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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 in about 5 years 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 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 NTRS2012

The James Webb Space Telescope: Extending the Science

The science objectives of the James Webb Space Telescope fall 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 to investigate the potential for life in those systems. These four science themes were used to establish the design requirements for the observatory and instrumentation. Since Webb's capabilities are unique, those science themes will remain relevant through launch and operations and goals contained within these themes will continue to guide the design and implementation choices for the mission. More recently, it has also become clear that Webb will make major contributions to other areas of research, including dark energy, dark matter, exoplanet characterization and Solar System objects. In this paper, I review the original four science themes and discuss how the scientific output of Webb will extend to these new areas of research.

Gardner, Jonathan P.↗
NASA NTRS2001

1999 Bioastronomy Meeting

The 6th Bioastronomy Conference, Bioastronomy '99: A New Era in Bioastronomy, was held at the Hapuna Prince Beach hotel on the Big Island of Hawaii from August 2-6, 1999. The series of previous Bioastronomy meetings have played an important role in integrating the broader interests and techniques of both astronomy and biology to understand the origin and evolution of living systems in the universe, and to generating a context for exploration in our solar system and in extrasolar planetary systems. The scope of these interdisciplinary fields is captured in the topics discussed at the meeting: organic molecules in interstellar and interplanetary space; origin and evolution of planetary systems; comets, asteroids, and other small bodies and their role in the origin and evolution of life; Earth as a living planet; extreme environments on Earth; origin of life; transport of life between planets; evolution of life and intelligence; detection and characterization of extrasolar planets; search for extraterrestrial technology and life; future missions; and public acceptance and support of scientific studies of life in the universe.

Meech, Karen J.↗
NASA NTRS2000

"1999 Bioastronomy Meeting"

The 6th Bioastronomy Conference, Bioastronomy '99: A New Era in Bioastronomy, was held at the Hapuna Prince Beach hotel on the Big Island of Hawaii from August 2-6, 1999. The series of previous Bioastronomy meetings have played an important role in integrating the broader interests and techniques of both astronomy and biology to understand the origin and evolution of living systems in the universe, and to generating a context for exploration in our solar system and in extrasolar planetary systems. The scope of these interdisciplinary fields is captured in the topics discussed at the meeting: organic molecules in interstellar and interplanetary space; origin and evolution of planetary systems; comets, asteroids, and other small bodies and their role in the origin and evolution of life; Earth as a living planet; extreme environments on Earth; origin of life; transport of life between planets; evolution of life and intelligence; detection and characterization of extrasolar planets; search for extraterrestrial technology and life; future missions; and public acceptance and support of scientific studies of life in the universe. This paper gives an overview summary of the conference and briefly highlights some of the themes discussed at the meeting.

Meech, Karen J.↗
NASA NTRS1979

Space optics; Proceedings of the Seminar, Huntsville, Ala., May 22-24, 1979

The seminar focused on infrared systems, the space telescope, new design for space astronomy, future earth resources systems, and planetary systems. Papers were presented on infrared astronomy satellite, infrared telescope on Spacelab 2, design alternatives for the Shuttle Infrared Telescope Facility, Spacelab 2 infrared telescope cryogenic system, geometrical theory of diffraction and telescope stray-light analysis, Space Telescope scientific instruments, faint-object spectrograph for the Space Telescope, light scattering from multilayer optics, bidirectional reflectance distribution function measurements of stray light suppression coatings for the Space Telescope, optical fabrication of a 60-in. mirror, interferogram analysis for space optics, nuclear-pumped lasers for space application, geophysical fluid flow experiment, coherent rays for optical astronomy in space, optical system with fiber-optical elements, and Pioneer-Venus solar flux radiometer.

Wyman, C. L.↗
NASA NTRS1981

Trends in unmanned planetary entry systems

Entry systems used in unmanned planetary exploration are discussed in terms of future missions and more complex demands made upon the design configurations of orbiters and atmospheric space probes. The presently on-going Galileo project involving a Jupiter orbiter and a probe of the Jovian atmosphere is mentioned, and the difficult entry requirements at a velocity of 48 km/sec and an angle of minus seven to minus 10 degrees into an atmosphere composed largely of hydrogen, are described. Re-entry parameters determined by the respective entry environment, type of entry approach (hyperbolic or elliptical orbit) entry velocity, and guidance technology are given attention. Aerobraking, involving relatively slow circularization of an initial elliptical orbit by repeated passes through the atmosphere, is investigated. Aerocapture, by which vehicles using controlled flight paths through the atmosphere, can go directly from a hyperbolic flyby trajectory to low circular orbit is described. Major attractions of aerobraking and aerocapture are analyzed in terms of modest technology needs and relatively small impact on spacecraft design.

French, J. R.↗
NASA NTRS2001

The Role of Giant Planets in Terrestrial Planet Formation

We present a progress report of a continuing study of the coupling between outer planetary system architecture and inner planetary system formation. Additional information is contained in the original extended abstract.

Levison, H. F.↗
NASA NTRS2004

JWST Town Meeting

The James Webb Space Telescope (JWST) Science Working Group has published the key scientific study areas for the mission: the end of the dark ages, the assembly of galaxies, the birth of stars and protoplanetary systems, and planetary systems and the origins of life. With these objectives establishing the major scientific capabilities of the observatory, the JWST Project has successfully completed major reviews of the telescope architecture and budget plan and has reached agreement on the contributions for all three international partners (NASA, ESA, and the Canadian Space Agency). Northrop Grumman Space Technologies (NGST) is the prime contractor responsible for the spacecraft, telescope, and integration. GSFC/NASA oversees the development and integration of the science instruments. The Space Telescope Science Institute is developing the JWST Science & Operations Center. The JWST will be launched to L2 2011 using an Ariane V. At this town hall, the mission's Project Scientists will present the technical and scientific status of the mission, concentrating on those areas that have changed over the last year. This will be an excellent opportunity to learn about JWST and catch up on the most recent developments. Questions from the audience will be welcomed. The town hall speakers will be John Mather, Peter Jakobsen, John Hutchings, and Peter Stockman.

