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1,973 Matching Results

Start Over Decade 1990-1999

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(open access)

Nuclear technologies for Moon and Mars exploration

Nuclear technologies are essential to successful Moon and Mars exploration and settlements. Applications can take the form of nuclear propulsion for transport of crews and cargo to Mars and the Moon; surface power for habitats and base power; power for human spacecraft to Mars; shielding and life science understanding for protection against natural solar and cosmic radiations; radioisotopes for sterilization, medicine, testing, and power; and resources for the benefits of Earth. 5 refs., 9 figs., 3 tabs.

Date: January 1, 1991

Creator: Buden, D.

Object Type: Article

System: The UNT Digital Library

(open access)

Nuclear power systems for Lunar and Mars exploration

Initial studies of a variety of mission scenarios for the new Space Exploration Initiative, and the technologies necessary to enable or significantly enhance them, have identified the development of advanced space power systems - whether solar, chemical or nuclear - to be of prime importance. Lightweight, compact, reliable power systems for planetary rovers and a variety of surface vehicles, utility surface power, and power for advanced propulsion systems were identified as critical needs for these missions. This paper discusses these mission scenarios, the concomitant power system requirements; the power system options considered and identifies the significant potential benefits of nuclear power for meeting the power needs of the above applications.

Date: September 1, 1994

Creator: Sovie, R. J. & Bozek, J. M.

Object Type: Article

System: The UNT Digital Library

(open access)

Exploring the Moon and Mars: Choices for the Nation

This report, the result of an assessment of the potential for automation and robotics technology to assist in the exploration of the Moon and Mars, raises a number of issues related to the goals of the U.S. civilian space program. Among other things, the report discusses how greater attention to automation and robotics technologies could contribute to U.S. space exploration efforts.

Date: July 1991

Creator: United States. Congress. Office of Technology Assessment.

Object Type: Report

System: The UNT Digital Library

captions transcript

[News Clip: Mars VO]

B-roll footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

Date: October 16, 1996, 5:00 p.m.

Creator: KXAS-TV (Television station : Fort Worth, Tex.)

Object Type: Video

System: The UNT Digital Library

(open access)

WET MARS: plentiful, readily-available martian water and its implications

Water and its major constituent, oxygen, in large specific quantities are essential for maintenance of human life. Providing them in adequate quantities is widely believed to be a major challenge for human Mars exploration and settlement. The Martian regolith isn't known to bear either water or hydrogen, the ice-rich Martian polar regions are thermally inhospitable, and the measured water content of Mars' thin atmosphere represents a layer of liquid water of average thickness only about 1% that of the Moon: {approximately}0.001 cm. Crucially, however, the atmospheric Martian water inventory is advected to everyplace on Mars by meteorological phenomena, so that the few cubic kilometers of liquid water-equivalent in the atmosphere are available most anywhere when, merely for the effort of condensing it. Well-engineered apparatus deployed essentially anywhere on Mars can condense water from the atmosphere in daily quantities not much smaller than its own mass, rejecting into space from radiators deployed over the local terrain the water's heat-of-condensation and the heat from non-ideality of the equipment's operation. Thus, an optimized, photovoltaically-powered 0.3 ton water-condensing system could strip 40 tons of water each year from {approximately}10{sup 4} times this mass of thin, dry Martian air. Given a 480 set I{sub sp} …

Date: August 12, 1999

Creator: Hyde, R.; Ishikawa, M.; Nuckolls, J.; Whitehead, J. & Wood, L.

Object Type: Article

System: The UNT Digital Library

(open access)

Surplus weapons-grade plutonium: a resource for exploring and terraforming Mars

With the end of the Cold War, greater than 100 metric tons (MT) of weapons-grade plutonium (WGPu) have become surplus to defense needs in the United States and the Former Soviet Union. This paper is a proposal for an option for WGPu disposition, i.e., use of the plutonium as a fuel for nuclear reactors for Mars exploration and eventual terraforming. WGPu was used in nuclear weapons because it has a much smaller critical mass than highly enriched uranium, allowing lighter weapons with consequent longer ranges. Similarly, WGPu reactors would also require smaller amounts of fuel to attain a critical mass, making the reactor much lighter overall and resulting in large savings in launch costs. The greater than 100 MT of WGPu would generate about 1000 billion kilowatt hours of heat energy, much of which could be converted into electricity. The waste heat would also be useful to a Martian outpost or colony. A potential way of getting the WGPu reactors into space is a large gas gun like that being developed at the Lawrence Livermore National Laboratory to orbit materials by achieving high velocity at the surface, greatly reducing launch costs and enhancing reliability. Reactor components would be launched on …

Date: December 31, 1996

Creator: Muscatello, A.C. & Houts, M.G.

