The planet KELT 9b is so hot — hotter than many stars — that it shatters gas giant temperature records, researchers report online June 5 in Nature.
This Jupiter-like exoplanet revolves around a star just 650 light-years away, locked in an orbit that keeps one side always facing its star. With blistering temps hovering at about 4,300o Celsius, the atmosphere on KELT 9b’s dayside is over 700 degrees hotter than the previous record-holder — and hot enough that atoms cannot bind together to form molecules.