By Irene Klotz
WASHINGTON (Reuters) - The Obama administration wants to keep the International Space Station, a $100 billion orbital research outpost that is a project of 15 nations, flying until at least 2024, four years beyond a previous target, NASA said on Wednesday.
The extension will give the U.S. space agency more time to develop the technologies needed for eventual human missions to Mars, the long-term goal of NASA's human space program.
Keeping the station in orbit beyond 2020 also opens a window for commercial companies and researchers to benefit from hefty U.S. investment in the outpost.
NASA's costs for operating the station, which flies about 250 miles above Earth, run about $3 billion a year. About half that sum is spent on transporting crew and cargo.
"Ten years from today is a pretty far-reaching, pretty strategic-looking vision," NASA Associate Administrator Bill Gerstenmaier told reporters on a conference call.
"This extension… opens up a large avenue of research onboard station. It also changes the perspective for the commercial (transportation) providers. Now they can see a market that extends to at least 2024," he said.
In addition to commercial U.S. cargo ships and planned passenger space taxis, companies and research organizations are beginning to make use of the station's unique microgravity environment to develop a range of new products and technologies, including medications and off-the-shelf, shoebox-sized satellites.
Construction of the orbital outpost began in 1998. The prime partners in the venture, with the United States, include Russia, Europe, Japan and Canada. It has been permanently staffed by rotating crews of astronauts and cosmonauts since 2000.
Extending the station "is not a U.S.-only decision," Gerstenmaier said. "We talk to our partners about this. They want to go forward with this. It's just working through the government approval," he said.
"We're prepared to do what we have to do if the partners choose to take a different path," Gerstenmaier added.
A technical review by prime station contractor Boeing shows the station's laboratories, structural frame and other hardware are safe to fly until 2028, program manager John Shannon said earlier on Wednesday at the opening of an international space exploration and policy summit.
"If the physical hardware continues to operate the way we believe it does ... that leaves the door open in the future to extend," Gerstenmaier said.
At the end of its life, the station will be steered down into the atmosphere, where it will incinerate. Re-entry will take place over an ocean so any surviving debris will not threaten populated areas.
The first of up to six U.S. supply runs to the station this year was slated for launch on Wednesday, but the flight was canceled due to extremely high levels of radiation caused by a huge solar flare.
Orbital Sciences Corp, one of two firms hired by NASA to ferry cargo to the station following the retirement of the space shuttles in 2011, may try to launch its Antares rocket and Cygnus cargo ship on Thursday. The rocket flies from a commercial spaceport on Wallops Island, Virginia.
"We are concerned about mission failure," Orbital Science's Chief Technical Officer Antonio Elias told reporters. Radiation from the solar flare could potentially interfere with the rocket's avionics and other critical systems.
Privately owned Space Exploration Technologies, or SpaceX, which also holds a NASA contract to fly cargo to the station, is preparing for its third supply run on February 22.
(Editing by Tom Brown and Dan Grebler)