CAPE CANAVERAL, Fla. -- For the second day, rain prevented Space Shuttle Atlantis from landing Friday at the Kennedy Space Center on its first try, leaving NASA managers to decide whether to prepare to land at a backup site in California instead.
"Our mindset down here is we're going to land you somewhere safely today," Mission Control told the shuttle crew Friday morning.
The landing attempt at California's Edwards Air Force Base would be at 2:49 p.m.
If the weather cleared up over Florida before then, NASA could instead try bringing the shuttle into Kennedy at 2:55 p.m.
"We're going to take a hard look at (Kennedy) at the next rev ... and we'll also be looking at Edwards," Mission Control told Atlantis' astronauts.
Despite the initial wave off, Atlantis' astronauts took two steps in preparation for landing - they put on their orange spacesuits and closed the shuttle's payload bay doors, which are kept opened during flights to keep heat from building up.
The crew has five chances Friday to land, the first had been at 1:18 p.m. in Florida and the last at 5:59 p.m. in California. If the weather spoils all those opportunities, mission managers would try again Saturday, with another backup landing site in New Mexico in the lineup.
The preferred landing site is Kennedy, where it is easier and far cheaper to get Atlantis to its hangar to be prepared for its next mission in December. If it lands in California, it would cost $1.7 million and take up to 10 days to get the shuttle home to Florida aboard a jumbo jet.
Atlantis has enough power for its systems to orbit until Sunday, but managers don't want to wait that long. The flight would be extended to Sunday only if technical problems needed to be fixed.
During Atlantis' two chances to land Thursday, showers were within 34 miles of the landing strip at Kennedy Space Center, and clouds hung below an altitude of 8,000 feet, both violations of flight rules.
During the crew's 14-day mission to the international space station, the astronauts installed a new truss segment, unfurled a new pair of power-generating solar arrays and activated a rotating joint that allows the new solar arrays to track the sun.
Originally scheduled for 11 days, the mission was extended by two days to give astronauts time to repair a thermal blanket that had peeled away during the June 8 launch. Astronaut Danny Olivas stapled it back into place during a spacewalk. An extra day in orbit was added after the weather in Florida prevented a landing Thursday.
The shuttle's visit to the space station was complicated by the crash of Russian computers that control orientation and oxygen production.
Atlantis helped the station maintain its orientation for several days until the computers were revived. Cosmonauts Fyodor Yurchikhin and Oleg Kotov used a cable to bypass a circuit board.