The Role of Meteorite Impacts in the Origin of Life

Abstract

The conditions, timing, and setting for the origin of life on Earth and whether life exists elsewhere in our solar system and beyond represent some of the most fundamental scientific questions of our time. Although the bombardment of planets and satellites by asteroids and comets has long been viewed as a destructive process that would have presented a barrier to the emergence of life and frustrated or extinguished life, we provide a comprehensive synthesis of data and observations on the beneficial role of impacts in a wide range of prebiotic and biological processes. In the context of previously proposed environments for the origin of life on Earth, we discuss how meteorite impacts can generate both subaerial and submarine hydrothermal vents, abundant hydrothermalsedimentary settings, and impact analogues for volcanic pumice rafts and splash pools. Impact events can also deliver and/or generate many of the necessary chemical ingredients for life and catalytic substrates such as clays as well. The role that impact cratering plays in fracturing planetary crusts and its effects on deep subsurface habitats for life are also discussed. In summary, we propose that meteorite impact events are a fundamental geobiological process in planetary evolution that played an important role in the origin of life on Earth. We conclude with the recommendation that impact craters should be considered prime sites in the search for evidence of past life on Mars. Furthermore, unlike other geological processes such as volcanism or plate tectonics, impact cratering is ubiquitous on planetary bodies throughout the Universe and is independent of size, composition, and distance from the host star. Impact events thus provide a mechanism with the potential to generate habitable planets, moons, and asteroids throughout the Solar System and beyond.

Macrobiont: Cradle for the Origin of Life and Creation of a Biosphere

“…of formations of craters on Earth sufficiently hot that they could be filled with water by melting of permafrost ice, or by subsequent meteorological precipitation over the available watershed. Such crater lakes would have provided both subaerial and buried hydrothermal regimes for durations that would depend on the energetics of the impactor (size and velocity) but could continue for 10 3 to 10 6 years for impacts producing crater diameters of ~5 to 200 km [ 145 ] as the thermal energy and/or water supply slowly dissipated.…”

“…These crater lakes have been championed as candidates for the OoL by a number of researchers because of their favorable properties and inevitable past existence, e.g., [ 145 , 146 ]. Only for the larger craters, of course, would the amount and burial depth of heat deposited have been sufficient to create a long-lived, high temperature system.…”

Shaping of the Present-Day Deep Biosphere at Chicxulub by the Impact Catastrophe That Ended the Cretaceous

“…In near-surface environments, asteroid impacts have been shown to increase the porosity and permeability of rocks, enhancing microbial colonization ( Cockell et al, 2002 , 2005 ; Pontefract et al, 2014 ; Osinski et al, 2020a ). In contrast, sedimentary rocks which often already contain microbially accessible porosity ( Friedmann, 1982 ), may have their porosity reduced by impact, resulting in a loss of colonization space ( Cockell and Osinski, 2007 ).…”

Exploring the environments of Martian impact‐generated hydrothermal systems and their potential to support life

“…Biosignatures, such as biofilms and fossilized microbes, have also been detected within extinct, impact-generated hydrothermal systems (Glamoclija et al 2007;Hode et al 2009;Ivarsson et al 2013), which indicates such terrestrial environments were habitable. Similar environments on Mars may also have had the potential to host life or even played a critical role in the origin of life; abiotic organic molecules may have been delivered to the Martian surface by impactors or synthesized within the hydrothermal environment (for an in-depth review, see Osinski et al 2020).…”