Astronomers using the Very Large Telescope in Chile have captured the clearest image yet of a companion star orbiting Betelgeuse. The discovery, published on July 28, 2026, confirms decades of suspicion about the red supergiant and reveals that the companion is two to three times more massive than the sun.
For roughly a century, astronomers stared at the night sky and suspected that the iconic red supergiant Betelgeuse was hiding a secret partner. That long quest reached a turning point when researchers captured direct observations revealing a faint stellar companion orbiting the famous star in the constellation Orion.
The breakthrough came from data gathered by the European Southern Observatory’s Very Large Telescope in the Atacama Desert region of Northern Chile. Using the SPHERE instrument—a system equipped with a coronagraph originally designed to spot exoplanets—astronomers peeled back the glare of the massive primary star to reveal what is now recognized as Betelgeuse B, also known formally as Siwarha.
How Advanced Exoplanet Tech Cracked a Century-Old Stellar Mystery
Betelgeuse has fascinated observers since antiquity. As a red supergiant nearing the end of its evolution, it is located roughly 650 to 700 light-years from Earth. For generations, scientists wrestled with the star’s complex brightness variations. While short-term pulsations happen every few hundred days, a longer six-year cycle remained stubbornly difficult to explain through internal mechanics alone.
The hypothesis of an orbiting companion gained serious traction when two papers published in 2024 predicted that the elusive companion star would reach its furthest orbital separation from Betelgeuse A in December of that year. Armed with that timeline, a research team led by Miguel Montargès of the Observatoire de Paris pointed the Very Large Telescope’s advanced optics at the target.
“Honestly, I thought we did not have the sensitivity to detect Betelgeuse B as it was predicted. Because it is more massive than predicted, we see it!”
Miguel Montargès, Observatoire de Paris
The processed data stunned the research team. Andrea Dupree of the Harvard-Smithsonian Center for Astrophysics, who was visiting the Paris Observatory when Montargès finished processing the files, recalled her colleague running into the room shouting, Oh my god, look! Look what I just found!
Montargès himself admitted he jumped from his chair upon seeing the final images.
Massive Surprise and the Formal Naming of Siwarha
The detection overturned initial theoretical models. Earlier estimates suggested the companion star possessed a mass roughly equivalent to our sun. However, the direct imaging data revealed that the companion is actually 2.6 to 3.1 times the mass of the sun, or broadly two to three times solar mass based on the team’s published findings in the journal Astronomy & Astrophysics.
Because the companion is significantly more massive and brighter than expected, it stands out clearly despite the overwhelming luminosity of the primary supergiant. The companion has already received the formal Arabic-derived name Siwarha, meaning her bracelet,
which nods to Betelgeuse’s traditional Arabic designation translating to the hand of the giant.
Co-author Anthony Boccaletti, also an astronomer at the Observatoire de Paris, highlighted the cross-disciplinary triumph of the imaging campaign. It is remarkable to see how SPHERE and advanced post-processing techniques, originally developed to find exoplanets, also excel at detecting a companion around a massive, evolved star like Betelgeuse,
he noted.
Separating Fact from Fiction After the Great Dimming
The discovery arrives after years of intense public and scientific scrutiny.
Confirmation Timeline and What Comes Next
Despite the clarity of the new portraits, the team remains rigorous about final confirmation. Because the companion’s orbit takes years to complete, astronomers want to track its movement completely across the system.
Montargès outlined the next observational milestone required to eliminate any remaining skepticism within the astronomical community. To be certain that the companion is really there, we still need to observe it in one year on the other side of the star, but there is very little space left for doubt,
he stated, pointing toward observations planned for late 2027 when Siwarha is expected to transit the opposite side of Betelgeuse.
Whether this companion will ultimately alter the evolutionary timeline or death of the red supergiant remains an open question for astrophysical modelers. For now, the successful capture of Betelgeuse B closes a century-long chapter of astronomical detective work and opens a new one regarding binary interactions among massive evolved stars.
Worth a look
