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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.

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NASA NTRS2011

The James Webb Space Telescope

The James Webb Space Telescope is the scientific successor to the Hubble and Spitzer Space Telescopes, and is currently the largest scientific project under construction in the United States. 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. Science with the James Webb Space Telescope falls into four themes. The End of the Dark Ages: First Light and Reionization theme seeks to identify the first luminous sources to form and to determine the ionization history of the universe. The Assembly of Galaxies theme seeks to determine how galaxies and the dark matter, gas, stars, metals, morphological structures, and black holes within them evolved from the epoch of reionization to the present. The Birth of Stars and Protoplanetary Systems theme seeks to unravel the birth and early evolution of stars, from infall onto dust-enshrouded protostars, to the genesis of planetary systems. The Planetary Systems and the Origins of Life theme seeks to determine the physical and chemical properties of planetary systems around nearby stars and of our own, and investigate the potential for life in those systems. Webb will have four instruments: The Near-Infrared Camera, the Near-Infrared multi-object Spectrograph, and the Tunable Filter Imager will cover the wavelength range 0.6 to 5 microns, while the Mid-Infrared Instrument will do both imaging and spectroscopy from 5 to 28.5 microns. I will conclude the talk with a description of recent technical progress in the construction of the observatory.

Gardner, Jonathan P.↗
NASA NTRSDate not supplied

The James Webb Space Telescope Mission Status

The James Webb Space Telescope (Webb) is a large, infrared space telescope that recently completed its on-orbit commissioning activities and will now embark on the first year of approved science. Its architecture includes many first-of-its-kind innovations for space, including a segmented primary mirror that is 6.6 m in diameter and a 5-layer sunshield used to passively cool the telescope and its four science instruments. Although Webb had an extensive test program, the system-level performance often relied on predictions based on integrated modeling, using conservative factors for the model uncertainties and primarily focusing on evaluating the performance requirements at end of life. A set of commissioning activities were designed for a system-level characterization of the performance. This proceeding will provide the status of the mission, including a discussion of the major events, on-orbit system performance, and early science highlights.

Michael McElwain↗
NASA NTRS2004

Extra Solar Planetary Imaging Coronagraph and Science Requirements for the James Webb Telescope Observatory

1) Extra solar planetary imaging coronagraph. Direct detection and characterization of Jovian planets, and other gas giants, in orbit around nearby stars is a necessary precursor to Terrestrial Planet Finder 0 in order to estimate the probability of Terrestrial planets in our stellar neighborhood. Ground based indirect methods are biased towards large close in Jovian planets in solar systems unlikely io harbor Earthlike planets. Thus to estimate the relative abundances of terrestrial planets and to determine optimal observing strategies for TPF a pathfinder mission would be desired. The Extra-Solar Planetary Imaging Coronagraph (EPIC) is such a pathfinder mission. Upto 83 stellar systems are accessible with a 1.5 meter unobscured telescope and coronagraph combination located at the Earth-Sun L2 point. Incorporating radiometric and angular resolution considerations show that Jovians could be directly detected (5 sigma) in the 0.5 - 1.0 micron band outside of an inner working distance of 5/D with integration times of -10 - 100 hours per observation. The primary considerations for a planet imager are optical wavefront quality due to manufacturing, alignment, structural and thermal considerations. pointing stability and control, and manufacturability of coronagraphic masks and stops to increase the planetary-to- stellar contrast and mitigate against straylight. Previously proposed coronagraphic concepts are driven to extreme tolerances. however. we have developed and studied a mission, telescope and coronagraphic detection concept, which is achievable in the time frame of a Discovery class NASA mission. 2) Science requirements for the James Webb Space Telescope observatory. The James Webb Space Observatory (JWST) is an infrared observatory, which will be launched in 201 1 to an orbit at L2. JWST is a segmented, 18 mirror segment telescope with a diameter of 6.5 meters, and a clear aperture of 25 mA2. The telescope is designed to conduct imaging and spectroscopic observations from 0.6-27 microns. The primary mirror find and understand predicted first light objects, observe galaxies back to their earliest precursors so that we can understand their growth and evolution, unravel the birth and early evolution of stars and planetary systems, and study planetary systems and the origins of life. In this paper we discuss the science goals for JWST in the context of the performance requirements they levy on the observatory.

