The habitable epoch of the early Universe

  title={The habitable epoch of the early Universe},
  author={Abraham Loeb},
  journal={International Journal of Astrobiology},
  pages={337 - 339}
  • A. Loeb
  • Published 2014
  • Physics
  • International Journal of Astrobiology
Abstract In the redshift range 100≲(1+z)≲137, the cosmic microwave background (CMB) had a temperature of 273–373 K (0–100°C), allowing early rocky planets (if any existed) to have liquid water chemistry on their surface and be habitable, irrespective of their distance from a star. In the standard ΛCDM cosmology, the first star-forming halos within our Hubble volume started collapsing at these redshifts, allowing the chemistry of life to possibly begin when the Universe was merely 10–17 million… Expand
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