CAPE CANAVERAL, Fla. — Space shuttle Atlantis thundered away on its final voyage to orbit today, hoisting an experienced crew of six and a full shipment of space station gear.

Atlantis sped through a perfectly clear afternoon sky, blazing a trail over the Atlantic before huge crowds eager to catch one of the few remaining shuttle launches.

Its destination is the International Space Station, which was soaring over the South Pacific at the time of liftoff. The shuttle should catch up with the orbiting complex and its six residents Sunday.

More than 40,000 guests — the biggest launch-day crowd in years — descended on the Kennedy Space Center and the roads leading into it, all of them eager to witness Atlantis' last launch. The shuttle obliged, roaring off the pad right on time.

The only concern during Friday's countdown involved a small ball bearing found in Atlantis' payload bay earlier this week. Engineers scrambled to determine the bearing likely came from a spacewalk camera, and cleared the launch with just minutes remaining.

The 12-day mission is the last one for Atlantis, the fourth in NASA's line of space shuttles.