After 100+ years of searching, NASA gets the clearest of image of Beltegeuse's companion
Scientists have long speculated that Betelgeuse has a companion. The stellar titan’s fluctuations in brightness and measured velocity provided clues to this. But Betelgeuse’s intense glow, for so long, made finding this companion star a near-impossible task.
However, a team of astrophysicists led by Steve Howell, a senior scientist at NASA, has cracked this long-standing mystery. While previous researchers unsuccessfully attempted to detect Betelgeuse’s companion using space-based telescopes, Howell and his team turned to a ground-based telescope.
Howell realized that the ground-based Gemini North telescope in Hawai’i, when combined with a specialized high-resolution camera, could potentially overcome atmospheric blurring to detect Betelgeuse’s hidden companion. The camera, officially called the ‘Alopeke speckle instrument, was able to capture thousands of rapid exposures of Betelgeuse. These snapshots helped the team track and correct for atmospheric interference through advanced image processing, revealing an image of Betelgeuse and its companion.
‘Alopeke is a high-resolution, dual-channel imager permanently installed at Gemini North, designed for capturing sharp, two-color optical images by minimizing atmospheric distortion. Using speckle imaging — a technique involving rapid exposures to counteract turbulence — it delivers diffraction-limited resolution from the ground, achieving space-like image clarity for targets as faint as 17th magnitude and offering both narrow and wide-field imaging modes.
Excited about the discovery, Howell described the combination as “a key to opening new observational windows.” He and his team named the newly-found companion “Siwarha,” meaning “her bracelet.”
The breakthrough not only solves a puzzle that has lingered for more than a century, but it also paves the way for future discoveries. Howell and his team plan to continue studying Betelgeuse and its companion. Their next prime opportunity comes in November 2027, when the companion will be at its greatest separation from the star.
