WASHINGTON, Sept. 15 (Xinhua) -- Two Atlantis astronauts successfully completed mission's third and final spacewalk Friday morning, according to a report from NASA's mission control center.

Mission specialists Joe Tanner and Heidemarie Stefanyshyn-Piper, the only woman in the Atlantis six-member crew, floated out of the airlock at 6:00 a.m. EDT. The duo also conducted the first spacewalk on Tuesday.

During the third spacewalk, which lasted six hours and 42 minutes, they performed a wide-range of activities from station maintenance to continued preparation of the orbital outpost's new truss segment.

The station's new solar arrays attached on the new truss structure were deployed on Thursday. They'll eventually double the space station's power capabilities and set the stage for future expansion.

The spacewalkers performed tasks that allowed flight controllers to deploy the radiator located on the newly installed truss. The radiator will remove heat from the station.

They also retrieved a materials exposure experiment from the station's exterior, installed a wireless TV antenna and replaced an antenna assembly on another truss.

Near the end of the spacewalk, Tanner and Piper conducted a test to evaluate infrared video of shuttle Atlantis' wing leading edge.

Atlantis will undock from the space station on Sept. 18, and landed at Kennedy Space Center in Florida next Wednesday, ending the 11-day mission crucial to the construction of the half-built orbiting outpost. Enditem