the year 2000, when the initial concepts for a new solar telescope on Tenerife were first presented at scientific meetings. This comprehensive bibliography contains literature until the year 2012, i.e., the final stages of commissioning and science verification. Taking stock of the various publications in peer-reviewed journals and conference proceedings also provides the ``historical'' context for the reference articles in this special issue of Astronomische Nachrichten/Astronomical Notes.

The Cherenkov Telescope Array: Exploring the Very-high-energy Sky from ESO's Paranal Site

NASA Astrophysics Data System (ADS)

Hofmann, W.

2017-06-01

The Cherenkov Telescope Array (CTA) is a next-generation observatory for ground-based very-high-energy gamma-ray astronomy, using the imaging atmospheric Cherenkov technique to detect and reconstruct gamma-ray induced air showers. The CTA project is planning to deploy 19 telescopes on its northern La Palma site, and 99 telescopes on its southern site at Paranal, covering the 20 GeV to 300 TeV energy domain and offering vastly improved performance compared to currently operating Cherenkov telescopes. The combination of three different telescope sizes (23-, 12- and 4-metre) allows cost-effective coverage of the wide energy range. CTA will be operated as a user facility, dividing observation time between a guest observer programme and large Key Science Projects (KSPs), and the data will be made public after a one-year proprietary period. The history of the project, the implementation of the arrays, and some of the major science goals and KSPs, are briefly summarised.

The single mirror small size telescope (SST-1M) of the Cherenkov Telescope Array

NASA Astrophysics Data System (ADS)

Aguilar, J. A.; Bilnik, W.; Borkowski, J.; Cadoux, F.; Christov, A.; della Volpe, D.; Favre, Y.; Heller, M.; Kasperek, J.; Lyard, E.; Marszałek, A.; Moderski, R.; Montaruli, T.; Porcelli, A.; Prandini, E.; Rajda, P.; Rameez, M.; Schioppa, E., Jr.; Troyano Pujadas, I.; Zietara, K.; Blocki, J.; Bogacz, L.; Bulik, T.; Frankowski, A.; Grudzinska, M.; Idźkowski, B.; Jamrozy, M.; Janiak, M.; Lalik, K.; Mach, E.; Mandat, D.; Michałowski, J.; Neronov, A.; Niemiec, J.; Ostrowski, M.; Paśko, P.; Pech, M.; Schovanek, P.; Seweryn, K.; Skowron, K.; Sliusar, V.; Stawarz, L.; Stodulska, M.; Stodulski, M.; Toscano, S.; Walter, R.; WiÈ©cek, M.; Zagdański, A.

2016-07-01

The Small Size Telescope with Single Mirror (SST-1M) is one of the proposed types of Small Size Telescopes (SST) for the Cherenkov Telescope Array (CTA). The CTA south array will be composed of about 100 telescopes, out of which about 70 are of SST class, which are optimized for the detection of gamma rays in the energy range from 5 TeV to 300 TeV. The SST-1M implements a Davies-Cotton optics with a 4 m dish diameter with a field of view of 9°. The Cherenkov light produced in atmospheric showers is focused onto a 88 cm wide hexagonal photo-detection plane, composed of 1296 custom designed large area hexagonal silicon photomultipliers (SiPM) and a fully digital readout and trigger system. The SST-1M camera has been designed to provide high performance in a robust as well as compact and lightweight design. In this contribution, we review the different steps that led to the realization of the telescope prototype and its innovative camera.

Conceptual design of a coherent optical system of modular imaging collectors (COSMIC). [telescope array deployed by space shuttle in 1990's

NASA Technical Reports Server (NTRS)

Nein, M. E.; Davis, B. G.

1982-01-01

The Coherent Optical System of Modular Imaging Collectors (COSMIC) is the design concept for a phase-coherent optical telescope array that may be placed in earth orbit by the Space Shuttle in the 1990s. The initial system module is a minimum redundancy array whose photon collecting area is three times larger than that of the Space Telescope, and possesses a one-dimensional resoution of better than 0.01 arcsec in the visible range. Thermal structural requirements are assessed. Although the coherent beam combination requirements will be met by an active control system, the COSMIC structural/thermal design must meet more stringent performance criteria than even those of the Space Telescope.

On the expected γ-ray emission from nearby flaring stars

NASA Astrophysics Data System (ADS)

Ohm, S.; Hoischen, C.

2018-02-01

Stellar flares have been extensively studied in soft X-rays (SXRs) by basically every X-ray mission. Hard X-ray (HXR) emission from stellar superflares, however, have only been detected from a handful of objects over the past years. One very extreme event was the superflare from the young M-dwarf DG CVn binary star system, which triggered Swift/BAT as if it was a γ-ray burst. In this work, we estimate the expected γ-ray emission from DG CVn and the most extreme stellar flares by extrapolating from solar flares based on measured solar energetic particles (SEPs), as well as thermal and non-thermal emission properties. We find that ions are plausibly accelerated in stellar superflares to 100 GeV energies, and possibly up to TeV energies in the associated coronal mass ejections. The corresponding π0-decay γ-ray emission could be detectable from stellar superflares with ground-based γ-ray telescopes. On the other hand, the detection of γ-ray emission implies particle densities high enough that ions suffer significant losses due to inelastic proton-proton scattering. The next-generation Cherenkov Telescope Array (CTA) should be able to probe superflares from M dwarfs in the solar neighbourhood and constrain the energy in interacting cosmic rays and/or their maximum energy. The detection of γ-ray emission from stellar flares would open a new window for the study of stellar physics, the underlying physical processes in flares and their impact on habitability of planetary systems.

Thermal Consideration of SWIFT XRT Radiator At-35C or Colder in Low Earth Orbit

NASA Technical Reports Server (NTRS)

Choi, Michael K.

2000-01-01

The X-Ray Telescope (XRT) is an instrument on the National Aeronautics and Space Administration (NASA) SWIFT spacecraft. The thermoelectric cooler (TEC) for the charge coupled device (CCD) of the XRT requires a radiator temperature of -35 C or colder, and a goal of -55 C to minimize the damage by radiation. The waste heat rejected from the TEC to the radiator is in the 8 W to 20 W range. In the Phase A baseline design, the XRT radiator is mounted to the rear end of the XRT telescope tube and is very close to the bottom closeout of the spacecraft bus. The bottom closeout is multi-layer insulation (MLI) blankets. At sun angles between 90 deg and 180 deg, there is direct solar impingement on the bottom closeout. When the rolls +/- 5 deg, the XRT radiator is exposed to direct solar radiation. The radiator also has a view factor to the solar arrays. The results of thermal analysis showed that the flight temperature prediction of the radiator exceeds the temperature requirement of -35 C substantially at sun angles from 110 deg to 180 deg. A new location on the anti-sun side of the spacecraft is proposed for the radiator. It requires a heat pipe to couple the TEC and the radiator thermally. The results of thermal analysis show that the flight temperature prediction of the proposed radiator meets the temperature requirement at all sun angles.

GCT, the Gamma-ray Cherenkov Telescope for multi-TeV science with the Cherenkov Telescope Array

NASA Astrophysics Data System (ADS)

Sol, H.; Dournaux, J.-L.; Laporte, P.

2016-12-01

GCT is a gamma-ray telescope proposed for the high-energy section of the Cherenkov Telescope Array (CTA). A GCT prototype telescope has been designed, built and installed at the Observatoire de Paris in Meudon. Equipped with the first GCT prototype camera developed by an international collaboration, the complete GCT prototype was inaugurated in December 2015, after getting its first Cherenkov light on the night sky in November. The phase of tests, assessment, and optimisation is now coming to an end. Pre-production of the first GCT telescopes and cameras should start in 2017, for an installation on the Chilean site of CTA in 2018.

Operational considerations to reduce solar array loads

NASA Technical Reports Server (NTRS)

Gerstenmaier, W.

1992-01-01

The key parameters associated with solar array plume loads are examined, and operational considerations aimed at minimizing the effect of the Shuttle plumes on the Space Station solar arrays are discussed. These include solar array pointing to reduce loads and restrictions on Shuttle piloting. Particular attention is given to the method used to obtain the forcing functions (thruster time firing histories) for solar array plume calculation.

The gamma-ray Cherenkov telescope for the Cherenkov telescope array

NASA Astrophysics Data System (ADS)

Tibaldo, L.; Abchiche, A.; Allan, D.; Amans, J.-P.; Armstrong, T. P.; Balzer, A.; Berge, D.; Boisson, C.; Bousquet, J.-J.; Brown, A. M.; Bryan, M.; Buchholtz, G.; Chadwick, P. M.; Costantini, H.; Cotter, G.; Daniel, M. K.; De Franco, A.; De Frondat, F.; Dournaux, J.-L.; Dumas, D.; Ernenwein, J.-P.; Fasola, G.; Funk, S.; Gironnet, J.; Graham, J. A.; Greenshaw, T.; Hervet, O.; Hidaka, N.; Hinton, J. A.; Huet, J.-M.; Jankowsky, D.; Jegouzo, I.; Jogler, T.; Kraus, M.; Lapington, J. S.; Laporte, P.; Lefaucheur, J.; Markoff, S.; Melse, T.; Mohrmann, L.; Molyneux, P.; Nolan, S. J.; Okumura, A.; Osborne, J. P.; Parsons, R. D.; Rosen, S.; Ross, D.; Rowell, G.; Rulten, C. B.; Sato, Y.; Sayède, F.; Schmoll, J.; Schoorlemmer, H.; Servillat, M.; Sol, H.; Stamatescu, V.; Stephan, M.; Stuik, R.; Sykes, J.; Tajima, H.; Thornhill, J.; Trichard, C.; Vink, J.; Watson, J. J.; White, R.; Yamane, N.; Zech, A.; Zink, A.; Zorn, J.; CTA Consortium

2017-01-01

The Cherenkov Telescope Array (CTA) is a forthcoming ground-based observatory for very-high-energy gamma rays. CTA will consist of two arrays of imaging atmospheric Cherenkov telescopes in the Northern and Southern hemispheres, and will combine telescopes of different types to achieve unprecedented performance and energy coverage. The Gamma-ray Cherenkov Telescope (GCT) is one of the small-sized telescopes proposed for CTA to explore the energy range from a few TeV to hundreds of TeV with a field of view ≳ 8° and angular resolution of a few arcminutes. The GCT design features dual-mirror Schwarzschild-Couder optics and a compact camera based on densely-pixelated photodetectors as well as custom electronics. In this contribution we provide an overview of the GCT project with focus on prototype development and testing that is currently ongoing. We present results obtained during the first on-telescope campaign in late 2015 at the Observatoire de Paris-Meudon, during which we recorded the first Cherenkov images from atmospheric showers with the GCT multi-anode photomultiplier camera prototype. We also discuss the development of a second GCT camera prototype with silicon photomultipliers as photosensors, and plans toward a contribution to the realisation of CTA.

Observing the Sun with NuSTAR

NASA Astrophysics Data System (ADS)

Kohler, Susanna

2016-07-01

The Nuclear Spectroscopic Telescope Array (NuSTAR) is a space telescope primarily designed to detect high-energy X-rays from faint, distant astrophysical sources. Recently, however, its occasionally been pointing much closer to home, with the goal of solving a few longstanding mysteries about the Sun.Intensity maps from an observation of a quiet-Sun region near the north solar pole and an active region just below the solar limb. The quiet-Sun data will be searched for small flares that could be heating the solar corona, and the high-altitude emission above the limb may provide clues about particle acceleration. [Adapted from Grefenstette et al. 2016]An Unexpected TargetThough we have a small fleet of space telescopes designed to observe the Sun, theres an important gap: until recently, there was no focusing telescope making solar observations in the hard X-ray band (above ~3 keV). Conveniently, there is a tool capable of doing this: NuSTAR.Though NuSTARs primary mission is to observe faint astrophysical X-ray sources, a team of scientists has recently conducted a series of observations in which NuSTAR was temporarily repurposed and turned to focus on the Sun instead.These observations pose an interesting challenge precisely because of NuSTARs extreme sensitivity: pointing at such a nearby, bright source can quickly swamp the detectors. But though the instrument cant be used to observe the bright flares and outbursts from the Sun, its the perfect tool for examining the parts of the Sun weve been unable to explore in hard X-rays before now such as faint flares, or the quiet, inactive solar surface.In a recently published study led by Brian Grefenstette (California Institute of Technology), the team describes the purpose and initial results of NuSTARs first observations of the Sun.Solar MysteriesWhat is NuSTAR hoping to accomplish with its solar observations? There are two main questions that hard X-ray observations may help to answer.How are particles accelerated in solar flares?The process of electron acceleration during solar flares is not well understood. When a flare-producing active region is occulted by the solar limb, NuSTAR will able to directly observe the flare loop above the solar surface which is where that acceleration is thought to happen.How is the solar corona heated?The solar corona is a toasty 13 million Kelvin significantly warmer than the ~6000 K solar photosphere. So how is the corona heated? One proposed explanation is that the Suns surface constantly emits tiny nanoflares in active regions, or even in the quiet Sun that are so faint that we havent detected them. But with its high sensitivity, NuSTAR may be able to!The first NuSTAR full-disk mosaic of the Sun. The checkerboard pattern is an artifact of the detectors being hit by particles from active regions outside of the field of view a problem which will be reduced as the Sun enters the upcoming quieter part of the solar cycle. [Adapted from Grefenstette et al. 2016]First ObservationsIn NuSTARs first four observations of the Sun, the team unexpectedly observed a major flare (which unsurprisingly swamped the detectors), watched the emission above an active region that was hidden by the solar limb, stared at a section of quiet Sun near the north solar pole, and composed a full-disk mosaic of the solar surface from 16 12 x 12 tiles.All of these initial observations are currently being carefully analyzed and will be presented in detail in future publications. In the meantime, NuSTAR has demonstrated its effectiveness in detecting faint emission in solar hard X-rays, proving that it will be a powerful tool for heliophysics as well as for astrophysics. We look forward to seeing the future results from this campaign!CitationBrian W. Grefenstette et al 2016 ApJ 826 20. doi:10.3847/0004-637X/826/1/20

The ASTRI/CTA mini-array software system

NASA Astrophysics Data System (ADS)

Tosti, Gino; Schwarz, Joseph; Antonelli, Lucio Angelo; Trifoglio, Massimo; Catalano, Osvaldo; Maccarone, Maria Concetta; Leto, Giuseppe; Gianotti, Fulvio; Canestrari, Rodolfo; Giro, Enrico; Fiorini, Mauro; La Palombara, Nicola; Pareschi, Giovanni; Stringhetti, Luca; Vercellone, Stefano; Conforti, Vito; Tanci, Claudio; Bruno, Pietro; Grillo, Alessandro; Testa, Vincenzo; di Paola, Andrea; Gallozzi, Stefano

2014-07-01

ASTRI (Astrofisica con Specchi a Tecnologia Replicante Italiana) is a Flagship Project financed by the Italian Ministry of Education, University and Research, and led by INAF, the Italian National Institute of Astrophysics. The main goals of the ASTRI project are the realization of an end-to-end prototype of a Small Size Telescope (SST) for the Cherenkov Telescope Array (CTA) in a dual- mirror configuration (SST-2M) and, subsequently, of a mini-array comprising seven SST-2M telescopes. The mini-array will be placed at the final CTA Southern Site, which will be part of the CTA seed array, around which the whole CTA observatory will be developed. The Mini-Array Software System (MASS) will provide a comprehensive set of tools to prepare an observing proposal, to perform the observations specified therein (monitoring and controlling all the hardware components of each telescope), to analyze the acquired data online and to store/retrieve all the data products to/from the archive. Here we present the main features of the MASS and its first version, to be tested on the ASTRI SST-2M prototype that will be installed at the INAF observing station located at Serra La Nave on Mount Etna in Sicily.

CLOSE-UP LOOK AT A JET NEAR A BLACK HOLE

NASA Technical Reports Server (NTRS)

2002-01-01

[top left] - This radio image of the galaxy M87, taken with the Very Large Array (VLA) radio telescope in February 1989, shows giant bubble-like structures where radio emission is thought to be powered by the jets of subatomic particles coming from the the galaxy's central black hole. The false color corresponds to the intensity of the radio energy being emitted by the jet. M87 is located 50 million light-years away in the constellation Virgo. Credit: National Radio Astronomy Observatory/National Science Foundation [top right] - A visible light image of the giant elliptical galaxy M87, taken with NASA Hubble Space Telescope's Wide Field Planetary Camera 2 in February 1998, reveals a brilliant jet of high-speed electrons emitted from the nucleus (diagonal line across image). The jet is produced by a 3-billion-solar-mass black hole. Credit: NASA and John Biretta (STScI/JHU) [bottom] - A Very Long Baseline Array (VLBA) radio image of the region close to the black hole, where an extragalactic jet is formed into a narrow beam by magnetic fields. The false color corresponds to the intensity of the radio energy being emitted by the jet. The red region is about 1/10 light-year across. The image was taken in March 1999. Credit: National Radio Astronomy Observatory/Associated Universities, Inc.

Operation and performance of the EEE network array for the detection of cosmic rays

NASA Astrophysics Data System (ADS)

Abbrescia, M.; Avanzini, C.; Baldini, L.; Baldini Ferroli, R.; Batignani, G.; Bencivenni, G.; Bossini, E.; Chiavassa, A.; Cicalò, C.; Cifarelli, L.; Coccia, E.; Corvaglia, A.; De Gruttola, D.; De Pasquale, S.; Di Giovanni, A.; D'Incecco, M.; Dreucci, M.; Fabbri, F. L.; Fattibene, E.; Ferraro, A.; Frolov, V.; Galeotti, P.; Garbini, M.; Gemme, G.; Gnesi, I.; Grazzi, S.; Gustavino, C.; Hatzifotiadou, D.; La Rocca, P.; Licciulli, F.; Maggiora, A.; Maragoto Rodriguez, O.; Maron, G.; Martelli, B.; Mazziotta, M. N.; Miozzi, S.; Nania, R.; Noferini, F.; Nozzoli, F.; Panareo, M.; Panetta, M. P.; Paoletti, R.; Park, W.; Perasso, L.; Pilo, F.; Piragino, G.; Riggi, F.; Righini, G. C.; Sartorelli, G.; Scapparone, E.; Schioppa, M.; Scribano, A.; Selvi, M.; Serci, S.; Siddi, E.; Squarcia, S.; Stori, L.; Taiuti, M.; Terreni, G.; Visnyei, O. B.; Vistoli, M. C.; Votano, L.; Williams, M. C. S.; Zani, S.; Zichichi, A.; Zuyeuski, R.

2017-02-01

The EEE (Extreme Energy Events) Project is an experiment for the detection of cosmic ray muons by means of a sparse array of telescopes, each made of three Multigap Resistive Plate Chambers (MRPC), distributed over all the Italian territory and at CERN. The main scientific goals of the Project are the investigation of the properties of the local muon flux, the detection of Extensive Air Showers (EAS) and the search for long-distance correlations between far telescopes. The Project is also characterized by a strong educational and outreach aspect since the telescopes are managed by teams of students and teachers who had previously constructed them at CERN. In this paper an overall description of the experiment is given, including the design, construction and performance of the telescopes. The operation of the whole array, which currently consists of more than 50 telescopes, is also presented by showing the most recent physics results.

