Space shuttle Columbia and its crew of seven returned to Earth in quiet triumph Thursday with a bounty of laboratory research on fire, metals and plants.

NASA’s oldest shuttle glided through a clear, flushed sky and touched down just after sunrise at Kennedy Space Center following a 16-day, 6.2 million-mile journey.

Commander James Halsell Jr. said it was satisfying to finally finish the job. The crew’s first stab at the science mission, three months ago, ended prematurely because of equipment trouble.

“We got all the science, plus more, that we were anticipating,” Halsell said after exiting Columbia. “It was great to be up there and it’s great to be home.”

A crowd of a few hundred welcomed the crew back. But the conversation, at the press site anyway, focused more on what was happening aboard Russia’s power-stricken Mir space station.

Indeed, Columbia’s entire flight was overshadowed by the far more dramatic events on Mir and Mars. The shuttle astronauts were informed of Mir’s latest misfortune shortly after landing.

“I think we added a lot to science, and we don’t feel upstaged,” astronaut Michael Gernhardt said. “We feel that we’re part of an overall space effort, of not only our country but the rest of the world.”

Unfazed by the meager publicity, the astronauts toiled round-the-clock on their second go-around.

This first-ever reflight, which began July 1 and cost NASA between $60 million to $70 million, experienced hardly any equipment trouble. The April mission was cut short after only four days because of a faulty power generator.

Shuttle program manager Tommy Holloway said the revamped Columbia performed “in an absolutely exemplary manner, and I could not be happier.”