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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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At least 307 records · Page 17
All sourcesNASA NTRSDOE OSTI
NASA NTRS2004

Deep space environments for human exploration

Mission scenarios outside the Earth's protective magnetic shield are being studied. Included are high usage assets in the near-Earth environment for casual trips, for research, and for commercial/operational platforms, in which career exposures will be multi-mission determined over the astronaut's lifetime. The operational platforms will serve as launching points for deep space exploration missions, characterized by a single long-duration mission during the astronaut's career. The exploration beyond these operational platforms will include missions to planets, asteroids, and planetary satellites. The interplanetary environment is evaluated using convective diffusion theory. Local environments for each celestial body are modeled by using results from the most recent targeted spacecraft, and integrated into the design environments. Design scenarios are then evaluated for these missions. The underlying assumptions in arriving at the model environments and their impact on mission exposures within various shield materials will be discussed. Published by Elsevier Ltd on behalf of COSPAR.

NASA Center LaRC↗
NASA NTRS2010

WISE and the Dusty Universe

The Wide-field Infrared Survey is a medium class Explorer mission that was launched onl4Dec 2009. WISE should detect hundreds of millions of stars and galaxies, including millions of ULIRGS and QSOs; hundreds of thousands of asteroids; and hundreds of cold brown dwarfs. The telescope cover was ejected on 29 Dec 2009 and the all-sky survey started on 14 Jan 2010. WISE takes more the 7000 framesets per day, with each frameset covering 0.6 square degrees in four bands centered at 3.4, 4.6, 12 and 22 microns. WISE is well-suited to the discovery of brown dwarfs, ultraluminous infrared galaxies, and near-Earth objects. With an angular resolution of 6 arcsecouds at 12 microns, a 5(sigma) point-source sensitivity of around 1 mJy at 12 microns and 6 mJy at 22 microns, and coverage of over 99% of the sky, WISE also provides a powerful database for the study of the dusty ISM in our own galaxy. A preliminary release of WISE data will be made available to the community 6 months after the end of the cryogenic survey, or about May 2011. The final data release will be 11 months later, about April 2012.

Benford, Dominic J.↗
NASA NTRS1991

Utilization of space resources: A historical view

While widely accepted today, the use of non-Earth resources in official space planning circles has been long in coming. Popular and governmental acceptance of using extraterrestrial resources, be they asteroids, comets, or other celestial bodies are highlighted. Particular emphasis is placed on those individuals, such as the late Dandridge Cole, who pioneered early discussion and thought on the topic over a period of several decades. The evolution of using extraterrestrial resources in governmental space policy, such as NASA's Outlook for Space (1976) and Pioneering the Space Frontier (1986) is reviewed. Put forward is the view that a redefinition of resources of near-Earth space may be warranted, particularly in consideration of using high vacuum, solar radiation, and magnetospheric phenomenon for experimentation and application purposes. Lastly, a prospective look at public reaction to utilizing space resources is presented.

David, Leonard W.↗
NASA NTRS2005

Orbit Modification of Earth-Crossing Asteroids/Comets Using Rendezvous Spacecraft and Laser Ablation

