Posted: Sat, Jul 21, 2001, 10:23 AM ET (1423 GMT)

Two shuttle astronauts completed the installation of a new airlock module to the International Space Station during a four-hour spacewalk late Friday night. Astronauts Mike Gernhardt and James Reilly started the spacewalk at 12:35 am EDT (0435 GMT) Saturday and spent four hours and two minutes outside the station, installing a final nitrogen gas tank to the exterior of the Quest module. Gernhardt and Reilly used the Quest module to exit and reenter the station, marking the first time the new airlock module has been used to stage an EVA. The spacewalk went well, although it got off to a late start when the airlock depressurized more slowly than expected. With their work at the station nearly complete, the STS-104 crew will depart the station late Saturday night: undocking of Atlantis is scheduled for 12:54 am EDT (0454 GMT) Sunday. Atlantis will return to Earth with a landing at the Kennedy Space Center late Monday night.