Reaction has been less than enthusiastic to NASA's plan to catch a small asteroid, nudge it into orbit around the Moon, and send astronauts to visit it.
The Asteroid Redirect Mission (ARM) is the U.S. space agency's near-term goal, with a do-by date of 2025. Few planetary scientists think the return will justify the investment, and Congress is uninspired at best. it will probably never happen.
But the mission plan also can be seen as kind of a Trojan horse -- a sneaky way for the U.S. space industry to focus its intellectual resources on solving the problems that must be solved to land humans on Mars.
This video that NASA prepared to plug the asteroid mission shows how applicable it would be to sending human space travelers on to the Red Planet.
The animation focuses on what astronauts would do to study an asteroid in the targeted distant retrograde orbit around the Moon -- find it, rendezvous with it and spacewalk to it -- all in an area of space never visited by humans before. They would use a heavy-lift Space Launch System (SLS) and an Orion capsule to get there.
NASA is building the SLS and Orion to take humans to Mars, and so far Congress supports that work. The asteroid side of the ARM -- before the human hook-up - would require high-power solar electric propulsion and advanced robotics to capture a small asteroid or a boulder off a big one and nudge it toward the Moon. Both would be essential for a human mission to Mars, as would the sensors necessary for rendezvous and proximity operations in lunar orbit.
Even if none of this ever happens, the ARM concept has focused some of the best minds in the country on how to do it. That mental energy won't be wasted. The ideas it generates can be applied to a human Mars expedition, and they will -- someday.