The Advanced Technology Solar Telescope mount assembly

NASA Astrophysics Data System (ADS)

Warner, Mark; Cho, Myung; Goodrich, Bret; Hansen, Eric; Hubbard, Rob; Lee, Joon Pyo; Wagner, Jeremy

2006-06-01

When constructed on the summit of Haleakala on the island of Maui, Hawaii, the Advanced Technology Solar Telescope (ATST) will be the world's largest solar telescope. The ATST is a unique design that utilizes a state-of-the-art off-axis Gregorian optical layout with five reflecting mirrors delivering light to a Nasmyth instrument rotator, and nine reflecting mirrors delivering light to an instrument suite located on a large diameter rotating coude lab. The design of the telescope mount structure, which supports and positions the mirrors and scientific instruments, has presented noteworthy challenges to the ATST engineering staff. Several novel design solutions, as well as adaptations of existing telescope technologies to the ATST application, are presented in this paper. Also shown are plans for the control system and drives of the structure.

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.

Concept design of an 80-dual polarization element cryogenic phased array camera for the Arecibo Radio Telescope

NASA Astrophysics Data System (ADS)

Cortes-Medellin, German; Parshley, Stephen; Campbell, Donald B.; Warnick, Karl F.; Jeffs, Brian D.; Ganesh, Rajagopalan

2016-08-01

This paper presents the current concept design for ALPACA (Advanced L-Band Phased Array Camera for Arecibo) an L-Band cryo-phased array instrument proposed for the 305 m radio telescope of Arecibo. It includes the cryogenically cooled front-end with 160 low noise amplifiers, a RF-over-fiber signal transport and a digital beam former with an instantaneous bandwidth of 312.5 MHz per channel. The camera will digitally form 40 simultaneous beams inside the available field of view of the Arecibo telescope optics, with an expected system temperature goal of 30 K.

Advanced photovoltaic solar array design assessment

NASA Technical Reports Server (NTRS)

Stella, Paul; Scott-Monck, John

1987-01-01

The Advanced Photovoltaic Solar Array (APSA) program seeks to bring to flight readiness a solar array that effectively doubles the specific power of the Solar Array Flight Experiment/Solar Electric Propulsion (SAFE/SEP) design that was successfully demonstrated during the Shuttle 41-D mission. APSA is a critical intermediate milestone in the effort to demonstrate solar array technologies capable of 300 W/kg and 300 W/square m at beginning of life (BOL). It is not unreasonable to anticipate the development of solar array designs capable of 300 W/kg at BOL for operational power levels approx. greater than 25 kW sub e. It is also quite reasonable to expect that high performance solar arrays capable of providing at least 200 W/kg at end of life for most orbits now being considered by mission planners will be realized in the next decade.

NST: Thermal Modeling for a Large Aperture Solar Telescope

NASA Astrophysics Data System (ADS)

Coulter, Roy

2011-05-01

Late in the 1990s the Dutch Open Telescope demonstrated that internal seeing in open, large aperture solar telescopes can be controlled by flushing air across the primary mirror and other telescope structures exposed to sunlight. In that system natural wind provides a uniform air temperature throughout the imaging volume, while efficiently sweeping heated air away from the optics and mechanical structure. Big Bear Solar Observatory's New Solar Telescope (NST) was designed to realize that same performance in an enclosed system by using both natural wind through the dome and forced air circulation around the primary mirror to provide the uniform air temperatures required within the telescope volume. The NST is housed in a conventional, ventilated dome with a circular opening, in place of the standard dome slit, that allows sunlight to fall only on an aperture stop and the primary mirror. The primary mirror is housed deep inside a cylindrical cell with only minimal openings in the side at the level of the mirror. To date, the forced air and cooling systems designed for the NST primary mirror have not been implemented, yet the telescope regularly produces solar images indicative of the absence of mirror seeing. Computational Fluid Dynamics (CFD) analysis of the NST primary mirror system along with measurements of air flows within the dome, around the telescope structure, and internal to the mirror cell are used to explain the origin of this seemingly incongruent result. The CFD analysis is also extended to hypothetical systems of various scales. We will discuss the results of these investigations.

Modeling and reconfiguration of solar photovoltaic arrays under non-uniform shadow conditions

NASA Astrophysics Data System (ADS)

Nguyen, Dung Duc

Mass production and use of electricity generated from solar energy has become very common recently because of the environmental threats arising from the production of electricity from fossil fuels and nuclear power. The obvious benefits of solar energy are clean energy production and infinite supply of daylight. The main disadvantage is the high cost. In these photovoltaic systems, semiconductor materials convert the solar light into electrical energy. Current versus voltage characteristics of the solar cells are nonlinear, thus leading to technical control challenges. In the first order approximation, output power of a solar array is proportional to the irradiance of sunlight. However, in many applications, such as solar power plants, building integrated photovoltaic or solar tents, the solar photovoltaic arrays might be illuminated non-uniformly. The cause of non-uniform illumination may be the shadow of clouds, the trees, booms, neighbor's houses, or the shadow of one solar array on the other, etc. This further leads to nonlinearities in characteristics. Because of the nature of the electrical characteristics of solar cells, the maximum power losses are not proportional to the shadow, but magnify nonlinearly [1]. Further, shadows of solar PV array can cause other undesired effects: (1) The power actually generated from the solar PV array is much less than designed. At some systems, the annual losses because of the shadow effects can be reached 10%. Thus, the probability for "loss of load" increases [2]. (2) The local hot spot in the shaded part of the solar PV array can damage the solar cells. The shaded solar cells may be work on the negative voltage region and become a resistive load and absorb power. Bypass diodes are sometimes connected parallel to solar cells to protect them from damage. However, in most cases, just one diode is connected in parallel to group of solar cells [3], and this hidden the potential power output of the array. This proposed research will focus on the development of an adaptable solar array that is able to optimize power output, reconfigure itself when solar cells are damaged and create controllable output voltages and currents. This study will be a technological advancement over the existing technology of solar PV. Presently solar arrays are fixed arrays that require external device to control their output. In this research, the solar array will be able to self-reconfigure, leading to the following advantages: (1) Higher efficiency because no external devices are used. (2) Can reach maximum possible output power that is much higher than the maximum power of fixed solar arrays by arranging the solar cells in optimized connections. (3) Elimination of the hot spot effects. The proposed research has the following goals: First, to create a modeling and computing algorithm, which is able to simulate and analyze the effects of non-uniform changing shadows on the output power of solar PV arrays. Our model will be able to determine the power losses in each solar cell and the collective hot spots of an array. Second, to propose new methods, which are able to predict the performance of solar PV arrays under shadow conditions for long term (days, months, years). Finally, to develop adaptive reconfiguration algorithms to reconfigure connections within solar PV arrays in real time, under shadow conditions, in order to optimize output power.

NASA Marshall Space Flight Center Solar Observatory Report, July to December 1992

NASA Technical Reports Server (NTRS)

Smith, J. E.

1993-01-01

This report provides a description of the NASA Marshall Space Flight Center's Solar Vector Magnetograph Facility and gives a summary of its observations and data reduction during July-December 1992. The systems that make up the facility are a magnetograph telescope, an H-alpha telescope, a Questar telescope, and a computer code.

NASA Marshall Space Flight Center Solar Observatory report, January - June 1992

NASA Technical Reports Server (NTRS)

Smith, James E.

1992-01-01

This report provides a description of the NASA Marshall Space Flight Center's Solar Vector Magnetograph Facility and gives a summary of its observations and data reduction during Jan. to Jun. 1992. The systems that make up the facility are a magnetograph telescope, and H-alpha telescope, a Questar telescope, and a computer code.

Design and Deployment of a Multichroic Polarimeter Array on the Atacama Cosmology Telescope

NASA Technical Reports Server (NTRS)

Datta, R.; Austermann, J.; Beall, J. A.; Becker, D.; Coughlin, K. P.; Duff, S. M.; Gallardo, P.A.; Grace, E.; Hasselfield, M.; Henderson, S. W.;

Design and Deployment of a Multichroic Polarimeter Array on the Atacama Cosmology Telescope

NASA Astrophysics Data System (ADS)

Datta, R.; Austermann, J.; Beall, J. A.; Becker, D.; Coughlin, K. P.; Duff, S. M.; Gallardo, P. A.; Grace, E.; Hasselfield, M.; Henderson, S. W.; Hilton, G. C.; Ho, S. P.; Hubmayr, J.; Koopman, B. J.; Lanen, J. V.; Li, D.; McMahon, J.; Munson, C. D.; Nati, F.; Niemack, M. D.; Page, L.; Pappas, C. G.; Salatino, M.; Schmitt, B. L.; Schillaci, A.; Simon, S. M.; Staggs, S. T.; Stevens, J. R.; Vavagiakis, E. M.; Ward, J. T.; Wollack, E. J.

2016-08-01

We present the design and the preliminary on-sky performance with respect to beams and passbands of a multichroic polarimeter array covering the 90 and 146 GHz cosmic microwave background bands and its enabling broad-band optical system recently deployed on the Atacama Cosmology Telescope (ACT). The constituent pixels are feedhorn-coupled multichroic polarimeters fabricated at NIST. This array is coupled to the ACT telescope via a set of three silicon lenses incorporating novel broad-band metamaterial anti-reflection coatings. This receiver represents the first multichroic detector array deployed for a CMB experiment and paves the way for the extensive use of multichroic detectors and broad-band optical systems in the next generation of CMB experiments.

Highlights from the Telescope Array Experiment

NASA Astrophysics Data System (ADS)

Sagawa, H.

2014-10-01

The Telescope Array (TA) is the largest experiment in the Northern Hemisphere currently studying the origin and nature of ultra-high-energy cosmic rays above ˜1018 eV by measuring their energy spectrum, mass composition, and arrival directions. It is located in the western desert of central Utah, USA. The TA detector consists of a surface array of 507 scintillation counters, deployed on a square grid of 1.2-km spacing that covers approximately 700 km2, and 38 fluorescence telescopes located at three sites looking over the surface array. The TA commenced hybrid observation with both sets of detectors in 2008. Here, we present recent results from these 5 years of data and outline our ongoing and near future plans.

Solar array study for solar electric propulsion spacecraft for the Encke rendezvous mission

NASA Technical Reports Server (NTRS)

Sequeira, E. A.; Patterson, R. E.

1974-01-01

The work is described which was performed on the design, analysis and performance of a 20 kW rollup solar array capable of meeting the design requirements of a solar electric spacecraft for the 1980 Encke rendezvous mission. To meet the high power requirements of the proposed electric propulsion mission, solar arrays on the order of 186.6 sq m were defined. Because of the large weights involved with arrays of this size, consideration of array configurations is limited to lightweight, large area concepts with maximum power-to-weight ratios. Items covered include solar array requirements and constraints, array concept selection and rationale, structural and electrical design considerations, and reliability considerations.

Innovative enclosure dome/observing aperture system design for the MROI Array Telescopes

NASA Astrophysics Data System (ADS)

Busatta, A.; Marchiori, G.; Mian, S.; Payne, I.; Pozzobon, M.

2010-07-01

The close-pack array of the MROI necessitated an original design for the Unit Telescope Enclosure (UTE) at Magdalena Ridge Observatory. The Magdalena Ridge Observatory Interferometer (MROI) is a project which comprises an array of up to ten (10) 1.4m diameter mirror telescopes arranged in a "Y" configuration. Each of these telescopes will be housed inside a Unit Telescope Enclosure (UTE) which are relocatable onto any of 28 stations. The most compact configuration includes all ten telescopes, several of which are at a relative distance of less than 8m center to center from each other. Since the minimum angle of the field of regard is 30° with respect to the horizon, it is difficult to prevent optical blockage caused by adjacent UTEs in this compact array. This paper presents the design constraints inherent in meeting the requirement for the close-pack array. An innovative design enclosure was created which incorporates an unique dome/observing aperture system. The description of this system focuses on how the field of regard requirement led to an unique and highly innovative concept that had to be able to operate in the harsh environmental conditions encountered at an altitude of 10,460ft (3,188m). Finally, we describe the wide use of composites materials and structures (e.g. glass/carbon fibres, sandwich panels etc.) on the aperture system which represents the only way to guarantee adequate thermal and environmental protection, compactness, structural stability and limited power consumption due to reduced mass.

Calibration strategies for the Cherenkov Telescope Array

NASA Astrophysics Data System (ADS)

Gaug, Markus; Berge, David; Daniel, Michael; Doro, Michele; Förster, Andreas; Hofmann, Werner; Maccarone, Maria C.; Parsons, Dan; de los Reyes Lopez, Raquel; van Eldik, Christopher

2014-08-01

The Central Calibration Facilities workpackage of the Cherenkov Telescope Array (CTA) observatory for very high energy gamma ray astronomy defines the overall calibration strategy of the array, develops dedicated hardware and software for the overall array calibration and coordinates the calibration efforts of the different telescopes. The latter include LED-based light pulsers, and various methods and instruments to achieve a calibration of the overall optical throughput. On the array level, methods for the inter-telescope calibration and the absolute calibration of the entire observatory are being developed. Additionally, the atmosphere above the telescopes, used as a calorimeter, will be monitored constantly with state-of-the-art instruments to obtain a full molecular and aerosol profile up to the stratosphere. The aim is to provide a maximal uncertainty of 10% on the reconstructed energy-scale, obtained through various independent methods. Different types of LIDAR in combination with all-sky-cameras will provide the observatory with an online, intelligent scheduling system, which, if the sky is partially covered by clouds, gives preference to sources observable under good atmospheric conditions. Wide-field optical telescopes and Raman Lidars will provide online information about the height-resolved atmospheric extinction, throughout the field-of-view of the cameras, allowing for the correction of the reconstructed energy of each gamma-ray event. The aim is to maximize the duty cycle of the observatory, in terms of usable data, while reducing the dead time introduced by calibration activities to an absolute minimum.

A solar station in Ica - Mutsumi Ishitsuka: a research center to improve education at the university and schools

NASA Astrophysics Data System (ADS)

Terrazas-Ramos, Raúl

2012-07-01

The San Luis Gonzaga National University of Ica has built a solar station, in collaboration with the Geophysical Institute of Peru, the National Astronomical Observatory of Japan and the Hida Observatory. The Solar Station has the following equipment: a digital Spectrograph Solar Refractor Telescope Takahashi 15 cm aperture, 60 cm reflector telescope aperture, a magnetometer-MAGDAS/CPNM and a Burst Monitor Telescope Solar-FMT (Project CHAIN). These teams support the development of astronomical science and Ica in Peru, likewise contributing to science worldwide. The development of basic science will be guaranteed when university students, professors and researchers work together. The Solar Station will be useful for studying the different levels of university education and also for the general public. The Solar Station will be a good way to spread science in the region through public disclosure.

A modified S-DIMM+: applying additional height grids for characterizing daytime seeing profiles

NASA Astrophysics Data System (ADS)

Wang, Zhiyong; Zhang, Lanqiang; Kong, Lin; Bao, Hua; Guo, Youming; Rao, Xuejun; Zhong, Libo; Zhu, Lei; Rao, Changhui

2018-07-01

Characterization of daytime atmospheric turbulence profiles is needed for the design of a multi-conjugate adaptive optical system. S-DIMM+ (solar differential image motion monitor+) is a technique to measure vertical seeing profiles. However, the number of height grids will be limited by the lenslet array of the wide-field Shack-Hartmann wavefront sensor (SHWFS). A small number of subaperture lenslet arrays will lead to a coarse height grid over the atmosphere, which can result in difficulty in finding the location of strong-turbulence layers and overestimates of the turbulence strength for the measured layers. To address this problem, we propose a modified S-DIMM+ method to measure seeing profiles iteratively with decreasing altitude range for a given number of height grids; finally they will be combined as a new seeing profile, with a denser and more uniform distribution of height grids. This method is tested with simulations and recovers the input height and contribution perfectly. Furthermore, this method is applied to the 102 data-sequences recorded from the 1-m New Vacuum Solar Telescope at Fuxian Solar Observatory, 55 of which were recorded at local time between 13:40 and 14:35 on 2016 October 6, and the other 47 between 12:50 and 13:40 on 2017 October 5. A 7x7 lenslet array of SHWFS is used to generate a 16-layer height grid to 15 km, each with 1 km height separation. The experimental results show that the turbulence has three origins in the lower (0-2 km) layers, the higher (3-6 km) layers and the uppermost (≥7 km) layers.

Observing the Sun with the Atacama Large Millimeter/submillimeter Array (ALMA): Fast-Scan Single-Dish Mapping

NASA Astrophysics Data System (ADS)

White, S. M.; Iwai, K.; Phillips, N. M.; Hills, R. E.; Hirota, A.; Yagoubov, P.; Siringo, G.; Shimojo, M.; Bastian, T. S.; Hales, A. S.; Sawada, T.; Asayama, S.; Sugimoto, M.; Marson, R. G.; Kawasaki, W.; Muller, E.; Nakazato, T.; Sugimoto, K.; Brajša, R.; Skokić, I.; Bárta, M.; Kim, S.; Remijan, A. J.; de Gregorio, I.; Corder, S. A.; Hudson, H. S.; Loukitcheva, M.; Chen, B.; De Pontieu, B.; Fleishmann, G. D.; Gary, D. E.; Kobelski, A.; Wedemeyer, S.; Yan, Y.

2017-07-01

The Atacama Large Millimeter/submillimeter Array (ALMA) radio telescope has commenced science observations of the Sun starting in late 2016. Since the Sun is much larger than the field of view of individual ALMA dishes, the ALMA interferometer is unable to measure the background level of solar emission when observing the solar disk. The absolute temperature scale is a critical measurement for much of ALMA solar science, including the understanding of energy transfer through the solar atmosphere, the properties of prominences, and the study of shock heating in the chromosphere. In order to provide an absolute temperature scale, ALMA solar observing will take advantage of the remarkable fast-scanning capabilities of the ALMA 12 m dishes to make single-dish maps of the full Sun. This article reports on the results of an extensive commissioning effort to optimize the mapping procedure, and it describes the nature of the resulting data. Amplitude calibration is discussed in detail: a path that uses the two loads in the ALMA calibration system as well as sky measurements is described and applied to commissioning data. Inspection of a large number of single-dish datasets shows significant variation in the resulting temperatures, and based on the temperature distributions, we derive quiet-Sun values at disk center of 7300 K at λ = 3 mm and 5900 K at λ = 1.3 mm. These values have statistical uncertainties of about 100 K, but systematic uncertainties in the temperature scale that may be significantly larger. Example images are presented from two periods with very different levels of solar activity. At a resolution of about 25'', the 1.3 mm wavelength images show temperatures on the disk that vary over about a 2000 K range. Active regions and plages are among the hotter features, while a large sunspot umbra shows up as a depression, and filament channels are relatively cool. Prominences above the solar limb are a common feature of the single-dish images.

