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The processes that shape the extended atmospheres of red supergiants (RSGs),heat their chromospheres, create molecular reservoirs, drive mass loss, andcreate dust remain poorly understood. Betelgeuse's V-band "Great Dimming" eventof 2019 September /2020 February and its subsequent rapid brightening providesa rare opportunity to study these phenomena. Two different explanations haveemerged to explain the dimming; new dust appeared in our line of sightattenuating the photospheric light, or a large portion of the photosphere hadcooled. Here we present five years of Wing three-filter (A, B, and C band) TiOand near-IR photometry obtained at the Wasatonic Observatory. These reveal thatparts of the photosphere had a mean effective temperature $(T_{\rm eff}$)significantly lower than that found by (Levesque & Massey 2020). Syntheticphotometry from MARCS -model photospheres and spectra reveal that the V band,TiO index, and C-band photometry, and previously reported 4000-6800 Angstromspectra can be quantitatively reproduced if there are multiple photosphericcomponents, as hinted at by VLT-SPHERE images (Montarges et al. 2020). If thecooler component has $\Delta T_{\rm eff} \ge 250$ K cooler than 3650 K, then nonew dust is required to explain the available empirical constraints. Acoincidence of the dominant short- ($\sim 430$ day) and long-period ($\sim 5.8$yr) V-band variations occurred near the time of deep minimum (Guinan et al.2019). This is in tandem with the strong correlation of V mag and photosphericradial velocities, recently reported by Dupree et al. (2020b). These suggestthat the cooling of a large fraction of the visible star has a dynamic originrelated to the photospheric motions, perhaps arising from pulsation orlarge-scale convective motions.

The Photospheric Temperatures of Betelgeuse during the Great Dimming of 2019/2020: No New Dust Required