Two spacewalking astronauts began a tricky battery swap on the space station's solar arrays Wednesday, a job that is expected to take two full spacewalks to complete.
Atlantis mission specialists Michael Good and Stephen Bowen got ahead of schedule, successfully installing more than half of the new batteries. In addition, they were able to fix a snagged cable that was plaguing a sensor camera on shuttle Atlantis and tighten the connection between a stuck antenna and its stand, Space.com says.
The shuttle's 12-day mission to the station most likely marks the last time Atlantis will be in orbit, as all space shuttles are slated to be retired by the end of 2010.
So far astronauts have completed two spacewalks to install new batteries and tighten bolts on the outside of the ISS. The shuttle crew is also delivering a new cargo module and a Russian-built mini research module, National Geographic reports.