This report describes the approach and results of an end-to-end simulation to deflect a long-period comet (LPC) by using a rapid rendezvous spacecraft and laser ablation system. The laser energy required for providing sufficient deflection DELTA V and an analysis of possible intercept/rendezvous spacecraft trajectories are studied in this analysis. These problems minimize a weighted sum of the flight time and required propellant by using an advanced propulsion system. The optimal thrust-vector history and propellant mass to use are found in order to transfer a spacecraft from the Earth to a targeted celestial object. One goal of this analysis is to formulate an optimization problem for intercept/rendezvous spacecraft trajectories. One approach to alter the trajectory of the object in a highly controlled manner is to use pulsed laser ablative propulsion. A sufficiently intense laser pulse ablates the surface of a near-Earth object (NEO) by causing plasma blowoff. The momentum change from a single laser pulse is very small. However, the cumulative effect is very effective because the laser can interact with the object over long periods of time. The laser ablation technique can overcome the mass penalties associated with other nondisruptive approaches because no propellant is required to generate the DELTA V (the material of the celestial object is the propellant source). Additionally, laser ablation is effective against a wide range of surface materials and does not require any landing or physical attachment to the object. For diverting distant asteroids and comets, the power and optical requirements of a laser ablation system on or near the Earth may be too extreme to contemplate in the next few decades. A hybrid solution would be for a spacecraft to carry a laser as a payload to a particular celestial body. The spacecraft would require an advanced propulsion system capable of rapid rendezvous with the object and an extremely powerful electrical generator, which is likely needed for the propulsion system as well. The spacecraft would station-keep with the object at a small standoff distance while the laser ablation is performed.

Park, Sang-Young↗
NASA NTRS2006

LAD-C: A large area debris collector on the ISS

The Large Area Debris Collector (LAD-C) is a 10 sq m aerogel and acoustic sensor system under development by the U.S. Naval Research Laboratory (NRL) with main collaboration from the NASA Orbital Debris Program Office at Johnson Space Center, JAXA Institute of Space and Astronautical Science (ISAS), Chiba University (Japan), ESA Space Debris Office, University of California at Berkeley, and University of Kent at Canterbury (UK). The U.S. Department of Defense (DoD) Space Test Program (STP) has assumed the responsibility for having the system manifested and deployed on the International Space Station (ISS), and then having it retrieved and returned to Earth after one to two years. LAD-C will attempt to utilize the ISS as a scientific platform to characterize the near-Earth meteoroid and orbital debris environment in the size regime where little data exist. In addition to meteoroid and orbital debris sample return, the acoustic sensors will record impact time, location, signal strength, and acoustic waveform data of the largest collected samples. A good time-dependent meteoroid and orbital debris flux estimate can be derived. Analysis of the data will also enable potential source identification of some of the collected samples. This dynamical link can be combined with laboratory composition analysis of impact residuals extracted from aerogel to further our understanding of orbital debris population, and the sources of meteoroids, asteroids and comets.

Liou, J.-C.↗
NASA NTRS2010

Athena: Providing Insight into the History of the Universe

The American Institute for Aeronautics and Astronautics has provided a Request for Proposal which calls for a manned mission to a Near-Earth Object. It is the goal of Team COLBERT to respond to their request by providing a reusable system that can be implemented as a solid stepping stone for future manned trips to Mars and beyond. Despite Team COLBERT consisting of only students in Aerospace Engineering, in order to achieve this feat, the team must employ the use of Systems Engineering. Tools and processes from Systems Engineering will provide quantitative and semi-quantitative tools for making design decisions and evaluating items such as budgets and schedules. This paper will provide an in-depth look at some of the Systems Engineering processes employed and will step through the design process of a Human Asteroid Exploration System.

Murphy, Gloria A.↗
NASA NTRS2008

Near Earth Object (NEO) Mitigation Options Using Exploration Technologies

This presentation considers the use of new launch vehicles in defense against near-Earth objects, building upon expertise in launch vehicle and spacecraft design, astronomy and planetary science and missile defense. This work also seeks to demonstrate the synergy needed between architectures for human/robotic exploration initiatives and planetary defense. Three different mitigation operations were baselined for this study--nuclear standoff explosion, kinetic interceptor, and solar collector--however, these are not the only viable options. The design and predicted performance of each of these methods is discussed and compared. It is determined that the nuclear interceptor option can deflect NEOs of smaller size (100-500 m) with 2 years or more time before impact, and larger NEOs with 5 or more years warning; kinetic interceptors may be effective for deflection of asteroids up to 300-400 m but require 8-10 years warning time; and, solar collectors may be able to deflect NEOs up to 1 km if issues pertaining to long operation can be overcome. Ares I and Ares V vehicles show sufficient performance to enable the development of a near-term categorization and mitigation architecture.

