A massive asteroid 20 times larger than the one that wiped out the dinosaurs once slammed into Jupiter.
A giant asteroid crashed into Jupiter four billion years ago
Scientists have found evidence that the gargantuan meteorite crashed into the gas giant's moon Ganymede four billion years ago.
The impact was so big that it shifted Ganymede's axis altogether, experts at Kobe University in Japan say.
Questions about the asteroid crash still remain but experts are hoping to get some clarity when the European Space Agency's JUICE space probe visits Jupiter's moons in 2034.
Hirata Naoyuki, the lead author of the study, said: "I want to understand the origin and evolution of Ganymede and other Jupiter moons.
"The giant impact must have had a significant impact on the early evolution of Ganymede, but the thermal and structural effects of the impact on the interior of Ganymede have not yet been investigated at all.
"I believe that further research applying the internal evolution of ice moons could be carried out next."