SEARCH · Search NASA

Results for “cryogenic space telescope”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 145 records · Page 8

All sources NASA NTRS DOE OSTI

NASA NTRS2010

The James Webb Space Telescope Mission

The James Webb Space Telescope (JWST) is a large aperture, cryogenic, infrared-optimized space observatory under development by NASA for launch in 2014. The European and Canadian Space Agencies are mission partners. JWST will find and study the first galaxies that formed in the early universe, peer through dusty clouds to see AGN environments and stars forming planetary systems at high spatial resolution. The breakthrough capabilities of JWST will enable new studies of star formation and evolution in the Milky Way, including the Galactic Center, nearby galaxies, and the early universe. JWST's instruments are designed to work primarily in the infrared range of 1 - 28 microns, with some capability in the visible. JWST will have a segmented primary mirror, approximately 6.5 meters in diameter, and will be diffraction-limited at wavelength of 2 microns (0.1 arcsec resolution). The JWST observatory will be placed in a L2 orbit by an Ariane 5 launch vehicle provided by ESA. The observatory is designed for a 5-year prime science mission, with propellant for 10 years of science operations. The instruments will provide broad- and narrow-band imaging, coronography, and multi-object and integral-field spectroscopy (spectral resolution of 100 to 3,000) across the 1 - 28 micron wavelength range. Science and mission operations will be conducted from the Space Telescope Science Institute in Baltimore, Maryland.

Sonneborn, George↗

NASA NTRS2011

The James Webb Space Telescope (JWST)

The James Webb Space Telescope (JWST) is a large aperture, cryogenic, infrared-optimized space observatory under construction by NASA for launch later this decade. The European and Canadian Space Agencies are mission partners. JWST will find and study the first galaxies that formed in the early universe and peer through dusty clouds to see star and planet formation at high spatial resolution. The breakthrough capabilities of JWST will enable new studies of star formation and evolution in the Milky Way, including the Galactic Center, nearby galaxies, and the early universe. JWST will have a segmented primary mirror, approximately 6.5 meters in diameter, and will be diffraction-limited at 2 microns. The JWST observatory will be placed in a L2 orbit by an Ariane 5 launch vehicle provided by ESA. The observatory is designed for a 5- year prime science mission, with consumables for 10 years of science operations.

Sonneborn, George↗

NASA NTRS2011

The James Webb Space Telescope: Science and Mission Status

Sonneborn, George↗

NASA NTRS2002

The AstroBiology Explorer (ABE) MIDEX Mission Concept: Using Infrared Spectroscopy to Identify Organic Molecules in Space

One of the principal means by which organic compounds are detected and identified in space is by infrared spectroscopy. Past IR studies (telescopic and laboratory) have demonstrated that much of the carbon in the interstellar medium (ISM) is in complex organic species of a variety of types, but the distribution, abundance, and evolutionary relationships of these materials are not well understood. The Astrobiology Explorer (ABE) is a MIDEAST mission concept designed to conduct IR spectroscopic observations to detect and identify these materials to address outstanding important problems in astrobiology, astrochemistry, and astrophysics. Systematic studies include the observation of planetary nebulae and stellar outflows, protostellar objects, Solar System Objects, and galaxies, and multiple lines of sight through dense molecular clouds and the diffuse ISM. ABE will also search for evidence of D enrichment in complex molecules in all these environments. The mission is currently under study at NASA's Ames Research Center in collaboration with Ball Aerospace and Technologies Corp. ABE is a cryogenically-cooled 60 cm diameter space telescope equipped with 3 cryogenic cross-dispersed spectrographs that share a single common slit. The 3 spectrometers each measure single spectral octaves (2.5-5, 5-10, 10-20 microns) and together cover the entire 2.5 - 20 micron region simultaneously. The spectrometers use state-of-the-art 1024x1024 pixel detectors, with a single InSb array for the 2.5-5 micron region and two Si:As arrays for the 5-10 and 10-20 micron regions. The spectral resolution is wavelength dependent but is greater than 2000 across the entire spectral range. ABE would operate in a heliocentric, Earth drift-away orbit and is designed to take maximum advantage of this environment for cooling, thermal stability, and mission lifetime. ABE would have a core science mission lasting approximately 1.5 years.