A Near-Infrared and Thermal Imager for Mapping Titan's Surface Features

NASA Technical Reports Server (NTRS)

Aslam, S.; Hewagma, T.; Jennings, D. E.; Nixon, C.

2012-01-01

Approximately 10% of the solar insolation reaches the surface of Titan through atmospheric spectral windows. We will discuss a filter based imaging system for a future Titan orbiter that will exploit these windows mapping surface features, cloud regions, polar storms. In the near-infrared (NIR), two filters (1.28 micrometer and 1.6 micrometer), strategically positioned between CH1 absorption bands, and InSb linear array pixels will explore the solar reflected radiation. We propose to map the mid, infrared (MIR) region with two filters: 9.76 micrometer and 5.88-to-6.06 micrometers with MCT linear arrays. The first will map MIR thermal emission variations due to surface albedo differences in the atmospheric window between gas phase CH3D and C2H4 opacity sources. The latter spans the crossover spectral region where observed radiation transitions from being dominated by thermal emission to solar reflected light component. The passively cooled linear arrays will be incorporated into the focal plane of a light-weight thin film stretched membrane 10 cm telescope. A rad-hard ASIC together with an FPGA will be used for detector pixel readout and detector linear array selection depending on if the field-of-view (FOV) is looking at the day- or night-side of Titan. The instantaneous FOV corresponds to 3.1, 15.6, and 31.2 mrad for the 1, 5, and 10 micrometer channels, respectively. For a 1500 km orbit, a 5 micrometer channel pixel represents a spatial resolution of 91 m, with a FOV that spans 23 kilometers, and Titan is mapped in a push-broom manner as determined by the orbital path. The system mass and power requirements are estimated to be 6 kg and 5 W, respectively. The package is proposed for a polar orbiter with a lifetime matching two Saturn seasons.

LOFAR tied-array imaging and spectroscopy of solar S bursts

NASA Astrophysics Data System (ADS)

Morosan, D. E.; Gallagher, P. T.; Zucca, P.; O'Flannagain, A.; Fallows, R.; Reid, H.; Magdalenić, J.; Mann, G.; Bisi, M. M.; Kerdraon, A.; Konovalenko, A. A.; MacKinnon, A. L.; Rucker, H. O.; Thidé, B.; Vocks, C.; Alexov, A.; Anderson, J.; Asgekar, A.; Avruch, I. M.; Bentum, M. J.; Bernardi, G.; Bonafede, A.; Breitling, F.; Broderick, J. W.; Brouw, W. N.; Butcher, H. R.; Ciardi, B.; de Geus, E.; Eislöffel, J.; Falcke, H.; Frieswijk, W.; Garrett, M. A.; Grießmeier, J.; Gunst, A. W.; Hessels, J. W. T.; Hoeft, M.; Karastergiou, A.; Kondratiev, V. I.; Kuper, G.; van Leeuwen, J.; McKay-Bukowski, D.; McKean, J. P.; Munk, H.; Orru, E.; Paas, H.; Pizzo, R.; Polatidis, A. G.; Scaife, A. M. M.; Sluman, J.; Tasse, C.; Toribio, M. C.; Vermeulen, R.; Zarka, P.

2015-08-01

Context. The Sun is an active source of radio emission that is often associated with energetic phenomena ranging from nanoflares to coronal mass ejections (CMEs). At low radio frequencies (<100 MHz), numerous millisecond duration radio bursts have been reported, such as radio spikes or solar S bursts (where S stands for short). To date, these have neither been studied extensively nor imaged because of the instrumental limitations of previous radio telescopes. Aims: Here, LOw Frequency ARray (LOFAR) observations were used to study the spectral and spatial characteristics of a multitude of S bursts, as well as their origin and possible emission mechanisms. Methods: We used 170 simultaneous tied-array beams for spectroscopy and imaging of S bursts. Since S bursts have short timescales and fine frequency structures, high cadence (~50 ms) tied-array images were used instead of standard interferometric imaging, that is currently limited to one image per second. Results: On 9 July 2013, over 3000 S bursts were observed over a time period of ~8 h. S bursts were found to appear as groups of short-lived (<1 s) and narrow-bandwidth (~2.5 MHz) features, the majority drifting at ~3.5 MHz s-1 and a wide range of circular polarisation degrees (2-8 times more polarised than the accompanying Type III bursts). Extrapolation of the photospheric magnetic field using the potential field source surface (PFSS) model suggests that S bursts are associated with a trans-equatorial loop system that connects an active region in the southern hemisphere to a bipolar region of plage in the northern hemisphere. Conclusions: We have identified polarised, short-lived solar radio bursts that have never been imaged before. They are observed at a height and frequency range where plasma emission is the dominant emission mechanism, however, they possess some of the characteristics of electron-cyclotron maser emission. A movie associated to Fig. 3 is available in electronic form at http://www.aanda.org

A new concept of imaging system: telescope windows

NASA Astrophysics Data System (ADS)

Bourgenot, Cyril; Cowie, Euan; Young, Laura; Love, Gordon; Girkin, John; Courtial, Johannes

2018-02-01

A Telescope window is a novel concept of transformation-optics consisting of an array of micro-telescopes, in our configuration, of a Galilean type. When the array is considered as one multifaceted device, it acts as a traditional Galilean telescope with distinctive and attractive properties such as compactness and modularity. Each lenslet, can in principle, be independently designed for a specific optical function. In this paper, we report on the design, manufacture and prototyping, by diamond precision machining, of 2 concepts of telescope windows, and discuss both their performances and limitations with a view to use them as potential low vision aid devices to support patients with macular degeneration.

Seven-panel solar wing deployment and on-orbit maneuvering analyses

NASA Astrophysics Data System (ADS)

Hwang, Earl

2005-05-01

BSS developed a new generation high power (~20kW) solar array to meet the customer demands. The high power solar array had the north and south solar wings of which designs were identical. Each side of the solar wing consists of three main conventional solar panels and the four-side panel swing-out new design. The fully deployed solar array surface area is 966 ft2. It was a quite challenging task to define the solar array's optimum design parameters and deployment scheme for such a huge solar array's successful deployment and on-orbit maneuvering. Hence, a deployable seven-flex-panel solar wing nonlinear math model and a fully deployed solar array/bus-payload math model were developed with the Dynamic Analysis and Design System (DADS) program codes utilizing the inherited and empirical data. Performing extensive parametric analyses with the math model, the optimum design parameters and the orbit maneuvering /deployment schemes were determined to meet all the design requirements, and for the successful solar wing deployment on-orbit.

Low-cost silicon solar array project environmental hail model for assessing risk to solar collectors

NASA Technical Reports Server (NTRS)

Gonzalez, C.

1977-01-01

The probability of solar arrays being struck by hailstones of various sizes as a function of geographic location and service life was assessed. The study complements parallel studies of solar array sensitivity to hail damage, the final objective being an estimate of the most cost effective level for solar array hail protection.

Prospects for gravitational wave astronomy with next generation large-scale pulsar timing arrays

NASA Astrophysics Data System (ADS)

Wang, Yan; Mohanty, Soumya D.

2018-02-01

Next generation radio telescopes, namely the Five-hundred-meter Aperture Spherical Telescope (FAST) and the Square Kilometer Array (SKA), will revolutionize the pulsar timing arrays (PTAs) based gravitational wave (GW) searches. We review some of the characteristics of FAST and SKA, and the resulting PTAs, that are pertinent to the detection of gravitational wave signals from individual supermassive black hole binaries.

Analysis of X-ray and EUV spectra of solar active regions

NASA Technical Reports Server (NTRS)

Strong, K. T.; Acton, L. W.

1979-01-01

Data acquired by two flights of an array of six Bragg crystal spectrometers on an Aerobee rocket to obtain high spatial and spectral resolution observations of various coronal features at soft X-ray wavelengths (9-23A) were analyzed. The various aspects of the analysis of the X-ray data are described. These observations were coordinated with observations from the experiments on the Apollo Telescope Mount and the various data sets were related to one another. The Appendices contain the published results, abstracts of papers, computer code descriptions and preprints of papers, all produced as a result of this research project.

KSC-99pp0350

NASA Image and Video Library

1999-03-26

In the Vertical Processing Facility, TRW technicians get ready to attach and deploy a solar panel array on the Chandra X-ray Observatory, which is sitting on a workstand. The panel is to the right. Formerly called the Advanced X-ray Astrophysics Facility, Chandra comprises three major elements: the spacecraft, the science instrument module (SIM), and the world's most powerful X-ray telescope. Chandra will allow scientists from around the world to see previously invisible black holes and high-temperature gas clouds, giving the observatory the potential to rewrite the books on the structure and evolution of our universe. Chandra is scheduled for launch July 9 aboard Space Shuttle Columbia, on mission STS-93

KSC-99pp0353

NASA Image and Video Library

1999-03-26

In the Vertical Processing Facility, a TRW technician checks the attachment of the solar panel array (out of sight to the right) to the Chandra X-ray Observatory, at left. Formerly called the Advanced X-ray Astrophysics Facility, Chandra comprises three major elements: the spacecraft, the science instrument module (SIM), and the world's most powerful X-ray telescope. Chandra will allow scientists from around the world to see previously invisible black holes and high-temperature gas clouds, giving the observatory the potential to rewrite the books on the structure and evolution of our universe. Chandra is scheduled for launch July 9 aboard Space Shuttle Columbia, on mission STS-93

Astronaut Kathryn Thornton on HST photographed by Electronic Still Camera

NASA Image and Video Library

1993-12-05

S61-E-011 (5 Dec 1993) --- This view of astronaut Kathryn C. Thornton working on the Hubble Space Telescope (HST) was photographed with an Electronic Still Camera (ESC), and down linked to ground controllers soon afterward. Thornton, anchored to the end of the Remote Manipulator System (RMS) arm, is installing the +V2 Solar Array Panel as a replacement for the original one removed earlier. Electronic still photography is a relatively new technology which provides the means for a handheld camera to electronically capture and digitize an image with resolution approaching film quality. The electronic still camera has flown as an experiment on several other shuttle missions.

Solar microwave bursts - A review

NASA Technical Reports Server (NTRS)

Kundu, M. R.; Vlahos, L.

1982-01-01

Observational and theoretical results on the physics of microwave bursts that occur in the solar atmosphere are reviewed. Special attention is given to the advances made in burst physics over the last few years with the great improvement in spatial and time resolution, especially with instruments like the NRAO three-element interferometer, the Westerbork Synthesis Radio Telescope, and more recently the Very Large Array. Observations made on the preflare build-up of an active region at centimeter wavelengths are reviewed. Three distinct phases in the evolution of cm bursts, namely the impulsive phase, the post-burst phase, and the gradual rise and fall, are discussed. Attention is also given to the flux density spectra of centimeter bursts. Descriptions are given of observations of fine structures with temporal resolution of 10-100 ms in the intensity profiles of cm-wavelength bursts. High spatial resolution observations are analyzed, with special reference to the one- and two-dimensional maps of cm burst sources.

KSC-2009-1129

NASA Image and Video Library

2009-01-13

CAPE CANAVERAL, Fla. -- Ball Aerospace and Technology workers conduct a light test on the solar array panels of NASA's Kepler spacecraft. A NASA Discovery mission, Kepler is specifically designed to survey our region of the Milky Way galaxy to discover hundreds of Earth-size and smaller planets in or near the habitable zone and determine how many of the billions of stars in our galaxy have such planets. Kepler will hunt for planets using a specialized one-meter diameter telescope called a photometer to measure the small changes in brightness caused by the transits. Results from this mission will allow us to place our solar system within the continuum of planetary systems in the Galaxy. After processing at Astrotech, Kepler will be carried to its launch pad at Cape Canaveral Air Force Station. NASA's planet-hunting Kepler mission is scheduled to launch no earlier than March 5 atop a United Launch Alliance Delta II rocket. Photo credit: NASA/Kim Shiflett

KSC-2009-1124

NASA Image and Video Library

2009-01-13

CAPE CANAVERAL, Fla. -- Lights are reflected on the solar array panels of NASA's Kepler spacecraft during illumination testing. A NASA Discovery mission, Kepler is specifically designed to survey our region of the Milky Way galaxy to discover hundreds of Earth-size and smaller planets in or near the habitable zone and determine how many of the billions of stars in our galaxy have such planets. Kepler will hunt for planets using a specialized one-meter diameter telescope called a photometer to measure the small changes in brightness caused by the transits. Results from this mission will allow us to place our solar system within the continuum of planetary systems in the Galaxy. After processing at Astrotech, Kepler will be carried to its launch pad at Cape Canaveral Air Force Station. NASA's planet-hunting Kepler mission is scheduled to launch no earlier than March 5 atop a United Launch Alliance Delta II rocket. Photo credit: NASA/Kim Shiflett

KSC-2009-1125

NASA Image and Video Library

2009-01-13

CAPE CANAVERAL, Fla. -- Ball Aerospace and Technology workers conduct a light test on the solar array panels of NASA's Kepler spacecraft. A NASA Discovery mission, Kepler is specifically designed to survey our region of the Milky Way galaxy to discover hundreds of Earth-size and smaller planets in or near the habitable zone and determine how many of the billions of stars in our galaxy have such planets. Kepler will hunt for planets using a specialized one-meter diameter telescope called a photometer to measure the small changes in brightness caused by the transits. Results from this mission will allow us to place our solar system within the continuum of planetary systems in the Galaxy. After processing at Astrotech, Kepler will be carried to its launch pad at Cape Canaveral Air Force Station. NASA's planet-hunting Kepler mission is scheduled to launch no earlier than March 5 atop a United Launch Alliance Delta II rocket. Photo credit: NASA/Kim Shiflett

KSC-2009-1126

NASA Image and Video Library

2009-01-13

CAPE CANAVERAL, Fla. -- Ball Aerospace and Technology workers conduct a light test on the solar array panels of NASA's Kepler spacecraft. A NASA Discovery mission, Kepler is specifically designed to survey our region of the Milky Way galaxy to discover hundreds of Earth-size and smaller planets in or near the habitable zone and determine how many of the billions of stars in our galaxy have such planets. Kepler will hunt for planets using a specialized one-meter diameter telescope called a photometer to measure the small changes in brightness caused by the transits. Results from this mission will allow us to place our solar system within the continuum of planetary systems in the Galaxy. After processing at Astrotech, Kepler will be carried to its launch pad at Cape Canaveral Air Force Station. NASA's planet-hunting Kepler mission is scheduled to launch no earlier than March 5 atop a United Launch Alliance Delta II rocket. Photo credit: NASA/Kim Shiflett

Vertical flows of supergranular and mesogranular scale observed on the sun with OSO 8

NASA Technical Reports Server (NTRS)

November, L. J.; Toomre, J.; Gebbie, K. B.; Simon, G. W.

1982-01-01

A program of observations was carried out in order to study the penetration of supergranular flows over a broad range of heights in the solar atmosphere. Steady Doppler velocities are determined from observations of a Si II spectral line using the Ultraviolet Spectrometer on the Orbiting Solar Observatory 8 (OSO 8) satellite and Fe I and Mg I lines with the diode-array instrument on the vacuum telescope at Sacramento Peak Observatory (SPO). The heights of formation of these spectral lines span about 1400 km or nearly 11 density scale heights from the photosphere to the middle chromosphere. Steady vertical flows on spatial scales typical of supergranulation and mesogranulation have been detected in the middle chromosphere with OSO 8. The patterns of intensity and steady velocity of granular scale are reproducible in successive data sets. The patterns appear to evolve slowly over the 9 hr period spanned by six orbits.

KSC-2009-1123

NASA Image and Video Library

2009-01-13

CAPE CANAVERAL, Fla. -- Ball Aerospace and Technology workers conduct a light test on the solar array panels of NASA's Kepler spacecraft. A NASA Discovery mission, Kepler is specifically designed to survey our region of the Milky Way galaxy to discover hundreds of Earth-size and smaller planets in or near the habitable zone and determine how many of the billions of stars in our galaxy have such planets. Kepler will hunt for planets using a specialized one-meter diameter telescope called a photometer to measure the small changes in brightness caused by the transits. Results from this mission will allow us to place our solar system within the continuum of planetary systems in the Galaxy. After processing at Astrotech, Kepler will be carried to its launch pad at Cape Canaveral Air Force Station. NASA's planet-hunting Kepler mission is scheduled to launch no earlier than March 5 atop a United Launch Alliance Delta II rocket. Photo credit: NASA/Kim Shiflett

Skylab 3,Skylab as the CM moves in for docking

NASA Image and Video Library

1973-07-28

SL3-114-1683 (28 July 1973) --- A close-up view of the Skylab space station photographed against an Earth background from the Skylab 3 Command and Service Modules (CSM) during station-keeping maneuvers prior to docking. Aboard the Command Module (CM) were astronauts Alan L. Bean, Owen K. Garriott and Jack R. Lousma, who remained with the Skylab Space Station in Earth orbit for 59 days. This picture was taken with a hand-held 70mm Hasselblad camera using a 100mm lens and SO-368 medium speed Ektachrome film. Note the one solar array system wing on the Orbital Workshop (OWS) which was successfully deployed during extravehicular activity (EVA) on the first manned Skylab flight. The parasol solar shield which was deployed by the Skylab 2 crew can be seen through the support struts of the Apollo Telescope Mount (ATM). Photo credit: NASA

Software design and code generation for the engineering graphical user interface of the ASTRI SST-2M prototype for the Cherenkov Telescope Array

NASA Astrophysics Data System (ADS)

Tanci, Claudio; Tosti, Gino; Antolini, Elisa; Gambini, Giorgio F.; Bruno, Pietro; Canestrari, Rodolfo; Conforti, Vito; Lombardi, Saverio; Russo, Federico; Sangiorgi, Pierluca; Scuderi, Salvatore

2016-08-01

ASTRI is an on-going project developed in the framework of the Cherenkov Telescope Array (CTA). An end- to-end prototype of a dual-mirror small-size telescope (SST-2M) has been installed at the INAF observing station on Mt. Etna, Italy. The next step is the development of the ASTRI mini-array composed of nine ASTRI SST-2M telescopes proposed to be installed at the CTA southern site. The ASTRI mini-array is a collaborative and international effort carried on by Italy, Brazil and South-Africa and led by the Italian National Institute of Astrophysics, INAF. To control the ASTRI telescopes, a specific ASTRI Mini-Array Software System (MASS) was designed using a scalable and distributed architecture to monitor all the hardware devices for the telescopes. Using code generation we built automatically from the ASTRI Interface Control Documents a set of communication libraries and extensive Graphical User Interfaces that provide full access to the capabilities offered by the telescope hardware subsystems for testing and maintenance. Leveraging these generated libraries and components we then implemented a human designed, integrated, Engineering GUI for MASS to perform the verification of the whole prototype and test shared services such as the alarms, configurations, control systems, and scientific on-line outcomes. In our experience the use of code generation dramatically reduced the amount of effort in development, integration and testing of the more basic software components and resulted in a fast software release life cycle. This approach could be valuable for the whole CTA project, characterized by a large diversity of hardware components.

