NASA astronauts on Tuesday successfully wrapped up a Christmas Eve spacewalk to make repairs at the orbiting International Space Station, the US space agency said."Repressurization began at 1:23 pm CT (1923 GMT), the spacewalk concluding at seven hours, 30 minutes," a NASA commentator said.

NASA astronauts step out on Christmas Eve spacewalk

Two NASA astronauts stepped out Tuesday on a rare Christmas Eve spacewalk to complete repairs at the International Space Station.

"The 10th spacewalk of the year at the International Space Station is now officially under way," a NASA commentator said at 6:53 am (1153 GMT), marking the start of the second of two outings to replace an ammonia pump module whose internal control valve failed December 11.

Astronauts making delayed spacewalk to fix cooling system

Two astronauts were to make their second spacewalk from the International Space Station on Tuesday to try to fix a faulty cooling system, US space agency NASA said. Americans Rick Mastracchio and Michael Hopkins spent five-and-a-half hours outside the station on Saturday to detach a malfunctioning pump module.

They had been due to replace it during a spacewalk on Monday, but that was postponed until Tuesday after a fault was detected in Mastracchio's spacesuit following Saturday's walk.

If all goes well on Tuesday, a third spacewalk - which had originally been planned for Christmas Day - would not be needed, NASA said.

Saturday's spacewalk, which was completed about 30 minutes earlier than expected, was Mastracchio's seventh but the first for Hopkins.

Mastracchio has now logged 44 hours on spacewalks.

It was the first spacewalk by NASA since July when there was a problem with a space helmet worn by European Space Agency astronaut Luca Parmitano, of Italy, who was accompanied by NASA's Chris Cassidy.

The fault with the cooling system on December 11 led the six-man crew of the space station to switch off all equipment deemed non-essential, halting dozens of scientific experiments.

The station, a project involving 15 countries, orbits at more than 400 kilometres above the Earth.

Source: Voice of Russia