A new study just published shows that, within the past few hundred thousand years, it’s entirely possible that Betelgeuse ate and digested a whole other star.
This would explain at least one weird thing about it, and we know such stellar mergers can happen, so why not? It’s the least strange thing I’ve heard about Betelgeuse in the past couple of years anyway.
Betelgeuse is a red supergiant, a massive (roughly 15 times the Sun’s mass) star that’s nearing the end of its short life. Stars like this live for only some millions of years, and Betelgeuse is already about 8–10 million years old, so it doesn’t have much time left. It’s already run out of hydrogen in its core to fuse to helium, and is likely fusing helium into carbon, with a thin shell of hydrogen fusing outside of that. This produces prodigious amounts of energy, and the outer layers have reacted to that by swelling hugely (like a hot air balloon getting an infusion of heat); Betelgeuse is well over a billion kilometers in diameter.
Cropped part of the full-resolution image of Betelgeuse shows countless stars as well as a miasma of gas and dust in the background. ...