Do the TRAPPIST-1 Planets Have Hydrogen-rich Atmospheres?

  title={Do the TRAPPIST-1 Planets Have Hydrogen-rich Atmospheres?},
  author={Yasunori Hori and Masahiro Ogihara},
  journal={The Astrophysical Journal},
  • Y. Hori, M. Ogihara
  • Published 12 December 2019
  • Physics, Geology
  • The Astrophysical Journal
Recently, transmission spectroscopy in the atmospheres of the TRAPPIST-1 planets revealed flat and featureless absorption spectra, which rule out cloud-free hydrogen-dominated atmospheres. Earth-sized planets orbiting TRAPPIST-1 likely have either a clear or a cloudy/hazy hydrogen-poor atmosphere. In this paper, we investigate whether a proposed formation scenario is consistent with expected atmospheric compositions of the TRAPPIST-1 planets. We examine the amount of a hydrogen-rich gas that… 

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