Endogenous production, exogenous delivery and impact-shock synthesis of organic molecules: an inventory for the origins of life

  title={Endogenous production, exogenous delivery and impact-shock synthesis of organic molecules: an inventory for the origins of life},
  author={Christopher F. Chyba and Carl E. Sagan},
Sources of organic molecules on the early Earth divide into three categories: delivery by extraterrestrial objects; organic synthesis driven by impact shocks; and organic synthesis by other energy sources (such as ultraviolet light or electrical discharges). Estimates of these sources for plausible end-member oxidation states of the early terrestrial atmosphere suggest that the heavy bombardment before 3.5 Gyr ago either produced or delivered quantities of organics comparable to those produced… 
The exogenous delivery of amino acids to the modern Earth: An evaluation from polar ices
Exogenous sources have been suggested as an alternative for the Earth-based synthesis of the organic compounds necessary for the origin of life (Chyba and Sagan, 1992). If extraterrestrial sources
Pre-biotic organic synthesis: laboratory simulation experiments and their significance for the origin of life in the solar system
  • M. Engel
  • Environmental Science
    Optical Engineering + Applications
  • 2011
It is commonly assumed that the origin of life on Earth and perhaps elsewhere in the solar system was preceded by the synthesis and accumulation of organic compounds essential for life as we know it
Comets as a source of prebiotic organic molecules for the early Earth.
Life on Earth originated during the final throes of the heavy bombardment, in which the Earth—Moon system, as well as the rest of the inner solar system, was subjected to an intense bombardment of
One-Pot Hydrogen Cyanide-Based Prebiotic Synthesis of Canonical Nucleobases and Glycine Initiated by High-Velocity Impacts on Early Earth.
The experimental results show that one-pot impact-plasma-initiated synthesis of all the RNA canonical nucleobases and the simplest amino acid glycine is possible in this type of atmosphere in the presence of montmorillonite.
Proof of exogenous delivery of organics to the early Earth in the sudbury impact structure
  • L. Becker, J. Bada
  • Geology, Physics
    Origins of life and evolution of the biosphere
  • 2006
Fullerenes (C60 and C70 ) have recently been identified in a shock-produced breccia (Onaping Formation) associated with the 1.85 billion-year-old Sudbury Impact Structure (Becker et. al., 1994). The
Caveats to Exogenous Organic Delivery from Ablation, Dilution, and Thermal Degradation
This study tests how the transfer of organic matter to the surface of Earth is affected by energy-dissipation processes such as ablation and airbursts by looking at various properties of meteors and atmospheric composition to see how meteors with different initial velocities and masses ablate.
SOURCES OF PREBIOTIC ORGANIC COMPOUNDS Following the Urey – Miller synthesis of amino acids by spark discharge in a mixture of reduced gases
The first forms of cellular life required self-assembled membranes that were likely to have been produced from amphiphilic compounds on the prebiotic Earth, and laboratory simulations show that such vesicles readily encapsulate functional macromolecules, including nucleic acids and polymerases.
Survivability of biomolecules during extraterrestrial delivery: new results on pyrolysis of amino acids and poly-amino acids.
  • V. Basiuk, J. Douda
  • Physics
    Advances in space research : the official journal of the Committee on Space Research
  • 2001
Organic Material in Micrometeorites: Processes Affecting Its Delivery to Planetary Environments
During their delivery to Earth, extraterrestrial dust particles (EDPs) are heated via aerodynamic braking in the upper atmosphere, liberating volatile and organic species. This study investigates the
A Reassessment of Prebiotic Organic Synthesis in Neutral Planetary Atmospheres
It is shown here that contrary to previous reports, significant amounts of amino acids are produced from neutral gas mixtures, suggesting that endogenous synthesis from neutral atmospheres may be more important than previously thought.


Photochemical Production of Formaldehyde in Earth's Primitive Atmosphere
Subsequent reactions of formaldehyde in primeval aquatic environments would have implications for the abiotic synthesis of complex organic molecules and the origin of life.
Cometary delivery of organic molecules to the early Earth.
A comprehensive treatment of comet-asteroid interaction with the atmosphere, surface impact, and resulting organic pyrolysis demonstrates that organics will not survive impacts at velocities greater than about 10 kilometers per second and that even comets and asteroids as small as 100 meters in radius cannot be aerobraked to below this velocity in 1-bar atmospheres.
Shock Synthesis of Amino Acids in Simulated Primitive Environments
A mixture of gases roughly simulating the primitive terrestrial atmosphere has been subjected to shock heating followed by a rapid thermal quench. Under strictly homogeneous conditions there is a
Boundary structures are formed by organic components of the Murchison carbonaceous chondrite
The experiments reported here focused on non-polar molecules extracted from carbonaceous chrondrites, and found that certain components in the extract have physical properties which lead to the formation of boundary structures.
Origin of precursors of organic molecules during evaporation of meteorites and mafic terrestrial rocks
THE accretion of the Earth was characterized by high-temperature transformations of planetesimal matter during high-velocity impacts. In the final stages of the Earth's growth, up to 30% of
Hot Hydrogen Atoms: Initiators of Reactions of Interest in Interstellar Chemistry and Evolution
Photochemically generated hot hydrogen atoms initiate reactions with simple molecular substrates including methane to produce organic alcohols, amines, acids, amino acids, and other compounds. The
Long-Wavelength Ultraviolet Photoproduction of Amino Acids on the Primitive Earth
Hydrogen sulfide is the initial photon acceptor in this work; superthermal atomic hydrogen photodissociation products appear to initiate reactions leading to amino acid synthesis with an overall quantum yield on the order of 5X10-5.
Pre-biotic organic matter from comets and asteroids
About 20 g cm−2 intact organic carbon may have accumulated in the few hundred million years between the last cataclysmic impact and the beginning of life, which may have included some biologically important compounds that did not form by abiotic synthesis on Earth.
Possible Role of Meteorites in the Origin of Life
IT has been postulated by Oparin1 that life originated in the seas of the primitive Earth, at a time when the atmosphere was reducing. The dominant sources of free energy for biopoesis are presumed
Impact delivery and erosion of planetary oceans in the early inner Solar System
The terrestrial planets may have acquired oceans of water (and other surface volatiles) as a late-accreting veneer from impacts of comets and carbonaceous asteroids during the period of heavy