The nature of the TRAPPIST-1 exoplanets.

  title={The nature of the TRAPPIST-1 exoplanets.},
  author={Simon L. Grimm and B-O. Demory and Micha{\"e}l Gillon and Caroline Dorn and Eric Agol and Artem Burdanov and Laetitia Delrez and Marko Sestovic and Amaury H. M. J. Triaud and Martin Turbet and 'Emeline Bolmont and Anthony Caldas and Julien de Wit and Emmanuel Jehin and J{\'e}r{\'e}my Leconte and Sean N. Raymond and Val{\'e}rie Van Grootel and Adam J. Burgasser and Sean Carey and Daniel C. Fabrycky and Kevin Heng and David M. Hernandez and James G. Ingalls and Susan M. Lederer and Franck Selsis and Didier Queloz},
  journal={arXiv: Earth and Planetary Astrophysics},
Context. The TRAPPIST-1 system hosts seven Earth-sized, temperate exoplanets orbiting an ultra-cool dwarf star. As such, it represents a remarkable setting to study the formation and evolution of terrestrial planets that formed in the same protoplanetary disk. While the sizes of the TRAPPIST-1 planets are all known to better than 5% precision, their densities have significant uncertainties (between 28% and 95%) because of poor constraints on the planet's masses. Aims.The goal of this paper is… 
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Tidal heating and the habitability of the TRAPPIST-1 exoplanets
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The ultracool dwarf star TRAPPIST-1 hosts seven Earth-size transiting planets, some of which could harbor liquid water on their surfaces. Ultraviolet observations are essential to measuring their
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