Astronauts embark on second spacewalk to fix cooling system

Aug 11, 2010

NASA astronauts aboard the International Space Station Wednesday began a second spacewalk to work on repairing a failed cooling system, the space agency said.

Astronauts Doug Wheelock and Tracy Caldwell Dyson suited up and switched to independent power in the space station airlock at 1227 GMT, initiating the walk in space.

Once outside the station, they will work to unhook and remove a busted pump module that caused the cooling problem in preparation for attaching a replacement.

"If all goes as planned, the spare pump will be installed during the third spacewalk," said the US space agency, adding that that operation would be possible "no earlier than Sunday."

Wheelock and Dyson's first spacewalk on Saturday lasted eight hours and three minutes, the sixth longest ever, but they were unable to remove the defective pump.

They disconnected three of four fluid lines connected to the pump but a fourth line leaked, causing them to stop work, said.

Conditions on the ISS remained stable and the station's six-person crew -- three Americans and three Russians -- was not in danger, NASA officials said.

If the efforts this week fail -- a highly unlikely scenario, NASA has said -- the astronauts would no longer be able to cool most of the space station components.

But the crew would not be in danger because they could move to the Russian segment of the ISS, which has its own cooling system.

According to NASA figures, without thermal controls the ISS's sun-facing side would roast at 250 degrees Fahrenheit (121 Celsius), while the outpost's dark side would plunge to some minus 250 degrees Fahrenheit (minus 157 Celsius).

The ISS, which orbits 350 kilometers (220 miles) above Earth, is a sophisticated platform for scientific experiments.

It is a 100-billion-dollar cooperation between 15 countries, and has been manned uninterrupted since October 1990.

Explore further: Mysteries of space dust revealed

add to favorites email to friend print save as pdf

Related Stories

NASA delays spacewalks to fix ISS cooling pump

Aug 05, 2010

NASA on Thursday pushed back by one day the first of two spacewalks to fix a pump module on the International Space Station's (ISS) cooling system that dramatically failed last week. ...

Space station astronauts fall short on repairs

Aug 07, 2010

(AP) -- A pair of space station astronauts had to hammer loose a stuck connector Saturday during an urgent spacewalk to restore a crucial cooling system, and ran out of time before they could remove a broken ...

Next space station spacewalk no earlier than Wednesday

Aug 09, 2010

Flight controllers and engineers continue meetings to review the results from the first spacewalk conducted Saturday by International Space Station Expedition 24 Flight Engineers Doug Wheelock and Tracy Caldwell ...

3rd spacewalk needed to restore cooling system

Aug 08, 2010

(AP) -- A pair of space station astronauts had to hammer loose a stuck connector during an urgent spacewalk to restore a crucial cooling system Saturday, then an ammonia leak erupted and hampered the entire ...

Recommended for you

Caterpillar comet poses for pictures en route to Mars

10 hours ago

Now that's pure gorgeous. As Comet C/2013 A1 Siding Spring sidles towards its October 19th encounter with Mars, it's passing a trio of sumptuous deep sky objects near the south celestial pole this week. ...

Hoisting a telescope with helium

10 hours ago

Many a child has forgotten to hold tight to the string of a helium balloon only to have it escape and rise until it disappeared in the glare of the sun. Helium balloons want to rise, but launching a balloon ...

User comments : 0