Developing an Inflatable Solar Array

NASA Technical Reports Server (NTRS)

Malone, Patrick K.; Jankowski, Francis J.; Williams, Geoffery T.; Vendura, George J., Jr.

1992-01-01

Viewgraphs describing the development of an inflatable solar array as part of the Inflatable Torus Solar Array Technology (ITSAT) program are presented. Program phases, overall and subsystem designs, and array deployment are addressed.

Towards a flexible array control and operation framework for CTA

NASA Astrophysics Data System (ADS)

Birsin, E.; Colomé, J.; Hoffmann, D.; Koeppel, H.; Lamanna, G.; Le Flour, T.; Lopatin, A.; Lyard, E.; Melkumyan, D.; Oya, I.; Panazol, J.-L.; Schlenstedt, S.; Schmidt, T.; Schwanke, U.; Stegmann, C.; Walter, R.; Wegner, P.; CTA Consortium

2012-12-01

The Cherenkov Telescope Array (CTA) [1] will be the successor to current Imaging Atmospheric Cherenkov Telescopes (IACT) like H.E.S.S., MAGIC and VERITAS. CTA will improve in sensitivity by about an order of magnitude compared to the current generation of IACTs. The energy range will extend from well below 100 GeV to above 100 TeV. To accomplish these goals, CTA will consist of two arrays, one in each hemisphere, consisting of 50-80 telescopes and composed of three different telescope types with different mirror sizes. It will be the first open observatory for very high energy γ-ray astronomy. The Array Control working group of CTA is currently evaluating existing technologies which are best suited for a project like CTA. The considered solutions comprise the ALMA Common Software (ACS), the OPC Unified Architecture (OPC UA) and the Data Distribution Service (DDS) for bulk data transfer. The first applications, like an automatic observation scheduler and the control software for some prototype instrumentation have been developed.

Next-generation Event Horizon Telescope developments: new stations for enhanced imaging

NASA Astrophysics Data System (ADS)

Palumbo, Daniel; Johnson, Michael; Doeleman, Sheperd; Chael, Andrew; Bouman, Katherine

2018-01-01

The Event Horizon Telescope (EHT) is a multinational Very Long Baseline Interferometry (VLBI) network of dishes joined to resolve general relativistic behavior near a supermassive black hole. The imaging quality of the EHT is largely dependent upon the sensitivity and spatial frequency coverage of the many baselines between its constituent telescopes. The EHT already contains many highly sensitive dishes, including the crucial Atacama Large Millimeter/Submillimeter Array (ALMA), making it viable to add smaller, cheaper telescopes to the array, greatly improving future capabilities of the EHT. We develop tools for optimizing the positions of new dishes in planned arrays. We also explore the feasibility of adding small orbiting dishes to the EHT, and develop orbital optimization tools for space-based VLBI imaging. Unlike the Millimetron mission planned to be at L2, we specifically treat near-earth orbiters, and find rapid filling of spatial frequency coverage across a large range of baseline lengths. Finally, we demonstrate significant improvement in image quality when adding small dishes to planned arrays in simulated observations.

NASA Marshall Space Flight Center Solar Observatory report, January - June 1990

NASA Technical Reports Server (NTRS)

Smith, James E.

1990-01-01

A description of the NASA Marshall Space Flight Center's Solar Vector Magnetograph Facility is presented and a summary of its observations and data reduction is given. The systems that make up the facility are a magnetograph telescope, an H alpha telescope, a Questar telescope, and a computer code. The data are represented by longitudinal contours with azimuth plots.

NASA Marshall Space Flight Center solar observatory

NASA Technical Reports Server (NTRS)

Smith, James E.

1988-01-01

A description is provided of the NASA Marshall Space Flight Center's Solar Vector Magnetograph Facility and a summary is given of its observations and data reduction during Jan. to Mar. 1988. The systems that make up the facility are a magnetograph telescope, an H-alpha telescope, a Questar telescope, and a computer center. The data are represented by longitudinal contours with azimuth plots.

Goddard Space Flight Center solar array missions, requirements and directions

NASA Technical Reports Server (NTRS)

Gaddy, Edward; Day, John

1994-01-01

The Goddard Space Flight Center (GSFC) develops and operates a wide variety of spacecraft for conducting NASA's communications, space science, and earth science missions. Some are 'in house' spacecraft for which the GSFC builds the spacecraft and performs all solar array design, analysis, integration, and test. Others are 'out of house' spacecraft for which an aerospace contractor builds the spacecraft and develops the solar array under direction from GSFC. The experience of developing flight solar arrays for numerous GSFC 'in house' and 'out of house' spacecraft has resulted in an understanding of solar array requirements for many different applications. This presentation will review those solar array requirements that are common to most GSFC spacecraft. Solar array technologies will be discussed that are currently under development and that could be useful to future GSFC spacecraft.

SKA aperture array verification system: electromagnetic modeling and beam pattern measurements using a micro UAV

NASA Astrophysics Data System (ADS)

de Lera Acedo, E.; Bolli, P.; Paonessa, F.; Virone, G.; Colin-Beltran, E.; Razavi-Ghods, N.; Aicardi, I.; Lingua, A.; Maschio, P.; Monari, J.; Naldi, G.; Piras, M.; Pupillo, G.

2018-03-01

In this paper we present the electromagnetic modeling and beam pattern measurements of a 16-elements ultra wideband sparse random test array for the low frequency instrument of the Square Kilometer Array telescope. We discuss the importance of a small array test platform for the development of technologies and techniques towards the final telescope, highlighting the most relevant aspects of its design. We also describe the electromagnetic simulations and modeling work as well as the embedded-element and array pattern measurements using an Unmanned Aerial Vehicle system. The latter are helpful both for the validation of the models and the design as well as for the future instrumental calibration of the telescope thanks to the stable, accurate and strong radio frequency signal transmitted by the UAV. At this stage of the design, these measurements have shown a general agreement between experimental results and numerical data and have revealed the localized effect of un-calibrated cable lengths in the inner side-lobes of the array pattern.

SMEX-Lite Modular Solar Array Architecture

NASA Technical Reports Server (NTRS)

Lyons, John W.; Day, John (Technical Monitor)

2002-01-01

The NASA Small Explorer (SMEX) missions have typically had three years between mission definition and launch. This short schedule has posed significant challenges with respect to solar array design and procurement. Typically, the solar panel geometry is frozen prior to going out with a procurement. However, with the SMEX schedule, it has been virtually impossible to freeze the geometry in time to avoid scheduling problems with integrating the solar panels to the spacecraft. A modular solar array architecture was developed to alleviate this problem. This approach involves procuring sufficient modules for multiple missions and assembling the modules onto a solar array framework that is unique to each mission. The modular approach removes the solar array from the critical path of the SMEX integration and testing schedule. It also reduces the cost per unit area of the solar arrays and facilitates the inclusion of experiments involving new solar cell or panel technologies in the SMEX missions.

Ionospheric Caustics in Solar Radio Observations

NASA Astrophysics Data System (ADS)

Koval, A.; Chen, Y.; Stanislavsky, A.

2016-12-01

The Earth ionosphere possesses by natural focusing and defocusing effects on radio waves due to presence of variable ionospheric irregularities which could act like convergent and divergent lenses on incident radiation. In particular, the focusing of emission from the Sun was firstly detected on the Nançay Decameter Array dynamic spectra in the 1980s. On time-frequency spectrograms the intensity variations form specific structures different from well-known solar radio bursts and clearly distinguishing on a background of solar radiation. Such structures have been identified as ionospheric caustics (ICs) and considered to be the result of radio waves refraction on medium scale travelling ionospheric disturbances (MSTIDs). Although nowadays the ICs are registered by different radio observatories due to augmentation of low-frequency radio telescopes, the most recent papers devoted to ICs in solar radio records date back to the 1980s. In this study, we revisit the ICs issue with some new results by conducting a statistical analysis of occurrence rate of ICs in solar dynamic spectra in meter-decameter wavelength range for long continuous period (15 years). The seasonal variations in ICs appearance have been found for the first time. Besides, we report the possible solar cycle dependence of ICs emergence. The radio waves propagation in the ionosphere comprising MSTIDs will be considered. The present research renews the subject of ICs in the low-frequency solar radio astronomy after about 35-year letup.

Solar Eclipses Observed from Antarctica

NASA Astrophysics Data System (ADS)

Pasachoff, Jay M.

2013-01-01

Aspects of the solar corona are still best observed during totality of solar eclipses, and other high-resolution observations of coronal active regions can be observed with radio telescopes by differentiation of occultation observations, as we did with the Jansky Very Large Array for the annular solar eclipse of 2012 May 20 in the US. Totality crossing Antarctica included the eclipse of 2003 November 23, and will next occur on 2021 December 4; annularity crossing Antarctica included the eclipse of 2008 February 7, and will next occur on 2014 April 29. Partial phases as high as 87% coverage were visible and were imaged in Antarctica on 2011 November 25, and in addition to partial phases of the total and annular eclipses listed above, partial phases were visible in Antarctica on 2001 July 2011, 2002 December 4, 2004 April 19, 2006 September 22, 2007 September 11, and 2009 January 26, and will be visible on 2015 September 13, 2016 September 1, 2017 February 26, 2018 February 15, and 2020 December 14. On behalf of the Working Group on Solar Eclipses of the IAU, the poster showed the solar eclipses visible from Antarctica and this article shows a subset (see www.eclipses.info for the full set). A variety of investigations of the Sun and of the response of the terrestrial atmosphere and ionosphere to the abrupt solar cutoff can be carried out at the future eclipses, making the Antarctic observations scientifically useful.

Space Shuttle Projects

NASA Image and Video Library

2002-03-03

The Hubble Space Telescope (HST), with its normal routine temporarily interrupted, is about to be captured by the Space Shuttle Columbia prior to a week of servicing and upgrading by the STS-109 crew. The telescope was captured by the shuttle's Remote Manipulator System (RMS) robotic arm and secured on a work stand in Columbia's payload bay where 4 of the 7-member crew performed 5 space walks completing system upgrades to the HST. Included in those upgrades were: The replacement of the solar array panels; replacement of the power control unit (PCU); replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS); and installation of the experimental cooling system for the Hubble's Near-Infrared Camera and Multi-object Spectrometer (NICMOS), which had been dormant since January 1999 when its original coolant ran out. The Marshall Space Flight Center had the responsibility for the design, development, and construction of the the HST, which is the most complex and sensitive optical telescope ever made, to study the cosmos from a low-Earth orbit. Launched March 1, 2002, the STS-109 HST servicing mission lasted 10 days, 22 hours, and 11 minutes. It was the 108th flight overall in NASA's Space Shuttle Program.

Space Shuttle Projects

NASA Image and Video Library

2002-03-05

STS-109 Astronauts Michael J. Massimino and James H. Newman were making their second extravehicular activity (EVA) of their mission when astronaut Massimino, mission specialist, peered into Columbia's crew cabin during a brief break from work on the Hubble Space Telescope (HST). The HST is latched down just a few feet behind him in Columbia's cargo bay. The Space Shuttle Columbia STS-109 mission lifted off March 1, 2002 with goals of repairing and upgrading the Hubble Space Telescope (HST). STS-109 upgrades to the HST included: replacement of the solar array panels; replacement of the power control unit (PCU); replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS); and installation of the experimental cooling system for the Hubble's Near-Infrared Camera and Multi-object Spectrometer (NICMOS), which had been dormant since January 1999 when its original coolant ran out. The Marshall Space Flight Center in Huntsville, Alabama had the responsibility for the design, development, and construction of the HST, which is the most powerful and sophisticated telescope ever built. Lasting 10 days, 22 hours, and 11 minutes, the STS-109 mission was the 108th flight overall in NASA's Space Shuttle Program.

STS-109 Astronaut Michael J. Massimino Peers Into Window of Shuttle During EVA

NASA Technical Reports Server (NTRS)

2002-01-01

STS-109 Astronauts Michael J. Massimino and James H. Newman were making their second extravehicular activity (EVA) of their mission when astronaut Massimino, mission specialist, peered into Columbia's crew cabin during a brief break from work on the Hubble Space Telescope (HST). The HST is latched down just a few feet behind him in Columbia's cargo bay. The Space Shuttle Columbia STS-109 mission lifted off March 1, 2002 with goals of repairing and upgrading the Hubble Space Telescope (HST). STS-109 upgrades to the HST included: replacement of the solar array panels; replacement of the power control unit (PCU); replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS); and installation of the experimental cooling system for the Hubble's Near-Infrared Camera and Multi-object Spectrometer (NICMOS), which had been dormant since January 1999 when its original coolant ran out. The Marshall Space Flight Center in Huntsville, Alabama had the responsibility for the design, development, and construction of the HST, which is the most powerful and sophisticated telescope ever built. Lasting 10 days, 22 hours, and 11 minutes, the STS-109 mission was the 108th flight overall in NASA's Space Shuttle Program.

The control system of the 12-m medium-size telescope prototype: a test-ground for the CTA array control

NASA Astrophysics Data System (ADS)

Oya, I.; Anguner, E. A.; Behera, B.; Birsin, E.; Fuessling, M.; Lindemann, R.; Melkumyan, D.; Schlenstedt, S.; Schmidt, T.; Schwanke, U.; Sternberger, R.; Wegner, P.; Wiesand, S.

2014-07-01

The Cherenkov Telescope Array (CTA) will be the next generation ground-based very-high energy -ray observatory. CTA will consist of two arrays: one in the Northern hemisphere composed of about 20 telescopes, and the other one in the Southern hemisphere composed of about 100 telescopes, both arrays containing telescopes of different sizes and types and in addition numerous auxiliary devices. In order to provide a test-ground for the CTA array control, the steering software of the 12-m medium size telescope (MST) prototype deployed in Berlin has been implemented using the tools and design concepts under consideration to be used for the control of the CTA array. The prototype control system is implemented based on the Atacama Large Millimeter/submillimeter Array (ALMA) Common Software (ACS) control middleware, with components implemented in Java, C++ and Python. The interfacing to the hardware is standardized via the Object Linking and Embedding for Process Control Unified Architecture (OPC UA). In order to access the OPC UA servers from the ACS framework in a common way, a library has been developed that allows to tie the OPC UA server nodes, methods and events to the equivalents in ACS components. The front-end of the archive system is able to identify the deployed components and to perform the sampling of the monitoring points of each component following time and value change triggers according to the selected configurations. The back-end of the archive system of the prototype is composed by two different databases: MySQL and MongoDB. MySQL has been selected as storage of the system configurations, while MongoDB is used to have an efficient storage of device monitoring data, CCD images, logging and alarm information. In this contribution, the details and conclusions on the implementation of the control software of the MST prototype are presented.

Optical and thermal design of 1.5-m aperture solar UV visible and IR observing telescope for Solar-C mission

NASA Astrophysics Data System (ADS)

Suematsu, Y.; Katsukawa, Y.; Shimizu, T.; Ichimoto, K.; Horiuchi, T.; Matsumoto, Y.; Takeyama, N.

2017-11-01

The next Japanese solar mission, SOLAR-C, which has been envisaged after successful science operation of Hinode (SOLAR-B) mission, is perusing two plans: plan-A and plan-B, and under extensive study from science objectives as well as engineering point of view. The plan-A aims at performing out-of-ecliptic observations for investigating, with helioseismic approach, internal structure and dynamo mechanisms of the Sun. It also explores polar regions where fast solar wind is believed to originate. A baseline orbit for plan-A is a circular orbit of 1 AU distance from the Sun with its inclination at around or greater than 40 degrees. The plan-B aims to study small-scale plasma processes and structures in the solar atmosphere which attract researchers' growing interest, followed by many Hinode discoveries [1], for understanding fully dynamism and magnetic nature of the atmosphere. With plan-B, high-angular-resolution investigation of the entire solar atmosphere (from the photosphere to the corona, including their interface layers, i.e., chromosphere and transition region) is to be performed with enhanced spectroscopic and spectro-polarimetric capability as compared with Hinode, together with enhanced sensitivity towards ultra-violet wavelengths. The orbit of plan-B is either a solar synchronous polar orbit of altitude around 600 km or a geosynchronous orbit to ensure continuous solar observations. After the decision of any one of the two plans, the SOLAR-C will be proposed for launch in mid-2010s. In this paper, we will present a basic design of one of major planned instrumental payload for the plan-B: the Solar Ultra-violet Visible and near IR observing Telescope (hereafter referred to as SUVIT). The basic concept in designing the SUVIT is to utilize as much as possible a heritage of successful telescope of the Solar Optical Telescope (SOT) aboard Hinode [2]. Major differences of SUVIT from SOT are the three times larger aperture of 1.5 m, which enables to collect one order of magnitude more photons than SOT, relatively shorter telescope length of 2.8 m to accommodate a launcher's nosecone size for possible dual-satellite-launch configuration, and much wider observing wavelength from UV (down to 250 nm) through near IR (up to 1100 nm). The large aperture is essentially important to attain scientific goals of the plan-B, especially for accurate diagnostics of the dynamic solar chromosphere as revealed by Hinode, although this make it difficult to design the telescope because of ten times more solar heat load introduced into the telescope. The SUVIT consists of two optically separable components; the telescope assembly (TA) and an accompanying focal plane package equipped with filtergraphs and spectrographs. Opto-mechanical and -thermal performance of the TA is crucial to attain high-quality solar observations and here we present a status of feasible study in its optical and thermal designing for diffraction-limited performance at visible wavelength in a reasonably wide field of view.

Atomic Oxygen Durability Testing of an International Space Station Solar Array Validation Coupon

NASA Technical Reports Server (NTRS)

Forkapa, Mark J.; Stidham, Curtis; Banks, Bruce A.; Rutledge, Sharon K.; Ma, David H.; Sechkar, Edward A.

1996-01-01

An International Space Station solar array validation coupon was exposed in a directed atomic oxygen beam for space environment durability testing at the NASA Lewis Research Center. Exposure to atomic oxygen and intermittent tensioning of the solar array were conducted to verify the solar array#s durability to low Earth orbital atomic oxygen and to the docking threat of plume loading both of which are anticipated over its expected mission life of fifteen years. The validation coupon was mounted on a specially designed rotisserie. The rotisserie mounting enabled the solar and anti-solar facing side of the array to be exposed to directed atomic oxygen in a sweeping arrival process replicating space exposure. The rotisserie mounting also enabled tensioning, in order to examine the durability of the array and its hinge to simulated plume loads. Flash testing to verify electrical performance of the solar array was performed with a solar simulator before and after the exposure to atomic oxygen and tensile loading. Results of the flash testing indicated little or no degradation in the solar array#s performance. Photographs were also taken of the array before and after the durability testing and are included along with comparisons and discussions in this report. The amount of atomic oxygen damage appeared minor with the exception of a very few isolated defects. There were also no indications that the simulated plume loadings had weakened or damaged the array, even though there was some erosion of Kapton due to atomic oxygen attack. Based on the results of this testing, it is apparent that the International Space Station#s solar arrays should survive the low Earth orbital atomic oxygen environment and docking threats which are anticipated over its expected mission life.

