An accidental space telescope discovered why giant star Betelgeuse

Sign up to our free weekly IndyTech newsletter delivered straight to your inbox Sign up to our free IndyTech newsletter Sign up to our free IndyTech newsletter SIGN UP I would like to be emailed about offers, events and updates from The Independent. Read our privacy policy In late 2019, the red supergiant star Betelgeuse in the constellation Orion dimmed dramatically, leading astronomers to wonder if the massive star was about to explode in a supernova. Ground-based telescopes are blind or hindered certain infrared wavelengths where the contents of Earth’s atmosphere — such as water vapor — absorb light, the study authors note; Himawari-8 could watch Betelgeuse unfiltered. “Survey telescopes orbiting the Earth for non-astronomical purposes—such as the Himawari-8 meteorological satellite—have the potential to overcome these problems.” With steady observations of Betelgeuse in hand, the researchers conclude that a decrease in the star’s temperature and stellar dust belched out by the star contributed equally to the dimming first observed in 2019. This could be the result of a shock originating deeper inside Betelgeuse and working its way outward to perturb the stardust, the researchers note, and “this shock might be related to the triggering process of the Great Dimming.” As a red supergiant, Betelgeuse is more than 800 times the size of our Sun, and 10 to 20 times our Sun’s mass.