Mar 2, 2011 16:00 GMT  ·  By
This image shows Discovery astronauts Drew and Bowen during the first EVA of the STS-133 mission
   This image shows Discovery astronauts Drew and Bowen during the first EVA of the STS-133 mission

Two astronauts from the crew of the space shuttle Discovery have gone outside the International Space Station (ISS) a couple of hours ago. They are conducting the second extravehicular activity (EVA) of the STS-133 mission to the orbital facility.

According to the crew aboard the ISS, the spacewalk debuted with a malfunction, when one of the two spacesuits that were to be used during the sortie was discovered to have a small leak.

The issue was however determined to be minor, and it only offset the astronauts' tight schedule by about 15 minutes. The NASA program showed that the EVA was supposed to start at 10:18 am EST (1518 GMT), Space reports.

The March 2 spacewalk is estimated to last for about six and half hours, and will conclude at 4:48 pm EST (2148 GMT), if everything goes according to schedule. The two spacewalkers have a large number of tasks to tackle, but experts say that they are doable within the allotted time frame.

Reports indicate that it was STS-133 crew member Steve Bowen's spacesuit that leaked just as he and NASA astronaut Alvin Drew were preparing to venture outside the ISS through the Quest airlock.

The leak was discovered during a routine check conducted by shuttle astronaut Mike Barratt (NASA) and ISS astronaut Paolo Nespoli, of the European Space Agency (ESA). They were helping Bowen into his suit outside the airlock.

After a series of checks, the crew members were able to determine that the air-scrubbing lithium hydroxide canister on Bowen's suit had a faulty seal. The astronaut's mind was never endangered during the incident, NASA says.

What the canister does is it helps remove carbon dioxide (CO2) from the air that is artificially circulated inside the spacesuit. The glitch discovered today was fixed when Barratt and Nespoli replaced the seal with a spare.

Discovery is on a 12-day mission to the orbital facility. It already delivered a new, zero-gravity storage room called Leonardo, and the humanoid robot Robonaut 2, which was developed by NASA and General Motors.

This is the final mission the spacecraft will ever fly. Once it returns to Earth, it will be decommissioned, and delivered to the Smithsonian National Air and Space Museum, in Washington, DC.