ALMA Reveals Betelgeuse's Hotspots Survive for Years, Defying Models

ALMA Reveals Long-Lived Hotspots on Betelgeuse's Bubbling Surface

New ALMA observations of Betelgeuse, the red supergiant in Orion, have captured its churning surface in unprecedented detail, revealing bright hotspots and an irregular, corrugated shape. The most striking finding: a prominent hotspot in the northeast appeared in nearly the same location and intensity in 2023 as it did in 2015, persisting for at least seven years—far longer than current models of stellar convection predict. The observations, made with ALMA's longest-baseline configuration, also show temperature variations up to 800 K and a surface that deviates from spherical by up to six percent, offering a rare glimpse into the dying star's final stages.