Object Type: Article

System: The UNT Digital Library

(open access)

Nuclear rockets: High-performance propulsion for Mars

A new impetus to manned Mars exploration was introduced by President Bush in his Space Exploration Initiative. This has led, in turn, to a renewed interest in high-thrust nuclear thermal rocket propulsion (NTP). The purpose of this report is to give a brief tutorial introduction to NTP and provide a basic understanding of some of the technical issues in the realization of an operational NTP engine. Fundamental physical principles are outlined from which a variety of qualitative advantages of NTP over chemical propulsion systems derive, and quantitative performance comparisons are presented for illustrative Mars missions. Key technologies are described for a representative solid-core heat-exchanger class of engine, based on the extensive development work in the Rover and NERVA nuclear rocket programs (1955 to 1973). The most driving technology, fuel development, is discussed in some detail for these systems. Essential highlights are presented for the 19 full-scale reactor and engine tests performed in these programs. On the basis of these tests, the practicality of graphite-based nuclear rocket engines was established. Finally, several higher-performance advanced concepts are discussed. These have received considerable attention, but have not, as yet, developed enough credibility to receive large-scale development.

Date: May 1, 1994

Creator: Watson, C. W.

Object Type: Report

System: The UNT Digital Library

(open access)

An Integrated Mission Approach to the Space Exploration Initiative Will Ensure Success

The direction of the American space program, as defined by President Bush and the National Commission on Space, is to expand human presence into the solar system. Landing an American on Mars by the 50th anniversary of the Apollo 11 lunar landing is the goal. This challenge has produced a level of excitement among young Americans not seen for nearly three decades. The exploration and settlement of the space frontier will occupy the creative thoughts and energies of generations of Americans well into the next century. The return of Americans to the moon and beyond must be viewed as a national effort with strong public support if it is to become a reality. Key to making this an actuality is the mission approach selected. Developing a permanent presence in space requires a continual stepping outward from Earth in a logical progressive manner. If we seriously plan to go and to stay, then not only must we plan what we are to do and how we are to do it, we must address the logistic support infrastructure that will allow us to stay there once we arrive. A fully integrated approach to mission planning is needed if the Space Exploration Initiative …

Date: October 1, 1990

Creator: Coomes, E. P.; Dagle, J. E.; Bamberger, J. A. & Noffsinger, K. E.

Object Type: Article

System: The UNT Digital Library

(open access)

Structural analyses of the JPL Mars Pathfinder impact

The purpose of this paper is to demonstrate that finite element analysis can be used in the design process for high performance fabric structures. These structures exhibit extreme geometric nonlinearity; specifically, the contact and interaction of fabric surfaces with the large deformation which necessarily results from membrane structures introduces great complexity to analyses of this type. All of these features are demonstrated here in the analysis of the Jet Propulsion Laboratory (JPL) Mars Pathfinder impact onto Mars. This lander system uses airbags to envelope the lander experiment package, protecting it with large deformation upon contact. Results from the analysis show the stress in the fabric airbags, forces in the internal tendon support system, forces in the latches and hinges which allow the lander to deploy after impact, and deceleration of the lander components. All of these results provide the JPL engineers with design guidance for the success of this novel lander system.

Date: December 31, 1994

Creator: Gwinn, K.W.

Object Type: Article

System: The UNT Digital Library

captions transcript

[News Clip: Space Exploration]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story about new space inventions to explore Mars in the Johnson Space Center in Houston.

Date: 1998

Creator: KXAS-TV (Television station : Fort Worth, Tex.)

Object Type: Video

System: The UNT Digital Library

(open access)

Design and Analysis of RTGs for Solar and Martian Exploration Missions

The paper described the results of design, analysis and spacecraft integration studies of Radioisotope Thermoelectric Generators (RTGs) for three unmanned space exploration missions. The three missions, consisting of the Mars Rover and Sample Return (MRSR) mission, the Solar Probe mission, and the Mars Global Net work (MGN) mission, are under study by the Jet Propulsion Laboratory (JPL) for the U.S. National Aeronautics and Space Administration (NASA). The NASA/JPL mission studies are supported by the U.S. Department of Energy's Office of Special Applications (DOE/OSA), which has commissioned Fairchild Space Company to carry out the required RTG design studies.

