Abstract

Objects in telescope may be closer than they appear!

Through a combination of photometric analysis and clever, multi-timescale stellar modeling techniques, we find that the red supergiant Betelgeuse is closer, smaller, and less massive than previously thought. We use MESA stellar tracks and statistical techniques to infer that the star is in the midst of its core helium burning giant branch phase, which, in combination with estimates of its present-day mass, provides a rough constraint on its remaining lifetime before the onset of a cataclysmic event.

We identify a ~185 day overtone pulsation mode, constrain the physical process driving its quasi-annual (~400 day) variation, and restrict the set of plausible explanations for its extrinsic variability by examining its 100 year-long light curve and running grids of short-timescale, hydrodynamic simulations. Evolutionary and asteroseismic analyses allow us to derive the most precise radius reported to date and a distance via seismic parallax.