It all comes down to Curiosity.
The big nuclear-powered Mars rover is NASA's last chance to drive scientific instruments around on the Martian surface in this decade. After that, it may be 2020 before the U.S. can afford to launch another rover to the red planet.
As recently as last fall, NASA had plans for launching a mission to bring back Mars samples to analyze on Earth as early as 2022. Now the expert team set up to develop new options for a downsized Mars program is working on the assumption that there will be surface samples delivered to orbit around Mars no later than 2033.
At that remove, it is difficult to predict whether they will be returned to Earth by an unpiloted vehicle or by human explorers, says Orlando Figueroa, a retired NASA “Mars czar” brought back from retirement to pick up the pieces left by President Barack Obama's fiscal 2013 NASA budget request.
Obama's space advisers have made their priorities clear. A May 7 “statement of administration policy” includes a threat to recommend that Obama veto the Republican-drafted House appropriations bill that includes NASA funding. The White House bureaucracy rejected proposed increases for Mars exploration and complained about a $330 million cut in seed money for the commercial vehicles NASA hopes will be able to deliver astronauts to the International Space Station later in the decade.
“This would increase the time the United States will be required to rely solely on foreign providers to transport American astronauts to and from the space station,” the Office of Management and Budget stated in policy language inserted by Deputy NASA Administrator Lori Garver. “While the administration appreciates the overall funding level provided to NASA, the bill provides some NASA programs with unnecessary increases at the expense of other important initiatives.”
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