Betelgeuse is a red supergiant. With a diameter 1000 times that of the Sun’s and – formerly – 10,000 times the illuminance, it has wowed the entire Milky Way, but now it’s even being mentioned on the cable news shows. Why? Because everyone’s hoping for a catastrophe. If such a large star fades to 36 percent of its previous illuminance within a short time, it would suggest it might soon end in a supernova. That would certainly be spectacular, because it would grace the Earth’s night skies with the brightness of a half moon.
But the hope that this fireworks display will go off sometime in our lifetime is probably still too premature. Astronomers of the European Southern Observatory have shown with the help of the Very Large Telescope that Betelgeuse really has changed in apparent shape and brightness (see the images below). But that could also be due to a giant dust cloud ejected by the star, which is more than 700 light-years away, obscuring our view. It could also be possible that the surface has cooled significantly due to some unusual stellar activity.