| CAPE CANAVERAL, Fla., March 24
CAPE CANAVERAL, Fla., March 24 Two spacewalking
astronauts ventured outside the International Space Station on
Friday on the first of three outings to prepare the orbiting
research laboratory for future commercial space taxis and to
tackle maintenance chores, NASA TV showed.
U.S. station commander Shane Kimbrough, 49, and French
flight engineer Thomas Pesquet, 39, floated outside the
station's airlock at about 7:30 a.m. EDT (1130 GMT).
Working 250 miles (402 km) above Earth, the astronauts
expected the spacewalk to last 6.5 hours as they work to
reconfigure the $100 billion station, operated by 15 nations,
and add docking ports for new spaceships in development by
Boeing and Space Exploration Technologies, or SpaceX.
Kimbrough, making his fifth spacewalk, headed to the
station's central beam to upgrade a computer relay box before
turning his attention to a docking system that will be used by
future fleets of commercial space taxis.
The U.S. National Aeronautics and Space Administration is
making the retrofits in the hope that private companies could
begin flying astronauts to the station by the end of 2018. This
would break Russia's monopoly on crew transportation, a service
that costs NASA more than $80 million per person.
The first of the space taxis is scheduled for an unmanned
debut test flight later this year.
During Friday's spacewalk, Kimbrough will disconnect four
cables on a docking tunnel to be used by the new commercial
space taxis. On Sunday, ground control teams will then use the
station's robot arm to move it onto a different module.
A second spacewalk by Pesquet and NASA astronaut Peggy
Whitson is planned for Thursday, to reconnect cables to the
relocated docking tunnel.
Once all the work is finished, the U.S. side of the station
will have two docking ports for passenger spaceships and two for
cargo ships. Russia, which jointly operates the station with
NASA, has five docking ports.
Also during Friday's spacewalk, Pesquet inspected hoses,
attachments and other components of the station's ammonia
cooling system. Flight controllers have noticed a small leak in
the system and want to find the source.
A third spacewalk is on hold pending the arrival of a cargo
ship that includes items to be installed during the outing.
Engineers are troubleshooting a problem with the cargo
ship's launch vehicle, an Atlas 5 rocket made by the Lockheed
Martin-Boeing partnership United Launch Alliance. Launch had
been targeted for Monday.
(Editing by Letitia Stein and Bernadette Baum)