490 light years away lies Kepler-186f, a rocky world orbiting a red-dwarf star which is the first definitive Earth-sized planet found in the habitable zone around its parent star, the temperature at which water is at its liquid phase and organic life becomes a possibility. The announcement of the new Kepler team discovery was in a new report by Dr Elisa Quintana, Thomas Barclay (both interviewed in this video), Jason Rowe and others of the SETI Institute at Nasa's Ames Research Centre, whom you can see more of here www.youtube.com/watch?v=UogSOfkoib4 The Kepler exoplanet-hunting telescope run by the National Aeronautics and Space Administration discovered the new planet, one of five in orbit around the red dwarf star Kepler-186. All of the others 186(b-e) are closer to their red sun 186a and are outside the habitable zone Planet 186f has a radius that is 1.1 times the radius of Earth. About 70 per cent of all the galaxy's suns are red dwarfs, and these are weaker than our own star in terms of solar power output. Rocky planets bigger than Earth have more gravity and pull in lots of hydrogen and helium gases that turn them into gassy planets, like Neptune or Jupiter like planets which are common throughout the many solar systems observed across the galaxy. Smaller rocky planets acquire their atmospheres when gases such as carbon dioxide and water vapour are released by volcanoes. In the rare case when such a rocky planet is within the habitable zone, when water forms then it should remain liquid and would flow across the surface, mixing molecules and acting like the great solvent we know and love thereby giving organic chemistry a chance to thrive. Given the long life of red-dwarf stars, which burn their nuclear fuel much more slowly than larger stars such as our sun and the giant white and blue stars in our galaxy, gives habitable planets in these systems plenty of time to generate complex life if conditions allow it. However, even though this planet is in the habitable zone it may not be anything like habitable for humans or even very resilient earth life. Red dwarf stars are often vulnerable to frequent solar flares, without a strong magnetic field to deflect high energy charged particles, the planet would be constantly bombarded with high levels of particle radiation. This would damage some of the very fragile molecules of life, including DNA. Nevertheless for life to thrive it must evolve, to evolve it must mutate. Some mutations are generated by random high energy particle collisions from the solar wind and cosmic rays. Hence, having a sun prone to flares may help trigger evolution on such a world, perhaps starting it billions of years before its discovery and having let it develop into a myriad of forms.

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