Date: May 1, 1990

Creator: Schock, Alfred

Object Type: Report

System: The UNT Digital Library

(open access)

Exploration Mission Enhancements Possible With Power Beaming. [Space Applications Power Beaming]

A key factor in the exploration and development of the space frontier is the availability of energy where and when it is needed. Currently all space satellites and platforms include self-contained power systems that supply the energy necessary to accomplish mission objectives. An alternative approach is to couple advanced high power system with energy beam transmitters and energy receivers to form an infrastructure of a space power utility where a central power system provides power to multiple users. Major space activities, such as low Earth orbit space commercialization and the colonization of the Moon or Mars, would benefit significantly from a central power generation and transmission system. This paper describes the power-beaming concept and system components as applied to space power generation and distribution in support of the Space Exploration Initiative. Beam-power scenarios are discussed including commonality of systems and hardware with cargo transport vehicles, power beaming from orbit to stationary and mobile users on the Lunar and Mars surfaces, and other surface applications. 6 refs.

Date: October 1, 1990

Creator: Bamberger, J. A.; Coomes, E. P. & Segna, D. R.

Object Type: Article

System: The UNT Digital Library

(open access)

WET MARS: Plentiful, Readily-Available Martian Water and its Implications

Water and its major constituent, oxygen, in large specific quantities are essential for maintenance of human life. Providing them in adequate quantities is widely believed to be a major challenge for human exploration and settlement of Mars. The Martian regolith isn't known to bear either water or hydrogen, the ice-rich Martian polar regions are thermally inhospitable, and the measured water content of Mars' thin atmosphere represents a layer of liquid water of average thickness only {approx}1% that available on the Moon, or {approx}0.001 cm. Crucially, however, the atmospheric Martian water inventory is advected meteorologically to everyplace on Mars, so that the few cubic kilometers of liquid water-equivalent in the atmosphere are available anywhere when, merely for the effort of condensing it. Well-engineered apparatus deployed essentially anywhere on Mars can condense water from the atmosphere in daily quantities not much smaller than its own mass, rejecting into space from radiators deployed over the local terrain the water's heat-of-condensation and the heat from non-ideality of the equipment's operation. Thus, an optimized, photovoltaically-powered water-condensing system of {approx}0.3 tons mass could strip 40 tons of water each year from {approx} 10{sup 4} times this mass of thin, dry Martian air. Given a 490 set …

Date: September 14, 1999

Creator: Hyde, R.; Ishikawa, M.; Nuckolls, J.; Whitehead, J. & Wood, L.

Object Type: Article

System: The UNT Digital Library

(open access)

Design of a Nuclear-Powered Rover for Lunar or Martian Exploration

To perform more advanced studies on the surface of the moon or Mars, a rover must provide long-term power ({ge}10 kW{sub e}). However, a majority of rovers in the past have been designed for much lower power levels (i.e., on the order of watts) or for shorter operating periods using stored power. Thus, more advanced systems are required to generate additional power. One possible design for a more highly powered rover involves using a nuclear reactor to supply energy to the rover and material from the surface of the moon or Mars to shield the electronics from high neutron fluxes and gamma doses. Typically, one of the main disadvantages of using a nuclear-powered rover is that the required shielding would be heavy and expensive to include as part of the payload on a mission. Obtaining most of the required shielding material from the surface of the moon or Mars would reduce the cost of the mission and still provide the necessary power. This paper describes the basic design of a rover that uses the Heatpipe Power System (HPS) as an energy source, including the shielding and reactor control issues associated with the design. It also discusses briefly the amount of …

Date: August 1, 1998

Creator: Trellue, Holly R.; Trautner, Rachelle; Houts, Michael G.; Poston, David I.; Giovig, Kenji; Baca, Justin A. et al.

Object Type: Article

System: The UNT Digital Library

(open access)

New vision solar system exploration missions study: Analysis of the use of biomodal space nuclear power systems to support outer solar system exploration missions. Final report

This report presents the results of an analysis of the capability of nuclear bimodal systems to perform outer solar system exploration missions. Missions of interest include orbiter mission s to Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto. An initial technology baseline consisting of a NEBA 10 kWe, 1000 N thrust, 850 s, 1500 kg bimodal system was selected, and its performance examined against a data base for trajectories to outer solar system planetary destinations to select optimal direct and gravity assisted trajectories for study. A conceptual design for a common bimodal spacecraft capable of performing missions to all the planetary destinations was developed and made the basis of end to end mission designs for orbiter missions to Jupiter, Saturn, and Neptune. Concepts for microspacecraft capable of probing Jupiter`s atmosphere and exploring Titan were also developed. All mission designs considered use the Atlas 2AS for launch. It is shown that the bimodal nuclear power and propulsion system offers many attractive option for planetary missions, including both conventional planetary missions in which all instruments are carried by a single primary orbiting spacecraft, and unconventional missions in which the primary spacecraft acts as a carrier, relay, and mother ship for a fleet of …

