NGC 747


NGC 747 is a spiral galaxy located in the constellation Cetus. Its speed relative to the cosmic microwave background is 5,100 ± 19 km/s, which corresponds to a Hubble distance of 75.2 ± 5.3 Mpc. NGC 747 was discovered by American astronomer Francis Leavenworth in 1886. The luminosity class of NGC 747 is II and it has a broad HI line. To date, four non-redshift measurements yield a distance of 83.900 ± 4.166 Mpc, which is within the Hubble distance range. Note, however, that it is with the average value of independent measurements, when they exist, that the NASA/IPAC database calculates the diameter of a galaxy and that consequently the diameter of NGC 747 could be approximately 23.9 kpc. In the same area of the sky there are, among other things: the galaxies NGC 713, NGC 731, NGC 755 and NGC 767.