For hottest planet, a major meltdown, study shows

In the scorching atmosphere of exoplanet KELT-9b, even molecules are torn to shreds. Massive gas giants called "hot Jupiters"—planets that orbit too close to their stars to sustain life—are some of the strangest worlds found beyond our solar system. New observations show that the hottest of them all is stranger still, prone to planetwide meltdowns so severe they tear apart the molecules that make up its atmosphere.

Called KELT-9b, the planet is an ultra-hot Jupiter, one of several varieties of exoplanets—planets around other stars—found in our galaxy. It weighs in at nearly three times the mass of our own Jupiter and orbits a star some 670 light-years away. With a surface temperature of 7,800 degrees Fahrenheit (4,300 degrees Celsius) - hotter than some stars—this planet is the hottest found so far.