The mobile service towers on Launch Pads 17-A (left) and 17-B (right) stand silhouetted against the pre-dawn sky at Cape Canaveral Air Force Station. In the background, the launch gantries are visible. Pad 17-B is the site for the launch of the Dawn spacecraft on June 30. Dawn's mission is to explore two of the asteroid belt's most intriguing and dissimilar occupants: asteroid Vesta and the dwarf planet Ceres.

Dawn will attempt to characterize the conditions and processes of the solar system's earliest time period by investigating in detail two of the largest protoplanets remaining intact since their formations. Ceres and Vesta reside in the extensive zone between Mars and Jupiter together with many other smaller bodies, called the asteroid belt. Each has followed a very different evolutionary path during the first few million years of solar system evolution.

Dawn will offer much in the form of images of varied landscapes on previously unseen worlds. including mountains, canyons, craters, lava flows, polar caps and, possibly ancient lakebeds, streambeds and gullies.

The Dawn spacecraft arrived at Astrotech Space Operations in Titusville, FL on April 10, 2007. Dawn is at the facility for final processing and launch operations.

"Dawn only has two more trips to make," said Dawn project manager Keyur Patel of NASA's Jet Propulsion Laboratory in Pasadena, CA. "One will be in mid-June when it makes the 15-mile journey from the processing facility to the launch pad. The second will be when Dawn rises to begin its eight-year, 3.2-billion-mile odyssey into the heart of the asteroid belt."

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--NASA and SPACE.com Staff

Credit: NASA/Amanda Diller