Page "NGC 891" Paragraph 9

The galaxy is a member of a small group of galaxies, sometimes called the NGC 1023 Group.

Other galaxies in this group are the NGCs 925, 949, 959, 1003, 1023, and 1058, and the UGCs 1807, 1865 ( DDO 19 ), 2014 ( DDO 22 ), 2023 ( DDO 25 ), 2034 ( DDO 24 ), and 2259.

The outskirts with low surface brightness are populated by multiple, coherent, and vast substructures, like giant streams that loop around the parent galaxy up to distances of approximately 50 kpc.

The bulge and the disk are surrounded by a flat and thick cocoon-like stellar structure.

These have vertical and radial distances of up to 15 kpc and 40 kpc, respectively.

NGC 891 ( North part ) close up by Hubble Space Telescope | HST, 3. 24 ′ view.

Credit: NASA / STScI / WikiSky