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

Rationality and the Shoulds

This paper is about rational and irrational uses of deontological words, such as "should", "ought", and "must", referred to as "the shoulds". Rationality is taken as a mutual relationship between conceptual schemes and human agency. These are expressed in what Bakhtin referred to as authoritative discourse and internally persuasive discourse respectively. When the conceptual scheme is in place and its authority transparent, and there is interplay between authoritative discourse and internally persuasive discourse, then the shoulds are perceived as rational. When the interplay is disrupted or suppressed the shoulds are seen as irrational. Breakdown occurs in two main ways. First, when the effective conceptual schemes are hidden, and the origin of the shoulds obscured. We describe some instances of the latter, from philosophy, psychotherapy, and experimental studies of rationality. Second, in technology and science the mutual relationship sometimes breaks down because authoritative discourse is too powerful, and inhibits the interplay in order to maintain itself. After describing these pathologies, we turn to William James, who drew attention to a repair kit for rationality in his detection of the psychologist's fallacy. Describing the work of Dewey and Husserl as elaborations of this, we distinguished two essential aspects of rationality, disciplinary expressed in authoritative discourse, and emancipatory expressed in internally persuasive discourse

A new random permutation test in ANOVA models

Analysis of variance, Random permutation tests, Simulation,