NEWS BRIEF: President Barack Obama's budget request for the upcoming fiscal year would provide NASA $17.7 billion total, a 0.3 percent decrease from the 2012 enacted level. It is the first budget request since NASA's space shuttle program became decommissioned after completing its final mission last July, which has left the agency without a domestic option to transport crew to the International Space Station and therefore solely dependent upon the Russian Soyuz for the service.

In order to close that U.S. capability gap, the budget would continue to help private companies develop transportation systems. In the long run, NASA hopes to purchase their services for access to the space station.

Development of a government-owned heavy-lift rocket and crew capsule for human deep space exploration would continue to be supported in the budget. An un-crewed test flight is expected as early as 2017.

The budget would officially re-baseline the James Webb Space Telescope, which has had back-to-back schedule and cost overruns. It is now targeted for a 2018 launching.

The budget would reduce robotic exploration of Mars, including terminating the 2016 and 2018 ExoMars missions that were previously planned with the European Space Agency. Critics question what impact this would have toward progress of human missions to the planet.

Activities to restart production of plutonium-238, an essential source of electrical power for long-term missions, would continue to be supported in the budget. Existing amounts of the radioisotope available to NASA are expected to be exhausted within the next decade.

The budget proposal was submitted to Congress on Monday.

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