MESSENGER
Depiction of the MESSENGER spacecraft flying over Mercury's surface, displayed in enhanced color. NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

NASA's Messenger space probe crashed into the surface of Mercury on 30 April after running out of fuel, ending its 11-year mission.

Scientists had projected that it would hit the surface of the planet at 8,750 miles per hour and create an impact crater 52 feet (16 metres) in diameter.

They documented Messenger's final hours on Twitter, writing: "Well, I guess it's time to say goodbye to all my friends, family, support team. I will be making my final impact very soon."

The crash wasn't visible from Earth because it occurred on the far side of Mercury.

Mission controllers confirmed that the probe had crash-landed at 3:26 pm EDT (7:26pm GMT).

"A NASA planetary exploration mission came to a planned, but nonetheless dramatic, end on Thursday when it slammed into Mercury's surface at about 8,750 miles per hour and created a new crater on the planet's surface," the agency said in a statement.

The Messenger (an acronym for MErcury Surface, Space ENvironment, GEochemistry, and Ranging) was the first ever spacecraft to orbit the closest planet to the Sun.

Since it was launched in 2004, it travelled 8.73 billion miles, and acquired over 289,000 images.

It completed 4,100 orbits of Mercury since it started to orbit the planet on 18 March 2011, and made the significant discovery of frozen water in its permanently shadowed craters.

"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 - analysing the exciting data already in the archives, and unravelling the mysteries of Mercury."