WASHINGTON - US space agency NASA said Thursday that its 11-year-old MESSENGER spacecraft will crash into the surface of Mercury, most likely on April 30, after it runs out of fuel.

The "spacecraft will impact the planet at more than 8,750 miles per hour (3.91 kilometers per second) on the side of the planet facing away from Earth," NASA said in a statement. "Due to the expected location, engineers will be unable to view in real time the exact location of impact."

Launched in August 2004, MESSENGER traveled 4.9 billion miles (7.9 billion kilometers) on a journey that included 15 trips around the sun and flybys of Earth once, Venus twice and Mercury three times.

The spacecraft began orbiting Mercury in March 2011. The four- year mission was blessed with many scientific findings, including one in 2012 that provided compelling support for the hypothesis that Mercury harbors abundant frozen water and other volatile materials in its permanently shadowed polar craters, and also helped test many technological achievements, including the development of a vital heat-resistant and highly reflective ceramic cloth sunshade that isolated the spacecraft's instruments and electronics from direct solar radiation, vital to mission success given Mercury's proximity to the sun.