NGC 7317
NGC 7317 is an elliptical galaxy that is a member of Stephan's Quintet in the constellation Pegasus. Its velocity with respect to the cosmic microwave background is 6272 ± 35 km/s, which corresponds to a Hubble distance of 301.7 ± 21.2 Mly (92.51 ± 6.51 Mpc).[1] In addition, four non-redshift measurements gives a distance of 294.27 ± 34.22 Mly (90.225 ± 10.491 Mpc).[2] It was discovered on 27 September 1873 by French astronomer Édouard Stephan.[3] The SIMBAD database lists NGC 7317 as 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.[4] The James Webb Space Telescope photographed it as part of Stephan's Quintet; the image was released on 12 July 2022. See alsoReferences
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