The lonely giant in Orion's shoulder has a hidden neighbor

Space · Published 25 October 2026 Swipe more like this →

In short: For a century, astronomers suspected that Betelgeuse—the massive red supergiant in our night sky—wasn't alone. They thought its erratic brightness might be caused by a hidden partner. In 2024, after 100 years of searching, scientists finally captured the clearest image of this elusive stellar companion.

Betelgeuse is a celestial titan. Its radius is approximately 700 times that of our Sun, meaning its volume could house more than 400 million Suns. Should it occupy the Solar System's core instead of our Sun, the star's outer layer would surpass Jupiter, turning Mercury, Venus, Earth, and Mars into gas. Despite its fame as the 10th brightest star in the night sky, its intense glow has historically made it nearly impossible to see anything orbiting nearby.

The hypothesis of a companion star, known as Betelgeuse B, was first proposed roughly a century ago to explain the star's periodic fluctuations in brightness and velocity. However, detecting it required overcoming extreme atmospheric blurring and the overwhelming light of the supergiant. Despite the lack of success from space-based tools, Miguel Montargès headed a group that utilised the European Southern Observatory's Very Large Telescope (VLT) during December 2024 to photograph the landmark scene.

The success of the mission relied on two 2024 studies that analyzed over 100 years of data to predict a narrow window of opportunity. The researchers determined that the maximum visible distance between the primary star and Betelgeuse B would occur in December 2024. The discovery revealed a surprise: Betelgeuse B is significantly more massive than originally estimated. While it was initially thought to be roughly the mass of our Sun, new observations indicate it has about two to three times the mass of the Sun.

This discovery is significant because it provides a new window into the lives of giant stars. Understanding the presence of Betelgeuse B may help scientists explain the supergiant's changing brightness and provide critical clues about its eventual supernova. It also serves as a testament to the power of ground-based technology, specifically high-resolution cameras like the 'Alopeke speckle instrument,' which can filter out atmospheric interference to reveal hidden cosmic secrets.

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