As it turns out, Betegeuse isn’t alone—it actually has a nearby companion star. The companion star appears blue here because, based on the team’s analysis, it is likely an A- or B-type star, both of which are blue-white due to their high temperatures. Processing: M. Zamani (NSF NOIRLab)The main clue that tipped astronomers off to the companion star came in the form of Betelgeuse’s luminosity intervals, also known as variabilities. After reviewing the star’s archival data, researchers recently proposed the longer secondary phase may be due to an external influence in the form of a companion star. Betelgeuse and its companion star were likely born at the same time, but their relationship won’t end well.