STS-109 Onboard Photo of Extra-Vehicular Activity (EVA)

NASA Technical Reports Server (NTRS)

2002-01-01

This is an onboard photo of the Hubble Space Telescope (HST) power control unit (PCU), the heart of the HST's power system. STS-109 payload commander John M. Grunsfeld, joined by Astronaut Richard M. Lirnehan, turned off the telescope in order to replace its PCU while participating in the third of five spacewalks dedicated to servicing and upgrading the HST. Other upgrades performed were: replacement of the solar array panels; replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS); and installation of the experimental cooling system for the Hubble's Near-Infrared Camera and Multi-Object Spectrometer (NICMOS), which had been dormant since January 1999 when its original coolant ran out. The telescope was captured and secured on a work stand in Columbia's payload bay using Columbia's robotic arm, where crew members completed the system upgrades. The Marshall Space Flight Center had the responsibility for the design, development, and construction of the HST, which is the most complex and sensitive optical telescope ever made, to study the cosmos from a low-Earth orbit. The HST detects objects 25 times fainter than the dimmest objects seen from Earth and provides astronomers with an observable universe 250 times larger than is visible from ground-based telescopes, perhaps as far away as 14 billion light-years. Launched March 1, 2002 the STS-109 HST servicing mission lasted 10 days, 22 hours, and 11 minutes. It was the 108th flight overall in NASA's Space Shuttle Program.

Space Shuttle Projects

NASA Image and Video Library

2002-03-01

This is an onboard photo of the Hubble Space Telescope (HST) power control unit (PCU), the heart of the HST's power system. STS-109 payload commander John M. Grunsfeld, joined by Astronaut Richard M. Lirnehan, turned off the telescope in order to replace its PCU while participating in the third of five spacewalks dedicated to servicing and upgrading the HST. Other upgrades performed were: replacement of the solar array panels; replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS); and installation of the experimental cooling system for the Hubble's Near-Infrared Camera and Multi-Object Spectrometer (NICMOS), which had been dormant since January 1999 when its original coolant ran out. The telescope was captured and secured on a work stand in Columbia's payload bay using Columbia's robotic arm, where crew members completed the system upgrades. The Marshall Space Flight Center had the responsibility for the design, development, and construction of the HST, which is the most complex and sensitive optical telescope ever made, to study the cosmos from a low-Earth orbit. The HST detects objects 25 times fainter than the dimmest objects seen from Earth and provides astronomers with an observable universe 250 times larger than is visible from ground-based telescopes, perhaps as far away as 14 billion light-years. Launched March 1, 2002 the STS-109 HST servicing mission lasted 10 days, 22 hours, and 11 minutes. It was the 108th flight overall in NASA's Space Shuttle Program.

The Advanced Gamma-ray Imaging System (AGIS): Topological Array Trigger

NASA Astrophysics Data System (ADS)

Smith, Andrew W.

2010-03-01

AGIS is a concept for the next-generation ground-based gamma-ray observatory. It will be an array of 36 imaging atmospheric Cherenkov telescopes (IACTs) sensitive in the energy range from 50 GeV to 200 TeV. The required improvements in sensitivity, angular resolution, and reliability of operation relative to the present generation instruments imposes demanding technological and cost requirements on the design of the telescopes and on the triggering and readout systems for AGIS. To maximize the capabilities of large arrays of IACTs with a low energy threshold, a wide field of view and a low background rate, a sophisticated array trigger is required. We outline the status of the development of a stereoscopic array trigger that calculates image parameters and correlates them across a subset of telescopes. Field Programmable Gate Arrays (FPGAs) implement the real-time pattern recognition to suppress cosmic rays and night-sky background events. A proof of principle system is being developed to run at camera trigger rates up to 10MHz and array-level rates up to 10kHz.

First upper limits on the radar cross section of cosmic-ray induced extensive air showers

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

Abbasi, R. U.; Abe, M.; Abou Bakr Othman, M.

TARA (Telescope Array Radar) is a cosmic ray radar detection experiment colocated with Telescope Array, the conventional surface scintillation detector (SD) and fluorescence telescope detector (FD) near Delta, Utah, U.S.A. Furthermore, the TARA detector combines a 40 kW, 54.1 MHz VHF transmitter and high-gain transmitting antenna which broadcasts the radar carrier over the SD array and within the FD field of view, towards a 250 MS/s DAQ receiver. TARA has been collecting data since 2013 with the primary goal of observing the radar signatures of extensive air showers (EAS). Simulations indicate that echoes are expected to be short in durationmore » (~10 µs) and exhibit rapidly changing frequency, with rates on the order 1 MHz/µs. The EAS radar cross-section (RCS) is currently unknown although it is the subject of over 70 years of speculation. One novel signal search technique is described in which the expected radar echo of a particular air shower is used as a matched filter template and compared to waveforms obtained by triggering the radar DAQ using the Telescope Array fluorescence detector. No evidence for the scattering of radio frequency radiation by EAS is obtained to date. Finally, we report the first quantitative RCS upper limits using EAS that triggered the Telescope Array Fluorescence Detector.« less

First upper limits on the radar cross section of cosmic-ray induced extensive air showers

DOE PAGES

Abbasi, R. U.; Abe, M.; Abou Bakr Othman, M.; ...

2016-11-19

TARA (Telescope Array Radar) is a cosmic ray radar detection experiment colocated with Telescope Array, the conventional surface scintillation detector (SD) and fluorescence telescope detector (FD) near Delta, Utah, U.S.A. Furthermore, the TARA detector combines a 40 kW, 54.1 MHz VHF transmitter and high-gain transmitting antenna which broadcasts the radar carrier over the SD array and within the FD field of view, towards a 250 MS/s DAQ receiver. TARA has been collecting data since 2013 with the primary goal of observing the radar signatures of extensive air showers (EAS). Simulations indicate that echoes are expected to be short in durationmore » (~10 µs) and exhibit rapidly changing frequency, with rates on the order 1 MHz/µs. The EAS radar cross-section (RCS) is currently unknown although it is the subject of over 70 years of speculation. One novel signal search technique is described in which the expected radar echo of a particular air shower is used as a matched filter template and compared to waveforms obtained by triggering the radar DAQ using the Telescope Array fluorescence detector. No evidence for the scattering of radio frequency radiation by EAS is obtained to date. Finally, we report the first quantitative RCS upper limits using EAS that triggered the Telescope Array Fluorescence Detector.« less

The Implementation of Advanced Solar Array Technology in Future NASA Missions

NASA Technical Reports Server (NTRS)

Piszczor, Michael F.; Kerslake, Thomas W.; Hoffman, David J.; White, Steve; Douglas, Mark; Spence, Brian; Jones, P. Alan

2003-01-01

Advanced solar array technology is expected to be critical in achieving the mission goals on many future NASA space flight programs. Current PV cell development programs offer significant potential and performance improvements. However, in order to achieve the performance improvements promised by these devices, new solar array structures must be designed and developed to accommodate these new PV cell technologies. This paper will address the use of advanced solar array technology in future NASA space missions and specifically look at how newer solar cell technologies impact solar array designs and overall power system performance.

Imaging interplanetary CMEs at radio frequency from solar polar orbit

NASA Astrophysics Data System (ADS)

Wu, Ji; Sun, Weiying; Zheng, Jianhua; Zhang, Cheng; Liu, Hao; Yan, Jingye; Wang, Chi; Wang, Chuanbing; Wang, Shui

2011-09-01

Coronal mass ejections (CMEs) represent a great concentration of mass and energy input into the lower corona. They have come to be recognized as the major driver of physical conditions change in the Sun-Earth system. Consequently, observations of CMEs are important for understanding and ultimately predicting space weather conditions. This paper discusses a proposed mission, the Solar Polar Orbit Radio Telescope (SPORT) mission, which will observe the propagation of interplanetary CMEs to distances of near 0.35 AU from the Sun. The orbit of SPORT is an elliptical solar polar orbit. The inclination angle between the orbit and ecliptic plane should be about 90°. The main payload on board SPORT will be an imaging radiometer working at the meter wavelength band (radio telescope), which can follow the propagation of interplanetary CMEs. The images that are obtained by the radio telescope embody the brightness temperature of the objectives. Due to the very large size required for the antenna aperture of the radio telescope, we adopt interferometric imaging technology to reduce it. Interferometric imaging technology is based on indirect spatial frequency domain measurements plus Fourier transformation. The SPORT spacecraft will also be equipped with a set of optical and in situ measurement instruments such as a EUV solar telescope, a solar wind ion instrument, an energetic particle detector, a magnetometer, a wave detector and a solar radio burst spectrometer.

View of the Skylab 1 space station cluster from the Skylab 2 Command Module

NASA Image and Video Library

1973-05-25

S73-26738 (25 May 1973) --- A close-up view of the Skylab 1 space station cluster can be seen in this reproduction taken from a color television transmission made by a TV camera aboard the Skylab 2 Command Module during its ?fly-around? inspection of the cluster. The numbers across the top of the picture indicate the Skylab 1 ground lapse time. Note the missing portion of the micrometeoroid shield on the Orbital Workshop. The shield area was reported to be solid gold by the Skylab 2 crewmen. A cable appears to be wrapped around the damaged OWS solar array system wing. The crewmen reported that the other OWS solar panel was completely gone, with only tubes and wiring sticking out. One of the discone antennas extends out form the Airlock Module. The Multiple Docking Adapter is in the lower left corner of the picture. A portion of a solar panel on the Apollo Telescope Mount is visible at the bottom and at the left edge. In their ?fly around? inspection the crewmen noted that portions of the micrometeoroid shield had slid back underneath the OWS solar wing. Photo credit: NASA

The control, monitor, and alarm system for the ICT equipment of the ASTRI SST-2M telescope prototype for the Cherenkov Telescope Array

NASA Astrophysics Data System (ADS)

Gianotti, Fulvio; Fioretti, Valentina; Tanci, Claudio; Conforti, Vito; Tacchini, Alessandro; Leto, Giuseppe; Gallozzi, Stefano; Bulgarelli, Andrea; Trifoglio, Massimo; Malaguti, Giuseppe; Zoli, Andrea

2014-07-01

ASTRI is an Italian flagship project whose first goal is the realization of an end-to-end telescope prototype, named ASTRI SST-2M, for the Cherenkov Telescope Array (CTA). The prototype will be installed in Italy during Fall 2014. A second goal will be the realization of the ASTRI/CTA mini-array which will be composed of seven SST-2M telescopes placed at the CTA Southern Site. The Information and Communication Technology (ICT) equipment necessary to drive the infrastructure for the ASTRI SST-2M prototype is being designed as a complete and stand-alone computer center. The design goal is to obtain basic ICT equipment that might be scaled, with a low level of redundancy, for the ASTRI/CTA mini-array, taking into account the necessary control, monitor and alarm system requirements. The ICT equipment envisaged at the Serra La Nave observing station in Italy, where the ASTRI SST-2M telescope prototype will operate, includes computers, servers and workstations, network devices, an uninterruptable power supply system, and air conditioning systems. Suitable hardware and software tools will allow the parameters related to the behavior and health of each item of equipment to be controlled and monitored. This paper presents the proposed architecture and technical solutions that integrate the ICT equipment in the framework of the Observatory Control System package of the ASTRI/CTA Mini- Array Software System, MASS, to allow their local and remote control and monitoring. An end-toend test case using an Internet Protocol thermometer is reported in detail.

The SKA1 LOW telescope: system architecture and design performance

NASA Astrophysics Data System (ADS)

Waterson, Mark F.; Labate, Maria Grazia; Schnetler, Hermine; Wagg, Jeff; Turner, Wallace; Dewdney, Peter

2016-07-01

The SKA1-LOW radio telescope will be a low-frequency (50-350 MHz) aperture array located in Western Australia. Its scientific objectives will prioritize studies of the Epoch of Reionization and pulsar physics. Development of the telescope has been allocated to consortia responsible for the aperture array front end, timing distribution, signal and data transport, correlation and beamforming signal processors, infrastructure, monitor and control systems, and science data processing. This paper will describe the system architectural design and key performance parameters of the telescope and summarize the high-level sub-system designs of the consortia.

Impacts on Hubble Space Telescope solar arrays: discrimination between natural and man-made particles.

NASA Astrophysics Data System (ADS)

Kearsley, A. T.; Drolshagen, G.; McDonnell, J. A. M.; Mandeville, J.-C.; Moussi, A.

A Post-Flight Investigation was initiated by the European Space Agency to analyze impact fluxes on solar arrays of the Hubble Space Telescope (HST), exposed to space for 8.25 years at approximately 600 km altitude. The solar cells were deployed during servicing mission SM-1 (December 1993), and retrieved by shuttle orbiter Columbia in March 2002 (SM-3B). A sub-panel of 2 m2 was cut from the --V2 wing and cells were selected for in-depth analysis. Twelve cells (9.6x10-3 m2) were surveyed for flux of all craters of sizes greater than 5 microns Dco; six at the NHM, and six at ONERA. Cumulative flux plots reveal slightly greater abundance of very small craters than in a comparable survey of SM-1 cells. Analytical scanning electron microscopy was used to locate impact features and to analyse residues at the NHM. 103 features of 3 -- 4000 micron conchoidal detachment diameter (Dco) were located on a total of 17 solar cells. 78 features show identifiable residue: 36 are Space Debris impacts and 42 Micrometeoroid impacts. Of the remaining 25: 4 contain residue of ambiguous origin, 1 is a minor manufacturing flaw, 1 is obscured by contamination, and 19 are unresolved, lacking recognizable residue. Space debris impacts on the SM-3B cells are all less than 80 microns Dco, dominated by Al- rich residue, probably of solid rocket motor origin, some may be unburnt fuel. Three craters may be sodium metal droplet impacts. No residues from paint pigment, aluminium or ferrous alloys, or copper- and tin-bearing metal were found. All craters larger than 100 microns are of micrometeoroid origin, or unresolved. Most residues are magnesium-iron silicate or iron sulfide. A few craters show vesicular Mg, S, Fe and Ni residue. A single Fe Ni metal residue was found, as well as enigmatic Mg- and S-bearing residues, all considered of micrometeoroid origin. A few Fe-, O- and C-bearing residues were classified as of ambiguous origin. The quality and quantity of residue is clearly linked to the crater pit morphology, with oval pit features containing more identifiable residue, perhaps due to lower peak shock pressures experienced in these oblique-incidence impacts.

NASA Marshall Space Flight Center Solar Observatory report, October - December 1990

NASA Technical Reports Server (NTRS)

Smith, James E.

1991-01-01

A description of the NASA Marshall Space Flight Center's Solar Vector Magnetograph Facility is provided, and a summary of its observations and data reduction during Oct. - Dec. 1990 is presented. The systems that make up the facility are a magnetograph telescope, and H-alpha telescope, a Questar telescope, and a computer code. The data are represented by longitudinal contours with azimuth plots.

NASA Marshall Space Flight Center solar observatory report, January - December 1987

NASA Technical Reports Server (NTRS)

Smith, James E.

1989-01-01

This report provides a description of the NASA Marshall Space Flight Center's Solar Vector Magnetograph Facility and gives a summary of its observations and data reduction during January to December 1987. The systems that make up the facility are a magnetograph telescope, an H-alpha telescope, a Questar telescope, and a computer code. The data are represented by longitudinal contours with azimuth plots.

NASA Marshall Space Flight Center Solar Observatory report, July - September 1990

NASA Technical Reports Server (NTRS)

Smith, James E.

1991-01-01

A description of the NASA Marshall Space Flight C nter's Solar Vector Magnetograph Facility is provided and gives a summary of its observations and data reduction during Jul. - Sep. 1990. The systems that make up the facility are a magnetograph telescope, an H-alpha telescope, a Questar telescope, and a computer code. The data are represented by longitudinal contours with azimuth plots.

NASA Marshall Space Flight Center solar observatory report, January to December 1989

NASA Technical Reports Server (NTRS)

Smith, James E.

1990-01-01

A description is provided of the NASA-Marshall's Solar Vector Magnetograph Facility and a summary of its observations and data reduction during January to December 1989 is given. The systems that make up the facility are a magnetograph telescope, and H-alpha telescope, a Questar telescope, and a computer code. The data are represented by longitudinal contours with azimuth plots.

The software system for the Control and Data Acquisition for the Cherenkov Telescope Array

NASA Astrophysics Data System (ADS)

Wegner, P.; FüBling, M.; Oya, I.; Hagge, L.; Schwanke, U.; Schwarz, J.; Tosti, G.; Conforti, V.; Lyard, E.; Walter, R.; Oliveira Antonino, P.; Morgenstern, A.

2016-10-01

The Cherenkov Telescope Array (CTA), as the next generation ground-based very high-energy gamma-ray observatory, is defining new areas beyond those related to physics. It is also creating new demands on the control and data acquisition system. CTA will consist of two installations, one in each hemisphere, containing tens of telescopes of different sizes. The ACTL (array control and data acquisition) system will consist of the hardware and software that is necessary to control and monitor the CTA array, as well as to time-stamp, read-out, filter and store the scientific data at aggregated rates of a few GB/s. The ACTL system must implement a flexible software architecture to permit the simultaneous automatic operation of multiple sub-arrays of telescopes with a minimum personnel effort on site. In addition ACTL must be able to modify the observation schedule on timescales of a few tens of seconds, to account for changing environmental conditions or to prioritize incoming scientific alerts from time-critical transient phenomena such as gamma-ray bursts. This contribution summarizes the status of the development of the software architecture and the main design choices and plans.

The New NASA-STD-4005 and NASA-HDBK-4006, Essentials for Direct-Drive Solar Electric Propulsion

NASA Technical Reports Server (NTRS)

Ferguson, Dale C.

2007-01-01

High voltage solar arrays are necessary for direct-drive solar electric propulsion, which has many advantages, including simplicity and high efficiency. Even when direct-drive is not used, the use of high voltage solar arrays leads to power transmission and conversion efficiencies in electric propulsion Power Management and Distribution. Nevertheless, high voltage solar arrays may lead to temporary power disruptions, through the so-called primary electrostatic discharges, and may permanently damage arrays, through the so-called permanent sustained discharges between array strings. Design guidance is needed to prevent these solar array discharges, and to prevent high power drains through coupling between the electric propulsion devices and the high voltage solar arrays. While most electric propulsion systems may operate outside of Low Earth Orbit, the plasmas produced by their thrusters may interact with the high voltage solar arrays in many ways similarly to Low Earth Orbit plasmas. A brief description of previous experiences with high voltage electric propulsion systems will be given in this paper. There are two new official NASA documents available free through the NASA Standards website to help in designing and testing high voltage solar arrays for electric propulsion. They are NASA-STD-4005, the Low Earth Orbit Spacecraft Charging Design Standard, and NASA-HDBK-4006, the Low Earth Orbit Spacecraft Charging Design Handbook. Taken together, they can both educate the high voltage array designer in the engineering and science of spacecraft charging in the presence of dense plasmas and provide techniques for designing and testing high voltage solar arrays to prevent electrical discharges and power drains.

High-resolution VLBA imaging of the radio source Sgr A* at the Galactic Centre

NASA Technical Reports Server (NTRS)

Lo, K. Y.; Backer, D. C.; Kellermann, K. I.; Reid, M.; Zhao, J. H.; Goss, W. M.; Moran, J. M.

