NASA's Swift Satellite Catches a Star being Exploded

When a gigantic star blows up, astronomers call it a "supernova." Over the past 100 years, astronomers have observed thousands of these explosions. But in every case, they were seeing the star after the explosion took place. They were seeing the hot debris from the explosion racing outward. It would be like seeing fireworks a few seconds after they go off, when the colorful lights are shooting away from the puff of smoke that mark the locations of the actual explosion.

On January 9, 2008, Alicia Soderberg and Edo Berger of Princeton University, in Princeton, N.J., were using Swift’s X-ray Telescope to observe a distant spiral-shaped galaxy known as NGC 2770. Suddenly, at 9:33 in the morning Eastern Time, the telescope picked up a powerful burst of X-rays coming from the galaxy. The burst lasted 5 minutes before it faded away.

The X-rays were due to a powerful blast wave bursting through the star’s outer layers, and blowing it to “Kingdom Come.” The blast wave itself was triggered deep inside the star, when the nuclear engine at the center ran out of fuel and collapsed. For decades, astronomers have been hoping to see such an explosion. And now, for the first time, they have actually seen what happens when a star goes supernova.

For years they have dreamed of seeing a star just as it was exploding, but actually finding one is a once in a lifetime event. This newly born supernova is going to be the Rosetta stone of supernova studies for years to come.

It was a gift of nature for Swift to be observing that patch of sky when the supernova exploded. But thanks to Swift's flexibility, they have been able to trace its evolution in detail every day since.