Water Vapor and Clouds on the Habitable-zone Sub-Neptune Exoplanet K2-18b

@article{Benneke2019WaterVA,
  title={Water Vapor and Clouds on the Habitable-zone Sub-Neptune Exoplanet K2-18b},
  author={Bj{\"o}rn Benneke and Ian Wong and Caroline Piaulet and Heather A. Knutson and Joshua D. Lothringer and Caroline V. Morley and Ian J. M. Crossfield and Peter Gao and Thomas P. Greene and Courtney D. Dressing and Diana Dragomir and Andrew W. Howard and Peter R. McCullough and Eliza M.-R. Kempton and Jonathan J. Fortney and Jonathan D. Fraine},
  journal={The Astrophysical Journal Letters},
  year={2019},
  volume={887}
}
Results from the Kepler mission indicate that the occurrence rate of small planets (<3 R⊕) in the habitable zone of nearby low-mass stars may be as high as 80%. Despite this abundance, probing the conditions and atmospheric properties on any habitable-zone planet is extremely difficult and has remained elusive to date. Here, we report the detection of water vapor and the likely presence of liquid and icy water clouds in the atmosphere of the 2.6 R⊕ habitable-zone planet K2-18b. The simultaneous… 

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