Date: December 8, 1995

Creator: unknown

Object Type: Report

System: The UNT Digital Library

(open access)

Advanced hybrid nuclear propulsion Mars mission performance enhancement

Nuclear electric propulsion (NEP), compared with chemical and nuclear thermal propulsion (NTP), can effectively deliver the same mass to Mars using much less propellant, consequently requiring less mass delivered to Earth orbit. The lower thrust of NEP requires a spiral trajectory near planetary bodies, which significantly increases the travel time. Although the total travel time is long, the portion of the flight time spent during interplanetary transfer is shorter, because the vehicle is thrusting for much longer periods of time. This has led to the supposition that NEP, although very attractive for cargo missions, is not suitable for piloted missions to Mars. However, with the application of a hybrid approach to propulsion, the benefits of NEP can be utilized while drastically reducing the overall travel time required. Development of a dual-mode system, which utilizes high-thrust NTP to propel the spacecraft from the planetary gravitational influence and low-thrust NEP to accelerate in interplanetary space, eliminates the spiral trajectory and results in a much faster transit time than could be obtained by either NEP or NTP alone. This results in a mission profile with a lower initial mass in low Earth orbit. In addition, the propulsion system would have the capability to …

Date: February 1, 1992

Creator: Dagle, J. E.; Noffsinger, K. E. & Segna, D. R.

Object Type: Article

System: The UNT Digital Library

(open access)

A low-alpha nuclear electric propulsion system for lunar and Mars missions

The advantages of using electric propulsion are well-known in the aerospace community. The high specific impulse and, therefore, lower propellant requirements make it a very attractive propulsion option for the Space Exploration Initiative (SEI). Recent studies have shown that nuclear electric propulsion (NEP) is not only attractive for the transport of cargo but that fast piloted missions to Mars are possible as well, with alphas on the order of 7.5 kg/kW. An advanced NEP system with a specific power (alpha) of 2.5 kg/kW or less would significantly enhance the manned mission option of NEP by reducing the trip time even further. This paper describes an advanced system that combines the PEGASUS Drive with systems of the Rotating Multimegawatt Boiling Liquid Metal (RMBLR) power system that was developed as part of the DOE multimegawatt program and just recently declassified. In its original configuration, the PEGASUS Drive was a 10-MWe propulsion system. The RMBLR was a 20-MW electric system. By combining the two, a second-generation PEGASUS Drive can be developed with an alpha less than 2.5 kg/kW. This paper will address the technology advancements incorporated into the PEGASUS Drive, the analysis of a fast piloted mission and an unmanned cargo transport Mars …

Date: January 1, 1992

Creator: Coomes, E. P. & Dagle, J. E.

Object Type: Article

System: The UNT Digital Library

(open access)

An integrated mission planning approach for the space exploration initiative

A fully integrated energy-based approach to mission planning is needed if the Space Exploration Initiative (SEI) is to succeed. Such an approach would reduce the number of new systems and technologies requiring development. The resultant horizontal commonality of systems and hardware would reduce the direct economic impact of SEI and provide an economic benefit by greatly enhancing our international technical competitiveness through technology spin-offs and through the resulting early return on investment. Integrated planning and close interagency cooperation must occur if the SEI is to achieve its goal of expanding the human presence into the solar system and be an affordable endeavor. An energy-based mission planning approach gives each mission planner the needed power, yet preserves the individuality of mission requirements and objectives while reducing the concessions mission planners must make. This approach may even expand the mission options available and enhance mission activities.

Date: January 1, 1992

Creator: Coomes, E. P.; Dagle, J. E.; Bamberger, J. A. & Noffsinger, K. E.

Object Type: Article

System: The UNT Digital Library

(open access)

Advanced hybrid nuclear propulsion Mars mission performance enhancement

Date: February 1, 1992

Creator: Dagle, J. E.; Noffsinger, K. E. & Segna, D. R.

Object Type: Article

System: The UNT Digital Library

(open access)

An Integrated Mission Planning Approach for the Space Exploration Initiative

Date: January 1, 1992

Creator: Coomes, E. P.; Dagle, J. E.; Bamberger, J. A. & Noffsinger, K. E.

