Post by Salem6 on Aug 9, 2005 14:36:36 GMT
The shuttle Discovery has touched down successfully in California after the first mission since 2003's Columbia disaster.
Discovery landed at Edwards Air Force Base at around 1312 BST (0512 PST; 1212 GMT) after bad weather forced a change to the intended Florida landing site.
Columbia broke up on re-entry because of damage it sustained when foam debris fell off the fuel tank during lift-off.
The crew are outside the vehicle and have been inspecting it on the tarmac.
"Congratulations on a truly spectacular test flight," astronaut Ken Ham from Mission Control in Houston told the crew after the shuttle came to a halt in the Mojave desert, "Welcome home friends."
Discovery's commander Eileen Collins replied: "Those are great words to hear. We're happy to be back and congratulate the whole team for a job well done."
Nasa officials cheered and clapped as Commander Collins made a perfect landing on runway 22 at Edwards Air Force Base about 54 minutes before dawn.
SHUTTLE LANDING SITES
Kennedy Space Center - the shuttle's "home" and preferred site for landing
Edwards Air Force Base - the shuttle has landed a total of 49 times at the base
White Sands - back-up known as Northrup Strip lies 45 miles north of US Army missile range
The shuttle touched down at around 322km/h (200mph), deploying its parachute to slow it down after making a 196-degree turn to align itself with the landing strip.
Its steep trajectory took it over the Pacific Ocean and just north of Los Angeles.
"It's going to be really hard to top this mission," Nasa's administrator Mike Griffin told reporters at a post-launch news briefing at Kennedy Space Center in Florida, "The crew performed fantastically well."
But the mission was by no means perfect. As with Columbia, foam debris broke free when Discovery was launched; onboard cameras captured multiple chunks being shed from the tank - one of which was only slightly smaller than the one that doomed Columbia.
Astronaut Steve Robinson also had to conduct an audacious spacewalk to remove two cloth gap fillers which were sticking out from beneath the vehicle.
Grounded fleet
Nasa has grounded the fleet until it has fixed the foam problem, so Discovery's visit to the International Space Station (ISS) may be the last shuttle mission for some time.
But officials wouldn't be drawn on when the next mission, which is still officially slated for September, would launch: "Until we get some data back, we can't make that decision. We will fly it when it's ready to go," said the shuttle programme manager Bill Parsons.
Eileen Thomas talks to astronaut Andy Thomas after exiting Discovery
At 1206 BST (0706 EST; 1106 GMT) on Tuesday, the orbiting shuttle began its return to Earth by fired its two Orbital Manoeuvring System engines for about two minutes 42 seconds and an altitude of around 329km (205 miles).
The shuttle started to experience the burning effects of the atmosphere at about 120km (75 miles), pitching down and then up so the protected underside was exposed to the most intense heating.
It hit the atmosphere at a speed of about 27,360km/h (17,000mph). Under certain circumstances, the shuttle's belly can be subjected to temperatures of 1,600C (3,000F) - hot enough to melt steel.
Discovery banked from side to side four times in order to lose speed.
Expensive return
Nasa will spend about $1m on returning the shuttle from California to Florida where its launches take place. It should be back in Florida in nine or 10 days.
Edwards Air Force Base was the second choice landing site. Rainstorms and lightning within 30 nautical miles (55.6km) of the Kennedy Space Center - the shuttle's "home" - forced Nasa to scrub the two available landing opportunities in Florida on Tuesday.
Discovery was due to land on Monday in Florida but bad visibility due to a deck of low-lying cloud forced a delay for 24 hours.
The situation aboard the shuttle meant Nasa were keen to bring Discovery down today.
A Nasa spokesman told the BBC News website that the crew only had enough consumables, such as food and water, to take them through Wednesday. The shuttle's ability to remove carbon dioxide gas from the crew decks were also due to run down after Wednesday.
Nasa has been extremely careful for the shuttle's return to Earth, looking for ideal weather conditions to make the shuttle's glide down through the atmosphere as trouble-free as possible.
news.bbc.co.uk/1/hi/sci/tech/4134986.stm