Hubble Telescope Detects Wake of Betelgeuse’s Hidden Companion Star, Confirming Long-Held Theory

Astronomers have captured the clearest view yet of this intense turbulence triggered by a companion star orbiting a red giant dubbed Betelgeuse. Now, with new data from the Hubble Space Telescope, scientists have identified a dense ribbon of gas streaming through Betelgeuse's extended outer atmosphere, much like the wake left by a boat in water. Betelgeuse has long been a puzzle to astronomers because it often dims and then brightens again while changing shape. This previously unknown wake now has a physical explanation, indicating an unobserved companion star interacting with the giant star's extended atmosphere.

Hubble Detects ‘Boat-Like Wake' Revealing Betelgeuse's Hidden Companion Star

As per a NASA and Space.com report, the companion star, named Siwarha, was first identified in July 2025 within Betelgeuse's outer layers. But it was difficult to prove its existence without the direct evidence. New observations from the Hubble telescope, added to measurements made using ground telescopes in Arizona and the Canary Islands, showed a repeating cycle in Betelgeuse's light. This pattern matched the dense trail left behind as Siwarha moves through the red supergiant's atmosphere every six years.

Researchers mentioned the dense wake alters Betelgeuse's spectrum as Siwarha passes Earthward, like boat ripples revealing complex stellar interaction dynamics.

Betelgeuse's Stellar Disturbances Offer New Clues to Supernova Evolution

The findings are noteworthy because Betelgeuse is one of the few stars close enough to scientists for them to closely study such fluctuations. Learning how such material is disrupted and ejected informs scientists about the life cycle of massive stars and how they might ultimately explode as supernovae.

Siwarha will pass through Betelgeuse's atmosphere yet again in 2027, and astronomers plan to watch it at that time. The astronomers presented their findings at a meeting of the American Astronomical Society and detailed them in an article to be published in the Astrophysical Journal.