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Returning an Entire Near-Earth Asteroid in Support of Human Exploration Beyond Low-Earth Orbit

Brophy, John R. and Friedman, Louis (2012) Returning an Entire Near-Earth Asteroid in Support of Human Exploration Beyond Low-Earth Orbit. In: Global Space Exploration Conference, 22-24 May 2012, Washington, DC.

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This paper describes the results of a study into the feasibility of identifying, robotically capturing, and returning an entire Near-Earth Asteroid (NEA) to the vicinity of the Earth by the middle of the next decade. The feasibility of such an asteroid retrieval mission hinges on finding an overlap between the smallest NEAs that could be reasonably discovered and characterized and the largest NEAs that could be captured and transported in a reasonable flight time. This overlap appears to be centered on NEAs roughly 7 m in diameter corresponding to masses in the range of 250,000 kg to 1,000,000 kg. The study concluded that it would be possible to return a ~500,000-kg NEA to high lunar orbit by around 2025. The feasibility is enabled by three key developments: the ability to discover and characterize an adequate number of sufficiently small nearEarth asteroids for capture and return; the ability to implement sufficiently powerful solar electric propulsion systems to enable transportation of the captured NEA; and the proposed human presence in cislunar space in the 2020s enabling exploration and exploitation of the returned NEA. Placing a 500-t asteroid in high lunar orbit would provide a unique, meaningful, and affordable destination for astronaut crews in the next decade. This disruptive capability would have a positive impact on a wide range of the nation’s human space exploration interests. It would provide a high-value target in cislunar space that would require a human presence to take full advantage of this new resource. It would offer an affordable path to providing operational experience with astronauts working around and with a NEA that could feed forward to much longer duration human missions to larger NEAs in deep space. It represents a new synergy between robotic and human missions in which robotic spacecraft would retrieve significant quantities of valuable resources for exploitation by astronaut crews to enable human exploration farther out into the solar system. The capture, transportation, examination, and dissection of an entire NEA would provide valuable information for planetary defense activities that may someday have to deflect a much larger near-Earth object. Transportation of the NEA to lunar orbit with a total flight time of 6 to 10 years would be enabled by a ~40-kW solar electric propulsion system with a specific impulse of 3,000 s. The flight system could be launched to low-Earth orbit (LEO) on a single Atlas V-class launch vehicle, and return to lunar orbit a NEA with at least 28 times the mass launched to LEO. Longer flight times, higher power SEP systems, or a target asteroid in a particularly favorable orbit could increase the mass amplification factor from 28-to-1 to 70-to-1 or greater. The NASA GRC COMPASS team estimated the full life-cycle cost of an asteroid capture and return mission at ~$2.6B.

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Additional Information:“Copyright 2012 by Jet Propulsion Laboratory - California Institute of Technology. Published by the IAF, with permission and released to the IAF to publish in all forms.” The research described in this paper was sponsored by the Keck Institute for Space Studies (KISS) and was carried out in part at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. The people and organizations listed on page 2 of this report participated in the KISS-sponsored study. It is their work that is summarized in this paper and the KISS study co-leads gratefully acknowledge their contributions. In addition, the Collaborative Modeling for Parametric Assessment of Space Systems (COMPASS) team at NASA GRC performed a study of the Asteroid Retrieval Mission concept resulting in a conceptual flight system configuration and mass estimate. Their work is also gratefully acknowledged by the study co-leads. GLEX-2012.11.1.7x12334
Group:Keck Institute for Space Studies
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Keck Institute for Space Studies (KISS)UNSPECIFIED
Record Number:CaltechAUTHORS:20160223-163335708
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:64703
Deposited By: Colette Connor
Deposited On:24 Feb 2016 18:31
Last Modified:03 Oct 2019 09:40

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