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27,337 Matching Results
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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
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
The Heatpipe-Operated Mars Exploration Reactor (HOMER)
Devises an attractive space fission system that can be developed quickly and affordably.
Date:
October 1, 2000
Creator:
Poston, David I.
Object Type:
Article
System:
The UNT Digital Library
The Mars Hopper: a radioisotope powered, impulse driven, long-range, long-lived mobile platform for exploration of Mars
Planetary exploration mission requirements are becoming more demanding. Due to the increasing cost, the missions that provide mobile platforms that can acquire data at multiple locations are becoming more attractive. Wheeled vehicles such as the MER rovers have proven extremely capable but have very limited range and cannot traverse rugged terrain. Flying vehicles such as balloons and airplanes have been proposed but are problematic due to the very thin atmospheric pressure and the strong, dusty winds present on Mars. The Center for Space Nuclear Research has designed an instrumented platform that can acquire detailed data at hundreds of locations during its lifetime - a Mars Hopper. The Mars Hopper concept utilizes energy from radioisotopic decay in a manner different from any existing radioisotopic power sources—as a thermal capacitor. By accumulating the heat from radioisotopic decay for long periods, the power of the source can be dramatically increased for short periods. The platform will be able to "hop" from one location to the next every 5-7 days with a separation of 5-10 km per hop. Preliminary designs show a platform that weighs around 52 kgs unfueled which is the condition at deployment. Consequently, several platforms may be deployed on a single …
Date:
February 1, 2011
Creator:
Howe, Steven D.; O'Brien, Robert C.; Taitano, William; Crawford, Doug; Jerred, Nathan; Cooley, Spencer et al.
Object Type:
Article
System:
The UNT Digital Library
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
The Mars Hopper: Development, Simulation and Experimental Validation of a Radioisotope Exploration Probe for the Martian Surface
An advanced exploration probe has been proposed by the Center for Space Nuclear Research (CSNR) to acquire detailed data from the Martian surface and subsurface, ‘hop’ large distances to multiple sites in short periods of time and perform this task repeatedly. Although several similar flying vehicles have been proposed utilizing various power sources and complex designs, e.g. solar-electric and chemical-based, the CSNR’s Mars Hopper is based on a radioisotope thermal rocket (RTR) concept. The Mars Hopper’s design relies on the high specific energies [J/kg] of radioisotopes and enhances their low specific power [W/kg] through the use of a thermal capacitance material to store thermal energy over time. During operation, the RTR transfers the stored thermal energy to a flowing gas, which is then expanded through a converging-diverging nozzle, producing thrust. Between flights, the platform will have ample time to perform in-depth science at each location while the propellant tanks and thermal capacitor recharge. Recharging the propellant tanks is accomplished by sublimation freezing of the ambient CO2 atmosphere with a cryocooler, followed by heating and pressurization to yield a liquid storage state. The proposed Mars Hopper will undergo a ballistic flight, consuming the propellant in both ascent and descent, and by …
Date:
September 1, 2012
Creator:
Jerred, Nathan D.; Cooley, Spencer; O'Brien, Robert C.; Howe, Steven D. & O'Brien, James E.
Object Type:
Article
System:
The UNT Digital Library
[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
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
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
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
Mars base buildup scenarios
Two surface base build-up scenarios are presented in order to help visualize the mission and to serve as a basis for trade studies. In the first scenario, direct manned landings on the Martian surface occur early in the missions and scientific investigation is the main driver and rationale. In the second scenario, early development of an infrastructure to exploite the volatile resources of the Martian moons for economic purposes is emphasized. Scientific exploration of the surface is delayed at first, but once begun develops rapidly aided by the presence of a permanently manned orbital station.
Date:
January 1, 1985
Creator:
Blacic, J.D.
