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Using images from the Hubble Space Telescope (HST) and the Gemini Telescopewe confirm the disappearance of the progenitors of two Type II supernovae(SNe), and evaluate the presence of other stars associated with them. We findthat the progenitor of SN 2003gd, an M-supergiant star, is no longer observedat the SN location, and determine its intrinsic brightness using imagesubtraction techniques. The progenitor of SN 1993J, a K-supergiant star, isalso no longer present, but its B-supergiant binary companion is stillobserved. The disappearance of the progenitors confirms that these two SNe wereproduced by Red Supergiants.

The Disappearance of the Progenitors of Supernovae 1993J and 2003gd