Betelgeuse is the bright orange-red star at the top-left corner of the constellation Orion. It’s one of the most famous stars in the sky and one of the closest red supergiants - about 650 light-years away. It’s also nearing the end of its life.
Red supergiants are stars dozens of times larger than the Sun, burning through their fuel at an incredible rate. They live only a few million years before collapsing in a colossal explosion called a supernova. Betelgeuse is in the very late stage of that process - it’s already swollen to about 700 times the diameter of the Sun. If you replaced our Sun with Betelgeuse, it would extend out past the orbit of Jupiter.
When Betelgeuse finally goes - astronomers think within the next 100,000 years, which is “any moment now” in cosmic terms - it’ll be visible from Earth as a single point of light brighter than the full Moon, easily visible during the day for weeks before slowly fading. It would also be one of the most spectacular shows humans have ever witnessed in the night sky.