Sandford, Scott A.↗

NASA NTRS2007

Development of a Cryogenic Thermal Distortion Measurement Facility for Testing the James Webb Space Telescope Instrument Support Integration Module 2-D Test Assemblies

The James Webb Space Telescope Instrument Support Integration Module (ISIM) is being designed and developed at the Goddard Space Flight Center. The ISM Thermal Distortion Testing (ITDT) program was started with the primary objective to validate the ISM mechanical design process. The ITDT effort seeks to establish confidence and demonstrate the ability to predict thermal distortion in composite structures at cryogenic temperatures using solid element models. This-program's goal is to better ensure that ISIM meets all the mechanical and structural requirements by using test results to verify or improve structural modeling techniques. The first step to accomplish the ITDT objectives was to design, and then construct solid element models of a series 2-D test assemblies that represent critical building blocks of the ISIM structure. Second, the actual test assemblies consisting of composite tubes and invar end fittings were fabricated and tested for thermal distortion. This paper presents the development of the GSFC Cryo Distortion Measurement Facility (CDMF) to meet the requirements of the ISIM 2-D test. assemblies, and other future ISIM testing needs. The CDMF provides efficient cooling with both a single, and two-stage cryo-cooler. Temperature uniformity of the test assemblies during thermal transients and at steady state is accomplished by using sapphire windows for all of the optical ports on the radiation shields and by using .thermal straps to cool the test assemblies. Numerical thermal models of the test assemblies were used to predict the temperature uniformity of the parts during cooldown and at steady state. Results of these models are compared to actual temperature data from the tests. Temperature sensors with a 0.25K precision were used to insure that test assembly gradients did not exceed 2K lateral, and 4K axially. The thermal distortions of two assemblies were measured during six thermal cycles from 320K to 35K using laser interferometers. The standard deviation for all of the distortion measurements is less than 0.5 microns, which falls within the ISIM requirement of 3 microns.

Miller, Franklin↗

NASA NTRSDate not supplied

TARDIS: Acelerating TVAC Transitions

"Large spacecraft components, including instruments, require long durations to transition between temperature plateaus during TVAC (Thermal Vacuum) testing. This is especially true for cryogenic instruments whose operating temperatures are extremely low. Due to the T4 relation, using radiative heat transfer alone for temperature transitions to cryogenic temperatures is extremely time consuming. The Wide Field Instrument (WFI) on the upcoming Roman Space Telescope (RST) is one such cryogenic instrument. The TARDIS (Thermal Acceleration Rate Device for Integrated Systems) is a heat switch device which will be used during the WFI TVAC test campaign in order to decrease WFI transition times. Over the course of the planned ___ week WFI instrument-level TVAC testing, TARDIS is being estimated to save ___ days of test time. By reducing the total TVAC duration, TARDIS is providing significant cost and schedule savings to the RST WFI project. Based on the successful design of the LUCY L’Ralph AZQ Heat Switch, TARDIS can provide both high conductivity for temperature transitions and low conductivity Zero-Q for thermal balances. This is achieved by use of a mechanical clamp heat switch and actively controlled cold plate. Using this method, TARDIS is estimated to be able to change its conductance from approximately 0.20 W/K to ¬¬0.002 W/K, for a turndown ratio of 100. This paper details the design, analysis, and testing of TARDIS. It also previews the operation of TARDIS in the upcoming WFI TVAC test campaign. "

TVAC, Heat Switch↗

NASA NTRS1978

Infrared Astronomical Satellite /IRAS/ and Shuttle Infrared Telescope Facility /SIRTF/ - Implications of scientific objectives on focal plane sensitivity requirements

The full potential of infrared astronomy can be realized only through observations made with space-based telescopes cooled to cryogenic temperatures. The paper outlines the scientific mission, system description, and focal plane requirements for two cryogenic telescopes: the Infrared Astronomical Satellite (IRAS) and the Shuttle Infrared Telescope Facility (SIRTF). IRAS, a 60-cm superfluid-helium-cooled telescope system, will perform a one-year 8-120-micron IR sky survey; it will provide results of high reliability and sensitivity, produce the first complete survey data for the 30-120-micron region, and fill in missing portions (spectrally and spatially) of previous surveys short of 30 microns; its focal plane assembly is being designed to approach background-limited performance with an array of 62 discrete detectors. The SIRTF design will allow detailed follow-up studies in the 1-1000-micron range with a 116-160-cm observatory-class instrument. The Shuttle sortie capability introduces the unique SIRTF concept of an easily refurbishable or replaceable focal plane instrument complement in an orbiting cryogenic telescope.

