Astronomers begin to go the distance with gamma-ray bursts
Just before 10 p.m. EDT, last Sept. 3, Dan Reichart's cell phone started playing "The Stars and Stripes Forever." A fitting tune, since it was heralding a call from the heavens. Reichart's phone was signaling that a detector on NASA's Swift satellite had registered a gamma-ray burst, the most powerful type of explosion in the universe. Such bursts—none of which lasts longer than a few minutes—typically mark the violent death of a massive star as it collapses to become a black hole.