As extreme exoplanets go, this is a wild one: Astronomers have discovered a brown dwarf which is hotter than our sun by more than 3,000 degrees Fahrenheit. Brown dwarfs are halfway between planets and stars, and are sometimes called failed stars because they aren't massive enough to fuse hydrogen in their cores.
This particular brown dwarf, called WD 0032-317 B, is one of the most massive discovered to date with a mass between 75 and 88 times that of Jupiter. It was originally observed in 2019 and 2020, and recent follow-up observations revealed its extreme character.
It is also tidally locked, meaning one side of the brown dwarf always faces its star and is much hotter than the other. The hot side, called the dayside, is a mind-bending 10,000 degrees Fahrenheit hotter than the cooler side, called the nightside.