— Three Republican senators, including presidential candidate John McCain (R-Ariz.), have asked U.S. President George W. Bush to prevent NASA from taking any steps over the next year that would preclude flying the space shuttle beyond 2010.

In an Aug. 25 letter to Bush, McCain and Sens. Kay Bailey Hutchison (R-Texas) and David Vitter (R-La.) wrote that continuing to fly the space shuttle beyond its scheduled retirement might be the
United States
‘ only viable near-term option for accessing and utilizing the international space station (ISS) in light of uncertain relations with
. A copy of the letter was posted on McCain’s senate Web site.

NASA plans to book passage for its astronauts aboard Russian Soyuz vehicles until the Orion Crew Exploration Vehicle – currently targeted for a 2015 debut – or a U.S. commercial alternative is ready to make regular trips to the station.
is under contract to provide such Soyuz services through 2011 when a temporary exemption from a nonproliferation law barring NASA from making space station-related payments to
is due to expire.

The White House asked Congress in April to amend the Iran-North Korea-Syria Nonproliferation Act (INKSNA) to permit NASA to continue to buy Soyuz vehicles as long as the space station remains in orbit. In June, Senate Foreign Relations Committee Chairman Joseph Biden (D-Del.) – since chosen as Democratic presidential candidate BarackObama’s running mate – introduced the International Space Station Payments Act of 2008 (S. 3103) as a courtesy to the White House. The Foreign Relations Committee, however, took no action on the bill before the August recess.

Sen. Bill Nelson (D-Fla.), a key member on such issues, told several Florida newspapers in late August that Russia’s military action against Georgia had all but killed any chance of the legislation passing this year, either as a stand-alone bill or as part of some other measure. Nelson, in addition to chairing the Senate Commerce space and aeronautics subcommittee, also sits on the Foreign Relations Committee.

In their letter to Bush, McCain, Hutchison and Vitter said Russia’s actions “raised new questions about the wisdom” of providing a permanent exemption from an INKSNA provision barring NASA from buying space station-related goods and services from Russia while it helps Iran acquire missiles. But the three make no predictions about the legislation’s chances this year.

“Any consideration of granting this waiver would reflect concern for the continued viability of the ISS, and the need to have a means for
astronauts and scientific researchers to be able to make the full use of this multi-billion dollar facility,” the three senators wrote.

Less than a year after the 2003 Space Shuttle Columbia accident brought a halt to space station construction, Bush called for completing the space station and retiring the shuttle in 2010 before fielding Orion and setting course for a 2020 return to the Moon. His plan was consistent with the recommendations of the Columbia Accident Investigation Board, which warned against operating the aging shuttle fleet past 2010 without undertaking a lengthy and thorough recertification process.

McCain, Hutchison and Vitter make no mention of the safety concerns that factored into the decision to retire the shuttle, emphasizing instead the financial considerations that were in play at the time.

“The decision to terminate the Shuttle upon completion of the ISS, planned for 2010, was primarily a means of enabling the development of new vehicles without a large upsurge in NASA’s overall budget,” McCain, Hutchison and Vitter wrote. “That decision certainly made sense from a fiscal point of view, and making use of the Russian Soyuz vehicles as an expansion of the original partnership between the
and our other International partners was also seen to be of value. Our concern is that we do not have a guarantee that such cooperative and mutually beneficial activity will continue to be available, and the successful utilization of the ISS may thus be jeopardized.”

Hutchison, whose state is home to NASA’s
, sponsored 2005 legislation designating the space station a national laboratory. Vitter’s home state of
includes the Michoud Assembly Facility, a contractor-operated NASA facility in
New Orleans
that produces space shuttle external tanks.

The senators say they continue to support speeding up development of Orion and its Ares 1 launcher – Johnson and Michoud have key roles in those efforts, too – as well as NASA’s efforts to stimulate commercial alternatives. But they argue neither of those efforts offers a “clear near-term solution.”

“Given all of these considerations, we believe it imperative, as NASA continues the transition from the Space Shuttle to the successor vehicles, that the means for producing additional flight hardware and obtaining additional flight engineering and support services, not be completely and irretrievable lost through destruction or deterioration, at least until a clear path to alternative launch capabilities is at hand,” McCain, Hutchison and Vitter wrote. “At minimum, we request that you direct NASA to take no action for at least one year from now that would preclude the extended use of the Space Shuttle beyond

Similar provisions, the three wrote, were included in a NASA authorization bill (S. 3270) that was approved by the Senate Commerce Committee this summer but has since stalled.

Sen. Richard Shelby of Alabama, the ranking Republican of the Senate Appropriations commerce, justice, science subcommittee, told the Huntsville Times he would support extending the shuttle program only if there was enough additional funding provided to keep Orion and Ares – key programs for his state’s NASA Marshall Space Flight Center – on track. “If the Bush administration intends to propose additional shuttle flights, then we must have a corresponding increase in the NASA budget request,”
said. “Otherwise, I would oppose any such effort that will undercut our research and development of
‘s next generation of spaceflight.”

Wayne Hale, a self-described “shuttle hugger” who stepped down as the space shuttle program manager earlier this year to take a NASA headquarters job, says it is already too late to start talking about keeping the shuttle flying.

“Hey, I am the biggest shuttle hugger there is. I think it is the best spacecraft ever built. But I also deal in the real world,” Hale wrote Aug. 28 on his official NASA weblog. “Where does the money come from? Where do the people – who should be working on the moon rocket – where do they come from? We started shutting down the shuttle four years ago. That horse has left the barn.”

And although Hale does not mention it in his blog post, keeping the shuttle flying would not eliminate NASA’s Soyuz dependence. In addition to transporting astronauts to the station, a Soyuz remains docked there for six-months at a time to bring the crews home in an emergency. The shuttle is designed for roughly two-week stays in orbit.

McCain’s letter followed the Aug. 16 release of an Obama space policy white paper stating the Democrat’s support behind flying at least one shuttle mission beyond the 10 remaining on NASA’s manifest. Obama space advisers, including Nelson, have said Obama supports securing an additional $2 billion for NASA in short order to help it minimize the gap between the last flight of shuttle and the first flight of Orion. Obama’s white paper does not mention the extra $2 billion, but does pledge the Democratic candidate’s support for “expedit[ing] the development of the Shuttle’s successor systems for carrying Americans to space so we can minimize the gap.” It also says Obama would seek funding for the additional shuttle flight to keep it from interfering with the development of Orion and Ares.