Betelgeuse, a massive red supergiant star, is on a path that eventually leads to its dramatic collapse into a supernova. When this happens, it could shine as brightly as the Moon for about two weeks, making it visible even during the day for months. However, predicting when this might occur is complex.
Recent observations have shown that Betelgeuse sometimes dims and brightens, leading to speculation about its imminent explosion. This variability might make it seem like the supernova is just around the corner, but the truth is less clear. The star is surrounded by dust and gas that can obscure our view, complicating our understanding of its behavior.
In 2024 and 2025, two independent research teams proposed that these brightness changes might be linked to a companion star, nicknamed Siwarha. This smaller star is thought to orbit within Betelgeuse’s atmosphere, affecting its brightness in a predictable cycle every 2100 days. This relationship sheds light on the star’s long periods of dimming and brightening, known as “long secondary periods,” which suggest that Betelgeuse might actually be part of a binary system.
Interestingly, the name Betelgeuse means “Hand of al-Jawzā,” coming from Arab astronomy. In a nod to its companion star, the name Siwarha means “Her Bracelet.” This connection reflects the star’s rich history in both science and culture.
In new research utilizing data from NASA’s Hubble Space Telescope, scientists tracked changes in Betelgeuse’s light for eight years. They discovered what appears to be the wake of Siwarha moving through Betelgeuse’s atmosphere. Andrea Dupree, an astronomer from the Center for Astrophysics | Harvard & Smithsonian, noted, “It’s like a boat moving through water,” hinting at the ripple effect created by the companion star. This observation strengthens the idea that Betelgeuse possesses a hidden companion that influences its behavior.
With this direct evidence, scientists can delve deeper into how massive stars evolve over time. For years, astronomers believed that Betelgeuse might have a companion, but this study offers solid proof. The team concluded that the companion star’s gravity focuses surrounding gas, forming a trail that influences Betelgeuse’s pattern of dimming.
As we wait for Siwarha to reappear in August 2027, this research opens a window into the mysteries of star evolution. Understanding how stars like Betelgeuse behave helps scientists predict their lifecycle, which culminates in explosive supernova events.
The findings highlight not only the fascinating dance between Betelgeuse and its companion but also remind us of the wonders of the universe waiting to be explored. For more detailed insights, you can read the original study on arXiv.
