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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 109 records · Page 6

Hybrid NEP-Chemical Vehicle and Propulsion Technology Study for Crewed Mars Missions

Nuclear Electric Propulsion (NEP) is a suite of technologies with the potential to enable crewed opposition-class missions to Mars. Each subsystem comprising an NEP system has multiple technology options that present tradeoffs in vehicle sizing and technology development risk. Multiple vehicle concepts have been studied in the past and are currently being studied at NASA. Three models have been developed to illustrate the impact of key technology parameters on overall sizing for a crewed Mars transportation vehicle. Vehicle mass required to close the mission as a function of NEP system alpha (kWe/kg) and specific impulse (Isp) is estimated with a detailed trajectory model. A power system mass model estimates alpha as a function of power and radiator mass assumption. A power conversion system thermodynamic model predicts the radiator area required to close a Brayton cycle power conversion system. Combined with the architecture mass required for mission closure, the radiator area and alpha model provide insight into how technology development may impact the mission. Our focus is on parametric sweeps of the whole design space rather than any particular point design. Results from the mission model comparing electric propulsion technology (Hall, Ion, Magnetoplasmadynamic) and both 2039 and 2042 opposition-class mission launch windows are included. The results of the study illustrate the technology parameters that can result in mission closure and illustrate where the architecture is sensitive to variations in technology performance or requirements.

Matthew Duchek↗

Aspects of parking orbit selection in a manned Mars mission

For any round-trip Mars mission, the selection of a parking orbit at Mars must consider the precession caused by the oblateness of the planet. This precession will affect the departure condition for Earth return and, therefore, the initial mass required in low Earth orbit (LEO). In this investigation, which considers precession effects, minimum initial LEO masses were obtained for parking orbits characterized by having near-equatorial inclinations, high eccentricities, and three-dimensional departure burns (i.e., a burn with an in-plane and an out-of-plane velocity increment component). However, because near-equatorial inclination orbits have poor planetary coverage characteristics, they are not desirable from a science viewpoint. To enhance the potential for satisfying science requirements along with landing site accessibility, a penalty in the initial LEO mass is required. This study shows that there are a set of orbits characterized by low to moderate essentricities (e = 0.2 to 0.5) and nonequatorial inclinations (i = 70 to 140 deg) that reduce this initial LEO mass penalty. Therefore, careful selection of a parking orbit at Mars can enhance the potential for satisfying science requirements with minimal mass penalties.

Desai, Prasun N.↗

The Human Mars Mission: Transportation Assessment

If funding is available, and for NASA planning purposes, the Human Mars Mission (HMM) is baselined to take place during the 2011 and 2013/2014 Mars opportunities. Two cargo flights will leave for Mars during the first opportunity, one to Mars orbit and the second to the surface, in preparation for the crew during the following opportunity. Each trans-Mars injection (TMI) stack will consist of a cargo/payload portion (currently coming in at between 65 and 78 mt) and a nuclear thermal propulsion (NTP) stage (currently coming in at between 69 and 77 mt loaded with propellant) for performing the departure ΔVs to get on to the appropriate Mars trajectories. Three 66,700 N thrust NTP engines comprise the TMI stage for each stack and perform a ΔV ranging from 3580 to 3890 m/s as required by the trajectory (with gravity losses and various performance margins added to this for the total TMI ΔV performed). This paper will discuss the current application of this NTP stage to a Human Mars mission, and project what implications a nuclear trans-Earth injection (TEI) stage as well as a bi-modal NTP stage could mean to a human visit to Mars.

Mars missions↗

Exobiology and Future Mars Missions

Scientific questions associated with exobiology on Mars were considered and how these questions should be addressed on future Mars missions was determined. The mission that provided a focus for discussions was the Mars Rover/Sample Return Mission.

Mckay, Christopher P.↗

Impact of lunar oxygen production on direct manned Mars missions

A manned Mars program made up of six missions is evaluated to determine the impact of using lunar liquid oxygen (LOX) as a propellant. Two departure and return nodes, low Earth orbit and low lunar orbit, are considered, as well as two return vehicle configurations, a full 70,000-kg vehicle and a 6800-kg capsule. The cost of lunar LOX delivered to orbit is expressed as a ratio of Earth launch cost.

