UGC 8005, Arp 159, CGCG 129-028, MCG +04-30-023, PGC 43586[1]
NGC 4747 is a barred spiral galaxy located in the constellation Coma Berenices. It is located at a distance of about 35 million light years from Earth, which, given its apparent dimensions, means that NGC 4747 is about 35,000 light years across.[1] It was discovered by William Herschel on April 6, 1785.[2] It is included in the Atlas of Peculiar Galaxies in the interior absorption category.
The galaxy is a member of the Coma I Group, which is part of the Local Supercluster.[3] NGC 4747 is interacting with neighboring spiral galaxy NGC 4725, with its spiral arms showing indications of warping. The pair have an angular separation of 24′, which corresponds to a projected linear separation of 370 kly.[4] A close approach between NGC 4747 and the more massive NGC 4725 that took place 320 million years before observed created tidal plumes in NGC 4747.[5]
A short tidal plume extends from NGC 4747 toward NGC 4725, to the south-west, and one more pronounced towards the north-east,[6] with a length of 8 arcminutes. The optical north-east plume has also a hydrogen counterpart, which is offset by 50 degrees from the visual counterpart.[4] Two knots, possibly star clusters, are visible in the northeast plume, that could become tidal dwarf galaxies, as they appear to be massive enough to be self-gravitating.[7][8]
The star formation rate of the galaxy is estimated to be 0.13 solar masses per year.[9]
^ abWevers, B. M. H. R.; et al. (November 1984). "Neutral hydrogen observations of the interacting galaxies NGC 4725 and NGC 4747". Astronomy and Astrophysics. 140: 125–140. Bibcode:1984A&A...140..125W.
^Mullan, B.; Kepley, A. A.; Maybhate, A.; English, J.; Knierman, K.; Hibbard, J. E.; Bastian, N.; Charlton, J. C.; Durrell, P. R.; Gronwall, C.; Elmegreen, D.; Konstantopoulos, I. S. (26 April 2013). "Under Pressure: Star Clusters and the Neutral Hydrogen Medium of Tidal Tails". The Astrophysical Journal. 768 (2): 194. arXiv:1304.3414. Bibcode:2013ApJ...768..194M. doi:10.1088/0004-637X/768/2/194.