The first spacecraft to orbit Mercury, the closest planet to our Sun, will run out of fuel and crash on its surface Thursday, ending its 11-year mission.
The half-ton orbiter known by its acronym MESSENGER was launched in August 2004 on a mission to study Mercury’s chemical composition, geology and magnetic field.
MESSENGER spiraled through the inner solar system for seven years before reaching its destination. Inserting MESSENGER into orbit proved to be a challenging task, due to the sun’s gravity, intense heat and effects of solar radiation pressure.
WATCH: NASA video MESSENGER flies over Mercury
Among other scientific data, MESSENGER discovered the presence of frozen water in deep craters sitting in permanent shadow, as well as a mysterious dark material that could consist of organic compounds.
During its last month in orbit, MESSENGER sent back to NASA the best high-resolution images so far of Mercury’s desolate, moonlike surface.