UPDATED at 12:25pm

WASHINGTON — U.S. President Barack Obama on Dec. 22 signed into law a short-term appropriations bill that will keep the federal government, including NASA, funded at 2010 spending levels through March 4, according to a White House news release.

The temporary spending measure, H.R. 3082, was adopted 193-165 by the U.S. House of Representatives late Dec. 21.

Known as a continuing resolution, or CR, H.R. 3082 does not weigh-in on NASA, which means the agency would operate in the coming months at spending rates proportional to the $18.72 billion appropriated for all of 2010. In addition, NASA would be prohibited from initiating new programs and would be required to continue funding the Moon-bound Constellation program Obama sought to abandon in the $19 billion budget blueprint for 2011 that was sent lawmakers in February.

In its enacted form, H.R. 3082 represents a dramatic departure from an earlier version drafted in the House and adopted there Dec. 8 that would have funded the federal government for the remainder of fiscal year 2011. That measure would have increased NASA spending by $186 million over 2010 levels and provided authority to cancel Constellation contracts and initiate new programs in the current fiscal year. U.S. Sen. Daniel Inouye (D-Hawaii), chairman of the Senate Appropriations Committee, included similar language for NASA in draft omnibus legislation for 2011, but that measure stalled in the Senate under Republican opposition to earmarks contained in the $1.1 trillion funding package.

Marion Blakey, president of the Aerospace Industries Association, a trade group here, said NASA and other federal agencies face challenges under a continuing resolution.

“Operations vital to our national security and economic prosperity could suffer without full appropriations for these agencies,” she said in a Dec. 16 statement urging passage of the omnibus measure.

But congressional sources say the short-term CR, if extended for the full year, would provide all but $276 million of the funding NASA sought for 2011, and that the bill’s lack of specificity could afford the agency discretion when it comes to spending the money.

For example, while the new law does not specify that a specific pot of money be used to fund an additional space shuttle flight to the international space station as called for in the NASA Authorization Act of 2010, the $3.1 billion appropriated for the space shuttle program in 2010 is more than enough to pay for the mission, plus the two manifested shuttle missions NASA plans to fly in 2011.

NASA spokesman Michael Cabbage said the agency is reviewing H.R. 3082, but that the measure would not hinder any plans to fly the additional shuttle mission as called for in the NASA Authorization Act of 2010 that Obama signed into law Oct. 11.

“The continuing resolution by itself does not endanger the extra shuttle mission, because on an annualized basis the continuing resolution provides enough funding to fly the mission,” he said in a Dec. 20 e-mail.

While H.R. 3082 provides no relief from a prohibition in last year’s appropriation that bars NASA from canceling Constellation contracts, its lack of specificity for NASA programs gives the agency authority to continue developing a multipurpose crew vehicle for deep space missions as called for in the authorization act. And because Congress provided $100 million for development of a heavy-lift rocket in the 2010 appropriation, NASA under the CR could begin work on that or a similar vehicle as directed in the authorization measure.

H.R. 3082 could pose potential problems for NASA’s Commercial Orbital Transportation Services (COTS) program, a five-year-old effort to nurture development of commercial rockets and cargo vessels capable of resupplying the space station. Obama requested $312 million for the effort in 2011, a sum that greatly exceeds the $39.1 million appropriated in 2010. However, while H.R. 3082 requires agencies to honor 2010 spending ceilings for individual accounts, it does not require those agencies to fund individual programs at specific levels, giving NASA some wiggle room in applying the $3.7 billion it will have to spend on exploration in 2011 to cover the COTS shortfall.

However, the agency could face other obstacles in moving out on commercial crew initiatives this year. Under Obama’s 2011 budget proposal, NASA would have received $500 million to foster privately built rockets and spacecraft capable of ferrying astronauts to and from low Earth orbit. But because the program is new, and was not funded in the 2010 appropriation, NASA could be left to await new appropriations legislation before it can get started.