Pisces Overdensity

Not to be confused with Pisces Dwarf.

The Pisces Overdensity is a clump of stars in the Milky Way's halo, which may be a disrupted dwarf spheroidal galaxy.^[5] 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.^[2] 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.^[4]

Pisces Overdensity
Observation data (J2000 epoch)
Constellation	Pisces
Right ascension	23h 19m 00s[1]
Declination	+00° 00′ 00″[1]
Distance	260 kly (80 kpc)[2]
Absolute magnitude (V)	−10.35[3]
Characteristics
Type	dIrr/dSph[3]
Apparent size (V)	~1°[4]
Other designations
Pisces Plume[1]

The Pisces Overdensity is one of the faintest satellites of the Milky Way.^[5] Its mass is estimated to be at least 10⁵ Solar masses.^[2] 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.^[4] The Pisces Overdensity is located near the plane, where the Magellanic Clouds lie. There may exist a connection between the Magellanic Stream and this galaxy.^[2]