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Future human exploration missions to Mars are being studied by NASA and industry.
Several approaches to the Mars mission are being examined that use various
types of propulsion for the different phases of the mission. The choice and
implementation of certain propulsion systems can significantly impact mission
performance in terms of trip time, spac...
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... requirements for the various type "B" trajectories are presented in Table 1 and 2. The data illustrates that only "B3" and select "B2" type trajectories come close to the delta-v's that can be packed on MTVs utilizing chemical and NTP propulsion using multiples SLS launches 1,2 . However these suffer from trip times near, or exceeding, the nominal mission time ~1000 days. ...Similar publications
National Aeronautics and Space Administration (NASA) Deep Space Network (DSN) currently administers the navigation system for all of NASA’s Martian spacecraft landers. For its travel to Mars, the spacecraft is located and guided via 2-way radio communication and navigation system. Although beyond par navigation potential is guaranteed by DSN, such...
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... Several abort scenarios were considered in case of an emergency on E2 where the crew would need to return to Earth midway to Ceres. Past studies for Mars abort scenarios using high-thrust NTP have considered three options for an abort, such as a direct return, a free return, and powered fly-by [14]. In the case of a human mission to Ceres, a direct return would not be feasible since the calculations returned much higher ΔV values than for Mars missions, given the high-energy heliocentric orbit. ...
... An NTP provides the most robust approach for future Mars, and possibly round-trip lunar missions. [1][2][3][4][5] NASA and industry studies since the 1960's have indicated that nuclear thermal propulsion and fission power is a promising technology that has an established foundation that can be matured to flight status within the next ten years and that can be used for fast trip transfers for human missions to Mars or fast 24-48 hour taxis to the Moon. Many detailed mission and system studies have been performed that have shown the benefits in terms of payload, transfer time, and increased mission science via more power or reduced spacecraft mass. ...
Aerojet Rocketdyne is working with NASA, the Department of Energy, and other industry to define a more affordable path to nuclear propulsion and power use for lunar, Mars and broader solar system exploration missions.
Aerojet Rocketdyne's (AR) recent work builds on the legacy design, analysis, and testing knowledge gained from the Rover/NERVA (Nuclear Engine for Rocket Vehicle Applications) to create a feasible Low Enriched Uranium (LEU) design that has been shown to provide high thrust capability (e.g., 25,000 lbf) for faster trajectories and a higher specific impulse (Isp) (e.g., 850 to 900 seconds) than can be achieved with chemical propulsion (e.g., 460 seconds) systems. Some evolutionary approaches with carbide fuel may be able to provide over 1,000 seconds of specific impulse. Evolving and modernizing Nuclear Thermal Propulsion (NTP) engine designs to use LEU reactor fuel has proven to be feasible, and affordable approaches to manufacturing and testing are being pursued using an organized technology maturity plan (TMP) with NASA oversight. LEU NTP engine and reactor development activity is proceeding in 2019 and architecture analysis is showing NTP will provide enabling benefits for multiple solar system missions. Making LEU NTP practical for use in Lunar and Mars missions is foremost and is the expected first use of the engine system. Later missions can evolve using the NASA Space Launch System (SLS) and LEU NTP stages to send orbiters to the gas giants and to the interstellar medium.
This paper discusses and provides background on the analysis and results from the work that is proceeding on developing a LEU NTP system. It is expected that this propulsion system can be used for lunar tugs, crewed and cargo missions to Mars and as a rapid transfer space transport stage.
... An NTP provides the most robust approach for future Mars and possibly round-trip lunar missions. 1,2,3,4,5 NASA and industry studies since the 1960's have indicated that nuclear thermal propulsion and fission power is a promising technology that has an established foundation that can be matured to flight status within the next ten years and that can be used for fast trip transfers for human missions to Mars or fast 24-48 hour taxis to the Moon. Many detailed mission and system studies have been performed that have shown the benefits in terms of payload, transfer time, and increased mission science via more power or reduced spacecraft mass. ...
Studies of Nuclear Thermal Propulsion (NTP) over the past several decades, and updated most recently with the examination of Low Enriched Uranium (LEU), have shown nuclear propulsion is an enabling technology to reach beyond this planet and establish permanent human outposts at Mars or rapidly travel to any other solar system body. The propulsion needed to propel human spacecraft needs high thrust to operate withinthe deep gravity well of a planet and provide high propulsive efficiency for rapid travel and reduced total spacecraft mass.
NTP can provide the thrust to move a spacecraft between orbits, can operate as a dual-mode system that provides power and propulsion capability, provides a strong architectural benefit to human and robotic exploration missions, and provides a path toward reusable in-space transportation systems. NTP provides smaller vehicle systems due to its specific impulse (ISP) being twice that of the best cryogenic liquid rocket propulsion and can thus provide reduced trip times for round-trip missions from Earth to Mars.
Aerojet Rocketdyne (AR) is working with NASA, other government agencies, and other industry partners to improve the design and reduce the cost of NTP engine systems. Current NTP designs focus on thrust sizes between 15,000-lbf (~67-kN) and 25,000-lbf (~111-kN). AR in 2019 has examined various reactor cores and enhancements to optimize LEU NTP designs. The enhancements improve the mission architecture robustness and provide more design margin for Mars vehicles across many mission opportunities, trip times, and mission types.
The LEU NTP design can offer mission architecture stages or elements that can be used for both Lunar and deep space exploration missions. The NTP designs enable packaging of various NTP stage designs (e.g., crew Mars vehicle stage elements, cargo stage derivatives, a deep space stage with payload, Lunar stage elements) on the NASA SLS Block 2 using the 8.4-meter fairing. The primary LEU core designs studied, for the above-mentioned missions, have relied on liquid hydrogen for the propellant and coolant and use Zirconium Hydride within a structural element as the neutron moderator. Several designs have been examined that use Beryllium Oxide with the fuel elements in the core to eliminate the structural elements.
The LEU NTP engine systems studied have typically been used only for the primary delta-V burns (e.g., earth escape, planetary capture, planetary escape, earth return capture). LEU NTP engine systems have also been examined using a the LEU reactor fuel element and moderator element approach to perform orbital maneuvering system (OMS) burns during the mission simply by permitting the reactor to keep operating at very low power levels during the entire mission.
This paper will discuss the various engine system and mission design trades performed in 2019 for Mars and lunar missions when using a single NTP or a cluster of NTP engines.
