DUST TO DUST: THREE YEARS IN THE EVOLUTION OF THE UNUSUAL SN 2008S

We obtained late-time optical and near-IR imaging of SN 2008S with the Large Binocular Telescope, near-IR data with the Hubble Space Telescope, and mid-IR data with the Spitzer Space Telescope. We find that (1) it is again invisible at optical (UBVR) wavelengths to magnitude limits of approximately 25 mag, (2) while detected in the near-IR (H) at approximately 24.8 mag, it is fading rapidly, and (3) it is still brighter than the progenitor at 3.6 and 4.5 mu m in the mid-IR with a slow, steady decline. The IR detections in 2010 December are consistent with dust emission at a blackbody temperature of T similar or equal to 640 K and a total luminosity of L similar or equal to 200,000 L-circle dot, much higher than the L similar or equal to 40,000 L-circle dot luminosity of the obscured progenitor star. The local environment also shows no evidence for stars significantly more massive than 10 M-circle dot, consistent with the progenitor being an 8-10 M-circle dot super asymptotic giant branch star.