UGC 12591

UGC 12591 is a spiral galaxy located about 400 million light years away from the Earth in the constellation Pegasus. Also, it is the spiral galaxy with the highest known rotational speed of about 500 km/s, almost twice the rotational speed of our galaxy, the Milky Way. The high rotational speed means the galaxy must be very massive at the center; the galaxy has a mass estimated at 4 times that of the Milky Way,[1] making it the third most massive known spiral galaxy after ISOHDFS 27 and J2345-0449.

UGC 12591, taken by the Hubble Space Telescope

UGC 12591 is far from other galaxies; the nearest galaxy to it is 3.55 million light years away. However, it's shape shows that it probably had a merger or accretion event in its past. It looks somewhat lenticular-like, with a central bulge and dust lanes similar to the Sombrero Galaxy.[2]

References

  1. "A remarkable galactic hybrid". ESA/Hubble. Retrieved 16 April 2017.
  2. Ray, Shankar; Bagchi, Joydeep; Dhiwar, Suraj; Pandge, M. B.; Mirakhor, Mohammad; Walker, Stephen A.; Mukherjee, Dipanjan (2022). "Hubble Space Telescope Captures UGC 12591: Bulge/Disc properties, star formation and 'missing baryons' census in a very massive and fast-spinning hybrid galaxy". Monthly Notices of the Royal Astronomical Society. 517: 99–117. arXiv:2203.02885. Bibcode:2022MNRAS.517...99R. doi:10.1093/mnras/stac2683.