Discovery‘s six astronauts will learn on Sunday whether they have the final all-clear to fly home as analysts examined the space shuttle’s heat shield for potential micro-meteorite impacts.
Nasa declared Discovery‘s left wing free of damage on Saturday, hours after the shuttle undocked from the International Space Station (ISS).
Analysts were reviewing images of the shuttle’s right wing and nose cap recorded by the astronauts and were to announce on Sunday whether those areas suffered any damage from space debris, officials said.
”Right now they don’t see anything of concern at all, but I’ll get the final word tomorrow [Sunday] morning,” deputy shuttle programme manager John Shannon told reporters at the Johnson Space Centre in Houston, Texas.
”The left wing was completely cleared,” Shannon said.
Discovery is scheduled to land at the Kennedy Space Centre in Cape Canaveral, Florida, on Monday.
The late inspection for space debris hits, a first for shuttle missions, was added to Discovery‘s schedule as part of Nasa efforts to dramatically improve safety three years after the Columbia shuttle disaster.
Discovery separated from the ISS on Saturday after an intense nine-day stay that included three successful spacewalks aimed at improving shuttle safety and resuming construction of the orbiting laboratory.
The shuttle remained relatively close to the ISS so it can return to the station if serious damage is found.
The shuttle has already been declared free of damage that could have been caused by debris during the July 4 lift-off, just the second launch since the Columbia accident.
Columbia‘s heat shield was damaged by foam insulation that peeled off its external fuel tank during blast-off, causing the shuttle to break apart as it returned to Earth in February 2003 with seven astronauts on board.
Discovery‘s fuel tank shed a small amount of foam that did not damage the shuttle.
The two shuttle flights undertaken since the Columbia accident have been aimed at improving space flight safety before Nasa resumes regular launches to finish building the ISS by 2010, when the three-shuttle fleet is retired.
Nasa says the ISS is a key part of US ambitions to send astronauts back to the moon and eventually send the first manned mission to Mars.
Astronauts Mike Fossum and Piers Sellers successfully performed three key spacewalks, spending more than 21 hours outside to test shuttle repair techniques and fix equipment critical to the construction of the ISS.
Discovery also delivered more than three tonnes of clothes, food and research equipment to the ISS and will bring back about two tonnes of trash and broken equipment from the orbiting laboratory.
The shuttle also brought European Space Agency astronaut Thomas Reiter of Germany to the ISS, adding a third crew member to the orbiting laboratory.
”I can’t think of a better mission in recent history,” ISS programme manager Mike Suffredini said. ”It was an outstanding effort by both the shuttle and station teams. We are very proud.” – Sapa-AFP