Mice Galaxies

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NGC 4676A / 4676B

The Mice Galaxies, NGC 4676A (right)/NGC 4676B (left)
Observation data (J2000 epoch)
Constellation Coma Berenices
Right ascension 12h 46m 10.1s / 12h 46m 11.2s[1]
Declination +30° 43′ 55″ / +30° 43′ 22″[1]
Redshift 6613 ± 8 / 6607 ± 7 km/s[1]
Distance 290 Mly[2]
Type Irr / SB(s)0/a pec[1]
Apparent dimensions (V) 2′.3 × 0′.7 / 2′.2 × 0′.8[1]
Apparent magnitude (V) 14.7 / 14.4[1]
Notable features Interacting galaxies
Other designations
Mice Galaxies,[1] IC 819 / 820,[1] UGC 7938 / 7939,[1]
PGC 43062 / 43065,[1] Arp 242[1]
See also: Galaxy, List of galaxies

NGC 4676, or the Mice Galaxies, are two spiral galaxies in the constellation Coma Berenices. About 290 million light-years away[2], they are presently in the process of colliding and merging. Their name refers to the long tails produced by tidal action — the relative difference between gravitational pulls on the near and far parts of each galaxy — known here as a galactic tide. Members of the Coma cluster, it is a possibility that both galaxies have experienced collision, and will continue colliding until they coalesce. The colors of the galaxy are peculiar. In the upper galaxy, a core with some dark markings is surrounded by a bluish white remnant of spiral arms. The tail is unusual, starting out blue and terminating in a more yellowish color, despite the fact that the beginning of each arm in virtually every spiral galaxy starts yellow and terminates in a bluish color. The lower galaxy is closer to normal, with a yellowish core and two arcs; arm remnants underneath are bluish as well.

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  1. ^ a b c d e f g h i j k NASA/IPAC Extragalactic Database. Results for NGC 4676A / 4676B. Retrieved on 2006-11-21.
  2. ^ a b Chien, Li-Hsin; Barnes, Joshua E., Kewley, Lisa J., Chambers, Kenneth, C. (2007). "Multiobject Spectroscopy of Young Star Clusters in NGC 4676". ApJL 660: 105–108. doi:10.1086/518215.