Clampin, Mark↗
NASA NTRS2007

Wavefront Aberrations Due to Alignment and Figure Compensation of the NASA James Webb Space Telescope

This viewgraph presentation describes wavefront aberrations due to the alignment and improper compensation of the NASA James Webb Space Telescope. The contents include: 1) James Webb Space Telescope (JWST); 2) Optical design of JWST; 3) Alignment Observables for JWST; 4) Low order Zernike Polynomials; 5) PM SM Ability to Target Low Order Aberrations; 6) Compensator definitions and Modes; 7) Field impact from compensation; 8) PM align error compensated by PM figure; 9) PM align error compensated by SM alignment; 10) SM align error compensated by PM figure; 11) SM figure error compensated by SM alignment; 12) Worst Case Pupil Maps; 13) Worst Case Pupil Maps at BEST FOCUS; 14) Field impact from compensation (+/- 1 arcmin FOV); and 15) Concluding Remarks.

Howard, Joseph↗
NASA NTRS2009

The James Webb Space Telescope

The James Webb Space Telescope is the successor to Hubble and will be launched into space in 2013. It is not only bigger than Hubble, but is cooled to 225 degrees below zero Centigrade in order to detect the infrared light, or heat radiation, from distant stars and galaxies. I will discuss how Webb's scientific discoveries will take us beyond Hubble, and describe some of the recent progress we have made in its construction.

Gardner, Jonathan↗
NASA NTRS2009

A Scientific Revolution: The Hubble and James Webb Space Telescopes

Astronomy is going through a scientific revolution, responding to a flood of data from the Hubble Space Telescope, other space missions, and large telescopes on the ground. In this talk, I will discuss the top 10 astronomical discoveries of the last 10 years, and the role that space telescopes have played in those discoveries. The next decade looks equally bright with the newly refurbished Hubble and the promise of its successor, the James Webb Space Telescope. I will describe how Hubble was upgraded and how and why we are building Webb.

Gardner, Jonathan P.↗
NASA NTRS2011

A Scientific Revolution: The Hubble and James Webb Space Telescopes

Astronomy is going through a scientific revolution, responding to a flood of data from the Hubble Space Telescope, other space missions, and large telescopes on the ground. In this talk, I will discuss some of the most important astronomical discoveries of the last 10 years, and the role that space telescopes have played in those discoveries. The next decade looks equally bright with the newly refurbished Hubble and the promise of its successor, the James Webb Space Telescope. I will describe how Hubble was upgraded and how and why we are building Webb.

Gardner, Jonathan↗
NASA NTRS2011

A Scientific Revolution: the Hubble and James Webb Space Telescopes

Astronomy is going through a scientific revolution, responding to a flood of data from the Hubble Space Telescope, other space missions, and large telescopes on the ground. In this talk, I will discuss some of the most important astronomical discoveries of the last 10 years, and the role that space telescopes have played in those discoveries. The next decade looks equally bright with the newly refurbished Hubble and the promise of its successor, the James Webb Space Telescope. I will describe how Hubble was upgraded and how and why we are building Webb.

Gardner, Jonathan P.↗
NASA NTRS2012

A Scientific Revolution: the Hubble and James Webb Space Telescopes

Astronomy is going through a scientific revolution, responding to a flood of data from the Hubble Space Telescope, other space missions, and large telescopes on the ground. In this talk, I will discuss some of the most important astronomical discoveries of the last IO years, and the role that space telescopes have played in those discoveries. The next decade looks equally bright with the newly refurbished Hubble and the promise of its successor, the James Webb Space Telescope. I will describe how Hubble was upgraded and how and why we are building Webb.

Gardner, Jonathan P.↗
NASA NTRS2012

Building the James Webb Space Telescope

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.

Gardner, Jonathan P.↗
NASA NTRS2012

James Webb Space Telescope Optical Telescope Element Mirror Development History and Results

In a little under a decade, the James Webb Space Telescope (JWST) program has designed, manufactured, assembled and tested 21 flight beryllium mirrors for the James Webb Space Telescope Optical Telescope Element. This paper will summarize the mirror development history starting with the selection of beryllium as the mirror material and ending with the final test results. It will provide an overview of the technological roadmap and schedules and the key challenges that were overcome. It will also provide a summary or the key tests that were performed and the results of these tests.

