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We report on the direct detection and characterization of the probable redsupergiant progenitor of the intermediate-luminosity Type II-Plateau (II-P)supernova (SN) 2012aw in the nearby (10.0 Mpc) spiral galaxy Messier 95 (M95;NGC 3351). We have identified the star in both Hubble Space Telescope images ofthe host galaxy, obtained 17-18 yr prior to the explosion, and near-infraredground-based images, obtained 6-12 yr prior to the SN. The luminous supergiantshowed evidence for substantial circumstellar dust, manifested as excessline-of-sight extinction. The effective total-to-selective ratio of extinctionto the star was R'_V \approx 4.35, which is significantly different from thatof diffuse interstellar dust (i.e., R_V=3.1), and the total extinction to thestar was therefore, on average, A_V \approx 3.1 mag. We find that the observedspectral energy distribution for the progenitor star is consistent with aneffective temperature of 3600 K (spectral type M3), and that the star thereforehad a bolometric magnitude of -8.29. Through comparison with recent theoreticalmassive-star evolutionary tracks we can infer that the red supergiantprogenitor had an initial mass 15 \lesssim M_{ini} (M_sun) < 20. Interpolatingby eye between the available tracks, we surmise that the star had initial mass~17-18 M_sun. The circumstellar dust around the progenitor must have beendestroyed in the explosion, as the visual extinction to the SN is found to below (A_V=0.24 mag with R_V=3.1).

The Red Supergiant Progenitor of Supernova 2012aw (PTF12bvh) in Messier 95