On 2011 February 1 the Kepler mission released data for 156,453 stars observed from the beginning of the science observations on 2009 May 2 through September 16. There are 1235 planetary candidates with transit-like signatures detected in this period. These are associated with 997 host stars. Distributions of the characteristics of the planetary candidates are separated into five class sizes: 68 candidates of approximately Earth-size (R p

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The empirical mass-luminosity relation at is presented for stars with masses 0.08È0.20 based M V M _ upon new observations made with Fine Guidance Sensor 3 on the Hubble Space T elescope. The targets are nearby, red dwarf multiple systems in which the magnitude di †erences are typically measured tô 0.1 mag or better. The values are generated using the best available parallaxes and are also accu-M V rate to^0.1 mag, because the errors in the magnitude di †erences are the dominant error source. In several cases this is the Ðrst time the observed sub-arcsecond multiples have been resolved at optical wavelengths. The mass-luminosity relation deÐned by these data reaches to and provides a M V \ 18.5 powerful empirical test for discriminating the lowest mass stars from high-mass brown dwarfs at wavelengths shorter than 1 km.

We present Hα-derived star-formation rates (SFRs) for three z ≃ 0.75 galaxy clusters. Our 1σ flux limit corresponds to a star-formation rate of 0.10-0.24 h −2 100 M ⊙ yr −1 , and our minimum reliable Hα + [N II] rest-frame equivalent width is 10Å. We show that Hα narrowband imaging is an efficient method for measuring star formation in distant clusters. In two out of three clusters, we find that the fraction of star-forming galaxies increases with projected distance from the cluster center. We also find that the fraction of star-forming galaxies decreases with increasing local galaxy surface density in the same two clusters. We compare the median rate of star formation among star-forming cluster galaxies to a small sample of star-forming field galaxies from the literature and find that the median cluster SFRs are ∼ 50% less than the median field SFR. We characterize cluster evolution in terms of the mass-normalized integrated cluster SFR and find that the z ≃ 0.75 clusters have more SFR per cluster mass on average than the z ≤ 0.4 clusters from the literature. The interpretation of this result is complicated by the dependence of the mass-normalized SFR on cluster mass and the lack of sufficient overlap in the mass ranges covered by the low and high redshift samples. We find that the fraction and luminosities of the brightest starburst galaxies at z ≃ 0.75 are consistent with their being progenitors of the post-starburst galaxies at z ≃ 0.45 if the post-starburst phase lasts several (∼ 5) times longer than the starburst phase.