Primitive Atmosphere of the Earth

THIS communication reports the results of calculations on the temperature structure in a model of the primitive atmosphere, which suggest that during the early history of the Earth a reducing atmosphere could be stable against gravitational escape for as long as 10 9 yr. These results may help partly to resolve the considerable amount of controversy in the literature about the composition of the atmosphere of the Earth 3 × 10 9 −4 × 10 9 yr ago when the first living organisms are thought to have been synthesized.