Artist’s animation of Betelgeuse and its dusty veil

This artist’s animation shows a close-up view of Betelgeuse’s irregular surface — with its giant, dynamic gas bubbles — and distant stars dotting the background. As the “virtual camera” rotates from right to left we see a dusty clump, which condensed from gas released by the star, obscuring the southern region of Betelgeuse from different vantage points.

When the red supergiant star Betelgeuse became visibly darker in late 2019 and early 2020, astronomers were puzzled. Thanks to a new study conducted with ESO telescopes, we now know that Betelgeuse’s dip in brightness was the result of a  “dusty veil” that formed from material that emerged from the star, partially concealing its southern region. The new research shows that the star likely ejected a large gas bubble that moved away from it; when a patch of the surface (in dark in the animation) cooled down shortly after, that temperature decrease was enough for the gas to condense into solid dust.