Pisces I (dwarf galaxy)
|Pisces I Dwarf Galaxy|
|Observation data (J2000 epoch)|
|Right ascension||~23h 40m 00s|
|Distance||260 kly (80 kpc)|
|Apparent size (V)||~1°|
|Pisces I, Psc I, PGC 3792, LEDA 3792|
Pisces I (Psc I) or Pisces Overdensity is a clump of stars in the Milky Way's halo, which may be a disrupted dwarf spheroidal galaxy. It is situated in the Pisces constellation and was discovered in 2009 by analysis of distribution of RR Lyrae stars in the data obtained by the Sloan Digital Sky Survey's data. The galaxy is located at the distance of about 80 kpc from the Sun and moves towards it with a speed of about 75 km/s.
Pisces I is one of the faintest satellites of the Milky Way. Its mass is estimated to be at least 105 Solar masses. However it has a large size of about several degrees (around 1 kpc) and may be in a transitional phase between a gravitationally bound galaxy and completely unbound system. Pisces I is located near the plane, where the Magellanic Clouds lie. There may exist a connection between the Magellanic stream and this galaxy.
- Belokurov, V.; et al. (2010), "Big fish, small fish: Two New Ultra-Faint Satellites of the Milky Way", The Astrophysical Journal Letters, 712: L103–106, Bibcode:2010ApJ...712L.103B, arXiv: , doi:10.1088/2041-8205/712/1/L103.
- Kollmeier, Juna A.; et al. (2009), "Spectroscopic Confirmation of the Pisces Overdensity", The Astrophysical Journal Letters, 705 (2): L158–L162, Bibcode:2009ApJ...705L.158K, arXiv: , doi:10.1088/0004-637X/705/2/L158.
- Watkins, L. L.; et al. (2009), "Substructure revealed by RR Lyraes in SDSS Stripe 82", Monthly Notices of the Royal Astronomical Society, 398 (4): 1757–70, Bibcode:2009MNRAS.398.1757W, arXiv: , doi:10.1111/j.1365-2966.2009.15242.x.
- "NAME Pisces I -- Galaxy". SIMBAD.
- "Object No. 1 - Pisces I". NASA/IPAC Extragalactic Database.