Adams, Robert B.↗
NASA NTRS1977

Developing space occupancy - Perspectives on NASA future space program planning

Potential future manned space flight missions for the time after the development of the space transportation system with the space shuttle are considered, taking into account a sequence of activities concerning a gradually increasing penetration of space by man. The activities are related to the permanent occupancy of near-earth space, the permanent occupancy of near-moon space, the full self-sufficiency of man in earth-moon space, and the permanent occupancy of heliocentric space. Attention is given to Mars orbiting stations, the exploration of the asteroids, comet exploration, planet engineering programs, heliocentric orbit installation, the evolution of the earth orbit space community, space industrialization technology, lunar base development, and evolutionary paths to far-future space endeavors.

Von Puttkamer, J.↗
NASA NTRS1978

Summer Workshop on Near-Earth Resources

The possible large scale use of extraterrestrial resources was addressed, either to construct structures in space or to return to Earth as supplements for terrestrial resources. To that end, various specific recommendations were made by the participants in the summer study on near-Earth resources, held at La Jolla, California, 6 to 13 August, 1977. The Moon and Earth-approaching asteroids were considered. Summaries are included of what is known about their compositions and what needs to be learned, along with recommendations for missions designed to provide the needed data. Tentative schedules for these projects are also offered.

Arnold, J. R.↗
NASA NTRS1982

Requirements for a space station

Near-term requirements which will guide the design of a manned space station in near-earth orbit are considered. A primary focus will be establishing a base for astronomical observations which demand long term integration times. Earth observation systems such as the thematic mappers and SAR can be utilized by a free flyer in sunsynchronous orbit. Biological experiments can be carried out only with pressurized modules, ultimately large enough for humans habitation. At first, expendables would be ferried up from earth, while over time the space station would become a closed-loop system. An orbital transfer vehicle is necessary for the repair of satellites stationed in higher energy orbits. The operations of the station would include checking out communications satellites before boost into GEO. Finally, the station would be the final staging point for interplanetary and/or asteroid intercept missions.

Herman, D. H.↗
NASA NTRS1982

Geological implications of impacts of large asteroids and comets on the earth

The present conference discusses such topics as large object fluxes in near-earth space and the probabilities of terrestrial impacts, the geological record of impacts, dynamics modeling for large body impacts on continents and oceans, physical, chemical, and biological models of large impacts' atmospheric effects, dispersed impact ejecta and their signatures, general considerations concerning mass biological extinctions, the Cretaceous/Tertiary boundary event, geochemical signatures in the stratigraphic record, and other phanerozoic events. Attention is given to terrestrial impact rates for long- and short-period comets, estimates of crater size for large body impact, a first-order estimate of shock heating and vaporization in oceanic impacts, atmospheric effects in the first few minutes after an impact, a feasibility test for biogeographic extinction, and the planktonic and dinosaur extinctions.

Silver, L. T.↗
NASA NTRS1992

Asteroid and comet orbits using radar data

For the 30 asteroids and 4 comets for which radar astrometric data were given by Ostro (1991), orbits have been computed using both the radar and the existing optical measurements. The techniques required to process radar data in orbit determination solutions are outlined, and future radar observation opportunities for asteroids and comets are identified. For asteroids and comets that have only short intervals of optical astrometric data, the additional use of only a few radar observations allows a far more accurate extrapolation of their future motions. The use of radar data can often ensure an object's successful recovery at future earth returns and greatly assist efforts in monitoring the motions of the rapidly growing population of known near-earth objects, including their future close-earth approaches.