1993-01-01

Images of Sgr* A with milliarcsecond resolution obtained by using five telescopes of the partially completed Very Long Baseline Array (VLBA) in conjunction with a few additional telescopes are presented. The image of Sgr A* at a wavelength of 3.6 cm confirms almost exactly the elliptical Gaussian model that has been proposed on the basis of previous data. The source size at 1.34 cm wavelength is 2.4 +/- 0.2 mas, similar to previous results. At both wavelengths, the radio source is smooth, without detectable fine structure. These observations support the suggestion that the radio emission from Sgr A* is strongly scattered by electron-density fluctuations along the line of sight. On the assumption that the emission is due to a black hole accreting stellar winds from massive stars in the central 0.5 pc, the observations are consistent with a black hole mass of less than about 2 million solar masses.

KSC-00pp1212

NASA Image and Video Library

2000-08-30

Workers rise to the occasion on accordion lifts as they oversee the movement of solar array in front of them. The solar array will be installed onto the Integrated Equipment Assembly (IEA). A component of the International Space Station, the solar array is the second one being installed on the IEA. The arrays are scheduled to be launched on mission STS-97 in late November along with the P6 truss. The Station’s electrical power system (EPS) will use eight photovoltaic solar arrays to convert sunlight to electricity. Each of the eight solar arrays will be 112 feet long by 39 feet wide. The solar arrays are mounted on a “blanket” that can be folded like an accordion for delivery. Once in orbit, astronauts will deploy the blankets to their full size. Gimbals will be used to rotate the arrays so that they will face the Sun to provide maximum power to the Space Station

KSC-00pp1213

NASA Image and Video Library

2000-08-30

An overhead crane in the Space Station Processing Facility lifts a solar array as workers stand by to help guide it. The solar array will be installed onto the Integrated Equipment Assembly (IEA). A component of the International Space Station, the solar array is the second one being installed on the IEA. The arrays are scheduled to be launched on mission STS-97 in late November along with the P6 truss. The Station’s electrical power system (EPS) will use eight photovoltaic solar arrays to convert sunlight to electricity. Each of the eight solar arrays will be 112 feet long by 39 feet wide. The solar arrays are mounted on a “blanket” that can be folded like an accordion for delivery. Once in orbit, astronauts will deploy the blankets to their full size. Gimbals will be used to rotate the arrays so that they will face the Sun to provide maximum power to the Space Station

The IceCube Neutrino Observatory, the Pierre Auger Observatory and the Telescope Array: Joint Contribution to the 35th International Cosmic Ray Conference (ICRC 2017)

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

Aartsen, M. G.; et al.

Joint contributions of the IceCube Collaboration, the Telescope Array Collaboration, and the Pierre Auger Collaboration to the 35th International Cosmic Ray Conference (ICRC 2017), 12-20 July 2017, Bexco, Busan, Korea.

First Observations from the Multi-Application Solar Telescope (MAST) Narrow-Band Imager

NASA Astrophysics Data System (ADS)

Mathew, Shibu K.; Bayanna, Ankala Raja; Tiwary, Alok Ranjan; Bireddy, Ramya; Venkatakrishnan, Parameswaran

2017-08-01

The Multi-Application Solar Telescope is a 50 cm off-axis Gregorian telescope recently installed at the Udaipur Solar Observatory, India. In order to obtain near-simultaneous observations at photospheric and chromospheric heights, an imager optimized for two or more wavelengths is being integrated with the telescope. Two voltage-tuneable lithium-niobate Fabry-Perot etalons along with a set of interference blocking filters have been used for developing the imager. Both of the etalons are used in tandem for photospheric observations in Fe i 6173 Å and chromospheric observation in Hα 6563 Å spectral lines, whereas only one of the etalons is used for the chromospheric Ca II line at 8542 Å. The imager is also being used for spectropolarimetric observations. We discuss the characterization of the etalons at the above wavelengths, detail the integration of the imager with the telescope, and present a few sets of observations taken with the imager set-up.

The Green Bank Telescope: Transformational Science for the Next Decade.

NASA Astrophysics Data System (ADS)

Wootten, Al; GBO Staff

2018-01-01

The Robert C Byrd Green Bank Telescope has met its design goal of providing high-quality observations at 115 GHz. The accurate small beam of the telescope at high frequencies is leveraged by deployment of multi beam receivers. An overview is presented. Observers now have access to the new, 16-pixel, 3-mm Argus receiver, which is providing high-dynamic range images over wide fields for the multitude of spectral lines between 85 and 115 GHz. The successful performance of Argus, and its modular design, demonstrates that receivers with many more pixels could be built for the GBT. A 12 x 12 array of the Argus design would have mapping speeds about nine times faster than Argus without suffering any degradation in performance for the outer pixels in the array. The Observatory plans to build the next-generation Argus instrument (Argus+) with 144-pixels, a footprint 5'x5', and 7" resolution at 110 GHz. The project will be a collaboration between the Green Bank Observatory and university groups, who will supply key components. The key science drivers for Argus+ are studies of molecular filaments in the Milky Way, studies of molecular clouds in nearby galaxies, and the observations of rapidly evolving solar system objects. Observers also have access to MUSTANG-2, a 223-feedhorn bolometer camera which was commissioned on the GBT in spring 2016, and was offered for observations on a shared risk basis, in collaboration with the instrument team, in the 2018A GBO proposal call. Several features distinguish it from its predecessor, MUSTANG: A new, microstrip-coupled detector design yields higher sensitivity and less susceptibility to environmental microphonics. Detectors are feedhorn coupled, with the sum of two linear polarizations measured by a single TES per feed. The instantaneous field of view is 4 arcminutes (vs 42 arcseconds for MUSTANG) The receiver design incorporates a tilted refrigerator and receiver rotator, resulting in much lower dependence of cooling performance on telescope elevation. The detector readout is the first astronomical use of microwave resonators to multiplex TES bolometers. MUSTANG-2 has been developed by a collaboration including the University of Pennsylvania, NIST, NRAO, the University of Michigan, and Cardiff University. A 7-pixel K-band Feed Array covering 18-28 GHz with Dual polarization feeds and a noise temperature < 40-50 K has been available for several years. The array offers an instantaneous bandwidth/beam of 1.8 GHz. Future upgrade concepts under study envision increasing the number of beams by an order of magnitude.

Characterization of optical turbulence at the GREGOR solar telescope: temporal and local behavior and its influence on the solar observations

NASA Astrophysics Data System (ADS)

Sprung, D.; Sucher, E.; Stein, K.; von der Lühe, O.; Berkefeld, Th.

2016-10-01

Local atmospheric turbulence at the telescope level is regarded as a major reason for affecting the performance of the adaptive optics systems using wavelengths in the visible and infrared for solar observations. During the day the air masses around the telescope dome are influenced by flow distortions. Additionally heating of the infrastructure close to telescope causes thermal turbulence. Thereby optical turbulence is produced and leads to quality changes in the local seeing throughout the day. Image degradation will be yielded affecting the performance of adaptive optical systems. The spatial resolution of the solar observations will be reduced. For this study measurements of the optical turbulence, represented by the structure function parameter of the refractive index Cn2 were performed on several locations at the GREGOR telescope at the Teide observatory at Tenerife at the Canary Islands / Spain. Since September 2012 measurements of Cn2 were carried out between the towers of the Vacuum Tower Telescope (VTT) and of GREGOR with a laser-scintillometer. The horizontal distance of the measurement path was about 75 m. Additional from May 2015 up to March 2016 the optical turbulence was determined at three additional locations close to the solar telescope GREGOR. The optical turbulence is derived from sonic anemometer measurements. Time series of the sonic temperature are analyzed and compared to the direct measurements of the laser scintillometer. Meteorological conditions are investigated, especially the influence of the wind direction. Turbulence of upper atmospheric layers is not regarded. The measured local turbulence is compared to the system performance of the GREGOR telescopes. It appears that the mountain ridge effects on turbulence are more relevant than any local causes of seeing close to the telescope. Results of these analyses and comparison of nearly one year of measurements are presented and discussed.

Simultaneous operation and control of about 100 telescopes for the Cherenkov Telescope Array

NASA Astrophysics Data System (ADS)

Wegner, P.; Colomé, J.; Hoffmann, D.; Houles, J.; Köppel, H.; Lamanna, G.; Le Flour, T.; Lopatin, A.; Lyard, E.; Melkumyan, D.; Oya, I.; Panazol, L.-I.; Punch, M.; Schlenstedt, S.; Schmidt, T.; Stegmann, C.; Schwanke, U.; Walter, R.; Consortium, CTA

2012-12-01

The Cherenkov Telescope Array (CTA) project is an initiative to build the next generation ground-based very high energy (VHE) gamma-ray instrument. Compared to current imaging atmospheric Cherenkov telescope experiments CTA will extend the energy range and improve the angular resolution while increasing the sensitivity up to a factor of 10. With about 100 separate telescopes it will be operated as an observatory open to a wide astrophysics and particle physics community, providing a deep insight into the non-thermal high-energy universe. The CTA Array Control system (ACTL) is responsible for several essential control tasks supporting the evaluation and selection of proposals, as well as the preparation, scheduling, and finally the execution of observations with the array. A possible basic distributed software framework for ACTL being considered is the ALMA Common Software (ACS). The ACS framework follows a container component model and contains a high level abstraction layer to integrate different types of device. To achieve a low-level consolidation of connecting control hardware, OPC UA (OPen Connectivity-Unified Architecture) client functionality is integrated directly into ACS, thus allowing interaction with other OPC UA capable hardware. The CTA Data Acquisition System comprises the data readout of all cameras and the transfer of the data to a camera server farm, thereby using standard hardware and software technologies. CTA array control is also covering conceptions for a possible array trigger system and the corresponding clock distribution. The design of the CTA observations scheduler is introducing new algorithmic technologies to achieve the required flexibility.

Skylab

NASA Image and Video Library

1970-01-01

This is a photograph of a technician checking on a solar array wing for the Orbital Workshop as it is deployed. A solar array, consisting of two wings covered on one side with solar cells, was mounted outside the workshop to generate electrical power to augment the power generated by another solar array mounted on the solar observatory.

The Cherenkov Telescope Array production system for Monte Carlo simulations and analysis

NASA Astrophysics Data System (ADS)

Arrabito, L.; Bernloehr, K.; Bregeon, J.; Cumani, P.; Hassan, T.; Haupt, A.; Maier, G.; Moralejo, A.; Neyroud, N.; pre="for the"> CTA Consortium, DIRAC Consortium,

2017-10-01

The Cherenkov Telescope Array (CTA), an array of many tens of Imaging Atmospheric Cherenkov Telescopes deployed on an unprecedented scale, is the next-generation instrument in the field of very high energy gamma-ray astronomy. An average data stream of about 0.9 GB/s for about 1300 hours of observation per year is expected, therefore resulting in 4 PB of raw data per year and a total of 27 PB/year, including archive and data processing. The start of CTA operation is foreseen in 2018 and it will last about 30 years. The installation of the first telescopes in the two selected locations (Paranal, Chile and La Palma, Spain) will start in 2017. In order to select the best site candidate to host CTA telescopes (in the Northern and in the Southern hemispheres), massive Monte Carlo simulations have been performed since 2012. Once the two sites have been selected, we have started new Monte Carlo simulations to determine the optimal array layout with respect to the obtained sensitivity. Taking into account that CTA may be finally composed of 7 different telescope types coming in 3 different sizes, many different combinations of telescope position and multiplicity as a function of the telescope type have been proposed. This last Monte Carlo campaign represented a huge computational effort, since several hundreds of telescope positions have been simulated, while for future instrument response function simulations, only the operating telescopes will be considered. In particular, during the last 18 months, about 2 PB of Monte Carlo data have been produced and processed with different analysis chains, with a corresponding overall CPU consumption of about 125 M HS06 hours. In these proceedings, we describe the employed computing model, based on the use of grid resources, as well as the production system setup, which relies on the DIRAC interware. Finally, we present the envisaged evolutions of the CTA production system for the off-line data processing during CTA operations and the instrument response function simulations.

TESS Spacecraft Solar Panel Array Deployment Testing

NASA Image and Video Library

2018-02-21

Technicians dressed in clean room suits monitor the progress as both solar panels are deployed on NASA's Transiting Exoplanet Survey Satellite (TESS) inside the Payload Hazardous Servicing Facility (PHSF) at the agency's Kennedy Space Center in Florida. Inside the PHSF, the satellite is being processed and prepared for its flight. TESS is scheduled to launch atop a SpaceX Falcon 9 rocket from Space Launch Complex 40 at Cape Canaveral Air Force Station. The satellite is the next step in NASA's search for planets outside our solar system, known as exoplanets. TESS is a NASA Astrophysics Explorer mission led and operated by MIT in Cambridge, Massachusetts, and managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Dr. George Ricker of MIT’s Kavli Institute for Astrophysics and Space Research serves as principal investigator for the mission. Additional partners include Orbital ATK, NASA’s Ames Research Center, the Harvard-Smithsonian Center for Astrophysics and the Space Telescope Science Institute. More than a dozen universities, research institutes and observatories worldwide are participants in the mission. NASA’s Launch Services Program is responsible for launch management.

TESS Spacecraft Solar Panel Array Deployment Testing

NASA Image and Video Library

2018-02-21

Technicians dressed in clean room suits check the solar panels, which have been deployed, on NASA's Transiting Exoplanet Survey Satellite (TESS) inside the Payload Hazardous Servicing Facility (PHSF) at the agency's Kennedy Space Center in Florida. Inside the PHSF, the satellite is being processed and prepared for its flight. TESS is scheduled to launch atop a SpaceX Falcon 9 rocket from Space Launch Complex 40 at Cape Canaveral Air Force Station. The satellite is the next step in NASA's search for planets outside our solar system, known as exoplanets. TESS is a NASA Astrophysics Explorer mission led and operated by MIT in Cambridge, Massachusetts, and managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland. Dr. George Ricker of MIT’s Kavli Institute for Astrophysics and Space Research serves as principal investigator for the mission. Additional partners include Orbital ATK, NASA’s Ames Research Center, the Harvard-Smithsonian Center for Astrophysics and the Space Telescope Science Institute. More than a dozen universities, research institutes and observatories worldwide are participants in the mission. NASA’s Launch Services Program is responsible for launch management.

Space Shuttle Projects

NASA Image and Video Library

2002-03-05

Astronaut James H. Newman, mission specialist, floats about in the Space Shuttle Columbia's cargo bay while working in tandem with astronaut Michael J. Massimino (out of frame),mission specialist, during the STS-109 mission's second day of extravehicular activity (EVA). Inside Columbia's cabin, astronaut Nancy J. Currie, mission specialist, controlled the Remote Manipulator System (RMS) to assist the two in their work on the Hubble Space Telescope (HST). The RMS was used to capture the telescope and secure it into Columbia's cargo bay.Part of the giant telescope's base, latched down in the payload bay, can be seen behind Newman. The Space Shuttle Columbia STS-109 mission lifted off March 1, 2002 with goals of repairing and upgrading the HST. The Marshall Space Flight Center in Huntsville, Alabama had responsibility for the design, development, and contruction of the HST, which is the most powerful and sophisticated telescope ever built. STS-109 upgrades to the HST included: replacement of the solar array panels; replacement of the power control unit (PCU); replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS); and installation of the experimental cooling system for the Hubble's Near-Infrared Camera and Multi-object Spectrometer (NICMOS), which had been dormant since January 1999 when its original coolant ran out. Lasting 10 days, 22 hours, and 11 minutes, the STS-109 mission was the 108th flight overall in NASA's Space Shuttle Program.

Space Shuttle Projects

NASA Image and Video Library

2002-03-07

STS-109 Astronaut Michael J. Massimino, mission specialist, perched on the Shuttle's robotic arm, is preparing to install the Electronic Support Module (ESM) in the aft shroud of the Hubble Space telescope (HST), with the assistance of astronaut James H. Newman (out of frame). The module will support a new experimental cooling system to be installed during the next day's fifth and final space walk of the mission. That cooling system is designed to bring the telescope's Near-Infrared Camera and Multi Spectrometer (NICMOS) back to life the which had been dormant since January 1999 when its original coolant ran out. The Space Shuttle Columbia STS-109 mission lifted off March 1, 2002 with goals of repairing and upgrading the Hubble Space Telescope (HST). The Marshall Space Flight Center in Huntsville, Alabama had the responsibility for the design, development, and construction of the HST, which is the most powerful and sophisticated telescope ever built. In addition to the installation of the experimental cooling system for the Hubble's Near-Infrared Camera and NICMOS, STS-109 upgrades to the HST included replacement of the solar array panels, replacement of the power control unit (PCU), and replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS). Lasting 10 days, 22 hours, and 11 minutes, the STS-109 mission was the 108th flight overall in NASA's Space Shuttle Program.

FINDING EXTRATERRESTRIAL LIFE USING GROUND-BASED HIGH-DISPERSION SPECTROSCOPY

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

Snellen, I. A. G.; Le Poole, R.; Brogi, M.

2013-02-20

Exoplanet observations promise one day to unveil the presence of extraterrestrial life. Atmospheric compounds in strong chemical disequilibrium would point to large-scale biological activity just as oxygen and methane do in the Earth's atmosphere. The cancellation of both the Terrestrial Planet Finder and Darwin missions means that it is unlikely that a dedicated space telescope to search for biomarker gases in exoplanet atmospheres will be launched within the next 25 years. Here we show that ground-based telescopes provide a strong alternative for finding biomarkers in exoplanet atmospheres through transit observations. Recent results on hot Jupiters show the enormous potential ofmore » high-dispersion spectroscopy to separate the extraterrestrial and telluric signals, making use of the Doppler shift of the planet. The transmission signal of oxygen from an Earth-twin orbiting a small red dwarf star is only a factor of three smaller than that of carbon monoxide recently detected in the hot Jupiter {tau} Booetis b, albeit such a star will be orders of magnitude fainter. We show that if Earth-like planets are common, the planned extremely large telescopes can detect oxygen within a few dozen transits. Ultimately, large arrays of dedicated flux-collector telescopes equipped with high-dispersion spectrographs can provide the large collecting area needed to perform a statistical study of life-bearing planets in the solar neighborhood.« less

Instrument Design of the Large Aperture Solar UV Visible and IR Observing Telescope (SUVIT) for the SOLAR-C Mission

NASA Astrophysics Data System (ADS)

Suematsu, Y.; Katsukawa, Y.; Shimizu, T.; Ichimoto, K.; Takeyama, N.

2012-12-01

We present an instrumental design of one major solar observation payload planned for the SOLAR-C mission: the Solar Ultra-violet Visible and near IR observing Telescope (SUVIT). The SUVIT is designed to provide high-angular-resolution investigation of the lower solar atmosphere, from the photosphere to the uppermost chromosphere, with enhanced spectroscopic and spectro-polarimetric capability in wide wavelength regions from 280 nm (Mg II h&k lines) to 1100 nm (He I 1083 nm line) with 1.5 m class aperture and filtergraphic and spectrographic instruments.