Feinber, Lee D.↗
NASA NTRS2012

Science with the James Webb Space Telescope

The James Webb Space Telescope is the scientific successor to the Hubble and Spitzer Space Telescopes. It will be a large (6.6m) cold (50K) telescope launched into orbit around the second Earth-Sun lagrange point. It is a partnership of NASA with the European and Canadian Space Agencies. The science goals for JWST include the formation of the first stars and galaxies in the early universe; the chemical, morphological and dynamical buildup of galaxies and the formation of stars and planetary systems. Recently, the goals have expanded to include studies of dark energy, dark matter, active galactic nuclei, exoplanets and Solar System objects. Webb will have four instruments: The Near-Infrared Camera, the Near-Infrared multi-object Spectrograph, and the Near-Infrared Imager and Slitiess Spectrograph will cover the wavelength range 0.6 to 5 microns, while the Mid-Infrared Instrument will do both imaging and spectroscopy from 5 to 28.5 microns. The observatory is confirmed for launch in 2018; the design is complete and it is in its construction phase. Recent progress includes the completion of the mirrors, the delivery of the first flight instrument(s) and the start of the integration and test phase.

Gardner, Jonathan P.↗
NASA NTRS2012

Science Operations with the James Webb Space Telescope

The James Webb Space Telescope (JWST) will be a powerful space observatory whose four science instruments will deliver rich imaging and multiplexed spectroscopic datasets to the astronomical and planetary science communities. The ground segment for JWST, now being designed and built, will carry out JWST's science operations. The ground segment includes: (1) software that the scientific community will use to propose and specify new observations; (2) software that will schedule both science and calibration observations in a way that optimizes observing efficiency while managing the accumulation of momentum; (3) the infrastructure to regularly measure and maintain the telescope's wavefront; (4) orbit determination, ranging, and tracking; (5) communication via the Deep Space Network to command the observatory and retrieve scientific data; (6) onboard scripts that execute each observing program in an event-driven fashion, with occasional interruptions for targets of opportunity or time-critical observations; and (7) a system that processes and calibrates the data into science ready products, automatically recalibrates when calibrations improve, and archives the data for timely access by the principal investigator and later worldwide access by the scientific community. This ground system builds on experience from operating the Hubble Space Telescope, while solving challenges that are unique to the James Webb Space Telescope. In this paper, we describe the elements of the JWST ground system, how it will work operationally from the perspective of the observatory itself, and how a typical user will interact with the system to turn his/her idea into scientific discovery.

Rigby, Jane↗
NASA NTRS2012

The James Webb Space Telescope

The James Webb Space Telescope is the scientific successor to the Hubble and Spitzer Space Telescopes. It will be a large (6.6m) cold (SDK) telescope launched into orbit around the second Earth-Sun Lagrange point. It is a partnership of NASA with the European and Canadian Space Agencies. The science goals for JWST include the formation of the first stars and galaxies in the early universe; the chemical, morphological and dynamical buildup of galaxies and the formation of stars and planetary systems. Recently, the goals have expanded to include studies of dark energy, dark matter, active galactic nuclei, exoplanets and Solar System objects. Webb will have four instruments: The Near-Infrared Camera, the Near-Infrared multi-object Spectrograph, and the Near-Infrared Imager and Slitless Spectrograph will cover the wavelength range 0.6 to S microns, while the Mid-Infrared Instrument will do both imaging and spectroscopy from 5 to 28.5 microns. The observatory is confirmed for launch in 2018; the design is complete and it is in its construction phase. Recent progress includes the completion of the mirrors, the delivery of the first flight instruments and the start of the integration and test phase.

