Description:

To be habitable, a world (planet or moon) does not need to be located in the stellar habitable zone (HZ), and worlds in the HZ are not necessarily habitable. Here, we illustrate how tidal heating can render terrestrial or icy worlds habitable beyond the stellar HZ. Scientists have developed a language that neglects the possible existence of worlds that offer more benign environments to life than Earth does. We call these objects "superhabitable" and discuss in which contexts this term could be used, that is to say, which worlds tend to be more habitable than Earth. In an appendix, we show why the principle of mediocracy cannot be used to logically explain why Earth should be a particularly habitable planet or why other inhabited worlds should be Earth-like. Superhabitable worlds must be considered for future follow-up observations of signs of extraterrestrial life. Considering a range of physical effects, we conclude that they will tend to be slightly older and more massive than Earth and that their host stars will likely be K dwarfs. This makes Alpha Centauri B, member of the closest stellar system to the Sun that is supposed to host an Earth-mass planet, an ideal target for searches of a superhabitable world. __ René Heller (1), John Armstrong (2) ((1) McMaster University, Dept. of Physics & Astronomy, Hamilton (ON), Canada, (2) Weber State University, Dept. of Physics, Ogden (UT), USA) __ Published in Astrobiology (Jan. 2014), http://arxiv.org/abs/1401.2392?context=astro-ph.EP http://online.liebertpub.com/doi/full/10.1089/ast.2013.1088 __ This upload contains a variety of copyright material. The intellectual property of individuals (as named) remain theirs. No copyright is claimed from Superhabitable Worlds. I assert that uploading this on Scribd is permissible under fair use principles in U.S. copyright laws. If one believes this material has been used in an unauthorized manner, please contact me. __ Reason for upload: Academic