NASA’s proposed asteroid-capture mission may be worthwhile, but only if the agency can place it clearly on a path that leads to human boots on the surface of Mars, members of the House Science Committee said May 21.

Opening a hearing on the advantages of capturing a small asteroid and positioning it in cislunar space over a mission to the lunar surface, panel leaders from both parties expressed skepticism at the new mission plan.

“As our space program prepares for the next step to Mars, Congress must ensure that there is a strategic plan in place,” said Rep. Lamar Smith (R-Texas), noting that Congress has repeatedly endorsed using the lunar surface as a “training ground” for human missions to Mars. “Another option presented by NASA this year is an asteroid-retrieval mission. It is difficult to determine what advantages this may offer without a plan to evaluate.”

NASA has kept its latest design reference missions (DRMs) a secret, on the grounds they are “internal, pre-decisional studies that help inform our decision-making process,” according to David Weaver, the agency’s chief spokesman.

But Administrator Charles Bolden has spoken more often recently of Mars as the target of human exploration for today’s generation.

“I’m delighted to hear the NASA administrator speak about Mars as the ultimate destination, at least in the next 20 years, for human exploration,” said Rep. Donna Edwards of Maryland, ranking Democrat on the House Science space subcommittee. “ … The administration’s recent proposal to capture a near-Earth asteroid, bring it into trans-lunar orbit, and potentially to send humans there is yet another possible step [to Mars]. But before we look at interim steps, we need first to understand what it takes to get to Mars.”

Rep. Steve Palazzo (R-Miss.), chairman of the space subcommittee, worried that the asteroid-capture might be a “detour,” and said he was “not convinced it is the right way to go.” But it was Smith who summed up his panel’s skepticism over the new plan.

“Without a consensus for the original plan, NASA haphazardly created a new asteroid-retrieval mission,” Smith said.

“Unfortunately, NASA did not seek the advice of its own Small Bodies Assessment Group before presenting the mission to Congress. If NASA had sought the advisory group’s advice, they would have heard it was ‘entertaining, but not a serious proposal.’ Maybe that’s why they didn’t ask.”

Despite the skepticism, Louis Friedman, the former Planetary Society chief who co-chaired the Keck Institute panel that originally drafted the asteroid-capture proposal, told the committee that the mission would be scientifically useful in itself, and also would help engineers learn what it would take to divert an asteroid on a collision course with Earth.

He noted that private companies are beginning to look for ways to exploit the mineral resources in near-Earth asteroids, and said the mission could also bring other spacefaring nations into a new cooperative venture with NASA.

“This project will not just unify NASA with science, technology, robotic and human components,” he said. “It will unify many others globally with a great adventure. Europe, Japan, Russia, all have asteroid mission plans, and solar electric spacecraft in operation. They could join in the mission development.”