Structure of the Primordial Atmosphere Surrounding the Early-Earth

Abstract

We investigate the structure of the primordial atmosphere surrounding the early-Earth under various conditions. We put a special emphasis on stages where the Earth had already grown to the present mass and the gas of the solar nebula was escaping. The atmosphere is assumed to be in hydrostatic equilibrium and spherically symmetric. The structure depends on the energy out flow (i.e., the luminosity) of the Earth, the gas density of the solar nebula, and the abundance of dust grains contained in the atmosphere. Calculations are made for a wide range of these three parameters. Detailed numerical results for various quantities such as the density and the temperature at the bottom of the atmosphere, the position of the photosphere and the atmospheric mass are tabulated. Distributions of density and temperature are also given. Atmospheric models obtained here will provide basic data for the study of dissipation of the primordial atmosphere and for that of the lunar capture. © 1985, Society of Geomagnetism and Earth, Planetary and Space Sciences. All rights reserved.