The Mysterious Great Dimming of Betelgeuse

The bright cool supergiant Betelgeuse became historically faint in February 2020. Various explanations have been offered for its unusual behavior - including conjectures this foreshadows an imminent supernova event. Direct imaging, spatially resolved spectroscopy, polarization measures, infrared, optical and ultraviolet spectra and more, help to unravel what happened to the star. New ultraviolet spectroscopic observations with HST/STIS made with spatial resolution across the disk during the last months of 2020 are reported in advance of the next optical minimum expected in the spring of 2021.