Jupiter’s Great Cold Spot
Similar in size to the Great Red Spot, the patch is an auroral side effect
New images of Jupiter have revealed a Great Cold Spot, a colossal patch in the planet’s polar atmosphere which is 200 degrees cooler than its surroundings.
It’s thought that Jupiter’s aurorae are driving energy into the atmosphere, creating a region of cooling in the upper atmosphere that is 24,000km long and 12,000km wide, a similar size to the Great Red Spot.
“[The Great Cold Spot] changes dramatically in shape and size over only a few days and weeks, but it has re-appeared for as long as we have data to search for it, for over 15 years,” says Tom Stallard of the University of Leicester, who led the project. “That suggests that it continually reforms itself, and as a result it might be as old as the aurorae that form it – perhaps many thousands of years old.”
Jovian aurorae (left) are behind the cooler polar patch (right, marked with arrows)