Young, Roy M., Jr.↗

Optimal parking orbits for manned Mars missions

This paper summarizes a Mars parking orbit optimization effort. This parking orbit study includes the selection of optimal elliptic Mars parking orbits that meet mission constraints and that include pertinent apsidal misalignment losses. Mars missions examined are for the opportunity years of 2014, 2016, and 2018. For these mission opportunities, it is shown that the optimal parking orbits depend on the year that the mission occurs and are coupled with the outbound, Mars stay, and return phases of the mission. Constraints included in the parking orbit optimization process are periapsis lighting angle (related to a daylight landing requirement), periapsis latitude (related to a landing latitude range requirement) and the vehicle Trans-Earth-Injection stage mass. Also, effects of mission abort requirements on optimal parking orbits are investigated. Off-periapsis maneuvers for Mars orbit capture were found to be cost effective in reducing the mission delta-V for the 2016 abort from Mars capture scenario. The total capture and departure delta-V was `split' between the capture maneuver and the departure maneuver to reduce the 2016 Mars departure delta-V to below the level of the corresponding stage of the 2014 baseline mission. Landing results are provided that show Mars landing site access from the optimal elliptic parking orbits for Mars excursion vehicles with low (0.2) and high (1.3 and 1.6) lift to drag ratio.

Cupples, Michael L.↗

Manned Mars mission psychological issues

The research on isolated environments over the last thirty years suggests that psychological factors associated with such environments will lead to negative changes in individual and group performance. A mission to Mars will be the greatest undertaking ever devised by the human species. The members of such a mission will be in an environment whose potential dangers are not even completely known at this time. The psychological factors generated by such an environment, and which might adversely affect accomplishment of mission goals, can be minimized or planned for in advance. It is hoped that these issues will not be ignored in planning for this great adventure.

Santy, Patricia A.↗

Surface Nuclear Power for Human Mars Missions

The Design Reference Mission for NASA's human mission to Mars indicates the desire for in-situ propellant production and bio-regenerative life systems to ease Earth launch requirements. These operations, combined with crew habitation and science, result in surface power requirements approaching 160 kilowatts. The power system, delivered on an early cargo mission, must be deployed and operational prior to crew departure from Earth. The most mass efficient means of satisfying these requirements is through the use of nuclear power. Studies have been performed to identify a potential system concept using a mobile cart to transport the power system away from the Mars lander and provide adequate separation between the reactor and crew. The studies included an assessment of reactor and power conversion technology options, selection of system and component redundancy, determination of optimum separation distance, and system performance sensitivity to some key operating parameters. The resulting system satisfies the key mission requirements including autonomous deployment, high reliability, and cost effectiveness at a overall system mass of 12 tonnes and a stowed volume of about 63 cu m.

Mason, Lee S.↗

Applications of nuclear propulsion to Mars missions

The basic features of a piloted mission to Mars is described, and it is shown how nuclear propulsion can improve upon the various performance measures of such a mission. An overview of the history and types of nuclear propulsion in the U.S. is presented. Current planning to develop nuclear propulsion technology for the Space Exploration Initiative is addressed.

Rosen, Robert↗

Human Mars Mission Performance Crew Taxi Profile

Using the results from Integrated Mission Program (IMP), a simulation language and code used to model present and future Earth Moon, or Mars missions, this report presents six different case studies of a manned Mars mission. The mission profiles, timelines, propellant requirements, feasibility and perturbation analysis is presented for two aborted, two delayed rendezvous, and two normal rendezvous cases for a future Mars mission.

Duaro, Vince A.↗

Manned Mars mission crew factors

Crew factors include a wide range of concerns relating to the human system and its role in a Mars mission. There are two important areas which will play a large part in determining the crew for a Mars mission. The first relates to the goals and priorities determined for such a vast endeavor. The second is the design of the vehicle for the journey. The human system cannot be separated from the other systems in that vehicle. In fact it will be the human system which drives the development of many of the technical breakthroughs necessary to make a Mars mission successful. As much as possible, the engineering systems must adapt to the needs of the human system and its individual components.

