As Earth cools, water in the atmosphere condenses: torrential rains fall on, and on, and on. Great seas form. Exuberant volcanoes expel hotly agitated deep earth to the surface.
The hot, early atmosphere dances with an abundance of carbon dioxide, nitrogen, and water, and lesser amounts of methane and ammonia. Intense energy sources available on the primitive Earth form biologically important molecules from these gases. Candidate sources include solar UV-radiation (there is as yet no UV-protective ozone shield), radioactivity, and hot oceanic vents.
University of Montana--Missoula. Environmental Studies Program
© 1997 Stiftung Drittes Millennium
Digital File Format
Digital Image Number
Liebes, Sid; Mittelstadt, Laurie; Waugh, Barbara; and Brynes, Lois, "Panel 08: The Rains Reign" (1997). A Walk Through Time - From Stardust To Us. 8.