Did you know there’s a star so massive it would swallow Jupiter? Meet Stephenson 2-18, a red supergiant located about 20,000 light-years from Earth, in the constellation Scutum. Its radius is estimated at roughly 2,150 times that of the Sun. To picture it: if the Sun were replaced by this star, Mercury, Venus, Earth, Mars, and Jupiter would all be completely swallowed inside it its surface would extend beyond Jupiter’s orbit, nearly reaching Saturn’s. Here’s the wildest part: its size is so extreme that it exceeds what theoretical models predict for stars like this, so astronomers still debate whether the real figure is truly that colossal or somewhat more modest.…