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Multiple ultraviolet spectra of the nearby red supergiant comma Betelgeuse comma using STIS will enable unique spatially resolved measures of photospheric and chromospheric structure and mass inflows and outflows. This follows the historic dimming of the star captured by HST-STIS in 2019-2020 comma and will probe the unusual atmospheric structure following the dimming event. An HST campaign of 2 cycles will be complemented by multi-frequency photometry comma spectroscopy comma interferometry and polarimetry at radio comma infrared comma and optical wavelengths in order to map surface structures and their variability comma and the extended outer atmosphere over both the short (420-day) and long comma secondary (2000-day) periods of this supergiant. These observations comma coupled with detailed modeling and simulations. will probe the structure comma dynamics comma and mass loss from Betelgeuse to provide crucial insights into the atmospheric physics and wind-driving mechanisms of red supergiants.