Object Type:
Article
System:
The UNT Digital Library
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
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
[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
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
THE MARS HOPPER: AN IMPULSE DRIVEN, LONG RANGE, LONG-LIVED MOBILE PLATFORM UTILIZING IN-SITU MARTIAN RESOURCES
The requirements for performance by planetary exploration missions are increasing. Landing at a single location to take data is no longer sufficient. Due to the increasing cost, the missions that provide mobile platforms that can acquire data at displaced locations are becoming more attractive. Landers have also had limited range due to power limitations, limited lifetime of subsystems and the inability to negotiate rough terrain. The Center for Space Nuclear Research has designed an instrumented platform that can acquire detailed data at hundreds of locations during its lifetime - a Mars Hopper. The Mars Hopper concept utilizes energy from radioisotopic decay in a manner different from any existing radioisotopic power sources—as a thermal capacitor. By accumulating the heat from radioisotopic decay for long periods, the power of the source can be dramatically increased for short periods. Thus, a radioisotopic thermal rocket (RTR) is possible. The platform will be able to “hop” from one location to the next every 5-7 days with a separation of 5-10 km per hop. Each platform will weigh around 50 kgs unfueled which is the condition at deployment. Consequently, several platforms may be deployed on a single launch from Earth. With a lifetime estimated at 5-7 …
Date:
September 1, 2001
Creator:
O'Brien, Robert C.; McKay, Mark; Gross, Brian & Webb, JOnathan
Object Type:
Article
System:
The UNT Digital Library
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
[News Script: Mars]
Script from the WBAP-TV/NBC station in Fort Worth, Texas, relating a news story about Soviet Union space programs including one with an aircraft aimed towards Mars.
Date:
May 19, 1971, 10:00 p.m.
Creator:
WBAP-TV (Television station : Fort Worth, Tex.)
Object Type:
Script
System:
The UNT Digital Library
Water-bearing minerals on mars: source of observed mid-latitude water?
The Odyssey spacecraft documented the existence of heterogeneously distributed hydrogen at martian mid-latitudes, suggesting that large areas of the near-equatorial highlands contain near-surface deposits of 'chemically and/or physically bound H20 and/or OH' in amounts up to 3 .8% equivalent H20. Shallow occurrences of water ice are not stable near the martian equator, making the hydrogen deposits at these latitudes somewhat enigmatic. Clay minerals and zeolites have both been proposed as possible water-bearing constituents on Mars, and both are common terrestrial alteration products of hydrovolcanic basaltic ashes and palagonitic material comparable to those that may be widespread on Mars. Smectites within martian meteorites, attributed to hydrous alteration on Mars rather than on Earth, provide direct evidence of clay minerals from Mars. In addition, new thermal emission spectrometer (TES) data provide good evidence for unspecified zeolites in martian surface dust [6] . The nature of the hydrogen-containing material observed in the equatorial martian regolith is of particular importance to the question of whether hydrous minerals have formed in the past on Mars. Also, whether these minerals exist in a hydrated (i .e., containing H2O molecules in their structures) or dehydrated state is a crucial question . The existence of hydrous minerals is …
Date:
January 1, 2003
Creator:
Bish, D. L. (David L.); Carey, J. W. (James W.) & Fialips, C. I. (Clair I.)
Object Type:
Article
System:
The UNT Digital Library
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
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
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
Radiological Contingency Planning for the Mars Science Laboratory Launch
The U.S. Department of Energy (DOE) provides technical support to the requesting federal agency such as the Federal Bureau of Investigation, Department of Defense, the National Space and Aeronautics and Space Administration (NASA), or a state agency to address the radiological consequences of an event. These activities include measures to alleviate damage, loss, hardship, or suffering caused by the incident; protect public health and safety; restore essential government services; and provide emergency assistance to those affected. Scheduled to launch in the fall of 2009, Mars Science Laboratory is part of NASA's Mars Exploration Program, a long-term effort of robotic exploration of the red planet. Mars Science Laboratory is a rover that will assess whether Mars ever was, or is still today, an environment able to support microbial life. In other words, its mission is to determine the planet's "habitability." The Mars Science Laboratory rover will carry a radioisotope power system that generates electricity from the heat of plutonium's radioactive decay. This power source gives the mission an operating lifespan on Mars' surface of a full Martian year (687 Earth days) or more, while also providing significantly greater mobility and operational flexibility, enhanced science payload capability, and exploration of a much …
Date:
March 1, 2008
Creator:
Guss, Paul
Object Type:
Article
System:
The UNT Digital Library
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