The Gamma-ray Large Area Space Telescope, or GLAST, rode a pillar of smoke and fire as it rocketed skyward from Florida at 12:05 p.m. EDT on the 11th. Now it's safely orbiting Earth at an altitude of 350 miles (560 km). The mission's engineers and scientists will give it a thorough checkout over the next two months, and the first observations from its instruments should come in about three weeks.
GLAST is designed to study the most energetic processes in the universe, such as the jets of superheated matter ejected from black holes and powerful explosions known as gamma-ray bursts. You can read about the instruments and their objectives here.