Asteroid Redirect Mission

The Asteroid Redirect Mission (ARM), also known as the Asteroid Retrieval and Utilization (ARU) mission and the Asteroid Initiative, is a potential future space mission proposed by NASA. Still in the early stages of planning and development, the Asteroid Retrieval Robotic Mission (ARRM) spacecraft would rendezvous with a large near-Earth asteroid and use robotic arms with anchoring grippers to retrieve a 4-meter boulder from the asteroid.

The spacecraft will characterize the asteroid and demonstrate at least one planetary defense technique before transporting the boulder to a stable lunar orbit, where it could be further analyzed both by robotic probes and by a future manned mission, ARCM (Asteroid Redirect Crewed Mission). If funded, the mission would be launched in December 2021, with the additional objectives to test a number of new capabilities needed for future human expeditions to deep space, including advanced ion thrusters.

The main objective of the Asteroid Redirect Mission is to develop deep space exploration capabilities needed in preparation for a human mission to Mars and other Solar System destinations per NASA's Journey to Mars flexible pathways.

Space tug missions, to disaggregate non-time-critical Mars logistics from crew, can reduce the costs by as much as 60% (if using advanced solar electric propulsion (ion engines)) and reduces overall mission risk by enabling on-site check-out of critical systems before the crew departs

Not only will the solar electric propulsion (SEP) technologies and designs be applied to future missions, but the ARRM spacecraft will be left in a stable orbit for reuse. The project has baselined any of multiple refueling capabilities; the asteroid-specific payload is at one end of the bus, for possible removal and replacement via future servicing, or as a separable spacecraft, leaving a qualified space tug in cislunar space.

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