Astronomers have watched baffled as a mysterious force breaks up an asteroid in deep space.
Asteroid P/2013 R3, which is located in the Solar System's main asteroid belt, broke up between 29 October 2013 and 14 January 2014.
The images of the collapse were captured by the Hubble Space Telescope, and look just like a comet when it breaks up on approach to the Sun.
The strange thing is that in this case there is no apparent reason why the asteroid has broken up.
The European Space Agency has said that nothing like it "has ever been observed before".
"This is a rock. Seeing it fall apart before our eyes is pretty amazing," said David Jewitt of UCLA.
Whatever is happening to the asteroid, it's pretty dramatic. Each of the four largest pieces are 200 metres wide each, and are slowly falling away from each other at about 1.5 km/hour.
ESA thinks there could be a number of causes - though all are just theories. It's possible that another asteroid hit it - though if that were try the pieces would be flying away from each other much more quickly.
It's also possible the rock is breaking up due to gas and ice pressure inside it - though the asteroid is too cold for that to happen, under most current theories.
There is also a chance that slow heating of different areas of the asteroid due to sunlight is breaking the rock apart. If true, observing how it works could be important -- breaking up an asteroid using the power of the sun has been discussed before as a potential way our ancestors might attempt to destroy an asteroid before it hits Earth.