Discovery crew wake for landing

[Guest Glenn]

Source: http://www.news.com.au/story/0,10117,19 ... 09,00.html

 

ASTRONAUTS on shuttle Discovery are making final preparations to land in Florida today after one last sleep in space.

 

It will bring to an end a mission NASA hopes has proved it can fly space shuttles safely again.

 

The crew are readying for a 9.14am EDT (2314 AEST) touchdown at Kennedy Space Centre, from which they launched on July 4.

 

If the shuttle cannot land at 9.14am, it will have a second chance at 10.50am EDT (0050 AEDT Tuesday).

 

After that, NASA will have to wait until tomorrow and possibly divert Discovery to Edwards Air Force Base in the California desert.

 

"Looking forward to a good day here and hopefully with good weather we will be on the ground here in about eight, 10 hours," flight commander Steve Lindsey radioed to Mission Control at Johnson Space Centre in Houston.

 

"We're hoping the same thing," flight communicator Steve Frick replied.

 

Later today, the astronauts will close the cargo bay doors on the shuttle, fire its rockets in a braking manoeuvre to start its descent from about 320km up and, just over an hour later, land in Florida.

 

Ther weather looked suitable for landing, although NASA said it was watching for rain showers that could cause a delay.

 

The shuttle had only enough oxygen to stay in space until Wednesday, NASA said.

 

The 13-day flight has been almost flawless, giving the troubled US space agency hope it is finally back on track after the 2003 Columbia disaster.

 

Discovery suffered no damage during launch, which was NASA's key goal, and crew members Piers Sellers and Michael Fossum, who made three spacewalks, performed a repair to the International Space Station critical to future construction of the half-finished $US100 billion ($133 billion) outpost.

 

The shuttle also dropped off German astronaut Thomas Reiter at the station, giving it a full three-person crew for the first time in three years.

 

Discovery launched amid controversy, with NASA's top safety officer saying it was not ready because of doubts that the problem that doomed Columbia had been fixed.

 

A wing heat shield on Columbia was cracked at launch by a chunk of insulating foam falling from the fuel tank, but no one knew it because there was no way to inspect the shuttle during flight.

 

Sixteen days later, the spacecraft disintegrated over Texas when fiery atmospheric gases penetrated the broken shield during its return to Earth. The seven astronauts on board were killed.

 

The flyaway foam problem showed up again on a subsequent shuttle flight last year but after further changes, the shuttles' fuel tank shed only small bits of the insulation during the July 4 launch.

 

Extensive in-flight inspections with cameras and sensors on the shuttle's robot arm found the flecks had done no harm and Discovery was pronounced to fit to withstand the scorching return to Earth.

 

Sellers and Fossum also tested techniques to reach and repair heat shield damage should it occur.

 

NASA has spent $US1.3 billion ($1.73 billion) on safety upgrades since Columbia.

 

The space agency plans to fly 16 shuttle missions to finish the International Space Station, which is sponsored by 16 nations.

 

Its next flight is due to launch about August 28.