We present stellar velocity dispersion profiles for seven Milky Way dwarf spheroidal (dSph)
satellite galaxies. We have measured 8394 line-of-sight velocities (�2.5 km s-1) for 6804
stars from high-resolution spectra obtained at the Magellan and MMT telescopes. We
combine these new data with previously published velocities to obtain the largest available
kinematic samples, which include more than 5500 dSph members. All the measured dSphs
have stellar velocity dispersion of order 10 km s-1 that remains approximately constant with�…

We report the discovery of TrES-4, a hot Jupiter that transits the star GSC 02620-00648
every 3.55 days. From high-resolution spectroscopy of the star, we estimate a stellar
effective temperature of T eff= 6100�150 K, and from high-precision z and B photometry of
the transit we constrain the ratio of the semimajor axis a and the stellar radius R* to be a/R*=
6.03�0.13. We compare these values to model stellar isochrones to constrain the stellar
mass to be M*= 1.22�0.17 M☉. Based on this estimate and the photometric time series, we�…