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We present the discovery of a light echo from SN 2007af, a normal Type Iasupernova (SN Ia) in NGC 5584. Hubble Space Telescope (HST) images taken threeyears post explosion reveal two separate echoes; an outer echo and extendedcentral region, which we propose as an unresolved inner echo. Multiple imageswere obtained in the F160W, F350LP, F555W, and F814W using the Wide FieldCamera 3. If the outer echo is produced by an interstellar dust sheetperpendicular to the line of sight, it is located ~800 pc in front of the SN.The dust for the inner echo is 0.45 pc < d < 90 pc away from the SN. The innerecho color is consistent with typical interstellar dust wavelength-dependentscattering cross-sections, while the outer echo color does not match thepredictions. Both dust sheets, if in the foreground, are optically thin forscattering, with the outer echo sheet thickness consistent with the inferredextinction from peak brightness. Whether the inner echo is from interstellar orcircumstellar dust is ambiguous. Overall, the echo characteristics are quitesimilar to previously observed SN Ia echoes.

Detection of a Light Echo from the Otherwise Normal SN 2007af