OPTICAL IMAGING OF THE LOW REDSHIFT SUPERLUMINOUS QSO 1821+643

We present optical imaging of the luminous, z = 0.3 QSO 1821 + 643, with resolution 1.0 and 0.4 arcsec. The host galaxy is resolved and seen to be large, featureless, and red, with slightly displaced outer isophotes. The nucleus is unusually red. There is a rich cluster of galaxies in the field which is probably at a much higher redshift, and extended nebulosity from a nearby star. We discuss these results and the IR properties in terms of a mature merger of a luminous galaxy in which there is still a considerable amount of central dust and molecular clouds.