NASA will have to live with a stagnant budget—again. The $18.7 billion proposed  by the Administration is the same amount as 2010 and 2011, and science funding would continue to hover at about $5 billion. But in the details are significant winners and losers. Earth science would grow from $1.439 billion to $1.797 billion in 2012, though House of Representatives Republicans are sure to attack a program focused on understanding global change. Meanwhile, Mars exploration—which this year stands at $438 million—would spike at $602 million next year, but plummet to less than half that amount by 2016. Funds for near-Earth object observations would quadruple to $20.4 million. And NASA Chief Financial Officer Elizabeth Robinson said the agency will kill a dark-energy mission in the hope that it can collaborate more cheaply with the European Space Agency. She added that details on how the agency will fund a massive cost overrun in the James Webb Space Telescope won't be ready until this summer.
NASA Administrator Charles Bolden acknowledged that "tough choices had to be made," adding that these are "really difficult fiscal times."
The priority in such times, he said, was safe and efficient transportation of crew and equipment into low earth orbit. The budget for human exploration was kept at $2.81 billion to fund development of a Multi-Purpose Crew Vehicle to carry humans and a Heavy Lift Launch Vehicle to launch it. An enhanced reliance on commercial industry to provide these vehicles for human spaceflight, Bolden said, was "the frugal thing for us to do and the prudent thing for us to do. … We can't do everything."
Pressed on human landings on Mars and asteroids, Bolden said it was too early to give definitive dates. Perhaps Mars in the 2030s and asteroids by 2025, but "if we can do things better, some of those dates may accelerate. We're going to have to make small steps."
See our complete coverage  of Budget 2012.