Object Type: Article

System: The UNT Digital Library

(open access)

Fiber optic chemical sensors on Mars

A fiber optic chemical sensing instrument is described that will measure the reactivity of the martian soil and atmosphere. The self- contained instrument monitors reflectivity changes in reactive thin films caused by chemical reactions with the martian soil or atmosphere. Data from over 200 separate thin-film-coated optical fibers are recorded simultaneously. This fiber optic sensing technology has many advantages for planetary exploration and monitoring applications on manned spacecraft, in addition to many practical terrestrial uses.

Date: December 31, 1993

Creator: Butler, M. A.; Ricco, A. J.; Grunthaner, F. J. & Lane, A. L.

Object Type: Article

System: The UNT Digital Library

(open access)

Power system requirements and selection for the space exploration initiative

The Space Exploration Initiative (SEI) seeks to reestablish a US program of manned and unmanned space exploration. The President has called for a program which includes a space station element, a manned habitation of the moon, and a human exploration of Mars. The NASA Synthesis Group has developed four significantly different architectures for the SEI program. One key element of a space exploration effort is the power required to support the missions. The Power Speciality Team of the Synthesis Group was tasked with assessing and evaluating the power requirements and candidate power technologies for such missions. Inputs to the effort came from existing NASA studies as well as other governments agency inputs such as those from DOD and DOE. In addition, there were industry and university briefings and results of solicitations from the AIAA and the general public as part of the NASA outreach effort. Because of the variety of power needs in the SEI program, there will be a need for multiple power system technologies including solar, nuclear and electrochemical. Due to the high rocket masses required to propel payloads to the moon and beyond to Mars, there is great emphasis placed on the need for high power density …

Date: January 1, 1991

Creator: Biringer, K.L. (Sandia National Labs., Albuquerque, NM (United States)); Bartine, D.E. (Oak Ridge National Lab., TN (United States)); Buden, D. (Idaho National Engineering Lab., Idaho Falls, ID (United States)); Foreman, J. (Naval Research Lab., Washington, DC (United States)) & Harrison, S. (Strategic Defense Initiative Organization, Washington, DC (United States))

Object Type: Article

System: The UNT Digital Library

(open access)

Nuclear data needs for the space exploration initiative

On July 20, 1989, the President of the United States announced a new direction for the US Space Program. The new Space Exploration Initiative (SEI) is intended to emplace a permanent base on the Lunar surface and a manned outpost on the Mars surface by 2019. In order to achieve this ambitious challenge, new, innovative and robust technologies will have to be developed to support crew operations. Nuclear power and propulsion have been recognized as technologies that are at least mission enhancing and, in some scenarios, mission enabling. Because of the extreme operating conditions present in a nuclear rocket core, accurate modeling of the rocket will require cross section data sets which do not currently exist. In order to successfully achieve the goals of the SEI, major obstacles inherent in long duration space travel will have to be overcome. One of these obstacles is the radiation environment to which the astronauts will be exposed. In general, an unshielded crew will be exposed to roughly one REM per week in free space. For missions to Mars, the total dose could exceed more than one-half the total allowed lifetime level. Shielding of the crew may be possible, but accurate assessments of shield …

Date: January 1, 1991

Creator: Howe, S.D. & Auchampaugh, G.

Object Type: Article

System: The UNT Digital Library

(open access)

A Case for Mars: A Case for Nuclear Thermal Rockets

It is now possible to make general comparisons of candidate propulsion systems for human exploration of Mars. Preliminary review indicates that the propulsion system most likely to meet all mission requirements is the Nuclear Thermal Rocket (NTR). Advanced cryogenic chemical propulsion systems achieve a maximum specific impulse (Isp) of about 470 seconds. The Nuclear Engine for Rocket Vehicle Application (NERVA) program of the 1960's built engines with Isp's of about 825 seconds. Performance of an NTR depends on achievable materials temperatures, but materials has progressed significantly since the 1960's. Also, some of the current research undertaken to improve chemical rocket performance, such as aerobraking or schemes to minify payload, applies to an NTR as well, although it is not essential. The NTR is reusable, and can be developed into a complete space transportation system. Only 3--4% of the nuclear fuel would be used in a Mars mission, and an engine can be used until about 40% of the fuel is expended. Nuclear thermal rockets can take mankind to the moon, to Mars, and beyond, but development must begin now. There is potential for orderly growth into nuclear concepts far beyond NERVA. Using chemical propulsion for lunar missions and delaying NTR …

Date: January 1, 1990

Creator: Neuman, J. E.; Van Haaften, D. H. & Madsen, W. W.

Object Type: Article

System: The UNT Digital Library

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