Santy, Patricia A.↗

Surface activities on the first piloted Mars mission

The objectives of the first piloted Mars mission, in addition to safe Mars landing and return to earth for the crew, would encompass a demonstration of human working capabilities in the Martian environment, the exploration of the landing site, and the establishment of that planet's potential for the support of permanent human habitation. An evaluation is presently made of constraints on Martian service activities, mission risk considerations, and the three mission profiles that can be envisioned for total durations of 14, 21, and 35 months.

Duke, Michael B.↗

Astronomy on a manned Mars mission

Three extra-solar-system astronomical experiments onboard a manned Mars mission are proposed. First, a modest, 50 cm aperture optical-ultraviolet-infrared telescope (or pair used as an interferometer) coupled with the Mars-Sun baseline would increase the number (by a factor of 3.4) and a volume of stars with accurately measured distances via stellar parallax and, therefore, greatly improve upon the cosmic distance scale; the darker sky at Mars would also provide nearly a full astronomical magnitude deeper images of distant and low brightness objects (limited by zodiacal light). Second, a gamma-ray burst detector coupled with similar detectors in other parts of the solar system will be used to reduce the position error boxes and to study the nature of these energetic sources. Third, the long baselines on a Mars mission radio interferometer will provide a view of the radio universe at unprescedented resolution, 4 x 10 to the minus 9th arcsec at 1 mm wavelength, which can potentially resolve the engine in nearby active galaxies. Each of these experiments is relatively inexpensive, taking advantage of the human presence for operation and maintenance, and the long Earth to Mars baseline.

Burns, Jack O.↗

The Challenges of Developing a Food System for a Mars Mission

A viewgraph describing the food system that NASA is developing for Manned Mars Missions is shown. The topics include: 1) The President's Vision for U.S. Space Exploration -January 14, 2004; 2) Introducing Orion (and Ares); 3) Mercury (1961-1963); 4) Gemini (1965-1966); 5) Apollo (1968-1972); 6) Skylab (1973-1974); 7) Shuttle/Mir (1995-1998); 8) Shuttle (1981-present) International Space Station (2000-present); 9) NASA Stored Food System; 10) Advanced Food Technology; 11) Orion Missions; 12) Orion Challenges; 13) Food Packaging; 14) Mars Mission Assumptions; 15) Planetary Food System Selected Crops; 16) Food Processing Equipment Constraints; 17) Crew Involvement Constraints; 18) Advanced Food Technology Integration; 19) Research Highlights Internal; and 20) Research Highlights External.

Perchonok, Michele↗

Natural radiation hazards on the manned Mars mission

The hazards of the natural radiation environment (cosmic rays and solar energetic particles) on a manned mission to Mars are considered. These hazards are addressed in three different settings: the flight to Mars where the astronauts are shielded only by the spacecraft; on the surface of Mars under an atmosphere of about 10 g/sq cm carbon dioxide; and under the surface of Mars where additional shielding would result.

Letaw, John R.↗

Aerobrakes For A Manned Mars Mission

Paper presents results of study of aerobraking in manned mission to Mars. Describes geometry and aerodynamic characteristics of aerobraked vehicle. Discusses computer program, WTRAJ, used to simulate trajectories near planets. Analyzes aerocapture processes for both Mars and Earth. Examines mass efficiency, or saving in propellant mass, afforded by aerobraking.

Menees, G. P.↗

A Long Range Science Rover For Future Mars Missions

This paper describes the design and implementation currently underway at the Jet Propulsion Laboratory of a long range science rover for future missions to Mars. The small rover prototype, called Rocky 7, is capable of long traverse. autonomous navigation. and science instrument control, carries three science instruments, and can be commanded from any computer platform and any location using the World Wide Web. In this paper we describe the mobility system, the sampling system, the sensor suite, navigation and control, onboard science instruments. and the ground command and control system.

Hayati, Samad↗