Top panel: two-component black body fits to the SED of AT 2010dn obtained from optical to MIR at the epoch of +30.6 days. Bottom panel: single black body fit for AT 2010dn in the MIR domain at very late phase of +1332.5 days. Although this fit could reproduce the late MIR data, the fitted temperature should be considered as an indicative value. The MIR measurements were obtained from the Spitzer Space Telescope + IRAC images at 3.6 μm and 4.5 μm.