We present results from spectroscopic observations with the Michigan/Magellan Fiber System (M2FS) of 182 stellar targets along the line of sight (LOS) to the newly discovered "ultrafaint" object Reticulum 2 (Ret 2). For 37 of these targets, the spectra are sufficient to provide simultaneous estimates of LOS velocity ({nu}i_los_, median random error {delta}{nu}los=1.4km/s), effective temperature (T_eff_, {delta}Tef=478K), surface gravity (logg, {delta}logg=0.63dex), and iron abundance ([Fe/H], {delta}[Fe/H]=0.47dex). We use these results to confirm 17 stars as members of Ret 2. From the member sample we estimate a velocity dispersion of {sigma}{nu}los=3.6_-0.7_^+1.0^km/s about a mean of =64.3_1.2_^+1.2^km/s in the solar rest frame (~-90.9km/s in the Galactic rest frame), and a metallicity dispersion of {sigma}[Fe/H]=0.49_-0.14_^+0.19^dex about a mean of =-2.58_-0.33_^+0.34^. These estimates marginalize over possible velocity and metallicity gradients, which are consistent with zero. Our results place Ret 2 on chemodynamical scaling relations followed by the Milky Way's dwarf-galactic satellites. Under assumptions of dynamic equilibrium and negligible contamination from binary stars --both of which must be checked with deeper imaging and repeat spectroscopic observations-- the estimated velocity dispersion suggests a dynamical mass of M(R_h_)~5R_h_{sigma}{nu}los^2^/(2G)=2.4_-0.8_^+1.4^x10^5^M_{sun} enclosed within projected halflight radius R_h~32pc, with mass-to-light ratio ~2M(R_h_)/L_V_=467_-168_^+286^ in solar units.

Cone search capability for table J/ApJ/808/108/table1 (M2FS stellar spectroscopy of Reticulum 2)