Cometary micrometeorites and input of prebiotic compounds

• Published in: BIO Web of Conferences
• Main Author: Engrand, C.
• Other Authors: Centre de Sciences Nucléaires et de Sciences de la Matière (CSNSM), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
• Format: Conference Object
• Language: English
• Published: HAL CCSD 2014
• Subjects: Ultracarbonaceous Antartic micrometeorites; interplanetary dust particles; carbonaceous chondrites; Isotopic compositions; Cosmic spherules; Amino-acids; Fossil micrometeorites; Solar-system; 433 eros; oxygen; [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]; Antarctic; Eros; Antarc*; antartic*
• Online Access: https://hal.in2p3.fr/in2p3-01078768; https://doi.org/10.1051/bioconf/20140203003

International audience The apparition of life on the early Earth was probably favored by inputs of extraterrestrial matter brought by carbonaceous chondrite-like objects or cometary material. Interplanetary dust collected nowadays on Earth is related to carbonaceous chondrites and to cometary material. They contain in particular at least a few percent of organic matter, organic compounds (amino-acids, PAHs,.), hydrous silicates, and could have largely contributed to the budget of prebiotic matter on Earth, about 4 Ga ago. A new population of cometary dust was recently discovered in the Concordia Antarctic micrometeorite collection. These "Ultracarbonaceous Antarctic Micrometeorites" (UCAMMs) are dominated by deuterium-rich and nitrogen-rich organic matter. They seem related to the "CHON" grains identified in the comet Halley in 1986. Although rare in the micrometeorites flux (<5% of the micrometeorites), UCAMMs could have significantly contributed to the input of prebiotic matter. Their content in soluble organic matter is currently under study.