NASA observatory expected to fall to earth Wednesday

(CNN, KYMA) - A one and a half ton NASA observatory is falling out of orbit and toward Earth. NASA said the risk of the Swift Observatory harming anyone on earth is unlikely.

The spacecraft is expected to burn up as it blazes through Earth's atmosphere Wednesday morning.

NASA said it's possible some pieces could hit the ground or the ocean, near the equator.

The Swift Observatory launched in 2004.

It was originally designed to study the most powerful explosions in the universe, called gamma-ray bursts.

But, scientists have also used it to monitor other types of cosmic flashes, as well as asteroids and comets.