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We present Keck/DEIMOS spectroscopy of stars in the recently discovered MilkyWay satellites Hydra II, Pisces II, and Laevens 1. We measured a velocitydispersion of 5.4 (+3.6 -2.4) km/s for Pisces II, but we did not resolve thevelocity dispersions of Hydra II or Laevens 1. We marginally resolved themetallicity dispersions of Hydra II and Pisces II but not Laevens 1.Furthermore, Hydra II and Pisces II obey the luminosity-metallicity relationfor Milky Way dwarf galaxies (<[Fe/H]> = -2.02 +/- 0.08 and -2.45 +/- 0.07,respectively), whereas Laevens 1 does not (<[Fe/H]> = -1.68 +/- 0.05). Thekinematic and chemical properties suggest that Hydra II and Pisces II are dwarfgalaxies, and Laevens 1 is a globular cluster. We determined that two of thepreviously observed blue stars near the center of Laevens 1 are not members ofthe cluster. A third blue star has ambiguous membership. Hydra II has a radialvelocity <v_helio> = 303.1 +/- 1.4 km/s, similar to the leading arm of theMagellanic stream. The mass-to-light ratio for Pisces II is 370 (+310 -240)M_sun/L_sun. It is not among the most dark matter-dominated dwarf galaxies, butit is still worthy of inclusion in the search for gamma rays from dark matterself-annihilation.

Spectroscopic Confirmation of the Dwarf Galaxies Hydra II and Pisces II and the Globular Cluster Laevens 1