A team of astronomers using the European Southern Observatory’s Very Large Telescope has found a binary star pair so close, their surfaces overlap. The stars orbit each other over the course of about 24-hours, with surface temperatures exceeding 40,000 degrees Celsius, making them the hottest and most massive “overcontact binary” that’s ever been discovered. It’s fortunate they were even observed, as systems like this don’t tend to last very long.
There are two ways this can end, and they’re both spectacular. In the first potential outcome, the stars merge into a single star that will collapse into one of the most energetic explosions in the universe: a long-duration gamma burst. Or if the stars have swapped enough stellar stuff, both could end their lives in supernova explosion.