2016 SPD: Day 1

NASA Astrophysics Data System (ADS)

Kohler, Susanna

2016-06-01

Editors note: This week were in Boulder, Colorado at the 47th meeting of the AAS Solar Physics Division (SPD). Follow along to catch some of the latest news from the field of solar physics!The 2016 SPD meeting was launched this morning from the University of Colorado Boulder campus. Two of the hot topics at this years meeting include celebration of the recent move of the National Solar Observatorys headquarters to Boulder, and discussion of the future Daniel K. Inouye Solar Telescope (DKIST, formerly the Advanced Technology Solar Telescope, ATST). DKIST, planned for a 2019 completion in Hawaii, is the next big telescope on the horizon for solar physics.Todays press conference had an interesting focus: instruments providing new high-energy observations of the Sun. Representatives from four different instruments were here to talk about some of the latest X-ray solar observations.GRIPSThe GRIPS payload flew at 130,000 ft over Antarctica on a giant balloon in January 2016. [NASA/Albert Shih]First up, Albert Shih (NASA Goddard) described the Gamma-Ray Imager/Polarimeter for Solar flares, or GRIPS. GRIPS is a balloon-borne instrument designed to detect X-rays and gamma rays emitted during solar flares. Up to tens of a percent of the energy in solar flares is emitted in the form of accelerated particles, but the physics behind this process is not well understood. GRIPS observes where the highest-energy particles are accelerated, in an effort to learn more about the process.GRIPS was launched on 19 January, 2016 and flew for roughly 12 days gathering ~1 million seconds of data! The logistics of this instruments flight are especially interesting, since it was launched from Antarctica and carried by a balloon at a whopping elevation of 130,000 ft (to get high enough that the atmosphere doesnt absorb all the photons GRIPS is trying to observe). Though the data from the mission has been retrieved, the bulk of the hardware remains where it landed at the end of January. It must wait for the warmer Antarctic weather in December before a team will be able to reach the instrument and recover it!Over the 12 days it flew, GRIPS observed 21 small, C-class solar flares. Data analysis is currently underway, and the team hopes that these observations will help improve our understanding of the processes underlying these solar flares.The FOXSI mission launches on a sounding rocket, taking roughly five minutes of hard X-ray data of the Sun during its flights. [NASA/FOXSI]FOXSINext, Camilo Buitrago-Casas (UC Berkeley) introduced us to the Focusing Optics X-ray Solar Imager (FOXSI) sounding rocket. More than anything, FOXSI is a test of new instrumentation that may be key to future observations of the Sun in hard X-rays.FOXSI is a focusing telescope something that is significantly more difficult to do with hard X-rays than it is with optical telescopes. Hard X-rays are difficult to bounce off of mirrors since, due to their high energy, they simply pass through the mirrors! The trick is to capture the X-rays at a grazing angle, sending them through a series of nested mirrors that progressively focus the light. Due to this process and new-technology detectors, FOXSI is able to produce very high-quality, low-noise images of some of the hottest solar sources in fine detail.FOXSI has now flown twice, with a third flight planned for 2018. Each flight gains about five minutes of data while the sounding rocket is above the Earths atmosphere in its parabolic trajectory. While this instrument has already produced a wealth of data about tiny solar flares, the ultimate goal is to get FOXSIs technology on a space-based observatory, allowing for dedicated and longer observations of solar flares.NuSTARNext, Lindsay Glesener (University of Minnesota) spoke about the Nuclear Spectroscopic Telescope Array (NuSTAR) space telescope, which actually has this opportunity for long solar observations except that its a little busy. NuSTAR was primarily designed to look at faint sources in the distant universe. But a few times a year, it takes a few hours to look closer to home, turning to point at the Sun.Artists concept of NuSTAR, a high-energy space telescope that occasionally takes a break from observing the distant universe to instead point at the Sun. [NASA]Due to NuSTARs extreme sensitivity, there are obviously some challenges in pointing it directly at a nearby, high-intensity source! Large solar flares would completely swamp the telescopes detectors, but in quiet conditions, NuSTAR is an excellent tool for detecting faint sources.As a result, NuSTAR recently detected the smallest, faintest X-ray flare ever imaged at high energies. Tiny flares such as this one are very different from the enormous eruptions were used to seeing in solar images; these small flares would go unnoticed by a less sensitive instrument. Theyre interesting to study, however, because they might provide the solution to the coronal heating problem the question of how the enormous temperature of the solar corona is sustained. Its thought that continuous eruption of small solar flares could potentially provide the heating necessary to explain the coronas temperature.MinXSSThe last speaker of the press conference was Amir Caspi (Southwest Research Institute), who told us about the Miniature X-ray Solar Spectrometer, or MinXSS. MinXSS is a NASA-funded CubeSat a small but full-feature satellite roughly the size of a loaf of bread. It was deployed from the International Space Station just two weeks ago (16 May), and saw its first light last night (30 May)!MinXSS will detect soft X-rays from the Sun, with the goal of gaining a better understanding solar flares, nanoflares, and how these impact the Earth. When solar X-rays are absorbed by the Earths upper atmosphere, the atmosphere heats up with photons of different energies causing heating in different atmospheric layers. Understanding this interaction isimportant for makingpredictions about how communications signals traveling through the Earths ionosphere might be affected.MinXSSs mission is roughly 6-12 months long, with a second mission planned after the conclusion of the current one. The team is looking forward to MinXSSs entry into science mode in a few days time, and the data that will hopefully follow! You can keep up with the latest news from MinXSS on facebook and twitter.BonusCheck out the gif below that shows the deployment of MinXSS (the one in front) and a second CubeSat, CADRE, from the ISS! This compilation of photos was put together by James Mason, MinXSS project manager. The photos were taken from the ISS by astronaut Tim Peake. [NASA

The revised solar array synthesis computer program

NASA Technical Reports Server (NTRS)

1970-01-01

The Revised Solar Array Synthesis Computer Program is described. It is a general-purpose program which computes solar array output characteristics while accounting for the effects of temperature, incidence angle, charged-particle irradiation, and other degradation effects on various solar array configurations in either circular or elliptical orbits. Array configurations may consist of up to 75 solar cell panels arranged in any series-parallel combination not exceeding three series-connected panels in a parallel string and no more than 25 parallel strings in an array. Up to 100 separate solar array current-voltage characteristics, corresponding to 100 equal-time increments during the sunlight illuminated portion of an orbit or any 100 user-specified combinations of incidence angle and temperature, can be computed and printed out during one complete computer execution. Individual panel incidence angles may be computed and printed out at the user's option.

Feasibility of utilizing Cherenkov Telescope Array gamma-ray telescopes as free-space optical communication ground stations.

PubMed

Carrasco-Casado, Alberto; Vilera, Mariafernanda; Vergaz, Ricardo; Cabrero, Juan Francisco

2013-04-10

The signals that will be received on Earth from deep-space probes in future implementations of free-space optical communication will be extremely weak, and new ground stations will have to be developed in order to support these links. This paper addresses the feasibility of using the technology developed in the gamma-ray telescopes that will make up the Cherenkov Telescope Array (CTA) observatory in the implementation of a new kind of ground station. Among the main advantages that these telescopes provide are the much larger apertures needed to overcome the power limitation that ground-based gamma-ray astronomy and optical communication both have. Also, the large number of big telescopes that will be built for CTA will make it possible to reduce costs by economy-scale production, enabling optical communications in the large telescopes that will be needed for future deep-space links.

Hubble Space Telescope: Servicing Mission 3A. Media Reference Guide

NASA Technical Reports Server (NTRS)

1999-01-01

Since its launch in April 1990, the Hubble Space Telescope (HST) has provided scientific data and images of unprecedented resolution from which many new and exciting discoveries have been made. The Telescope's purpose is to spend 20 years probing the farthest and faintest reaches of the cosmos. Crucial to fulfilling this objective is a series of on-orbit manned servicing missions. The First Servicing Mission (SM1) took place in December 1993 and the Second Servicing Mission (SM2) was flown in February 1997. During these missions, astronauts perform planned repairs and maintenance activities to restore and upgrade the observatory s capabilities. To facilitate this process, the Telescope s designers configured science instruments and several vital engineering subsystems as Orbital Replacement Units (ORU) -- modular packages with standardized fittings accessible to astronauts in pressurized suits. Hubble's Third Servicing Mission has been separated into two parts: Servicing Mission 3A (SM3A) will fly in Fall of 1999 and Servicing Mission 3B (SM3B) is planned for 2001. The principal objective of SM3A is to replace all six gyroscopes that compose the three Rate Sensor Units (RSU). In addition, space-walking astronauts will install a new Advanced Computer that will dramatically increase the computing power, speed, and storage capability of HST. They will change out one of the Fine Guidance Sensors (FGS) and replace a tape recorder with a new Solid State Recorder (SSR). The Extravehicular Activity (EVA) crew also will install a new S-band Single-Access Transmitter (SSAT), and Voltage/Temperature Improvement Kits (VIK) for the Telescope s nickel-hydrogen batteries. Finally, they will begin repair of the multilayer insulation on Hubble s outer surface. During SM3B astronauts will install a new science instrument, the Advanced Camera for Surveys (ACS), and an Aft Shroud Cooling System (ASCS) for the other axial science instruments. They will attach a new cryogenic cooler to the Near-Infrared Camera and Multi-Object Spectrometer (NICMOS). They also will replace the HST flexible Solar Arrays with new high-performance rigid arrays.

Alignment displacements of the solar optical telescope primary mirror

NASA Technical Reports Server (NTRS)

Medenica, W. V.

1978-01-01

Solar optical telescope is a space shuttle payload which is at the present time (1978) being planned. The selected alignment method for the telescope's primary mirror is such that the six inclined legs supporting the mirror are at the same time motorized alignment actuators, changing their own length according to the alignment requirement and command. The alignment displacements were described, including circumvention of some apparent NASTRAN limitations.

Feasibility study of the solar scientific instruments for Spacelab/Orbiter

NASA Technical Reports Server (NTRS)

Leritz, J.; Rasser, T.; Stone, E.; Lockhart, B.; Nobles, W.; Parham, J.; Eimers, D.; Peterson, D.; Barnhart, W.; Schrock, S.

1981-01-01

The feasibility and economics of mounting and operating a set of solar scientific instruments in the backup Skylab Apollo Telescope Mount (ATM) hardware was evaluated. The instruments used as the study test payload and integrated into the ATM were: the Solar EUV Telescope/Spectrometer; the Solar Active Region Observing Telescope; and the Lyman Alpha White Light Coronagraph. The backup ATM hardware consists of a central cruciform structure, called the "SPAR', a "Sun End Canister' and a "Multiple Docking Adapter End Canister'. Basically, the ATM hardware and software provides a structural interface for the instruments; a closely controlled thermal environment; and a very accurate attitude and pointing control capability. The hardware is an identical set to the hardware that flow on Skylab.

Signals of HE atmospheric μ decay in flight around the Sun’s albedo versus astrophysical νμ and ντ traces in the Moon shadow

NASA Astrophysics Data System (ADS)

Fargion, Daniele; Oliva, Pietro; de Sanctis Lucentini, Pier Giorgio; Khlopov, Maxim Yu.

The Sun albedo of Cosmic Rays (CRs) at GeVs energy has been discovered recently by the FERMI satellite. They are traces of atmospheric CRs hitting solar atmosphere and reflecting skimming gamma photons. Even if relevant for astrophysics, as being a trace of atmospheric solar CR noises they cannot offer any signal of neutrino astronomy. On the contrary, the Moon with no atmosphere, may become soon a novel filtering calorimeter and an amplifier of energetic muon astronomical neutrinos (at TeV up to hundred TeVs energy); these lepton tracks leave an imprint in their beta decay while in flight to Earth. Their TeV electron air-shower are among the main signals. Also, a more energetic, but more rare, PeV up to EeV tau lunar neutrino events may be escaping as a tau lepton from the Moon: τ PeV secondaries, then, may be shining on Earth’s atmosphere in lunar shadows in a surprising way. One or a few gamma air-shower events inside the Moon shadows may occur each year in near future Cherenkov telescope array (CTA) or large high altitude air shower observatory (LHAASO) TeV gamma array detector, assuming a nonnegligible astrophysical TeV up to hundred TeV neutrino component (with respect to our terrestrial ruling atmospheric ones); these signals will open a new wonderful passe-partout keyhole for neutrino, been seen along the Moon. The lunar solid angle is small and the muon or tau expected rate is rare, but with the future largest tau radio array as the giant radio array for neutrino detection (GRAND), one might well discover such neutrino imprint.

Prospects for PWNe and SNRs science with the ASTRI mini-array of pre-production small-sized telescopes of the Cherenkov telescope array

NASA Astrophysics Data System (ADS)

Burtovoi, A.; Zampieri, L.; Giuliani, A.; Bigongiari, C.; Di Pierro, F.; Stamerra, A.

2017-01-01

The development and construction of the Cherenkov Telescope Array (CTA) opens up new opportunities for the study of very high energy (VHE, E > 100 GeV) sources. As a part of CTA, the ASTRI project, led by INAF, has one of the main goals to develop one of the mini-arrays of CTA pre-production telescopes, proposed to be installed at the CTA southern site. Thanks to the innovative dual-mirror optical design of its small-sized telescopes, the ASTRI mini-array will be characterized by a large field of view, an excellent angular resolution and a good sensitivity up to energies of several tens of TeV. Pulsar wind nebulae, along with Supernova Remnants, are among the most abundant sources that will be identified and investigated, with the ultimate goal to move significantly closer to an understanding of the origin of cosmic rays (CR). As part of the ongoing effort to investigate the scientific capabilities for both CTA as a whole and the ASTRI mini-array, we performed simulations of the Vela X region. We simulated its extended VHE γ-ray emission using the results of the detailed H.E.S.S. analysis of this source. We estimated the resolving capabilities of the diffuse emission and the detection significance of the pulsar with both CTA as a whole and the ASTRI mini-array. Moreover with these instruments it will be possible to observe the high-energy end of SNRs spectrum, searching for particles with energies near the cosmic-rays "knee" (E ˜ 1015 eV). We simulated a set of ASTRI mini-array observations for one young and an evolved SNRs in order to test the capabilities of this instrument to discover and study PeVatrons on the Galactic plane.

Superconductor lunar telescopes --Abstract only

NASA Technical Reports Server (NTRS)

Chen, P. C.; Pitts, R.; Shore, S.; Oliversen, R.; Stolarik, J.; Segal, K.; Hojaji, H.

1994-01-01

We propose a new type of telescope designed specifically for the lunar environment of high vacuum and low temperature. Large area UV-Visible-IR telescope arrays can be built with ultra-light-weight replica optics. High T(sub c) superconductors provide support, steering, and positioning. Advantages of this approach are light-weight payload compatible with existing launch vehicles, configurable large area optical arrays, no excavation or heavy construction, and frictionless electronically controlled mechanisms. We have built a prototype and will be demonstarting some of its working characteristics.

Rearranging the lenslet array of the compact passive interference imaging system with high resolution

NASA Astrophysics Data System (ADS)

Liu, Gang; Wen, Desheng; Song, Zongxi

2017-10-01

With the development of aeronautics and astronautics, higher resolution requirement of the telescope was necessary. However, the increase in resolution of conventional telescope required larger apertures, whose size, weight and power consumption could be prohibitively expensive. This limited the further development of the telescope. This paper introduced a new imaging technology using interference—Compact Passive Interference Imaging Technology with High Resolution, and proposed a rearranging method for the arrangement of the lenslet array to obtain continuously object spatial frequency.

Superconductor lunar telescopes --Abstract only

NASA Astrophysics Data System (ADS)

Chen, P. C.; Pitts, R.; Shore, S.; Oliversen, R.; Stolarik, J.; Segal, K.; Hojaji, H.

1994-06-01

We propose a new type of telescope designed specifically for the lunar environment of high vacuum and low temperature. Large area UV-Visible-IR telescope arrays can be built with ultra-light-weight replica optics. High Tc superconductors provide support, steering, and positioning. Advantages of this approach are light-weight payload compatible with existing launch vehicles, configurable large area optical arrays, no excavation or heavy construction, and frictionless electronically controlled mechanisms. We have built a prototype and will be demonstarting some of its working characteristics.

Adaptive optics for array telescopes using piston-and-tilt wave-front sensing

NASA Technical Reports Server (NTRS)

Wizinowich, P.; Mcleod, B.; Lloyd-Yhart, M.; Angel, J. R. P.; Colucci, D.; Dekany, R.; Mccarthy, D.; Wittman, D.; Scott-Fleming, I.

1992-01-01

A near-infrared adaptive optics system operating at about 50 Hz has been used to control phase errors adaptively between two mirrors of the Multiple Mirror Telescope by stabilizing the position of the interference fringe in the combined unresolved far-field image. The resultant integrated images have angular resolutions of better than 0.1 arcsec and fringe contrasts of more than 0.6. Measurements of wave-front tilt have confirmed the wavelength independence of image motion. These results show that interferometric sensing of phase errors, when combined with a system for sensing the wave-front tilt of the individual telescopes, will provide a means of achieving a stable diffraction-limited focus with segmented telescopes or arrays of telescopes.

Diffraction-limited imaging with very large telescopes; Proceedings of the NATO Advanced Study Institute, Cargese, France, Sept. 13-23, 1988

NASA Astrophysics Data System (ADS)

Alloin, D. M.; Mariotti, J.-M.

Recent advances in optics and observation techniques for very large astronomical telescopes are discussed in reviews and reports. Topics addressed include Fourier optics and coherence, optical propagation and image formation through a turbulent atmosphere, radio telescopes, continuously deformable telescopes for optical interferometry (I), amplitude estimation from speckle I, noise calibration of speckle imagery, and amplitude estimation from diluted-array I. Consideration is given to first-order imaging methods, speckle imaging with the PAPA detector and the Knox-Thompson algorithm, phase-closure imaging, real-time wavefront sensing and adaptive optics, differential I, astrophysical programs for high-angular-resolution optical I, cophasing telescope arrays, aperture synthesis for space observatories, and lunar occultations for marcsec resolution.

MILSTAR's flexible substrate solar array: Lessons learned, addendum

NASA Technical Reports Server (NTRS)

Gibb, John

1990-01-01

MILSTAR's Flexible Substrate Solar Array (FSSA) is an evolutionary development of the lightweight, flexible substrate design pioneered at Lockheed during the seventies. Many of the features of the design are related to the Solar Array Flight Experiment (SAFE), flown on STS-41D in 1984. FSSA development has created a substantial technology base for future flexible substrate solar arrays such as the array for the Space Station Freedom. Lessons learned during the development of the FSSA can and should be applied to the Freedom array and other future flexible substrate designs.

NectarCAM, a camera for the medium sized telescopes of the Cherenkov telescope array

NASA Astrophysics Data System (ADS)

Glicenstein, J.-F.; Shayduk, M.

