 Gamma Cassiopeia is a blue-white sub-giant variable star. It's 19 times more massive and 65,000 times brighter than our Sun. The radiation of Gamma Cassiopeia is so powerful that it even reflects IC63, sometimes nicknamed the Ghost of Cassiopeia, that lies several light years away from the star. The colors in the nebula showcase how it's affected by the powerful radiation from the distant star. It is both an emission nebula, red, from hydrogen excited by Gamma Cassiopeia, and a reflection nebula, blue, with reflection light from Gamma Cassiopeia.