/ 21 August 2007

Shuttle heads home after successful mission

Nasa astronauts prepared on Tuesday to bring the space shuttle Endeavour back to Earth after a two-week mission to the International Space Station (ISS).

Endeavour is scheduled to land at the Kennedy Space Centre in Cape Canaveral, Florida, with two chances to touch down — at 16h32 GMT and 18h06 GMT, the National Aeronautics and Space Administration said.

The forecast was for mild weather and circumstances were ”generally favourable for a landing today [Tuesday] in Kennedy,” a Nasa spokesman said.

Landing had initially been set for Wednesday, but the US space agency rescheduled it for Tuesday fearing that its control centre in Houston, Texas, may have to be evacuated if it were grazed by Hurricane Dean, a category five storm that struck Mexico early Tuesday but missed Texas altogether.

If Houston orders the Florida landing, Commander Scott Kelly will fire the shuttle’s engines at 15h25 GMT to start the descent, Nasa said.

If the weather over Florida remains mixed, Endeavour has a second chance 90 minutes later again to land in Florida.

The five-man, two-woman crew awoke at 08h36 GMT, leaving about four hours for final preparations before the shuttle attempts re-entry into Earth’s atmosphere.

Mission control played the Simon and Garfunkel song Homeward Bound to wake up the astronauts.

”Good morning Endeavour, and the music this morning was set for all of you by all of your family in anticipation of a happy landing day,” said astronaut Shannon Lucile from the controls at Johnson Space Centre.

”Thank you, Shannon,” responded Kelly. ”Although it has been a short two weeks we accomplished a lot and we feel very much like coming home.”

Should landing here be called off, the shuttle would try again on Wednesday first at Cape Canaveral, or alternatively at Edwards Air Force Base in California, or possibly at the White Sands Space Harbour in New Mexico.

The Endeavour and ISS crews finished a shortened, fourth spacewalk on Sunday, before the shuttle with its crew of seven undocked from the ISS without performing the usual fly-past of the station to take pictures.

The crew put out a robotic arm with a high-definition camera and laser on the end to inspect the heat shield on Endeavour’s nose and wings for possible damage from meteors and other floating space debris.

Safety has been a big concern on space missions since 2003 when the shuttle Columbia disintegrated on re-entry due to a damaged thermal protection system. All seven astronauts died and missions were put on hold for two and a half years.

Endeavour sustained damage shortly after taking off on August 8 when a piece of foam that broke off the external fuel tank, possibly accompanied by some ice, hit the belly near the landing gear hatch 58 seconds after lift-off, leaving a small gash.

Astronauts inspected the damage during their stay at the space station and Nasa, after long deliberation, decided that it was not necessary to do risky repairs in space.

Nasa will not launch the next two shuttles planned in October and December of this year without first fixing the source of the foam problem, even if that means delaying the launches, shuttle programme manager Wayne Hale said.

In nine days at the space station, Endeavour crew and a US astronaut posted at the ISS, Clayton Anderson, made four spacewalks, installing a mechanical truss on the orbiting laboratory and fixing one of the gyroscopes that keeps it stable. They also delivered 2,7 tonnes of supplies. — AFP

 

AFP