In May 2013 The Planetary Society issued a statement saying that the Society "conditionally supports NASA's plan to capture a small asteroid and place it in lunar orbit." The Society’s support was conditional because the detailed goals, costs, and implementation plan for this asteroid mission were not yet well defined. In the past year, NASA has made commendable progress in developing its plans for what now is known as the Asteroid Redirect Mission (ARM). Based on this progress, we now offer strong, but still conditional, support for ARM.
Our concern is that a rigorous and independent cost and technical evaluation of the mission has not yet been completed. We worry that the ARM effort will prove a great deal more expensive than is currently being suggested. As has happened too often in the past, cost overruns lead to budgeting difficulties for years into the future. NASA's numerous other worthy science and exploration endeavors become difficult to manage and complete. We thus urge NASA as soon as possible to undertake as comprehensive a cost and technical evaluation as is feasible at this early stage in mission definition.
The Planetary Society in 2008 developed a "Beyond the Moon" roadmap that called for a step-by-step expansion of human activity into deep space. One of the steps on the path to Mars recommended in that Roadmap was a rendezvous with an asteroid in its native orbit. However, the initial versions of the Space Launch System and Orion spacecraft mandated by the Congress and being developed by NASA cannot send astronauts on a weeks-long journey to such an asteroid without the expensive addition of a habitation module. Thus it makes sense to define an activity that can be carried out sooner, traveling to a location that can be reached with systems currently under development. The ARM is such an activity; in redirecting an asteroid to a location where it can be reached using the first generation Space Launch System and Orion spacecraft, it certainly reflects the spirit of our 2008 Roadmap.
NASA has set the ARM effort in the broader context of developing and demonstrating technologies relevant to human missions to Mars and its moons, such as the large solar electric propulsion system that would be used to transport cargo to the Martian vicinity. The ARM mission would help gain experience with deep-space technologies and operations relevant to missions to Mars, including long-duration life support, navigation, rendezvous, docking, and extra-vehicular activity. With the Asteroid Redirect Mission, NASA would gain experience relevant both to developing an infrastructure for possible missions to the lunar surface and to missions deeper into space, ultimately to Mars and its moons.
The Planetary Society sees the ARM initiative as one—but only one—step in achieving the goal of its 2008 Roadmap, humans traveling to Mars. We hope for a series of increasingly ambitious deep space missions during the 2020s, establishing an exploratory cadence that will carry explorers away from our home planet. For all the above reasons, we support ARM, with the condition that it soon undergo a full cost and technical evaluation, as an initial step in a new era of U.S.-led discovery and space achievement.