Mccreight, C. R.↗

NASA NTRS1992

Space Cryogenics Workshop, 10th, Cleveland, OH, June 18-20, 1991, Proceedings

The present workshop on cryogenics discusses the anomalous on-orbit behavior of the Cosmic Background Explorer Dewar, the SHOOT orbital operations, cooling options for Astromag, and space IR telescope facility mission and cryogenic design. Attention is given to the design of a spaceworthy adiabatic demagnetization refrigerator, the evaluation of metal hydride compressors for applications in Joule-Thomson cryocoolers, diaphragm Stirling cryocooler developments, and a computer simulation model for Stirling refrigerators. Topics addressed include low-gravity thermal stratification of liquid helium on SHOOT, a screening program to select a resin for gravity probe-B composites, a simplified generic cryostat thermal model for predicting cryogen mass and lifetime, and the effect of gas mass flux on cryogenic liquid jet breakup. Also discussed are damping criteria for thermal acoustic oscillations in slush and liquid hydrogen systems, an STS-based cryogenic fluid management experiment, and the design and testing of a cryogenic mixer pump.

Source record↗

NASA NTRS1993

Arrays: The Heart and Soul of SIRTIF

This paper describes the status of NASA's Space Infrared Telescope Facility (SIRTF) program. SIRTF will be a cryogenically cooled observatory for infrared astronomy from space and is planned for launch early in the next decade. It will be the first cryogenic observatory to make extensive use of the powerful infrared detector array technology discussed at this conference. We summarize a newly developed SIRTF mission concept and show how the availability of detector arrays has shaped the scientific rationale for SIRTF, and how the arrays themselves have become part of the definition of the SIRTF mission.

SIRTF infrared detector arrays Space Infrared Tele↗

NASA NTRS2011

Measuring the Cryogenic Optical Alignment Between the Telescope Element and the Instruments Module of the James Webb Space Telescope

The alignment between the Aft Optical Subsystem (AOS) and the Integrated Science Instruments Module (ISIM) is non-adjustable in orbit, so the alignment must be carefully verified in a cryogenic vacuum environment prior to launch. Optical point source locations calibrated by optical metrology instruments are imaged through the AOS onto the Science Instruments to determine focal, lateral, and clock angle alignment. The pupil image of the AOS is overlaid onto the pupil image of the NIRCam to determine the tip and tilt alignment. In addition, an image from fiducial lights at the Primary Mirror checks the pupil alignment between the telescope entrance pupil, the telescope pupil mask, and the NIRCam aperture stop. The image positions are combined to determine the relative alignment between the Optical Telescope Element (OTE) and the ISIM in all six degrees of freedom with corresponding alignment uncertainties. Uncertainties in the position of focused images of the test sources and images from the pupils are derived from sensitivities of an optical model of the system and the Science Instrument sensing capability. Additional uncertainty in the pupil alignment measurement is due to uncertainty in the analytical removal of gravity effects that simulate the on-orbit alignment environment.

Whitman, Tony↗

NASA NTRS2013

Cryogenic Optical Performance of a Lightweighted Mirror Assembly for Future Space Astronomical Telescopes: Correlating Optical Test Results and Thermal Optical Model

A 43cm diameter stacked core mirror demonstrator was interferometrically tested at room temperature down to 250 degrees Kelvin for thermal deformation. The 2.5m radius of curvature spherical mirror assembly was constructed by low temperature fusing three abrasive waterjet core sections between two CNC pocket milled face sheets. The 93% lightweighted Corning ULE® mirror assembly represents the current state of the art for future UV, optical, near IR space telescopes. During the multiple thermal test cycles, test results of interferometric test, thermal IR images of the front face were recorded in order to validate thermal optical model.

Eng, Ron↗

NASA NTRS2018

Thermal Control of Boundaries for JWST Infrared Tests in Cryogenic Vacuum Configuration

In 2017, the combined Optical Telescope Element and Integrated Science Instrument Module (OTIS) of the James Webb Space Telescope (JWST) underwent functional testing and optical metrology verification under cryogenic vacuum conditions in Chamber A at the Johnson Space Center (JSC). Testing the infrared Science Instruments and OTIS optics below 50 degrees Kelvin required an environment architecture that comprehensively controlled the temperature and energy path of every seam and penetration in the over 1100 m2 of Chamber A helium shroud surfaces as well as the Ground Support Equipment (GSE) inside it. This paper outlines the design and implementation of thermal closeouts, thermal anchoring systems for electrical cables, and thermal control systems around room-temperature optical metrology equipment inside the helium shroud. It also details lessons learned from the repeated implementation and testing of these environmental control systems throughout the JWST Pathfinder test campaign.

Huguet, Jesse A.↗

NASA NTRS2018

Thermal Control of Boundaries for JWST Infrared Tests in Cryogenic Vacuum Configuration

In 2017, the combined Optical Telescope Element and Integrated Science Instrument Module (OTIS) of the James Webb Space Telescope (JWST) underwent functional testing and optical metrology verification under cryogenic vacuum conditions in Chamber A at the Johnson Space Center (JSC). Testing the infrared Science Instruments and OTIS optics below 50 K required an environment architecture that comprehensively controlled the temperature and energy path of every seam and penetration in the over 1100 sq m of Chamber A helium shroud surfaces as well as the Ground Support Equipment (GSE) inside it. This paper outlines the design and implementation of thermal closeouts, thermal anchoring systems for electrical cables, and thermal control systems around room-temperature optical metrology equipment inside the helium shroud. It also details lessons learned from the repeated implementation and testing of these environmental control systems throughout the JWST Pathfinder test campaign.

