What happens when Betelgeuse blows its top?

This artist’s concept shows the red supergiant star Betelgeuse and a companion star orbiting within the supergiant’s tenuous outer atmosphere. Artwork: NASA, ESA, Elizabeth Wheatley (STScI); Science: Andrea Dupree (CfA) Betelgeuse has always been something of a mystery. And by “mystery,” I mean a source of endless fun, fascination and frustration for astronomers. Betelgeuse is one of the brightest stars in the sky, marking the right shoulder of the constellation Orion. It’s a red supergiant, a massive star with more than a dozen times the sun’s heft, that’s blasting out many tens of thousands as much light as our own...