( AFP ) - The Atlantis crew of seven examined the shuttle's heat shield one last time in preparation for returning to Earth, after a successful two-week mission to the International Space Station.
After Atlantis undocked from the ISS at 1442 GMT, Tuesday, co-pilot Lee Archambault flew the shuttle once around the orbiting station to take pictures of it and its newly installed and expanded solar wing array.
A few hours later, astronauts Patrick Forrester and Steven Swanson inspected the shuttle's heat shield with a high-definition camera mounted atop the shuttle's robotic arm.
The images were beamed to the National Aeronautics and Space Administration's Johnson Space Center in Houston, Texas, for close analysis. At first glance, no problems were detected, but a final evaluation was expected later Wednesday, NASA said.
Tuesday's inspection was carried out 74 kilometers ( 46 miles) from the ISS, in case the Atlantis needed to return to carry out additional repairs to its thermal covering, NASA said.
During an eight-hour spacewalk on Friday, the Atlantis crew repaired a hole in the thermal blanket that flapped opened as the shuttle blasted its way into orbit on June 8. Surgical staples were used to pin down the lose corner of the blanket.
NASA said the hand-size opening posed no threat to the crew, unlike the broken tile that caused the Columbia shuttle to break up on re-entry in February 2003, killing all seven astronauts on board and putting the shuttle program on hold for two and a half years.
Since the Columbia tragedy, inspections of the heat shield have become commonplace aboard all shuttle flights. The hole in the Atlantis' thermal blanket was spotted during an inspection before it docked with the ISS June 10.
Launched from Kennedy Space Center at Cape Canaveral, Florida, the Atlantis spent 10 days docked at the ISS.
During three spacewalks, a new 16-tonne truss was attached to the station enabling a new, vast, double-winged solar array that will boost the station's power-generating capacity so it can host new modules from Europe and Japan.
The astronauts also retracted the panels of another solar array for removal, installed a computer network cable to one of the station's units and performed sundry other jobs.
On Friday, the ISS crew also fixed two main computers aboard the ISS after an unprecedented 48-hour systems breakdown. Astronauts used a jumper cable to bypass a faulty power switch.
The mission was extended two extra days, allowing a fourth, unscheduled spacewalk to repair the torn thermal blanket.
The Atlantis delivered a new member for ISS Expedition 15. US flight engineer Clayton Anderson will remain four months aboard the station along with two Russian colleagues.
The shuttle brings home Sunita Williams, an engineer who has been on the station since December 10. She set a record Saturday for the longest uninterrupted space flight by a woman -- passing the previous record of 188 days and four hours.
She logged 29 hours and 17 minutes in four space walks during her trip, eclipsing the record held by astronaut Kathryn Thornton for most space-walk time by a woman.
And in April, Williams became the first astronaut to run a marathon in orbit -- on a treadmill, finishing it in four hours and 24 minutes.
The Atlantis is scheduled to land at Kennedy Space Center at 1745 GMT, Thursday.
Weather forecasters expect a rain-bearing low-pressure system to cloud over Cape Canaveral on Thursday and Friday, but NASA said the Atlantis has enough electrical power to remain aloft until Sunday if necessary.
As alternative landing sites, the Atlantis could also touch down at Edwards Air Force Base in California, or NASA's White Sands test facility, in New Mexico.