NASA begins the new year with an unexpected budget bump from Congress, which added $530 million to President Barack Obama’s request before adjourning for the holidays. The space agency's $18 billion budget for the year that began Oct. 1 is part of the $1.1 trillion spending plan Obama signed last week.

More than half the bonus is earmarked for the new heavy-lift Space Launch System rocket, which is expected to debut in 2018. NASA will now spend $1.7 billion on the program through the fiscal year ending Sept. 30, 2015, an increase of $320 million above the White House’s request.

The other prime beneficiary is NASA’s planetary science program, which ends the year with $1.44 billion in its budget, an increase of $157 million. Congress set aside $100 million to begin work on a mission to Jupiter’s ocean-bearing moon Europa. The Obama administration had requested $15 million.

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“This mission does not officially exist, though the president’s budget did request $15 million this year to study low-cost concepts (a step in the right direction),” Casey Dreier, advocacy director with California-based Planetary Society, wrote in a column.

“$100 million is a considerable increase,” Dreier wrote. “NASA would be crazy not to use this funding to start a real mission, but that decision likely lies with the Office of Management and Budget, which approves their funding requests. Let’s hope they get the message in time to request a new start in 2016.”

Meanwhile, scientists have been searching for signs that the ice-covered moon has plumes of water shooting out into space from its south pole. The discovery was reported last year by a team using the Hubble Space Telescope. So far, however, analysis of Europa images taken by the Saturn-orbiting Cassini spacecraft have not shown plumes, scientists reported at the American Geophysical Union conference earlier this month.

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“It is certainly still possible that plume activity occurs, but that it is infrequent or the plumes are smaller than we see at Enceladus,” Cassini scientist Amanda Hendrix, with the Planetary Science Institute in Pasadena, said in a press release.

“If eruptive activity was occurring at the time of Cassini’s flyby, it was at a level too low to be detectable,” she said.