Dawn mission headed for Sept. 26 launch

Dawn spacecraft arrived Tuesday at Pad-17B of the Cape Canaveral Air Force Station. Next stop - asteroid belt. NASA/Jack Pfaller

The Dawn spacecraft, mounted Tuesday atop a Delta II rocket, faces a final electrical system test on Friday. If the rocket and spacecraft pass Friday's tests, the faring will be installed and the Sept. 26 launch will be likely.

"If we get through that, we're probably going to launch," said NASA spokesman George Diller.

The Dawn spacecraft completed the 15-mile journey from Astrotech Space Operations in Titusville, Fla., to Pad-17B of the Cape Canaveral Air Force Station early Tuesday. The launch window for NASA's eight-year, more than 3.2-billion-mile odyssey into the heart of the asteroid belt, opens Sept. 26.

"From here, the only way to go is up," said Dawn project manager Keyur Patel of NASA's Jet Propulsion Laboratory in Pasadena, Calif., in a NASA interview. "We are looking forward to putting some space between Dawn and Mother Earth and making some space history."

Dawn's goal is to study the conditions and processes of the solar system's earliest epoch 4.5 billion years ago by investigating in detail the massive asteroid
Vesta and the dwarf planet Ceres, which are found between Mars and Jupiter in the asteroid belt.

Scientists theorize these were budding planets never given the opportunity to grow. However, Ceres and Vesta each followed a very different evolutionary path during the solar system's first few million years.

By investigating two diverse asteroids during the spacecraft's eight-year flight, the Dawn mission aims to unlock some of the mysteries of planetary formation. Dawn will be the first spacecraft to orbit an object in the asteroid belt and the first to orbit two bodies after leaving Earth, according to a NASA press release.













Dawn spacecraft just prior to mating with the third stage of the Delta II launch vehicle. The spacecraft will remain attached to the Delta until 1 hour and two minutes after launch. NASA photo.

The Sept. 26 launch window is 7:25 to 7:54 a.m. EDT. Dawn's launch period closes Oct. 15.