EDWARDS AIR FORCE BASE, Calif. -- The commander of the Discovery mission says she thinks the most significant part of the mission was just getting the shuttle flying again.

Cmdr. Eileen Collins commented in a news conference with her fellow astronauts, after the shuttle safely touched down in California Tuesday.

After a journey of more than 5.8 million miles and 219 orbits, the space shuttle returned to Earth a continent away from where it took off.

Bad weather blocked two opportunities to land in Florida, so NASA officials ordered the shuttle to land at Edwards Air Force Base. NASA said it was the 50th landing at the base in the Mojave Desert.

"Congratulations on a truly spectacular test flight," Mission Control's Ken Ham radioed to Collins after she rolled to a stop on runway 22 at Edward.

Collins replied, "We're happy to be back."

She offered her congratulations to the whole team that made the mission possible.

President George W. Bush hailed Discovery's crew, saying its just-ended mission is an "important step" in NASA's bid to "regain the confidence of the American people."

It was America's first manned space flight since the Columbia disaster 2½ years ago.

Speaking to reporters at his Texas ranch, the president said Collins and co-pilot James Kelly did a "fantastic job" of guiding the craft back to earth.

"It was a great achievement," Bush said.

The flight, which started at the Kennedy Space Center on July 26, ended just after 8:11 a.m. EDT.

The landing included the characteristic twin sonic booms that are the hallmark of the slowing space shuttle as it drops toward a landing at a rate about 20 times greater than a commercial airliner.

At a news conference at the Kennedy Space Center, shuttle program manager Bill Parsons said, "I feel fantastic ... It's good to be us today."

NASA Administrator Michael Griffin said that, with the exception of five chunks of foam falling off the external fuel tank, the mission was a success.

"Everywhere you look was nothing but outstanding success," he said. "It's going to be really hard to top this mission."

Nobody could say, however, when the shuttle might fly again.

"We will fly each shuttle mission when it is ready to go," Griffin said.

NASA has said that it will not go up again until it determines what caused the foam problems. Griffin pointed out that the shuttle is necessary to complete the international space station.

The astronauts exited a crew vehicle a few hours after landing to walk around the spacecraft for a brief inspection. After that, Collins said the outside of the craft looks fantastic.

The Discovery crew will return to Houston on Wednesday.

NASA waved off two earlier landing opportunities in Florida earlier in the morning, just as it had done Monday. The plan shifted to the west after storms popped up just off the Florida coast.

Mission controllers called shuttle Collins just after 5 a.m. EDT Tuesday to ask how she felt about a landing in the California desert. At about 6:45 a.m., they gave a "go" for firing the orbiter's engines to slow it down as it falls out of orbit.

The burn started and ended on time. It trimmed 186 mph from the vehicle's velocity and started its fall toward the atmosphere.

It was the 50th shuttle landing at Edwards.

Sixty-one flights have touched down at Kennedy, and one early mission landed at the third possible site, a strip at the White Sands missile range in New Mexico. The abrasive gypsum sand runway contaminated Columbia's engines and the damage required extensive repairs.

The shuttle will now have to be prepared for a flight back to Kennedy Space Center. It will be mated to the top of a 747 for the transfer. At the conference, administrators said preparing for the flight would take seven or eight days and the flight home two more.

Mission Accomplishments

Discovery returned NASA to manned flight July 26 on what NASA sometimes described as a test flight. The crew resupplied the international space station and changed out a faulty gyroscope.

The crew has also used cameras and laser devices on robot arms to examine nearly every inch of the craft for damage. That was in response to some debris lost from the external fuel tank during launch, as well as the Columbia disaster in 2003.

Also during this mission, an astronaut was lowered under the orbiter for an unprecedented in-flight repair. Stephen Robinson removed some troublesome gap filler between some thermal tiles.

Griffin pointed out that the mission was the United States' 145th manned space flight, and that we're still learning how to do it.