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Physics, Astronomy & Cosmology / How is the habitable zone defined for the Trappist-1 system?
« on: 23/02/2017 04:18:03 »
Today NASA announced that there are 7 planets with similar masses to that of the Earth, all orbiting the tiny star TRAPPIST-1. In the press release they said that 3 of the planets are within the Goldilocks zone where liquid water would be found, based on the energy output of the star. But they also said that the planets are likely tidally locked to the the star (longest orbit period is shorter than 1 Earth month), which means that the light and dark sides of each of the planets are likely to have dramatically different climates. And just to complicate matters, the planets' orbits are so close to one another that the gravitational interaction between the planets significantly alters the orbital periods. This would indicate to me that there could be significant tidal forces leading to increased geothermal energy (this could potentially also disrupt tidal locking with the star...)