A catalog of habitable zone exoplanets January 18, 2017 Please Register or Log in to view the hidden image! A plot of the flux incident on an exoplanet (in units of the amount on Earth) versus the host star's temperature. The plot shows two ranges for the habitable zone, conservative green area) and optimistic (yellow area); it also shows where confirmed (blue dots) and unconfirmed (red circles) exoplanets lie in the plot. There are currently twenty known exoplanet candidates smaller than two Earth-radii that fall in their optimistically-defined habitable zones. Credit: Kane et al. 2016 The last two decades have seen an explosion of detections of exoplanets, as the sensitivity to smaller planets has dramatically improved thanks especially to the Kepler mission. These discoveries have found that the frequency of planets increases to smaller sizes: terrestrial planets are more common than gas giants. The significance of a universe rich in terrestrial sized planets naturally leads to the question about the "habitable zone (HZ)" – the region around a star where a suitable planet could sustain the conditions necessary for life. In this zone, the balance between stellar radiation onto the planet and radiative cooling from the planet allows water on the surface to be a liquid. (The definition also includes consideration of the planet's atmosphere and solid surface.) Read more at: https://phys.org/news/2017-01-habitable-zone-exoplanets.html#jCp
http://iopscience.iop.org/article/1...33A25BB232FB21C7BC3.c4.iopscience.cld.iop.org A CATALOG OF KEPLER HABITABLE ZONE EXOPLANET CANDIDATES Abstract The NASA Kepler mission ha s discovered thousands of new planetary candidates, many of which have been confirmed through follow-up observations. A primary goal of the mission is to determine the occurrence rate of terrestrial-size planets within the Habitable Zone (HZ) of their host stars. Here we provide a list of HZ exoplanet candidates from the Kepler Q1–Q17 Data Release 24 data-vetting process. This work was undertaken as part of the Kepler HZ Working Group. We use a variety of criteria regarding HZ boundaries and planetary sizes to produce complete lists of HZ candidates, including a catalog of 104 candidates within the optimistic HZ and 20 candidates with radii less than two Earth radii within the conservative HZ. We cross-match our HZ candidates with the stellar properties and confirmed planet properties from Data Release 25 to provide robust stellar parameters and candidate dispositions. We also include false-positive probabilities recently calculated by Morton et al. for each of the candidates within our catalogs to aid in their validation. Finally, we performed dynamical analysis simulations for multi-planet systems that contain candidates with radii less than two Earth radii as a step toward validation of those systems.
