Possible chemical impact of planetary lightning in the atmospheres of Venus and Mars [2]

THE importance of lightning as a source of trace gases in the Earth's atmosphere has long been recognised. In 1827, von Liebig proposed lightning as a source of atmospheric fixed nitrogen1 and recent investigations have supported this hypothesis2-7. In the Earth's pre-biological atmosphere lightning may have produced organic molecules, such as HCN, which led to the evolution of life8. After life evolved, but before photosynthesis and biological nitrogen fixation developed, lightning may have provided an abiotic source of organic C and fixed N to the growing biota 9,10. The presence of cloud layers on Venus11 and synoptic scale dust storms on Mars12 suggest that lightning may also occur on these planets, and indeed there have been reports of lightning being detected on Venus by American and Soviet spacecraft. The implications for atmospheric chemistry of lightning on Venus and Mars are discussed here. © 1979 Nature Publishing Group.

Duke Scholars

Author William Chameides Earth and Climate Sciences