Using the European Southern Observatory's Very Large Telescope, astronomers have obtained the clearest image yet of Betelgeuse's previously suspected companion star, Betelgeuse B, potentially resolving a hundred-year-old cosmic mystery.
- Betelgeuse’s companion star is 2-3 times the Sun’s mass
- First clear image captured using ESO's VLT and SPHERE instrument
- Discovery may explain brightness variations and influence supernova timing
What happened
Astronomers led by Miguel Montargès from the Observatoire de Paris successfully imaged Betelgeuse’s elusive companion star, Betelgeuse B, using the ESO’s Very Large Telescope in Chile. This achievement marks the culmination of around 100 years of observations and hypotheses about potential stellar companions to this famous red supergiant.
The team took advantage of predictions about the companion’s position made in 2024, observing it at the moment of greatest apparent separation from Betelgeuse. Their data analysis revealed Betelgeuse B to be larger and more massive than previously assumed, estimated at about two to three times the mass of our Sun.
Why it feels good
This discovery is a testament to the power of technological advances and persistence in astronomy. Instruments like SPHERE, developed originally for exoplanet detection, have proven invaluable in uncovering new details about one of the night sky’s most recognizable stars.
Finding a companion star around such a well-studied celestial giant is a thrilling reminder that even familiar cosmic neighbors can still surprise us. It also offers deeper understanding of Betelgeuse’s brightness fluctuations, which have captured global attention due to their mysterious nature and potential links to a future supernova.
What to enjoy or watch next
Scientists plan further observations to confirm Betelgeuse B’s orbit by detecting it at predicted points in the coming years. This will strengthen the evidence for the companion and help refine models of the star system’s dynamics.
Meanwhile, astronomers will explore how Betelgeuse B influences the evolutionary path of the supergiant. This companion could play a role in the timing and nature of Betelgeuse’s eventual spectacular supernova, a cosmic event eagerly anticipated by both scientists and enthusiasts.