At 12:05 Eastern time today, a Delta 2 rocket carrying GLAST at its pinnacle blasted off from Cape Canaveral Air Force Station in Florida. After GLAST enters orbit, mission scientists will spend the next couple months switching on its systems and learning to interpret the data it collects.
NASA's new satellite is set to survey high-energy gamma rays across a broad swath, including a slice on the high end of that scale that has never before observed. Among the phenomena it is sure to witness: intense gamma-ray bursts—the brightest explosions known in the universe—popping like fireflies in the night sky as well as flaring galaxies driven by monster black holes within their cores. "GLAST enables scientists to look under the hood and see how the universe works," Steve Ritz of NASA Goddard Space Flight Center, the mission's lead scientist, said at a press conference Monday to announce the launch was a go.
Researchers hope GLAST will tell them something about dark matter, the unidentified stuff that seems to clump around visible galaxies, outweighing them by far. If dark matter consists of hypothetical particles called WIMPs (weakly interacting massive particles), it could spit gamma rays if WIMPs annihilate one another at the center of the galaxy where they would be most densely concentrated.