The House for the first time in five years will weigh in on national space policy today, considering a bipartisan endorsement of President Bush's initiative to send humans to the moon and Mars and authorizing an extra $1.3 billion over the next two years to forestall cuts in NASA's traditional programs in science and aeronautics.

The National Aeronautics and Space Administration Authorization Act of 2005 also endorses a maintenance visit by the space shuttle to the Hubble Space Telescope and calls on NASA to develop a national aeronautics policy.

But in the face of a partisan impasse, the bill does not take a position on whether to retire the space shuttle in 2010, an administration goal favored by the Republicans, or to keep it in service until a next-generation spacecraft is developed, the view favored by House Democrats and by both parties in the Senate.

The House bill, scheduled for debate and a vote today, reflects a desire by Congress to make a statement on space policy as NASA gets ready to fly the space shuttle for the first time in 21/2 years and undertakes a major shift in focus toward Bush's "Vision for Space Exploration." The last such bill was passed in 2000.

The chief concern, expressed by leaders of both parties, is that science and aeronautics programs, longtime mainstays of NASA's portfolio, not be sacrificed to realize the moon-Mars mission.

"I have said many times that we don't want NASA to be a single-mission agency," said House Science Committee Chairman Sherwood L. Boehlert (R-N.Y.). "We have not in any way, shape or manner denigrated the 'Vision,' but we are also making it clear that this is an agency capable of doing many things at once."

The bill, covering 2006 and 2007, blends a one-year GOP proposal intent on endorsing Bush's wish to return humans to the moon by 2020 with a three-year Democratic counteroffer emphasizing the research potential of the international space station. The Science Committee approved the measure 36 to 0.

The compromise used about the same NASA budget levels proposed by the White House but shifted money from "exploration" -- Bush's top priority -- to science, aeronautics and education. Then lawmakers added $509.3 million to the 2006 budget and $764.8 million for 2007, after the White House requested that exploration funding be restored.

The authorization bill, a policy statement that provides no funding, calls for NASA budgets of $17 billion for 2006 and $17.7 billion for 2007, about $1.3 billion more than the administration sought. But whether the agency will ultimately get the money remains an open question. The Senate's proposed NASA appropriation for 2006 is $200 million below Bush's request, while the House's appropriation is $15 million above the White House proposal.

The administration issued a statement late yesterday supporting the bill but expressing concerns that "must be satisfactorily addressed" about the proposed funding increases for aeronautics, maintaining the Hubble telescope and basic research aboard the space station.

The House bill and bipartisan legislation awaiting passage in the Senate reflect lawmakers' desire to join the debate on the White House's exploration initiative, which was announced in January 2004 but languished as NASA wrestled with returning the shuttle program to flight after the disintegration of the space shuttle Columbia in February 2003.

Interest piqued quickly this spring, however, with the appointment of new NASA Administrator Michael D. Griffin, an experienced engineer and space scientist who is a blunt-spoken, aggressive advocate of human space travel beyond "lower Earth orbit," where the space shuttle and space station dwell.

Lawmakers in both houses of Congress describe Griffin in glowing terms, and his popularity smoothed NASA'S legislative path: "In large part the atmosphere has changed," said Sen. Bill Nelson (Fla.), the top Democrat on the Senate Commerce subcommittee on science and space and a former astronaut. "We feel like we have an administrator who knows something about space."

Before coming to NASA, on the other hand, Griffin had made no secret of his lack of enthusiasm for the space shuttle and space station, and lawmakers wanted to make sure that the space station's research potential is realized and that the United States fulfills its obligations to its international space station partners.

Sen. Kay Bailey Hutchison (R-Tex.), chairman of the subcommittee, has included a provision in the Senate's NASA bill making the station a national laboratory, thereby opening it up to funding from other agencies and the private sector and "expanding the variety of areas to which space research can be applied."

But space-loving lawmakers appeared most interested in preventing NASA from tying its future solely to the moon-Mars initiative. "I'm concerned about cannibalizing other missions," said Rep. Bart Gordon (Tenn.), the House Science Committee's top Democrat.

"Then in four years we could vote to put the Mars money into something we need on Earth, like school buses," he added. "If you've undercut NASA's other missions, there's nothing good left in NASA, so we'll cut even more."

In January 2004, President Bush listened to a telecast by C. Michael Foale from the international space station. The bill includes support for the station.