Cape Canaveral, Florida, September 27, 2007—Smoke plumes around a Delta II rocket carrying the Dawn spacecraft appear to swaddle the craft in cotton in this picture taken just after Thursday's launch.

The rocket successfully lifted off at 7:34 a.m. eastern standard time, beginning a 3-billion-mile (4.8-billion-kilometer) journey to the heart of the asteroid belt. Dawn is scheduled to arrive at an asteroid known as Vesta in 2011 followed by a visit to the dwarf planet Ceres in 2015.

(Watch a video about the launch and get an overview of the Dawn mission.)

Dawn was making science fiction a reality even before takeoff. The exploration mission is NASA's first to use ion propulsion engines—a technology made famous by the TIE (twin ion engine) fighters in the Star Wars films. The highly efficient, basketball-size engines use electrically charged xenon gas to generate thrust.

"From such a little engine you can get this blue beam of rocket exhaust that shoots out at 89,000 miles [143,000 kilometers] per hour," Keyur Patel, NASA's Dawn project manager, told Space.com. "It is a remarkable system."

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