More recently, astronomers have proposed a theory for its volatile nature, which explains the star's seemingly erratic changes in brightness. They've suggested an unseen companion star orbiting Betelgeuse is periodically clearing dust out of the giant star's way to reveal more of its starlight.

Scientists have long speculated that Betelgeuse, one of the brightest stars in the night sky, is not alone. Now, thanks to the powerful Gemini North Telescope in Hawaii, astronomers suggest they’ve spotted Betelgeuse’s elusive companion —a smaller star in a tight orbit around it, both sitting at the shoulder of the constellation Orion.

Interest in Betelgeuse intensified during its great dimming in 2019-20 and subsequent resurrection. Among several explanations offered for the event was the possibility that a companion star, quickly nicknamed Betel-buddy, could be driving a six-year cycle in brightness. Now it seems the culprit has been found.

As it turns out, Betegeuse isn’t alone—it actually has a nearby companion star. The never-before-seen celestial object is detailed in two separate studies scheduled to publish on July 24 in The Astrophysical Journal Letters.

On Monday, a team of astronomers announced that they had spotted another star hewing extremely close to Betelgeuse. So close, in fact, that the second star plows through the tenuous outer atmosphere of the red supergiant.

Astronomers have confirmed the existence of a companion star in a tight orbit around Betelgeuse, resolving a long-standing mystery about the star’s varying brightness.