C70

C70 (or NGC 300) is a loose spiral galaxy in the constellation of Sculptor, lying near that constellation's southern border where it approaches neighbouring Phoenix. With an apparent diameter of nearly twenty arcminutes, if C70 could be seen with the naked eye, it would cover an area of sky approaching that of the Moon's disc. With a visual magnitude of +7.9, however, the galaxy cannot be seen without telescopic aid.

As viewed from Earth, C70 is so angled that its diffuse spiral structure is clearly visible. Two broad arms spiral out from the west and east to extend around the galaxy's rim, and several smaller, less defined arms are also present between these two. The galaxy's nucleus is comparatively small in comparison with its disc, but an intense source of X-rays that are thought to be generated by two black holes rotating rapidly around a common centre of gravity.

The distance of this galaxy from the Milky Way is estimated at some six to seven million light years. C70 occupies the same field as the Sculptor Group of galaxies, and was historically thought to be a member of this group. More recent calculations, however, have shown that C70 is independent of this more distant group of galaxies, though it lies on the same line of sight as seen from Earth.