A NEW METHOD OF DETERMINING THE MEAN MOLECULAR MASS,

A method is described for determining the mean molecular mass of atmospheric gases which is particularly useful above 100 km. The density scale height, D, and pressure vertical gradient, P, are measured by means of the orbital decay of conventional satellites and the spin decay of paddlewheel satellites in highly eccentric orbits. These quantities are inserted in the equation DHCl P to obtain H, the pressure scale height. Temperatures measured by several different methods are used with H to obtain the mean molecular mass, M, by the equations H kTmg and M 6.02 10 to the 23rd power m, where k is Boltzmanns constant, T is the absolute temperature, m is the mass in grams of a single molecule, and g is the local acceleration in gravity.