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CAPE CANAVERAL, Florida - Nasa will try again tomorrow to bring the US space shuttle Atlantis and seven astronauts home after clouds and rain at its Florida landing site prevented a touchdown today.
The shuttle has been in orbit for 13 days to install a pair of solar power wings on the International Space Station and prepare the outpost for new laboratories built by Europe and Japan.
Touchdown at one of the Kennedy Space Centre's seaside runways in central Florida had been scheduled for 1.55pm EDT (5.55am NZ time), but the Kennedy Space Center was socked in by thick clouds and threatened by thunderstorms -- typical summer weather for the sultry subtropical Florida peninsula.
"We looked at it as hard and long as we think is reasonable," astronaut Tony Antonelli radioed from mission control to Atlantis commander Frederick Sturckow, explaining the decision to skip today's landing opportunities.
The shuttle has enough fuel and supplies to stay in space until Sunday, but it cannot land in rain because it could damage the thousands of ceramic tiles that protect the spaceships's belly from the fiery heat of re-entry.
Flight directors told Sturckow to lower the shuttle's orbit to add an extra landing opportunity on Friday at the backup runway at Edwards Air Force Base in California, should poor weather continue to dog Florida.
Weather questionable
Weather conditions at both sites are questionable, with more rain and clouds in store for Kennedy Space Center and high winds forecast for the shuttle's Mojave Desert site.
"We're going to be fighting the same challenges at KSC. At Edwards, the winds are going to pick up," Antonelli said. "We are going to try to land tomorrow," he added.
While Nasa battled weather on the ground, its Russian partners in the US$100 billion ($NZ133.28 billion) space station program wrestled with the outpost's balky computers.
The primary system shut down last week while astronauts were hooking up the station's new solar panels.
Station commander Fyodor Yurchikhin and flight engineer Oleg Kotov were able to bypass suspect circuitry and eventually revive the computers, which are needed to keep the station properly positioned in orbit.
The station crew disconnected two of the three computer systems on Thursday from the jumper cables used to bypass the circuits but failed to restart the network.
A third computer system remained operational.
The cause of the computer crash, which raised the prospect that the station might have to be temporarily abandoned, remains a mystery.
The Atlantis mission, which was delayed from March after the shuttle's external fuel tank was damaged in a hail storm in late February, is the first of four shuttle flights scheduled this year.
- REUTERS
