2009ApJ...705L.158K

We present spectroscopic confirmation of the "Pisces Overdensity," also known as "Structure J," a photometric overdensity of RR Lyrae stars discovered by the Sloan Digital Sky Survey at an estimated photometric distance of ∼85 kpc. We measure radial velocities for eight RR Lyrae stars within Pisces. We find that five of the eight stars have heliocentric radial velocities within a narrow range of -87 km/s < v_r< -67 km/s, suggesting that the photometric overdensity is mainly due to a physically associated system, probably a dwarf galaxy or a disrupted galaxy. Two of the remaining three stars differ from one another by only 9 km/s, but it would be premature to identify them as a second system.