EDWARDS AIR FORCE BASE, California, May 24, 2009 (AFP) - The space shuttle Atlantis made a picture perfect landing in Calfornia Sunday, nearly two days behind schedule at the end of a successful mission to repair and upgrade the Hubble telescope.
Heat waves rise as astronauts wait to exit Space Shuttle Atlantis after landing in the Mojave Desert May 24, 2009 (AFP photo)
Bypassing Florida because of uncertain weather conditions, the shuttle and its crew of seven landed at this desert air base 160 kilometers (100 miles) northeast of Los Angeles after 12 days, 21 hours and 37 minutes in flight.
"Congratulations on a very successful mission giving Hubble a new set of eyes that will continue to expand our knowledge of the universe," said mission control in Houston as it welcomed the US astronauts back to Earth.
"It was a thrill, from start to finish. We had a great ride," said co-captain Gregory Johnson.
Upon landing, shuttle commander Scott Altman thanked everyone for getting them home safely.
"At last! I didn't realize it was going to be so hard to get back to the Earth," he said.
"We're all thrilled to have the mission complete and it was a testament to the teamwork and cooperation of folks all across the country."
Atlantis blasted off on May 11 on what was scheduled to be an 11-day mission to repair the Hubble Space Telescope and extend its range and life for another five years.
It circled the Earth 197 times before finally making the flawless descent to Edwards, touching down at 8:40 am local time (1540 GMT) and deploying a parachute to break its momentum.
Bad weather including crosswinds pushed back Florida landing tries for three days before US space agency NASA finally opted for the California landing. The craft had enough fuel and supplies to be aloft until Monday at the latest.
A Florida landing would have saved NASA the two million dollars it will cost to transport the shuttle from California to Cape Canaveral on the back of a Boeing 747 jet.
With storms not too far from the Florida space center, the Houston, Texas control center asked the seven astronauts to take another whirl around Earth, hoping that weather conditions would improve.
But as the skies failed to clear enough for a Florida green-light, the landing was set for sunny California.
Under NASA rules, a decision on whether to attempt a landing has to be made one and a half hours before the planned touchdown. Once the crew begins its descent toward Earth, the decision cannot be reversed because the shuttle lacks engine power that would allow it to regain altitude.
NASA has set several conditions for a landing: the cloud cover must not be more than 50 percent, visibility must be at least eight kilometers (five miles) and lateral winds must not be blowing at more than 28 kilometers an hour (17 miles an hour).
As early as Thursday, the astronauts were told by NASA to shut down some of the computers on board the shuttle to conserve electricity in the event their landing was delayed.
The Hubble observatory was released back into its orbit on Tuesday after five obstacle-filled spacewalks.
The enhancements have equipped the delicate stargazer to search for the earliest galaxies, probe the mysteries of dark matter and dark energy as well as study planet-making processes.
John Grunsfeld, an astronomer turned astronaut who led three of the mission's five spacewalks, this week hailed the Hubble as "probably the most significant science instrument of all times."
The telescope is expected to resume operations in three weeks.
The mission was not without risks. The crew escaped satellite debris and meteorites, which are more prevalent at Hubble's 560-kilometer (336-mile) altitude than the typical shuttle orbits.
It was the 126th space shuttle mission since 1981. NASA plans to make eight more flights before ending the shuttle program in September 2010. Besides Atlantis, NASA has the shuttles Endeavour and Discovery.
While the Atlantis crew was gone, President Barack Obama tapped Charles Bolden, a former astronaut who piloted the shuttle that deployed Hubble into orbit in 1990, to lead the space agency.
If confirmed, the retired Marine Corps major general would be the first African-American to head NASA and only the second astronaut.
Upon the shuttle's successful return to earth, NASA space shuttle launch director Mike Leinbach congratulated the crew of the space shuttle Endeavour, who had been standing by throughout Atlantis' mission just in case they were needed for an audacious rescue mission.
Leinbach also said, according to a statement, that the space agency was aiming for a June 13 launch for Endeavour's next mission to the International Space Station.