Balmer alpha and Lyman beta in the hydrogen geocorona

The spherical Lyman-β radiative transfer problem is solved for several theoretical models of the hydrogen geocorona. Comparisons of the computed intensities with the experimental observations of Lyman β and Balmer α airglows show that the geocoronal Balmer α contribution is superimposed on a uniform background of about 4 R. The 4 R background is probably galactic (or extra-galactic) in origin. The column density of hydrogen required to account for the telluric Balmer α component is about 5 × 1013 atoms per cm² above 650 km for a 950°K exosphere.