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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We present the results of a survey of 45 young (P250 Myr), close (P50 pc) stars with the Simultaneous Differential Imager (SDI) implemented at the VLT and the MMT for the direct detection of extrasolar planets. As part of the survey, we observed 54 objects, consisting of 45 close, young stars; two more distant (<150 pc), extremely young (10 Myr) stars; three stars with known radial velocity planets; and four older, very nearby (20 pc) solar analogs. Our SDI devices use a double Wollaston prism and a quad filter to take images simultaneously at three wavelengths surrounding the 1.62 m methane absorption bandhead found in the spectrum of cool brown dwarfs and gas giant planets. By differencing adaptive opticsYcorrected images in these filters, speckle noise from the primary star is significantly attenuated, resulting in photon (and flat-field)YnoiseYlimited data. In our VLT data, we achieved H-band contrasts k10 mag (5) at a separation of 0.5 00 from the primary star on 45% of our targets and H-band contrasts k 9 mag at a separation of 0.5 00 on 80% of our targets. With these contrasts, we can image (5 detection) a 7 M J planet 15 AU from a 70 Myr K1 star at 15 pc or a 7.8 M J planet at 2 AU from a 12 Myr M star at 10 pc. We detected no candidates with S/N > 2 which behaved consistently like a real object. From our survey null result, we can rule out (with 93% confidence) a model planet population where N (a) / constant out to a distance of 45 AU.

M17 is one of the youngest and most massive nearby star-formation regions in the Galaxy. It features a bright H II region erupting as a blister from the side of a giant molecular cloud (GMC). Combining photometry from the Spitzer Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE) with complementary infrared (IR) surveys, we identify candidate young stellar objects (YSOs) throughout a 1.5 • × 1 • field that includes the M17 complex. The long sightline through the Galaxy behind M17 creates significant contamination in our YSO sample from unassociated sources with similar IR colors. Removing contaminants, we produce a highly-reliable catalog of 96 candidate YSOs with a high probability of association with the M17 complex. We fit model spectral energy distributions to these sources and constrain their physical properties. Extrapolating the mass function of 62 intermediate-mass YSOs (M ⋆ > 3 M ⊙ ), we estimate that >1000 stars are in the process of forming in the extended outer regions of M17. The remaining 34 candidate YSOs are found in a 0.17 deg 2 field containing the well-studied M17 H II region and photodissociation region, where bright diffuse mid-IR emission drastically reduces the sensitivity of the GLIMPSE point-source detections.By inspecting IR survey images from IRAS and GLIMPSE, we find that M17 lies on the rim of a large shell structure ∼0.5 • in diameter (∼20 pc at 2.1 kpc). We present maps of 12 CO and 13 CO (J = 2 → 1) emission observed with the Heinrich Hertz Telescope. The CO emission shows that the shell is a coherent, kinematic structure associated with M17, centered at v = 19 km s −1 . The shell is an extended bubble outlining the photodissociation region of a faint, diffuse H II region several Myr old. We identify a group of candidate ionizing stars within the bubble. YSOs in our catalog are concentrated around the bubble rim, providing evidence that massive star formation has been triggered by the expansion of the bubble. The formation of the massive cluster ionizing the M17 H II region itself may have been similarly triggered. We conclude that the star formation history in the extended environment of M17 has been punctuated by successive waves of massive star formation propagating through a GMC complex.

We present a comparison of CO fundamental rovibrational lines (observed in the M band near 4.7 lm) from the inner circumstellar disks around the Herbig AeBe stars AB Aur and HD 141569. The CO spatial profiles and temperatures constrain the location of the gas for both stars to a distance of less than 50 AU. The CO emission from the disk of the $4 Myr star AB Aur shows at least two temperature components, the inner disk at a rotational temperature of 1540 AE 80 K and the outer disk at 70 AE 10 K. The hot gas is located near the hot bright inner rim of the disk and the cold gas is located in the outer disk from 8-50 AU. The relative intensities of low-J lines suggest that the cold gas is optically thick. The excitation of CO in both temperature regimes is dominated by infrared fluorescence (resonant scattering). In the more evolved disk around HD 141569, the CO is excited by UV fluorescence. The relative intensity of the CO emission lines implies a rotational temperature of 190 AE 30 K. The resulting column density is $10 11 cm À2 , indicating approximately 10 19 g of CO. The observed line profiles indicate that the inner disk has been cleared of CO gas by stellar radiation out to a minimum of 17 AU. The residual mass of CO suggests that the inner disk of HD 141569 is not in an active phase of planet building but it does not rule out the possibility that giant planet building has previously occurred.