On the far-infrared excess of Vega

  title={On the far-infrared excess of Vega},
  author={Paul Michael Harvey and Bruce A. Wilking and Marshall K. Joy},
The Infrared Astronomy Satellite (IRAS) has recently detected a compact far-infrared emission source associated with Vega (α Lyrae)1. This flux appears to be thermal emission from dust heated by the visual/UV luminosity of Vega. Although circum-stellar dust is commonly associated with young, early-type stars2, the characteristics of the emission from Vega are quite atypical. The essential difference is the relatively low temperature of the dust for the observed source size. This low temperature… 
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