NGC 5291

NGC 5291 is a system of interacting galaxies in the constellation Centaurus. Its velocity with respect to the cosmic microwave background is, which corresponds to a Hubble distance of. However, two non-redshift measurements give a closer mean distance of. It was discovered by British astronomer John Herschel on 8 May 1834.
NGC 5291 is surrounded by a collisional ring, containing a young and star-forming tidal dwarf galaxy, where dark matter has been detected. It is also a Seyfert II galaxy, i.e. it has a quasar-like nucleus with very high surface brightnesses whose spectra reveal strong, high-ionisation emission lines, but unlike quasars, the host galaxy is clearly detectable.