14 DAY TRIAL // Astronauts aboard the International Space Station (ISS) and the space shuttle Discovery are getting ready to perform the first extravehicular activity (EVA) of the STS-133 mission. Two astronauts will go outside the station to perform vital repairs and upgrades.
The spacewalkers, both of them ascended to orbit on Discovery's final flight ever, will be in charge of upgrading the station's power extension cables, and to perform a number of other tasks laid out by Mission Control.
According to the official flight manifest, the spacewalks is due to begin today, February 28, from the Quest airlock. Exit is planned to take place at 11:18 am EST (1618 GMT), Space reports.
NASA experts estimate that the EVA will last around six and a half hours. This is the first of two planned spacewalks for the STS-133 mission. Astronauts Steve Bowen and Alvin Drew will be conducting the sortie.
Bowen, who will be wearing a spacesuit adorned with red stripes during the spacewalk, is an experienced astronaut. He replaced former STS-133 crew member Timothy Kopra, who injured himself less than six weeks before Discovery launched.
This will be the first EVA for Drew, who will be wearing a solid white spacesuit. He never participated in a spacewalk, but this new mission is Bowen's fifth, so he brings extensive experience to the mission.
The team will receive additional directions from Kopra during the flight. The former STS-133 member will be keeping in touch with his colleagues in orbit from Mission Control, at the NASA Johnson Space Center, in Houston.
The primary goal of today's sortie will be to install a new extension cable between the Unity and Tranquility modules on the ISS. The cable will also act as a contingency power source in case of emergency.
During the spacewalk, the two astronauts will also remove the ammonia pump that broke down in August 2010, and that was temporarily stored at a location on the exterior of the ISS.
Additionally, they will also retrieve two tool bags left behind during a previous sortie, which they will use during the second EVA to vent out excess ammonia from the tank they will move today.
The reservoir needs to be prepared for return to Earth, aboard space shuttle Atlantis, in June. NASA engineers are keen on analyzing it, so that they can figure out what went wrong last year.
The second spacewalk of the STS-133 mission is scheduled to take place on Wednesday, March 2.