Messenger spacecraft

This image of a "red spot" on Mercury, which is thought to be the result of a volcanic explosion, was sent to Earth by the Messenger probe in 2011.

Kill The Messenger: NASA Orbiter Crashes Into Mercury

5:36pm April 30, 2015

by Bill Chappell

Messenger was launched from Earth in 2004. After 4,104 orbits of Mercury and billions of miles of space travel, the orbiter ended its mission with a quiet bang Thursday.