Yeomans, D. K.↗
NASA NTRS1992

Relationship of E-type Apollo asteroid 3103 (1982 BB) to the enstatite achondrite meteorites and the Hungaria asteroids

Visible and near-IR observations are reported which confirm that Apollo asteroid 3103 (1982 BB) is a high-albedo E-type object with a reflectance spectrum consistent with the iron-free silicates, primarily enstatite, present in the aubrites. Visible and thermal IR light curves indicate that 3103 is an elongated object with no evidence of substantial surface albedo variations. It is presently in an orbital resonance with earth and is probably a relatively long-lived member of the earth-approaching population. This is consistent with the relatively long cosmic ray exposure ages of the aubrites compared to other stony meteorites. The fall geometries of the aubrites are consistent with their being derived from 3103. The ubiquitous brecciated nature of the aubrites and the indications of a single parent body for nearly all these meteorite suggest that 3103 is the sole near-earth parent body of this meteorite type.

Gaffey, Michael J.↗
NASA NTRS2003

A New Time-dependent Model for the Martian Radiation Environment

Manned space activities have been until present time limited to the near-Earth environment, most of them to low Earth orbit (LEO) scenarios, with only some of the Apollo missions targeted to the Moon. In current times most human exploration and development of space (HEDS) activities are related to the development of the International Space Station (ISS), and therefore take place in the LEO environment. A natural extension of HEDS activities will be going beyond LEO, and reach asteroids, Mars, Jupiter, Saturn, the Kuiper belt and the outskirts of the Solar System. Such long journeys onboard spacecraft outside the protective umbrella of the geomagnetic field will require higher levels of protection from the radiation environment found in the deep space for both astronauts and equipment. So, it is important to have available a tool for radiation shielding which takes into account the radiation environments found all along the interplanetary space and at the different bodies encountered in the Solar System. Moreover, the radiation protection is one of the two NASA highest concerns and priorities. A tool integrating different radiation environments with shielding computation techniques especially tailored for deep space mission scenario is instrumental in view of this exigency. In view of manned missions targeted to Mars, for which radiation exposure is one of the greatest problems and challenges to be tackled, it is of fundamental importance to have available a tool which allows to know which are the particle flux and spectra at any time at any point of the Martian surface. With this goal in mind, a new model for the radiation environment to be found on the planet Mars due to Galactic Cosmic Rays (GCR) has been developed. Solar modulated primary particles rescaled for Mars conditions are transported within the Martian atmosphere, with temporal properties modeled with variable timescales, down to the surface, with altitude and backscattering patterns taken into account. The tool allows analysis for manned Mars landing missions, as well as planetary science studies, e.g. subsurface water and volatile inventory studies. This Mars environmental model is available through the SIREST website, a project of NASA Langley Research Center.

G De Angelis↗
NASA NTRS1999

NASA's Near-Earth Object Office

Near-Earth Objects (NEOs) are scientifically interesting remnants of the early solar system formation process, accessible resources for the raw materials necessary for colonizing the inner solar system in the next century, and objects that can threaten life on Earth.

Near Earth Objects Comets Asteroids↗
NASA NTRS2007

P/2006 HR30 (Siding Spring): A Low-activity Comet in Near-Earth Space

The low cometary activity of P/2006 HR30 (Siding Spring) allowed a unique opportunity to study the nucleus of a periodic comet while near perihelion. P/2006 HR30 was originally targeted as a potential extinct comet, and we measured spectral reflectance and dust production using long-slit CCD spectroscopy and wide-field imaging obtained at the Palomar Mountain 200 inch telescope on 2006 August 3 and 4. The dust production Afp = 19.7 +/- 0.4 cm and mass-loss rate Q(dust) 4.1 +/- 0.1 kg/sec of the comet were approximately 2 orders of magnitude dust less than 1P/Halley at similar heliocentric distance. The VRI colors derived from the spectral reflectance were compared to Kuiper Belt objects, Centaurs, and other cometary nuclei. We found that the spectrum of P/2006 HR30 was consistent with other comets. However, the outer solar system bodies have a color distribution statistically distinct from cometary nuclei. It is our conjecture that cometary activity, most likely the reaccretion of ejected cometary dust, tends to moderate and mute the visible colors of the surface of cometary nuclei.

comets↗