A group of U.S. lawmakers looking to get NASA funding shifted from Earth science to human spaceflight programs didn’t let facts get in the way when making their case to the leadership of the House Appropriations Committee, which recently introduced legislation to fund the federal government for the remainder of 2011.

In a Feb. 7 letter to Reps. Harold Rogers (R-Ky.), chairman of the committee, and Frank Wolf (R-Va.), who chairs the appropriations subcommittee with NASA oversight, the group said Earth science — which they termed “global warming/climate change” research — falls outside NASA’s core mission. This is in spite of the fact that expanding human knowledge of the Earth and atmosphere is spelled out as a primary NASA objective in the National Aeronautics and Space Act, the law that serves as the space agency’s charter.

The group further asserted that climate change research activities received the “lion share” of the $1 billion allocated to NASA under the American Recovery and Reinvestment Act. This too is false: $325 million of the economic stimulus funding was earmarked for Earth science; $400 million was directed toward human spaceflight; and the remainder went to miscellaneous activities. This is readily available information.

Human spaceflight has long been and still remains by far the biggest consumer of funds at NASA. Among the international space station, the space shuttle and development of a space shuttle replacement and other human spaceflight systems, NASA spent nearly $10 billion of its $18.7 billion budget in 2010. Even after the space shuttle retires this year, human spaceflight will continue to dominate NASA’s budget: U.S. President Barack Obama’s $18.7 billion NASA funding request for 2012 includes more than $8 billion for human exploration activities, and that’s not even counting the $1 billion being sought for enabling technology development.

Meanwhile, the administration’s request for Earth science activities in 2012 is just under $1.8 billion. This would be a nearly $360 million increase over the 2010 appropriated level, which currently applies to 2011 under the continuing resolution that is funding U.S. federal activities through March 4.

Not surprisingly, the six lawmakers who signed the letter — Reps. Pete Olson (R-Texas), Bill Posey (R-Fla.), Jason Chaffetz (R-Utah), Sandy Adams (R-Fla.), Rob Bishop (R-Utah) and Mo Brooks (R-Ala.) — all come from states that host major human spaceflight-related facilities. Equally unsurprising, all are members of a political party well-stocked with global warming skeptics and which has sought to cut NASA Earth science funding in the past.

In a press release issued Feb. 14 in response to the president’s 2012 budget request, Rep. Olson went further than the letter in seeking to marginalize climate research at NASA, claiming it is not an agency mission, period. He also said the president’s budget request shortchanges human spaceflight to pay for Earth science programs and in doing so “ignores the human space flight priorities outlined by Congress last year.”

Rep. Olson is undoubtedly referring to the 2010 NASA Authorization Act signed into law in October — the one that recommended spending $1.94 billion on Earth science programs in 2012, or some $140 million more than the White House is requesting. That bill also recommends that NASA spend $5.2 billion on exploration development activities in 2012 but assumes a total agency budget of $19.4 billion, some $750 million more than has been requested. As all interested parties know by now, in the current fiscal and political environment NASA can no longer count on the annual budget growth that had been anticipated as recently as last year. Indeed, NASA would see a significant decrease in 2011 compared with 2010 in the unlikely event that the measure proposed by the House Appropriations Committee to fund the federal government for the remainder of the year is adopted in its current form.

But if Rep. Olson and his like-minded colleagues offer a less-than-accurate portrayal of NASA’s mission and how its funding is allocated, they have clearly identified a fault line as Congress debates the president’s budget requests the next two years at least. With NASA facing flat funding for the next five years — with no adjustment for inflation — and possibly even budget declines, its Earth science account is in for increasing fire from Republicans, who took control of the House this year. A similar scenario unfolded after the 1994 elections, when the GOP assumed control of both the House and Senate.

Experts have long agreed that a healthy NASA, one that returns the most value for taxpayer dollars spent, is one with a balanced portfolio that includes space and Earth science, and technology development as well as human spaceflight. Reasonable people certainly can disagree on where that balance should be struck, and of course political priorities and parochial interests will always be factors in the debate. Distortions of fact should not be.