Space shuttle Discovery returned to Earth on Friday, bringing home the last American to live aboard Mir and closing out three years of U.S.-Russian cooperation aboard the aging space station.

Although NASA had lasagna and Oreo cookie ice cream waiting for American astronaut Andrew Thomas - he put in the order days ago - he was too tired and sick to eat."Returning to gravity was a bizarre experience after being so long in weightlessness," a NASA spokesman quoted Thomas as saying. "I felt like I had bags of weights on my arms and legs."

His body weakened by 4 1/2 months in zero gravity, Thomas was carried from Discovery on a reclining seat and taken to Kennedy Space Center's crew quarters, where he underwent a slew of medical tests. He attempted a few steps but soon realized "I was very tired and wanted to just lie down and be quiet for a while."

Eight hours after landing, Thomas still was lying down, nibbling on a bagel.

"He said he hadn't had anything to eat in 13 hours, so that's all he felt like trying right now," explained NASA spokesman Bruce Buckingham.

The 46-year-old unmarried engineer was the seventh NASA astronaut to live on Mir as practice for the international space station; he boarded the Russian outpost in January.

All together, the six men and one woman racked up 977 days in orbit beginning with the first expedition in 1995, and endured a raging fire, a near-catastrophic collision, computer breakdowns, power outages and toxic leaks.

NASA Administrator Daniel Goldin greeted Thomas with a bouquet.

"He's getting a big hug from me because he did a terrific job and he maintained his mild manner," Goldin said.

NASA shuttles linked up with Mir nine times over the past three years. The Russians plan to let Mir burn up in the atmosphere by the end of 1999, when it will be 13 years old, and concentrate instead on the international space station, the first piece of which should be in orbit by November.