After roughly a century of suspicion, astronomers have finally gotten a clear look at the star that’s been hiding beside Betelgeuse. Using the European Southern Observatory’s Very Large Telescope, a team led by French astronomer Miguel Montargès captured the clearest image yet of Betelgeuse B, and the results surprised even the researchers who found it.
A Century-Old Hunch, Finally Confirmed
Betelgeuse, the red supergiant marking the shoulder of Orion, has puzzled astronomers for roughly a century with its regular changes in brightness — a pattern that hinted at an orbiting companion star nobody could actually see. The star is so enormous and so bright, roughly 1,000 times the size of the Sun, that any nearby companion would normally be lost entirely in its glare. “I thought we did not have the sensitivity to detect Betelgeuse B as it was predicted,” Montargès said. “Because it is more massive than predicted, we see it.”
Heavier and Brighter Than Anyone Expected
Earlier estimates put Betelgeuse B at roughly the mass of the Sun. The new observations, made by borrowing imaging techniques originally developed to hunt exoplanets, suggest the companion actually carries two to three times the Sun’s mass. The team observed Betelgeuse in December 2024, the point when models predicted the companion would sit at its greatest apparent distance from the supergiant — giving them the clearest possible shot at separating its faint light from Betelgeuse’s overwhelming glow. “These are among the best moments in science: seeing something new, unexpected,” Montargès said.
What Happens to a Companion Star Orbiting a Dying Giant?
Betelgeuse is a red supergiant nearing the end of its life, expected to eventually go supernova. Researchers now want to know whether Betelgeuse B could influence how that plays out — and separately, some models suggest the companion itself may eventually be swallowed by the supergiant, possibly within the next 10,000 years. A follow-up observation is planned for roughly a year from now, catching the companion on the opposite side of its orbit, to further confirm the detection. As Montargès put it, “there is very little space left for doubt.”
Bottom Line
Betelgeuse is one of the most stared-at stars in human history, visible to the naked eye and studied for thousands of years — and it just proved there was still a genuine surprise left in it. Confirming Betelgeuse B closes a century-old mystery about the star’s strange brightness cycles, and opens a new one about what a close companion means for how a dying supergiant eventually meets its end.
FAQ
Can I see Betelgeuse without a telescope?
Yes. Betelgeuse is one of the brightest stars in the night sky and is easily visible to the naked eye in the constellation Orion, marking the hunter’s shoulder.
How far away is Betelgeuse?
Estimates place it roughly 400 to 650 light-years from Earth, making it one of the closest red supergiants to our solar system.
Is Betelgeuse about to explode?
Not on any predictable human timescale. It will eventually go supernova, but that could happen anywhere from tomorrow to 100,000 years from now on astronomical timescales — there’s no way to pin down an exact date.
