WASHINGTON, April 30 (UPI) -- After spending more than four years orbiting Mercury 4,105 times, NASA's MESSENGER probe dramatically ended its mission by smashing into the planet Thursday.
MESSENGER crashed into Mercury around 3:30 p.m., creating a crater on the surface estimated to be 50 feet wide, NASA said.
"Going out with a bang as it impacts the surface of Mercury, we are celebrating MESSENGER as more than a successful mission," said John Grunsfeld, associate administrator for NASA's Science Mission Directorate in Washington. "The MESSENGER mission will continue to provide scientists with a bonanza of new results as we begin the next phase of this mission--analyzing the exciting data already in the archives, and unravelling the mysteries of Mercury."
The probe transmitted its final image of the surface of Mercury -- gray and pock marked with craters -- about half an hour before its demise. The impact wasn't observable by terrestrial or space-based telescopes because it took place on the side of the planet away from Earth.
MESSENGER was launched Aug. 3, 2004, and reached Mercury on March 17, 2011. As part of its mission -- which was twice extended -- the probe determined Mercury's surface composition, discovered information about its geological history, found out its internal magnetic field is offset from its center and verified the planet's polar deposits are mostly water ice.
"Today we bid a fond farewell to one of the most resilient and accomplished spacecraft to ever explore our neighboring planets," said Sean Solomon, MESSENGER's principal investigator and director of Columbia University's Lamont-Doherty Earth Observatory in Palisades, N.Y. "A resourceful and committed team of engineers, mission operators, scientists, and managers can be extremely proud that the MESSENGER mission has surpassed all expectations and delivered a stunningly long list of discoveries that have changed our views--not only of one of Earth's sibling planets, but of the entire inner solar system."