Gardner, Jonathan P.↗
NASA NTRS2016

Creating the Thermal Environment for Safely Testing the James Webb Space Telescope at the Johnson Space Center's Chamber A

Chamber A is the largest thermal vacuum chamber at the Johnson Space Center and is one of the largest space environment chambers in the world. The chamber is 19.8 m (65 ft) in diameter and 36.6 m (120 ft) tall and is equipped with cryogenic liquid nitrogen panels (shrouds) and gaseous helium shrouds to create a simulated space environment. The chamber was originally built to support testing of the Apollo Service and Command Module for lunar missions, but underwent major modifications to be able to test the James Webb Space Telescope in a simulated deep space environment. To date seven tests have been performed in preparation of testing the flight optics for the James Webb Space Telescope (JWST). Each test has had a uniquie thermal profile and set of thermal requirements for cooling down and warming up, controlling contamination, and releasing condensed air. These range from temperatures from 335K to 15K, with tight uniformity and controllability for maintining thermal stability and pressure control. One unique requirement for two test was structurally proof loading hardware by creating thermal gradients at specific temperatures. This paper will discuss the thermal requirements and goals of the tests, the original requirements of the chamber thermal systems for planned operation, and how the new requirements were met by the team using the hardware, system flexiblilty, and engineering creativity. It will also discuss the mistakes and successes to meet the unique goals, especially when meeting the thermal proof load.

Homan, Jonathan L.↗
NASA NTRS2017

Application of Molecular Adsorber Coatings in Chamber A for the James Webb Space Telescope

As a coating made of highly porous zeolite materials, the Molecular Adsorber Coating (MAC) was developed to capture outgassed molecular contaminants, such as hydrocarbons and silicones. For spaceflight applications, the adsorptive capabilities of the coating can alleviate on-orbit outgassing concerns on or near sensitive surfaces and instruments within the spacecraft. Similarly, this sprayable paint technology has proven to be significantly beneficial for ground-based space applications, in particular, for vacuum chamber environments. This presentation describes the application of the MAC technology for the James Webb Space Telescope (JWST) at NASA Johnson Space Center (JSC). The coating was used as a mitigation tool to entrap outgassed contaminants, specifically silicone-based diffusion pump oil, from within JSCs cryogenic optical vacuum chamber test facility called Chamber A. This presentation summarizes the background, fabrication, installation, chemical analysis test results, and future plans for the MAC technology, which was effectively used to protect the JWST test equipment from vacuum chamber contamination. As a coating made of highly porous zeolite materials, the Molecular Adsorber Coating (MAC) was developed to capture outgassed molecular contaminants, such as hydrocarbons and silicones. For spaceflight applications, the adsorptive capabilities of the coating can alleviate on-orbit outgassing concerns on or near sensitive surfaces and instruments within the spacecraft. Similarly, this sprayable paint technology has proven to be significantly beneficial for ground-based space applications, in particular, for vacuum chamber environments. This presentation describes the application of the MAC technology for the James Webb Space Telescope (JWST) at NASA Johnson Space Center (JSC). The coating was used as a mitigation tool to entrap outgassed contaminants, specifically silicone-based diffusion pump oil, from within JSCs cryogenic optical vacuum chamber test facility called Chamber A. This presentation summarizes the background, fabrication, installation, chemical analysis test results, and future plans for the MAC technology, which was effectively used to protect the JWST test equipment from vacuum chamber contamination.

molecular contamination↗
NASA NTRS2016

Modernization of NASA's Johnson Space Center Chamber: A Payload Transport Rail System to Support Cryogenic Vacuum Optical Testing of the James Webb Space Telescope (JWST)

NASA is the mission lead for the James Webb Space Telescope (JWST), the next of the "Great Observatories", scheduled for launch in 2018. It is directly responsible for the integration and test (I&T) program that will culminate in an end-to-end cryo vacuum optical test of the flight telescope and instrument module in Chamber A at NASA Johnson Space Center. Historic Chamber A is the largest thermal vacuum chamber at Johnson Space Center and one of the largest space simulation chambers in the world. Chamber A has undergone a major modernization effort to support the deep cryogenic, vacuum and cleanliness requirements for testing the JWST. This paper describe the challenges of developing, integrating and modifying new payload rails capable of transporting payloads within the thermal vacuum chamber up to 65,000 pounds. Ambient and Cryogenic Operations required to configure for testing will be explained. Lastly review historical payload configurations stretching from the Apollo program era to current James Webb Space Telescope testing.

Garcia, Sam↗