Betelgeuse and wake of its companion star (artist's concept)

Using new observations from the NASA/ESA Hubble Space Telescope and ground-based observatories, astronomers tracked the influence of a recently discovered companion star, Siwarha, on the gas around Betelgeuse. The research reveals a trail of dense gas swirling through Betelgeuse’s vast, extended atmosphere, shedding light on why the giant star’s brightness and atmosphere have changed in strange and unusual ways.

This artist’s concept shows the red supergiant star Betelgeuse and an orbiting companion star. The companion, which is orbiting clockwise from this point of view, generates a dense wake of gas that expands outward. It is so close to Betelgeuse that it is passing through the extended outer atmosphere of the supergiant. The companion star is not to scale; it would be a pinprick compared to Betelgeuse, which is hundreds of times larger. The companion’s distance from Betelgeuse is to scale relative to the diameter of Betelgeuse.

The results of the new study were presented at the 247th meeting of the American Astronomical Society and are accepted for publication in The Astrophysical Journal. More details about this new result can be read here.

[Image description: An illustration of the red supergiant star Betelgeuse, its companion star, and a dense wake. The disk of a red-orange star is in the center. It is surrounded by a diffuse orange cloud representing its extended atmosphere. Below it, about one stellar diameter away, is a yellow dot representing a smaller companion star. From the companion, a dark red cloud wraps around in a counterclockwise direction. It begins very narrow and expands as it gets further from the companion, finally disappearing at the outer edge of the diffuse orange cloud. The words “artist’s concept” are at lower right.]