Kepler-22b: A 2.4 Earth-radius Planet in the Habitable Zone of a Sun-like Star

A search of the time-series photometry from NASA's Kepler spacecraft reveals a transiting planet candidate orbiting the 11th magnitude G5 dwarf KIC 10593626 with a period of 290 days. The characteristics of the host star are well constrained by high-resolution spectroscopy combined with an asteroseismic analysis of the Kepler photometry, leading to an estimated mass and radius of 0.970 +/- 0.060 MSun and 0.979 +/- 0.020 RSun. The depth of 492 +/- 10ppm for the three observed transits yields a radius of 2.38 +/- 0.13 REarth for the planet. The system passes a battery of tests for false positives, including reconnaissance spectroscopy, high-resolution imaging, and centroid motion. A full BLENDER analysis provides further validation of the planet interpretation by showing that contamination of the target by an eclipsing system would rarely mimic the observed shape of the transits. The final validation of the planet is provided by 16 radial velocities obtained with HIRES on Keck 1 over a one year span. Although the velocities do not lead to a reliable orbit and mass determination, they are able to constrain the mass to a 3{\sigma} upper limit of 124 MEarth, safely in the regime of planetary masses, thus earning the designation Kepler-22b. The radiative equilibrium temperature is 262K for a planet in Kepler-22b's orbit. Although there is no evidence that Kepler-22b is a rocky planet, it is the first confirmed planet with a measured radius to orbit in the Habitable Zone of any star other than the Sun.Comment: Accepted to Ap

Na+-dependent Ca2+ uptake in isolated opercular epithelium of Fundulus heteroclitus

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Stress analysis of cylindrical pressure vessels with closely spaced nozzles by the finite-element method. Volume 1. Stress analysis of vessels with two closely spaced nozzles under internal pressure. [BWR; PWR; MULT-NOZZLE code]

A finite-element computer program, MULT-NOZZLE, was developed for the stress analysis of cylindrical pressure vessels with two or three closely spaced reinforced nozzles. MULT-NOZZLE consists of two modules which may be operated independently. The first module, FEMG, automatically prepares a finite-element mesh including the nodal point coordinates, finite-element connectivities, mesh options, and boundary value specifications for input to the finite-element solution module SAP3M. SAP3M, which is a modified and improved version of the SAP3 computer program, computes the nodal point displacements and stress tensor components, and prints and/or stores the results for later postprocessing. The accuracy of the SAP3M module is demonstrated by comparison studies of two classical theory-of-elasticity problems: a simply supported beam and a thick-walled ring under internal pressure loading. A complete discussion of MULT-NOZZLE is presented in four volumes. Volume develops the finite-element idealization for pressure vessels with two idential radially attached closely spaced nozzles for internal pressure loading. The nozzles may be unreinforced or fully reinforced according to the rules of the ASME Boiler and Pressure Vessel Code and may be located in either a longitudinal or a transverse plane of the vessel. Validation of the program for analyzing this type of structure is demonstrated by the analysis of three two-nozzle pressure vessel models and comparison of results with experimental data. In general, quite satisfactory results were obtained