CAPE CANAVERAL, Fla. (AP) -- "Let's light this fire one more time."

Those were the words of Commander Christopher Ferguson just before Atlantis blasted off on the final mission of NASA's 30-year-old space shuttle program.

Despite forecasts that called for rain and heavy clouds, Atlantis rose from the launch pad just two and a half minutes late at 11:29 this morning. Crowds of spectators estimated at nearly 1 million gathered at the Kennedy Space Center and surrounding towns, enjoying a 42-second view of the spacecraft before it disappeared into the clouds.

The crew of four will deliver a year's worth of supplies to the International Space Station and then haul away as much trash as possible. They are expected to spend 12 days in orbit.

With the launch of Atlantis on NASA's final space shuttle mission, President Barack Obama says a proud country watched as "America reached for the heavens once more."

Obama congratulated the Atlantis astronauts and space workers on what he called a "picture-perfect launch" Friday from Cape Canaveral in Florida.

Once Atlantis does return, thousands of workers in the shuttle program will be laid off, and it will be at least three years before astronauts are again launched from U.S. soil.

President George W. Bush announced the retirement of the shuttle and put NASA on a course back to the moon. But Obama canceled that in favor of trips to an asteroid and Mars.

Obama says he knows NASA is up to the challenge of sending Americans to Mars and he plans to be around to see it.