Mather, John↗
NASA NTRS2012

James Webb Space Telescope: Large Deployable Cryogenic Telescope in Space

The James Webb Space Telescope (JWST) is an infrared space telescope designed to explore four major science themes: first light and reionization, the assembly of galaxies, the birth of stars and protoplanetary systems, and planetary systems and origins of life. JWST is a segmented architecture telescope with an aperture of 6.6 m. It will operate at cryogenic temperature (40 K), achieved via passive cooling, in an orbit about the Earth-Sun second Lagrange point (L2). Passive cooling is facilitated by means of a large sunshield that provides thermal isolation and protection from direct illumination from the Sun. The large size of the telescope and spacecraft systems require that they are stowed for launch in a configuration that fits the Ariane 5 fairing, and then deployed after launch. Routine wavefront sensing and control measurements are used to achieve phasing of the segmented primary mirror and initial alignment of the telescope. A suite of instruments will provide the capability to observe over a spectral range from 0.6- to 27-micron wavelengths with imaging and spectroscopic configurations. An overview is presented of the architecture and selected optical design features of JWST are described

Lightsey, Paul A.↗
NASA NTRS2004

Extrasolar Planet Inferometric Survey (EPIcS)

The discovery of the nature of the solar system was a crowning achievement of Renaissance science. The quest to evaluate the properties of extrasolar planetary systems is central to both the intellectual understanding of our origins and the cultural understanding of humanity's place in the Universe; thus it is appropriate that the goals and objectives of NASA's breakthrough Origins program emphasize the study of planetary systems, with a focus on the search for habitable planets. We propose an ambitious research program that will use SIM - the first major mission of the Origins program - to explore planetary systems in our Galactic neighborhood. Our program is a novel two-tiered SIM survey of nearby stars that exploits the capabilities of SIM to achieve two scientific objectives: (i) to identify Earth-like planets in habitable regions around nearby Sunlike stars: and (ii) to explore the nature and evolution of planetary systems in their full variety. The first of these objectives was recently recommended by the Astronomy and Astrophysics Survey Committee (the McKee-Taylor Committee) as a prerequisite for the development of the Terrestrial Planet Finder mission later in the decade. Our program combines this two-part survey with preparatory and contemporaneous research designed to maximize the scientific return from the limited and thus precious observing resources of SIM.

Shao, Michael↗
NASA NTRS1982

Vibration in Planetary Gear Systems with Unequal Planet Stiffnesses

An algorithm suitable for a minicomputer was developed for finding the natural frequencies and mode shapes of a planetary gear system which has unequal stiffnesses between the Sun/planet and planet/ring gear meshes. Mode shapes are represented in the form of graphical computer output that illustrates the lateral and rotational motion of the three coaxial gears and the planet gears. This procedure permits the analysis of gear trains utilizing nonuniform mesh conditions and user specified masses, stiffnesses, and boundary conditions. Numerical integration of the equations of motion for planetary gear systems indicates that this algorithm offers an efficient means of predicting operating speeds which may result in high dynamic tooth loads.

Frater, J. L.↗
NASA NTRS1981

Selection of a pump-fed propulsion system for planetary exploration missions

A study has been conducted to select the most desirable pump-fed propellant feed system approach for planetary spacecraft. Four systems, including two battery powered and two gas generator driven systems, were considered. Complete propulsion system schematics were developed, including preliminary detailed design of both the electric motor and the gas turbine pump drives. Utilizing a Figure-of-Merit system which included consideration for reliability, development risk, complexity and growth potential as well as weight, the advanced battery powered electric motor drive system was selected for continued development at JPL.

Auslander, T. W.↗
NASA NTRS1990

Extraterrestrial life in the universe

The possibility that life exists elsewhere in the universe, even in our own planetary system, has intrigued scientists, philosophers, and theologians for centuries. The spaceflight programs of NASA have provided much new information about our planetary neighbors and have put to rest some speculations about the existence of life on those planets or their satellites. However, there are still undetermined questions about the possibility of some form of life existing in the far distant past in our planetary system. Beyond our planetary system, the astronomical quest for scientific clues about life continues, largely via the radio telescope. Thus far there is no conclusive evidence. Here, some of the recent findings about our planetary neighbors are reviewed and the question about life elsewhere in the universe is addressed.

Graham, Robert W.↗
NASA NTRS1995

Carrier-less, anti-backlash planetary drive system

This invention relates to a carrier-less, anti-backlash planetary gear system that has an input sun gear, a force-balancing and planet-alignment 'speeder' gear above the sun gear, a split ring gear that has a fixed lower ring gear coaxial with the sun gear and a rotating upper ring gear also coaxial with the sun gear. A preload bolt is used for securing the split ring gears together. Within the split ring gear is an even number of planet gears between the split ring gear and the sun gear. Each planet gear consists of an upper planet gear, and lower planet gear with the upper and lower planet gears splined together and pushed apart by a spring which causes separation and relative twist between the upper and lower planet gears. The lower planet gear meshes with the input sun gear and the fixed ring gear while the upper planet gear is driven by the lower planet gear and meshes with the rotating ring gear.

Vranish, John M.↗