Giant planet Jupiter is sporting a mysterious black eye, which astronomers believe is the scar from a powerful comet or asteroid impact. The dark spot, about the size of the Earth, suddenly appeared near the planet’s south pole and resembles markings left when a disintegrating comet hit Jupiter 15 years ago.
That string of impacts, seen here in a photo by Hubble, was predicted in advance as astronomers watched the comet, Shoemaker-Levy 9, break up to resemble a string of pearls. But the new spot in Jupiter’s cloudtops has come as a total surprise.
It was first spotted on Sunday by an Australian stargazer, Anthony Wesley, as he photographed Jupiter with his 14.5 inch telescope at Murrumbateman, near Canberra, New South Wales.
He wrote: “I’d noticed a dark spot rotating into view in Jupiter’s south polar region and was starting to get curious. When first seen close to the limb (and in poor conditions) it was only a vaguely dark spot, I thought likely to be just a normal dark polar storm.
“However as it rotated further into view, and the conditions also improved, I suddenly realised that it wasn’t just dark… it was truly a black spot.”
Wesley quickly ruled out the possibility that the spot might be one of Jupiter’s moon’s or their shadow because of its position. But he noticed that it was rotating at the same speed as other features on Jupiter, indicating that it was in the planet’s clouds.
Some of the world’s biggest telescopes are now sure to be turned on Jupiter as professional astronomers try to find out more about the dramatic event.
Jupiter lies at the edge of the asteroid belt and has such a powerful gravitational pull that it is known to alter the orbits of passing comets and asteroids.
Impact expert Dr Emily Baldwin, of Britain’s Astronomy Now magazine, said yesterday: “If there was a planet to get hit, Jupiter would be a prime target. And if it is an impact then it’s a chilling reminder that such events can still occur in our Solar System today.”
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