Spectral energy distribution fit to the dereddened photometry gathered from literature (symbols). The dashed line shows the 5 × 10⁵ L_⊙, 8500 K black-body (BB) input used for the model. The dotted line is the stellar and hot inner shell emission. The dot-dashed line shows the stellar and cool inner shell emission. The large spacing dashed line shows the outer shell emission contribution. We note that our models did not include the outermost cooler dust shell (18–40″) reported in Hutsemékers et al. (2013), and therefore do not reproduce the far-infrared photometry.