A House committee on Thursday approved an amendment to a bill that would clear NASA to launch an additional shuttle flight next summer to deliver critical supplies and equipment to the International Space Station.
The move came as the House Committee on Science and Technology was reviewing its version of NASA's $19 billion 2011 funding package. The Senate version of the appropriations legislation already included the additional flight. But major differences remain in other key areas, including how much money goes to support development of a new private-sector manned launch industry, the timetable for development of a NASA heavy-lift rocket for deep space exploration, and plans for a new government-designed manned spacecraft.
Even so, Science and Technology Committee Chairman Bart Gordon (D-Tenn.) said in a statement that the House legislation "sets a clear, sustainable, and executable path for NASA, especially in the area of human space flight."
The Obama administration earlier this year proposed canceling NASA's Constellation moon program, including the Ares I and Ares V rockets the agency had planned to build to replace the shuttle. The Orion crew capsule that would have been launched atop the Ares I rocket would be converted into a space station crew lifeboat.
At the same time, the president called for a transition to private-sector rockets and capsules to ferry astronauts to and from the space station, allowing NASA to focus on development of new heavy-lift rockets and capsules for eventual flights to nearby asteroids and, eventually, to Mars.
But the president's plan would defer work on a heavy lifter until 2015, delaying deep space missions beyond low-Earth orbit until the middle of the 2020s in favor of near-term development of advanced technologies.
Supporters of the administration's space policy applauded the shift to private-sector launch services, arguing that increased efficiencies and innovation would open up the high frontier to more extensive--and routine--use. Under the administration's proposed budget, NASA would spend $6 billion over the next five years to spur development of private-sector launch services.
But critics decried the proposed write-off of some $9 billion already spent on the Constellation program, the long development cycle proposed for eventual deep space missions, and the reliance on as-yet-unproven commercial launchers and capsules.
The House and Senate versions of NASA's appropriations package both cut out the moon as NASA's next major goal and both extend space station operations through 2020 as requested by the president. But both reduce funding for commercial manned space initiatives. The Senate version provides $1.3 billion over the next three years while the president's initial proposal called for $3.3 billion. The House version would provide just $450 million over the next three years.
The Senate version also would accelerate development of a heavy lift rocket, using components of the Constellation program where possible, for initial flights as early as 2016. The House version would stretch out development to around 2020. Both versions also call for development of a government-sponsored crew capsule, based on the Orion design, for deep space exploration and possible space station support.
"I have the sense that the rest of the policy community thinks the Senate bill is a reasonable compromise we can live with," said a space policy analyst who asked not to be named.
In 2004, the Bush administration directed NASA to finish the space station and retire the shuttle fleet by the end of fiscal 2010. An additional $600 million later was promised to pay for shuttle operations through the end of calendar 2010 and shuttle program managers came up with additional savings to cover costs through early 2011.
NASA currently has just two flights on its shuttle manifest. First up is a mission by the shuttle Discovery, scheduled for launch November 1, to deliver spare parts and equipment to the station in a logistics module that will be permanently attached to the lab complex.
In keeping with NASA's post-Columbia safety policies, the shuttle Endeavour will be available for possible rescue duty if any major problems develop that might prevent a safe re-entry for Discovery's crew.
Assuming a rescue flight isn't needed, Endeavour will be launched February 26 to deliver the $1.5 billion Alpha Magnetic Spectrometer physics experiment to the space station along with additional supplies and spare parts.
The shuttle Atlantis is being processed to serve as the rescue vehicle for Endeavour's crew. NASA managers have been lobbying for months to win approval to actually launch Atlantis on a final flight next June to deliver one last load of equipment.
By launching Atlantis with a reduced crew of four, a second shuttle would not be required for rescue duty. If a problem prevented a safe re-entry, the yet-to-be-named Atlantis astronauts could seek safe haven aboard the space station and rotate home aboard Russian Soyuz capsules.
It would not be easy and it would take months to cycle all four crew members back to Earth aboard already planned Soyuz flights. But supporters believe the benefits of a final resupply mission outweigh the risks and justify the $1.6 billion needed to extend the shuttle program through mid-2011.
"This mission will help minimize the spaceflight gap by stretching out the human spaceflight capabilities into mid 2011," Rep. Suzanne Kosmas, a Florida Democrat, said Thursday, introducing an amendment for "contingent authorization." "This additional launch provides the most risk-free logistical support in the next year...I urge you to support my amendment and to authorize this critical shuttle mission in order to preserve our workforce and maximize the investments we've made in the International Space Station."
The amendment, which passed on a voice vote, would pay for the flight by transferring funds from NASA's space station and exploration budgets.
"I think the White House is on board with it," the policy analyst said.