2017-01-01

NectarCAM is a camera proposed for the medium-sized telescopes of the Cherenkov Telescope Array (CTA) which covers the core energy range of 100 GeV to 30 TeV. It has a modular design and is based on the NECTAr chip, at the heart of which is a GHz sampling Switched Capacitor Array and 12-bit Analog to Digital converter. The camera will be equipped with 265 7-photomultiplier modules, covering a field of view of 8 degrees. Each module includes photomultiplier bases, high voltage supply, pre-amplifier, trigger, readout and Ethernet transceiver. The recorded events last between a few nanoseconds and tens of nanoseconds. The expected performance of the camera are discussed. Prototypes of NectarCAM components have been built to validate the design. Preliminary results of a 19-module mini-camera are presented, as well as future plans for building and testing a full size camera.

An IBM PC-based math model for space station solar array simulation

NASA Technical Reports Server (NTRS)

Emanuel, E. M.

1986-01-01

This report discusses and documents the design, development, and verification of a microcomputer-based solar cell math model for simulating the Space Station's solar array Initial Operational Capability (IOC) reference configuration. The array model is developed utilizing a linear solar cell dc math model requiring only five input parameters: short circuit current, open circuit voltage, maximum power voltage, maximum power current, and orbit inclination. The accuracy of this model is investigated using actual solar array on orbit electrical data derived from the Solar Array Flight Experiment/Dynamic Augmentation Experiment (SAFE/DAE), conducted during the STS-41D mission. This simulator provides real-time simulated performance data during the steady state portion of the Space Station orbit (i.e., array fully exposed to sunlight). Eclipse to sunlight transients and shadowing effects are not included in the analysis, but are discussed briefly. Integrating the Solar Array Simulator (SAS) into the Power Management and Distribution (PMAD) subsystem is also discussed.

Photovoltaic solar array technology required for three wide scale generating systems for terrestrial applications: rooftop, solar farm, and satellite

NASA Technical Reports Server (NTRS)

Berman, P. A.

1972-01-01

Three major options for wide-scale generation of photovoltaic energy for terrestrial use are considered: (1) rooftop array, (2) solar farm, and (3) satellite station. The rooftop array would use solar cell arrays on the roofs of residential or commercial buildings; the solar farm would consist of large ground-based arrays, probably in arid areas with high insolation; and the satellite station would consist of an orbiting solar array, many square kilometers in area. The technology advancement requirements necessary for each option are discussed, including cost reduction of solar cells and arrays, weight reduction, resistance to environmental factors, reliability, and fabrication capability, including the availability of raw materials. The majority of the technology advancement requirements are applicable to all three options, making possible a flexible basic approach regardless of the options that may eventually be chosen. No conclusions are drawn as to which option is most advantageous, since the feasibility of each option depends on the success achieved in the technology advancement requirements specified.

Solar maximum: Solar array degradation

NASA Technical Reports Server (NTRS)

Miller, T.

1985-01-01

The 5-year in-orbit power degradation of the silicon solar array aboard the Solar Maximum Satellite was evaluated. This was the first spacecraft to use Teflon R FEP as a coverglass adhesive, thus avoiding the necessity of an ultraviolet filter. The peak power tracking mode of the power regulator unit was employed to ensure consistent maximum power comparisons. Telemetry was normalized to account for the effects of illumination intensity, charged particle irradiation dosage, and solar array temperature. Reference conditions of 1.0 solar constant at air mass zero and 301 K (28 C) were used as a basis for normalization. Beginning-of-life array power was 2230 watts. Currently, the array output is 1830 watts. This corresponds to a 16 percent loss in array performance over 5 years. Comparison of Solar Maximum Telemetry and predicted power levels indicate that array output is 2 percent less than predictions based on an annual 1.0 MeV equivalent election fluence of 2.34 x ten to the 13th power square centimeters space environment.

Space solar array reliability: A study and recommendations

NASA Astrophysics Data System (ADS)

Brandhorst, Henry W., Jr.; Rodiek, Julie A.

2008-12-01

Providing reliable power over the anticipated mission life is critical to all satellites; therefore solar arrays are one of the most vital links to satellite mission success. Furthermore, solar arrays are exposed to the harshest environment of virtually any satellite component. In the past 10 years 117 satellite solar array anomalies have been recorded with 12 resulting in total satellite failure. Through an in-depth analysis of satellite anomalies listed in the Airclaim's Ascend SpaceTrak database, it is clear that solar array reliability is a serious, industry-wide issue. Solar array reliability directly affects the cost of future satellites through increased insurance premiums and a lack of confidence by investors. Recommendations for improving reliability through careful ground testing, standardization of testing procedures such as the emerging AIAA standards, and data sharing across the industry will be discussed. The benefits of creating a certified module and array testing facility that would certify in-space reliability will also be briefly examined. Solar array reliability is an issue that must be addressed to both reduce costs and ensure continued viability of the commercial and government assets on orbit.

Multinode data acquisition and control system for the 4-element TACTIC telescope array

NASA Astrophysics Data System (ADS)

Yadav, K. K.; Chouhan, N.; Kaul, S. R.; Koul, R.

2002-03-01

An interrupt driven multinode data acquisition and control system has been developed for the 4-element gamma-ray telescope array, TACTIC. Computer networking technology and the CAMAC bus have been integrated to develop this icon-based, userfriendly failsafe system. The paper describes the salient features of the system.

National Large Solar Telescope of Russia

NASA Astrophysics Data System (ADS)

Demidov, Mikhail

One of the most important task of the modern solar physics is multi-wavelength observations of the small-scale structure of solar atmosphere on different heights, including chromosphere and corona. To do this the large-aperture telescopes are necessary. At present time there several challenging projects of the large (and even giant) solar telescopes in the world are in the process of construction or designing , the most known ones among them are 4-meter class telescopes ATST in USA and EST in Europe. Since 2013 the development of the new Large Solar Telescope (LST) with 3 meter diameter of the main mirror is started in Russia as a part (sub-project) of National Heliogeophysical Complex (NHGC) of the Russian Academy of Sciences. It should be located at the Sayan solar observatory on the altitude more then 2000 m. To avoid numerous problems of the off-axis optical telescopes (despite of the obvious some advantages of the off-axis configuration) and to meet to available financial budget, the classical on-axis Gregorian scheme on the alt-azimuth mount has been chosen. The scientific equipment of the LST-3 will include several narrow-band tunable filter devices and spectrographs for different wavelength bands, including infrared. The units are installed either at the Nasmyth focus or/and on the rotating coude platform. To minimize the instrumental polarization the polarization analyzer is located near diagonal mirror after M2 mirror. High order adaptive optics is used to achieve the diffraction limited performances. It is expected that after some modification of the optical configuration the LST-3 will operate as an approximately 1-m mirror coronograph in the near infrared spectral lines. Possibilities for stellar observations during night time are provided as well.

Space Plasma Shown to Make Satellite Solar Arrays Fail

NASA Technical Reports Server (NTRS)

Ferguson, Dale C.

1999-01-01

In 1997, scientists and engineers of the Photovoltaic and Space Environments Branch of the NASA Lewis Research Center, Maxwell Technologies, and Space Systems/Loral discovered a new failure mechanism for solar arrays on communications satellites in orbit. Sustained electrical arcs, initiated by the space plasma and powered by the solar arrays themselves, were found to have destroyed solar array substrates on some Space Systems/Loral satellites, leading to array failure. The mechanism was tested at Lewis, and mitigation strategies were developed to prevent such disastrous occurrences on-orbit in the future. Deep Space 1 is a solar-electric-powered space mission to a comet, launched on October 24, 1998. Early in 1998, scientists at Lewis and Ballistic Missile Defense Organization (BMDO) realized that some aspects of the Deep Space 1 solar arrays were nearly identical to those that had led to the failure of solar arrays on Space Systems/Loral satellites. They decided to modify the Deep Space 1 arrays to prevent catastrophic failure in space. The arrays were suitably modified and are now performing optimally in outer space. Finally, the Earth Observing System (EOS) AM1, scheduled for launch in mid-1999, is a NASA mission managed by the Goddard Space Flight Center. Realizing the importance of Lewis testing on the Loral arrays, EOS-AM1 management asked Lewis scientists to test their solar arrays to show that they would not fail in the same way. The first phase of plasma testing showed that sustained arcing would occur on the unmodified EOS-AM1 arrays, so the arrays were removed from the spacecraft and fixed. Now, Lewis scientists have finished plasma testing of the modified array configuration to ensure that EOS-AM1 will have no sustained arcing problems on-orbit.

Observatories Combine to Crack Open the Crab Nebula

NASA Image and Video Library

2017-12-08

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

Wide-Angle, Flat-Field Telescope

NASA Technical Reports Server (NTRS)

Hallam, K. L.; Howell, B. J.; Wilson, M. E.

1987-01-01

All-reflective system unvignetted. Wide-angle telescope uses unobstructed reflecting elements to produce flat image. No refracting elements, no chromatic aberration, and telescope operates over spectral range from infrared to far ultraviolet. Telescope used with such image detectors as photographic firm, vidicons, and solid-state image arrays.

The High-Level Interface Definitions in the ASTRI/CTA Mini Array Software System (MASS)

NASA Astrophysics Data System (ADS)

Conforti, V.; Tosti, G.; Schwarz, J.; Bruno, P.; Cefal‘A, M.; Paola, A. D.; Gianotti, F.; Grillo, A.; Russo, F.; Tanci, C.; Testa, V.; Antonelli, L. A.; Canestrari, R.; Catalano, O.; Fiorini, M.; Gallozzi, S.; Giro, E.; Palombara, N. L.; Leto, G.; Maccarone, M. C.; Pareschi, G.; Stringhetti, L.; Trifoglio, M.; Vercellone, S.; Astri Collaboration; Cta Consortium

2015-09-01

ASTRI (Astrofisica con Specchi a Tecnologia Replicante Italiana) is a Flagship Project funded by the Italian Ministry of Education, University and Research, and led by INAF, the Italian National Institute of Astrophysics. Within this framework, INAF is currently developing an end-to-end prototype, named ASTRI SST-2M, of a Small Size Dual-Mirror Telescope for the Cherenkov Telescope Array, CTA. A second goal of the project is the realization of the ASTRI/CTA mini-array, which will be composed of seven SST-2M telescopes placed at the CTA Southern Site. The ASTRI Mini Array Software System (MASS) is designed to support the ASTRI/CTA mini-array operations. MASS is being built on top of the ALMA Common Software (ACS) framework, which provides support for the implementation of distributed data acquisition and control systems, and functionality for log and alarm management, message driven communication and hardware devices management. The first version of the MASS system, which will comply with the CTA requirements and guidelines, will be tested on the ASTRI SST-2M prototype. In this contribution we present the interface definitions of the MASS high level components in charge of the ASTRI SST-2M observation scheduling, telescope control and monitoring, and data taking. Particular emphasis is given to their potential reuse for the ASTRI/CTA mini-array.

Balloon flight test of a Compton telescope based on scintillators with silicon photomultiplier readouts

NASA Astrophysics Data System (ADS)

Bloser, P. F.; Legere, J. S.; Bancroft, C. M.; Ryan, J. M.; McConnell, M. L.

2016-03-01

We present the results of the first high-altitude balloon flight test of a concept for an advanced Compton telescope making use of modern scintillator materials with silicon photomultiplier (SiPM) readouts. There is a need in the fields of high-energy astronomy and solar physics for new medium-energy gamma-ray ( 0.4-10 MeV) detectors capable of making sensitive observations of both line and continuum sources over a wide dynamic range. A fast scintillator-based Compton telescope with SiPM readouts is a promising solution to this instrumentation challenge, since the fast response of the scintillators permits both the rejection of background via time-of-flight (ToF) discrimination and the ability to operate at high count rates. The Solar Compton Telescope (SolCompT) prototype presented here was designed to demonstrate stable performance of this technology under balloon-flight conditions. The SolCompT instrument was a simple two-element Compton telescope, consisting of an approximately one-inch cylindrical stilbene crystal for a scattering detector and a one-inch cubic LaBr3:Ce crystal for a calorimeter detector. Both scintillator detectors were read out by 2×2 arrays of Hamamatsu S11828-3344 MPPC devices. Custom front-end electronics provided optimum signal rise time and linearity, and custom power supplies automatically adjusted the SiPM bias voltage to compensate for temperature-induced gain variations. A tagged calibration source, consisting of 240 nCi of 60Co embedded in plastic scintillator, was placed in the field of view and provided a known source of gamma rays to measure in flight. The SolCompT balloon payload was launched on 24 August 2014 from Fort Sumner, NM, and spent 3.75 h at a float altitude of 123,000 ft. The instrument performed well throughout the flight. After correcting for small ( 10%) residual gain variations, we measured an in-flight ToF resolution of 760 ps (FWHM). Advanced scintillators with SiPM readouts continue to show great promise for future gamma-ray instruments.

Hinode ``a new solar observatory in space''

NASA Astrophysics Data System (ADS)

Tsuneta, S.; Harra, L. K.; Masuda, S.

2009-05-01

Since its launch in September 2006, the Japan-US-UK solar physics satellite, Hinode, has continued its observation of the sun, sending back solar images of unprecedented clarity every day. Hinode is equipped with three telescopes, a visible light telescope, an X-ray telescope, and an extreme ultraviolet imaging spectrometer. The Hinode optical telescope has a large primary mirror measuring 50 centimeters in diameter and is the world's largest space telescope for observing the sun and its vector magnetic fields. The impact of Hinode as an optical telescope on solar physics is comparable to that of the Hubble Space Telescope on optical astronomy. While the optical telescope observes the sun's surface, the Hinode X-ray telescope captures images of the corona and the high-temperature flares that range between several million and several tens of millions of degrees. The telescope has captured coronal structures that are clearer than ever. The Hinode EUV imaging spectrometer possesses approximately ten times the sensitivity and four times the resolution of a similar instrument on the SOHO satellite. The source of energy for the sun is in the nuclear fusion reaction that takes place at its core. Here temperature drops closer to the surface, where the temperature measures about 6,000 degrees. Mysteriously, the temperature starts rising again above the surface, and the temperature of the corona is exceptionally high, several millions of degrees. It is as if water were boiling fiercely in a kettle placed on a stove with no fire, inconceivable as it may sound. The phenomenon is referred to as the coronal heating problem, and it is one of the major astronomical mysteries. The Hinode observatory was designed to solve this mystery. It is expected that Hinode would also provide clues to unraveling why strong magnetic fields are formed and how solar flares are triggered. An overview on the initial results from Hinode is presented. Dynamic video pictures captured by Hinode can be viewed on the website of the National Astronomical Observatory of Japan (NAOJ) at http://hinode.nao.ac.jp/index_e.shtml

Review of biased solar arraay. Plasma interaction studies

NASA Technical Reports Server (NTRS)

Stevens, N. J.

1981-01-01

The Solar Electric Propulsion System (SEPS) is proposed for a variety of space missions. Power for operating SEPS is obtained from large solar array wings capable of generating tens of kilowatts of power. To minimize resistive losses in the solar array bus lines, the array is designed to operate at voltages up to 400 volts. This use of high voltage can increase interactions between the biased solar cell interconnects and plasma environments. With thrusters operating, the system ground is maintained at space plasma potential which exposes large areas of the arrays at the operating voltages. This can increase interactions with both the natural and enhanced charged particle environments. Available data on interactions between biased solar array surfaces and plasma environments are summarized. The apparent relationship between collection phenomena and solar cell size and effects of array size on interactions are discussed. The impact of these interactions on SEPS performance is presented.

The Atacama Cosmology Telescope: High-Resolution Sunyaev-Zeldovich Array Observations of ACT SZE-Selected Clusters from the Equatorial Strip

NASA Technical Reports Server (NTRS)

Reese, Erik; Mroczkowski, Tony; Menateau, Felipe; Hilton, Matt; Sievers, Jonathan; Aguirre, Paula; Appel, John William; Baker, Andrew J.; Bond, J. Richard; Das, Sudeep;

Argus+: The Future of Wide-Field, Spectral-Line Imaging at 3-mm with the Green Bank Telescope

NASA Astrophysics Data System (ADS)

Maddalena, Ronald; Frayer, David; Lockman, Felix; O'Neil, Karen; White, Steven; Argus+ Collaboration

2018-01-01

The Robert C Byrd Green Bank Telescope has met its design goal of providing high-quality observations at 115 GHz. Observers also have access to the new, 16-pixel, 3-mm Argus receiver, which is providing high-dynamic range images over wide fields for the multitude of spectral lines between 85 and 115 GHz, including CO, 13CO, C18O, SiO, HCN, HCO+, HNC, N2H+, and CS. The small number of pixels in Argus limits its ability to map many of the most interesting objects whose extent exceeds many arc-minutes. The successful performance of Argus, and its modular design, demonstrates that receivers with many more pixels could be built for the GBT. A 12 x 12 array of the Argus design would have mapping speeds about nine times faster than Argus without suffering any degradation in performance for the outer pixels in the array. We present our plans to build the next-generation Argus instrument (Argus+) with 144-pixels, a footprint 5’x5’, and 7" resolution at 110 GHz. The project will be a collaboration between the Green Bank Observatory and university groups, who will supply key components. The key science drivers for Argus+ are studies of molecular filaments in the Milky Way, studies of molecular clouds in nearby galaxies, and the observations of rapidly evolving solar system objects.

Prototyping the graphical user interface for the operator of the Cherenkov Telescope Array

NASA Astrophysics Data System (ADS)

Sadeh, I.; Oya, I.; Schwarz, J.; Pietriga, E.

2016-07-01

The Cherenkov Telescope Array (CTA) is a planned gamma-ray observatory. CTA will incorporate about 100 imaging atmospheric Cherenkov telescopes (IACTs) at a Southern site, and about 20 in the North. Previous IACT experiments have used up to five telescopes. Subsequently, the design of a graphical user interface (GUI) for the operator of CTA involves new challenges. We present a GUI prototype, the concept for which is being developed in collaboration with experts from the field of Human-Computer Interaction (HCI). The prototype is based on Web technology; it incorporates a Python web server, Web Sockets and graphics generated with the d3.js Javascript library.

Use of ground-based telescopes in determining the composition of the surfaces of solar system objects

NASA Technical Reports Server (NTRS)

Mccord, T. B.; Adams, J. B.

1977-01-01

Recent evidence suggests that the way that the surfaces of the solar system objects reflect solar radiation is controlled by the composition and mineralogy of the surface materials. The way sunlight is reflected from the surface as a function of wavelength, i.e., the spectral reflectance, is the most important property. Laboratory efforts to use ground-based optical telescope measurements to determine the composition of the surfaces of the solar system objects are reviewed.

Investigation of small solar system objects with the space telescope

NASA Technical Reports Server (NTRS)

Morrison, D.

1979-01-01

The application of the space telescope (ST) to study small objects in the solar system in order to understand the birth and the early evolution of the solar system is discussed. The upper size limit of the small bodies is defined as approximately 5000 km and includes planetary satellites, planetary rings, asteroids, and comets.The use of the astronomical instruments aboard the ST, such as the faint object camera, ultraviolet and infrared spectrometers, and spectrophotometers, to study the small solar system objects is discussed.