eEarth Discussions www.electronic-earth-discuss.net 1815-3836 1815-3844 2 2 2007 10.5194/eed-2-99-2007 http://www.electronic-earth-discuss.net/2/99/2007/ http://www.electronic-earth-discuss.net/2/99/2007/eed-2-99-2007.html http://www.electronic-earth-discuss.net/2/99/2007/eed-2-99-2007.pdf 99 113 2007-07-10 Noble gas signature of the late heavy bombardment in the Earth's atmosphere B. Marty bmarty@crpg.cnrs-nancy.fr A. Meibom Centre de Recherches Pétrographiques et Géochimiques and Ecole Nationale Supérieure de Géologie, Nancy Universités, Nancy, France Muséum National d'Histoire Naturelle, Paris, France The Lunar cratering record is consistent with the occurrence of a late heavy bombardment (LHB), which marked the end of terrestrial planet accretion 3.8 billion years ago. However, clear evidence of a LHB on Earth has not yet been identified. Here it is shown that the LHB did indeed occur on Earth and that we are breathing its aftermaths. 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