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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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This paper focuses only on the design, implementation, and application of the POC testbed.
Recent developments in miniaturization of spacecraft systems and science instruments have led to great interest in their application to deep space missions. A recent JPL study, for example, considered the design of a small spacecraft which could yield useful science data from fast flybys of the near-earth asteroids. Called AIM (Asteroid Investigation with Microspacecraft), three spacecrafts would be launched with Pegasus into low earth orbit (LEO), separated, and then remain there up to 2 weeks, each waiting for the opportune time to inject to a flyby with a preselected asteroid. Each spacecraft has its own kick stage for this injection maneuver. This paper briefly describes the spacecraft design and capability, the asteroid flyby opportunities available within the coming decade, and other possible mission scenarios which could take advantage of a single launch multi-spacecraft option.
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Quasi-optimal trajectory analysis computer program for optimal spacecraft guidance by iterative techniques
Trajectory synthesis for variable point mass, constant thrust, fixed staging time vehicles in vacuum
Solar arrays applicability in conjunction with fuel cells and batteries considered for supplying power for lunar roving vehicles
Multimission solar electric spacecraft of modest size and variable propellant loading for interchangeable space missions - Vol. 1A
Multimission solar electric spacecraft for interchangeable space missions final technical systems data - Vol. 1B
Multimission solar electric spacecraft for interchangeable space missions program plans and cost estimates - Vol. 2
Multimission solar electric spacecraft for interchangeable interplanetary missions - Final summary technical report
The performance of nuclear electric propulsion (NEP) systems has been evaluated for a wide variety of missions in an attempt to establish the commonality of NEP system requirements. Emphasis was given to those requirements and system characteristics which serve as guidelines for current technology development programs. Various interactions and tradeoffs between NEP system and mission parameters are described. The results show that the most significant factors in selecting NEP system size are launch mode (direct or spiral escape) and to a lesser extent, launch vehicle capability. Other factors such as mission and payload have little influence, thus allowing one NEP system to be used for many missions. The results indicated that a 100 kWe NEP would be suitable for most direct escape missions and a 250 kWe NEP system would be suitable for more demanding missions that use the spiral escape mode.
The unmanned planetary exploration to be conducted in the last two decades of this century includes many higher energy missions which tax all presently available propulsion systems beyond their limit. One candidate with the versatility and performance to meet these mission objectives is nuclear electric propulsion (NEP). Additionally, the NEP System is feasible in orbit raising operations with the Shuttle or Shuttle/Tug combination. A representative planetary mission is described (Uranus-Neptune flyby with probe), and geocentric performance and tradeoffs are discussed. The NEP System is described in more detail with particular emphasis on the power subsystem consisting of the thermionic reactor, heat rejection subsystem, and neutron shield.
Results of a mission engineering analysis of nuclear-thermionic electric propulsion spacecraft for unmanned interplanetary and geocentric missions. Critical technologies assessed are associated with the development of nuclear electric propulsion (NEP), and the impact of its availability on future space programs. Specific areas of investigation include outer planet and comet rendezvous mission analysis, NEP stage design for geocentric and interplanetary missions, and technology requirements for NEP stage development. A multimission NEP stage can be developed to perform both multiple geocentric and interplanetary missions for a 1983 launch. Identified pacing NEP technology requirements are the development of 20,000 full power hour ion thrustors and thermionic reactor and the development of related power conditioning. The resulting NEP stage design provides both inherent reliability and high payload mass capability.
For abstract, see N76-14196.
For abstract, see N76-14196.
The cost savings that could be obtained by the use of SIM to perform certain sensor electrical interfacing functions that were historically an integral part of the sensor are evaluated. Reduction in both the nonrecurring and recurring costs of this sensor interface hardware could be achieved through the use of SIM, and the study concludes that the development and use of certain power conditioning and data handling SIM units are economically justified.
The functional and performance requirements for support of multimission radio science are established. The classes of radio science investigation are described and the needed data is discussed. This document is for a sliding ten year period and will be iterated as the mission set evolves.