WASHINGTON — NASA received its full $18.7 billion proposal for 2010 in the omnibus spending bill U.S. President Barack Obama signed into law Dec. 16, but Congress by no means rubber-stamped the agency’s request.

Congress differed with NASA’s proposed spending priorities by directing unsought funds toward a handful of scientific research missions. The bulk of the funding shift moves roughly $95 million within the agency’s Science Mission Directorate, sending almost half of it to Earth science programs, a $1.4 billion funding line Obama wants to steadily increase to $1.6 billion by 2015.

In addition, the bill reprioritizes money within NASA’s aeronautics research and space operations accounts to pay for a handful of new projects, and includes language that would prevent the Obama administration from scaling back or canceling NASA’s space shuttle replacement efforts in the absence of formal legislative approval from congressional appropriators.

Frustrated by a lack of visibility into NASA spending, lawmakers combined almost $450 million from the agency’s science, exploration and space operations programs, as well as the so-called Cross-Agency Support account that funds agency-wide management, infrastructure and technology efforts, into a new, separate construction and environmental compliance account.

Moving these funds into a single pot of money resulted in slightly lower top-line spending levels for some mission directorates, though lawmakers provided a sizeable boost to education programs while holding science funding close to the administration’s $4.47 billion request.

Despite shifting some $95 million between various science, cross-agency support, and construction and environmental compliance accounts, spending on some science projects actually increased in the 2010 bill, including a $45 million boost for Earth science, a $31 million plus-up for heliophysics and a $13 million increase for planetary science.

With NASA expected to propose in its forthcoming 2011 budget request a replacement for the Orbiting Carbon Observatory (OCO) spacecraft destroyed during a Feb. 24 launch mishap, the bill directs $25 million to get the ball rolling in 2010. In addition, language in a manager’s statement accompanying the bill requires the Science Mission Directorate to apply at least $25 million in unspent 2009 funds for OCO.

Other Earth science programs saw funding boosts as well, including $15 million for the next two decadal survey missions, the Climate Absolute Radiance and Refractivity Observatory and the Deformation, Ecosystem Structure, and Dynamics of the Ice missions. Another $5 million was designated for the Deep Space Climate Observatory, an Earth-observing satellite originally proposed in 1998 by then-U.S. Vice President Al Gore to provide a continuous view of the entire Earth. Competing priorities placed the satellite in storage until late 2008 when NASA began recertifying the craft for possible launch atop an expendable rocket.

NASA’s heliophysics request grew from $605 million to $636 million, a funding boost that contributed to a $36 million plus-up for the Solar Probe Plus mission. NASA requested only $4 million in 2010 for Solar Probe Plus, a heat-resistant spacecraft designed to plunge deep into the sun’s atmosphere to sample solar wind and magnetism firsthand. Although NASA’s 2010 budget request indicates a planned launch date of August 2018, program officials say that prior to the fiscal year that began Oct. 1, the agency’s budget request envisioned a 2008 call for instrument proposals and a 2015 target launch date. The instrument solicitation was not released until Dec. 3, more than a year later than planned.

Concerned with the agency’s move to slow-roll Solar Probe Plus, lawmakers included an additional $36 million to keep it on track for a 2015 launch.

Funding boosts for other science projects add $13 million to NASA’s $1.36 billion planetary science budget, including an $11.2 million plus-up to a $3.7 million request for the International Lunar Network, a multinational effort to develop a geophysical sensor net on the Moon’s surface. Another $2 million was shifted to increase the agency’s $3.8 million request for near-Earth object observation, supporting research at the Arecibo Observatory in Puerto Rico.

Astrophysics programs suffered a $1.1 million reduction from the agency’s $1.12 billion request, though lawmakers fully funded the next-generation James Webb Space Telescope at $441.4 million in 2010. Report language accompanying the bill is critical of the telescope’s ongoing cost overruns and the need for lawmakers to approve periodic funding adjustments to the program, to include $95 million in the last six months alone.

NASA’s Space Operations Mission Directorate’s $6.17 billion request was trimmed slightly to $6.14 billion, due in part to shifting some $51 million to construction and environmental compliance and cross-agency support accounts. However, lawmakers added $50 million to NASA’s $2.267 billion request for international space station operations to study the potential for next-generation manned rockets and spacecraft to service existing and future space observatories.

 Meanwhile, lawmakers provided no additional funds for the agency’s Aeronautics Research Mission Directorate, which requested $507 million for 2010. Instead, $6 million was moved to cross-agency support while several aeronautics accounts were trimmed at the margins to collectively fund a $15 million increase in aviation safety. Lawmakers directed those funds be used to establish a university-affiliated research center to collaborate with NASA on unmanned aircraft systems and remote sensing research applications.

Anticipating the potential for NASA to realign its human spaceflight activities and investments beginning in 2011, lawmakers included language in the omnibus bill to prevent any significant changes to the agency’s Constellation program, a 5-year-old effort to replace the aging space shuttle with new rockets and spacecraft optimized for Moon missions.

Last year, a White House-appointed panel led by former Lockheed Martin chief Norm Augustine found Constellation incompatible with the agency’s projected budget. The Obama administration has spent months weighing scenarios outlined in the Augustine panel’s Oct. 22 final report, and is expected to announce a decision in the coming weeks that likely will reshape the future of NASA’s manned spaceflight plans.

Although the bill shields Constellation from significant cuts or outright termination, it also shaves $39 million from NASA’s $3.505 billion request for the program in 2010. It also requires the agency to devote $100 million of those funds to advance work on existing or new heavy-lift launch capabilities, though NASA had requested only $25 million for its Ares 5 heavy-lift rocket.

Another funding reduction to exploration was $20.7 million from the agency’s $287 million request for a high-tech incubator program that could enable future human and robotic exploration while reducing mission risk and cost.