Huguet, Jesse A.↗

NASA NTRS2014

Design and Lessons Learned on the Development of a Cryogenic Pupil Select Mechanism Used in the Testing and Calibration of the Integrated Science Instrument Module (ISIM) on the James Webb Space Telescope (JWST)

Calibration and testing of the instruments on the Integrated Science Instrument Module (ISIM) of the James Webb Space Telescope (JWST) is being performed by the use of a cryogenic, full-field, optical simulator that was constructed for this purpose. The Pupil Select Mechanism (PSM) assembly is one of several mechanisms and optical elements that compose the Optical Telescope Element SIMulator, or OSIM. The PSM allows for several optical elements to be inserted into the optical plane of OSIM, introducing a variety of aberrations, distortions, obscurations, and other calibration states into the pupil plane. The following discussion focuses on the details of the design evolution, analysis, build, and test of this mechanism along with the challenges associated with creating a sub arc-minute positioning mechanism operating in an extreme cryogenic environment. In addition, difficult challenges in the control system design will be discussed including the incorporation of closed-loop feedback control into a system that was designed to operate in an open-loop fashion.

Testing↗

NASA NTRS2014

Design and Lessons Learned on the Development of a Cryogenic Pupil Select Mechanism used in the Testing and Calibration of the Integrated Science Instrument Module (ISIM) on the James Webb Space Telescope (JWST)

Mitchell, Alissa↗

NASA NTRS2002

The AstroBiology Explorer (ABE) MIDEX Mission Concept: Using Infrared Spectroscopy to Identify Organic Molecules in Space

One of the principal means by which organic compounds are detected and identified in space is by infrared spectroscopy. Past IR telescopic and laboratory studies have shown that much of the carbon in the interstellar medium (ISM) is in complex organic species but the distribution, abundance and evolutionary relationships of these materials are not well understood. The Astrobiology Explorer (ABE) is a MIDEX mission concept designed to conduct IR spectroscopic observations to detect and identify these materials and address outstanding problems in astrobiology, astrochemistry, and astrophysics. ABE's core science program includes observations of planetary nebulae and stellar outflows, protostellar objects, Solar System objects, and galaxies, and lines of sight through dense molecular clouds and the diffuse ISM. ABE is a cryogenically-cooled 60 cm diameter space telescope equipped with 3 cross-dispersed R-2000 spectrometers that share a single common slit. Each spectrometer measures one spectral octave and together cover the entire 2.5-20 micron region simultaneously. The spectrometers use state-of-the-art InSb and Si:As 1024x1024 pixel detectors. ABE would operate in a heliocentric, Earth drift-away orbit and have a core science mission lasting approximately 1.5 years. ABE is currently under study at NASA's Ames Research Center in collaboration with Ball Aerospace and Technologies Corp.

Sandford, Scott A.↗

NASA NTRS1987

Space Infrared Telescope Facility (SIRTF) design and thermal analysis

The design and performance characteristics of an observatory are compared with those of a storage dewar. The critical design technologies required to increase cryogen dewar lifetime are discussed. In particular, outer shell temperature, vapor cooled shields, multilayer insulation performance, and tank support systems are analyzed to assess their impact on cryogen lifetime for both the observatory and the storage dewar. The cryogen lifetime and cryogen mass loss rate of the Space Infrared Telescope Facility (SIRTF) are compared with that of the Infrared Astronomy Satellite and the Cosmic Background Explorer Satellite. A 0.1 percent mass loss per day of superfluid helium dewar can be designed using current state-of-the-art dewar technology. Space-based liquid hydrogen and liquid oxygen tanks can be designed for a 5-year lifetime.

Lee, Jeffrey H.↗

NASA NTRS1993

Passive Cooling For Large Infrared Telescopes

Conceptual passive-cooling technique enables very large infrared telescope in vacuum of outer space cooled to below 20 K without using cryogen. Telescope orbiting Earth at high altitude of around 100,000 km. Scheme also offers very small gradient of temperature across primary telescope reflector, so thermal distortions smaller; accuracy of surface figure of reflector significantly enhanced. Passive-cooling technique also applied to building of very large cryostats and to development of very large sun shields in traditional manner, and some elements of technique adapted for current small observatories.

Lin, Edward I.↗