Origins of life

, Volume 8, Issue 3, pp 259–266 | Cite as

Far UV irradiation of model prebiotic atmospheres

  • G. Toupance
  • A. Bossard
  • F. Raulin


UV light has been the most important energy source on the primitive Earth. However, very few experiments have been performed to test directly the possible role of this energy source on the chemical evolution of the primitive atmosphere, mainly on account of experimental difficulties. Experiments are generally performed with other excitations, mainly electric discharge, and it is frequently assumed that UV irradiation would give similar results.

As theoretical considerations make this assumption questionable, direct experimental controls have been undertaken: Model primitive atmospheres have been submitted to 147 nm UV light and the gaseous phase has been analysed. Preliminary qualitative results concerning CH4−NH3 atmospheres are reported.

Irradiation of pure CH4 gives rise to the synthesis of a large number of hydrocarbons, mainly saturated hydrocarbons but including also unsaturated ones as, C2H2, C2H4, C3H6, C3H4. These insaturated hydrocarbons are synthetized at a very low rate when ammonia is present in the medium.

Irradiations of CH4−NH3 mixtures give rise, in addition to hydrocarbons, to important amounts of HCN (about 0.1%) and to lesser amounts of CH3CN and C2H5CN. No unsaturated nitriles such as acrylonitrile and cyanoacetylene have been detected. Search for amines is in progress.

These results evidence that UV irradiation may contribute largely to synthesis of HCN in CH4−NH3 atmospheres and, consequently to the synthesis of many biochemical compounds that can be derivated from HCN. However, synthesis of other compounds, such as pyrimidines, which can derivate from other nitriles, such as cyanoacetylene, cannot be initiated only by UV light, contrary to electric discharges. In addition, if electric discharges are very efficient for synthesis of nitriles in CH4−N2 atmospheres, there is not yet evidence that UV light is able to do so.


Hydrocarbon Nitrile Pyrimidine CH3CN Electric Discharge 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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  1. Bark, L. S. and Higson, H. G.: 1964,Talanta 11, 621.Google Scholar
  2. Braun, W., MacNesby, J. R. and Bass, A. M.: 1967,J. Chem. Phys. 46, 2071.Google Scholar
  3. Dodonova, M. Yu and Sidorova, A. I.: 1961,Biofizika 6, 149.PubMedGoogle Scholar
  4. Donnelly, R. F. and Pope, J. H.: 1973, NOAA Technical Report ERLZ 76-SEL 25, US Govt. Printing Office, Washington, D.C. 20402.Google Scholar
  5. Ferris, J. P., Sanchez, R. A., and Orgel, L. E.: 1968,J. Mol. Biol. 33, 693.PubMedGoogle Scholar
  6. Ferris, J. P. and Chen, C. T.: 1975a,J. Amer. Chem. Soc. 97, 2962.Google Scholar
  7. Ferris, J. P. and Chen, C. T.: 1975b,Nature,258, 587.Google Scholar
  8. Ferris, J. P., Nakagawa, C., and Chen, C. T.: 1976, 19th Cospar Meeting, 18–19 June, Philadelphia.Google Scholar
  9. Groth, W. E. and Von Weyssenhoff, H.: 1960,Planet. Space Sci. 2, 79.Google Scholar
  10. Hellner, L. and Vermeil, C.: 1970,J. Chim. Phys. 221.Google Scholar
  11. Hubbard, J. S., Hardy, J. P., Voecks, G. E., Golub, E. E.: 1973,J. Mol. Evol. 2, 149.PubMedGoogle Scholar
  12. Oro, J.: 1963,Fed. Proc. 22, 681.Google Scholar
  13. Raulin, F. and Toupance, G.: 1976,Bull. Soc. Chim. Fr., 667.Google Scholar
  14. Sagan, C. and Khare, B. N.: 1971,Science 173, 417.Google Scholar
  15. Toupance, G.: 1973,Thèse de Doctorat d'État. Université Paris VIGoogle Scholar
  16. Toupance, G., Raulin, F., and Buvet, R.: 1975,Origins of Life 6, 83.PubMedGoogle Scholar
  17. Watanabe, K., Zelikoff, M., and Inn, E.C.Y.: 1953,A.F.C.R.C., Technical Report No. 53-23.Google Scholar

Copyright information

© D. Reidel Publishing Company 1977

Authors and Affiliations

  • G. Toupance
    • 1
  • A. Bossard
    • 1
  • F. Raulin
    • 1
  1. 1.Laboratoire d'Energétique BiochimiqueUniversité Paris Val de MameCreteilFrance

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