Rare Earth: alien planets and life (Introduction)

by David Turell , Wednesday, July 20, 2016, 22:09 (3049 days ago) @ David Turell

The science writers are so hopeful that life is elsewhere that their wishful thinking poisons their reporting:-http://www.scientificamerican.com/article/2-newfound-alien-planets-may-be-capable-of-supporting-life/?WT.mc_id=SA_WR_20160720-"NASA's Kepler space telescope has spotted four possibly rocky alien planets orbiting the same star, and two of these newfound worlds might be capable of supporting life.-"The four exoplanets circle a red dwarf — a star smaller and dimmer than the sun—called K2-72, which lies 181 light-years from Earth in the Aquarius constellation. All four worlds are between 20 percent and 50 percent wider than Earth, making them good candidates to be rocky, discovery team members said.-"Two of the four planets, known as K2-72c and K2-72e, appear to be in the star's "habitable zone"—that just-right range of distances at which liquid water can exist on a world's surface, the scientists added. [How Habitable Zones for Exoplanets Work (Infographic)]-"Because K2-72 is a red dwarf, its habitable zone is much closer in than that of the sun. For example, K2-72c completes one orbit every 15 Earth days, yet it is likely just 10 percent warmer than our planet. K2-72e has a 24-Earth-day year, and it's about 6 percent colder than Earth, the scientists said. (All four newfound planets complete an orbit in 24 Earth days or less, making them closer to K2-72 than Mercury is to the sun.)"-Comment: Foolishness. It takes lots more than a rocky planet with the right temperature to have life. In this chain of articles many of the many requirements are listed. There are three whole books about the subject, two of which have been noted here.