Space shuttle Atlantis closed in on the 120 million-mile (193-million-kilometer) mark as its final voyage neared an end and astronauts inspected their ship in advance of Wednesday's landing.

The laborious survey was carried out today using a newly repaired instrument that scanned Atlantis’ wings and nose for damage. NASA saved the inspection until the shuttle was flying free of the International Space Station.

Atlantis undocked from the space station yesterday for the last time, leaving behind a new 6-meter compartment loaded with supplies and six fresh batteries.

The shuttle program is ending in another several months, and Atlantis has no more missions lined up.

Before signing off, lead flight director Mike Sarafin radioed the astronauts and told them everyone was ecstatic with their work over the past 1 1/2 weeks.

“The ride out of the barn that you took with Atlantis, we did some math here on the ground,” Mr. Sarafin said. By the time Atlantis gets to Kennedy Space Center, “the odometer on Atlantis will have crossed 120 million miles,” he noted.

Atlantis will hit that magic milestone early Wednesday, just eight hours ahead of the scheduled 8:48 am (1248 GMT) touchdown.

Shuttle commander Kenneth Ham replied - 120 million miles is “pretty darn awesome in my mind”.

When Atlantis rocketed into orbit May 14, it had logged 115.7 million miles (186.2 million kilometers) in a quarter-century of flight. This trip would add 4.8 million miles (7.7 million kilometers) after 186 orbits of Earth if the shuttle lands on time.

At a news conference, Sarafin noted that it is possible Atlantis may set sail once more. “We’ll just have to see how the budget and schedule play out, given the direction that the agency has,” he said.

Unless the White House grants a reprieve, though, this is it for Atlantis. Only two more shuttle flights are scheduled, by Discovery and Endeavour. NASA officials will decide in another week or two whether the fall launch dates are feasible, or how long any delays might be, said LeRoy Cain, chairman of the mission management team.

As for Atlantis, Mr. Cain said time will tell whether this was its last flight. “I’ll know that for sure when Atlantis shows up in a museum somewhere,” he said.

“Until then, we're focused on this mission and taking them one at a time.”

NASA is under presidential direction to get out of the business of launching astronauts into orbit around the Earth and, instead, focus on sending them to asteroids and Mars. The Obama administration would like private business to pick up the slack.

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