WASHINGTON — The White House wants to extend the international space station’s (ISS) mission by four years to 2024, and NASA is willing to keep the $3-billion-a-year orbital outpost flying even if every international partner but Russia deserts the project, a senior NASA official said Jan. 8.

“We’re prepared to do what we have to do if the partners choose to take a different path,” William Gerstenmaier, who as associate administrator for NASA’s Human Exploration and Operations Mission Directorate is the agency’s top human spaceflight official, said on a Jan. 8 conference call with reporters.

NASA managers have been advocating for a decision on space station extension as part of the White House’s 2015 budget request, which is expected to be delivered to Congress not sooner than February. The station is already cleared to operate through 2020, so congressional appropriators — who draw up budgets one year in advance — will not have to make any hard decisions about funding trade-offs until after U.S. President Barack Obama leaves office in January 2017.

“On budget, through the budget horizon out through 2020 there’s no additional funds required for this activity, so it’s not a [matter of]  someone has to pass additional funds,” Gerstenmaier said. “We had reserved funds to deorbit station in the outyears. Those funds, instead of being applied for deborbit, will be applied for the extension of life. We’ve acquired enough spares through the near-term horizon that there’s not a budget up required for additional spares. So there’s not a unique budget hurdle that we have to go through beyond the next standard, normal budget process.”

The mission extension got immediate buy-in from one important congressional stakeholder.

“I applaud the decision to extend the operations of the International Space Station,” U.S. Senate Appropriations Committee chairwoman Barbara Mikulski (D-Md.) said in a Jan. 8  statement. “Keeping ISS flying — and continuing the important research that goes on there — means taxpayers get more bang for the buck from this unique laboratory.”

Although NASA is prepared to fly with help from only Russia — which built and operates the space station’s core module and has more experience with long-duration crewed spaceflight than any national space agency — Gerstenmaier said NASA has “talked to our partners about this [and] they want to go forward with this, it’s just working through the government approval … to get where they need to be.”

The European Space Agency (ESA) in November 2012 committed to participating in the space station through 2020. This decision was widely viewed as a compromise between Germany, a strong advocate of ESA’s role, and France, which has been less enthusiastic. Jean-Yves Le Gall, president  of the French space agency, CNES, said ESA members will have to come to a consensus regarding space station participation beyond 2020. Speaking with reporters  here  Jan. 8, Le Gall noted the financial difficulties of some of ESA’s member states, saying the issue today is coming up with the funds to support the existing commitment. Only after challenge has been tackled can the members make a decision on participation beyond 2020, he said. Le Gall said Germany’s position on funding beyond 2020 is unclear at this point. “France will find a consensus with its European partners,” he said.

The White House’s approval of a four-year mission extension — which is four years fewer than what NASA and space station prime contractor Boeing Space Exploration of Houston have been pushing — was first reported by the Orlando Sentinel late Jan. 7.

NASA made the White House’s policy decision official just a day before the heads of international space agencies were scheduled to meet here for the International Academy of Astronautics’ Heads of Space Agencies Summit. Many of these officials represent countries which, like the United States, face declining national budgets and are considering reduced spending on civil space activities.

Meanwhile, NASA is already looking out for ways to trim the space station’s $3 billion annual operating budget, about half of which is dedicated to transporting cargo and crew to the outpost, Gerstenmaier said. Complicating that effort is the need to decide, by this spring, whether to pay Russia to take U.S. astronauts to the space station beyond 2016. NASA’s current contract with the Russian space agency, Roscosmos, covers astronaut transportation to and from the space station through 2016, and emergency crew rescue services through June 2017. At the same time, NASA is paying three U.S. companies to develop crew transportation systems the agency could use for this purpose as soon as late 2017.

The going rate for a single astronaut to fly Soyuz round trip is roughly $70 million and must be booked three years in advance.

At the end of the Jan. 8 call, Gerstenmaier appealed to members of the media to focus on the station’s ability to serve as a springboard to more distant points in the solar system, rather than the cost of operating the outpost.

“If we as a species are going to get off the Earth … we’re going to have to use this small foothold called the international space station to go do that,” Gerstenmaier said. “This is our only opportunity to really move forward.”

SpaceNews Editor Warren Ferster contributed to this story from Washington. 

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Dan Leone is a SpaceNews staff writer, covering NASA, NOAA and a growing number of entrepreneurial space companies. He earned a bachelor’s degree in public communications from the American University in Washington.

Warren Ferster is the Editor-in-Chief of SpaceNews and is responsible for all the news and editorial coverage in the weekly newspaper, the spacenews.com Web site and variety of specialty publications such as show dailies. He manages a staff of seven reporters...