Does Jupiter really protect us from cosmic impacts? © Getty Images

Does Jupiter really protect us from cosmic impacts?

There has been little proof to the long-held claim that Jupiter's powerful gravity helps deflect incoming debris, but do simulations show Jupiter playing protective big brother to Earth?

Asked by: Anonymous


Astronomers have long believed that the powerful gravity of Jupiter helps deflect incoming comets away from the Earth. Until recently, however, there was little hard evidence to back up this comforting belief. But using computer simulations, Dr Jonti Horner of the University of New South Wales, Australia, and Professor Barrie Jones of the Open University, have now tested the idea and found that, contrary to the textbook claims, Jupiter actually increases the risk of a cosmic impact on Earth. The simulations reveal that while the giant planet does a good job of deflecting comets that come from far beyond our Solar System, it actually drives more nearby comets and asteroids onto a collision course with the Earth, boosting the overall rate of impact.


Subscribe to BBC Focus magazine for fascinating new Q&As every month and follow @sciencefocusQA on Twitter for your daily dose of fun science facts.