The Binary Galaxies NGC 147 and NGC 185

Contrary to a previously published claim, it is found that the spheroidal galaxies NGC 147 and NGC 185 probably form a stable binary system. Distance estimates place this pair on the near side of the Andromeda subgroup of the Local Group. The fact that this system has probably remained stable over a Hubble time suggests that it does not have a plunging orbit that brings it very close to M31. It is noted that the only two Local Group galaxy pairs in which the components have comparable masses also have similar morphological types. NGC 147 and NGC 185 are both spheroidal galaxies, while the LMC and SMC are both irregular galaxies. This suggests that protogalaxies of similar mass, that are spawned in similar environments, evolve into objects having similar morphologies.