A preliminary model atmosphere based on rocket and satellite data

The scientific results obtained from rocket and satellite observations have been studied in order to determine the physical properties of the atmosphere at high altitudes. A preliminary model atmosphere is presented for the region between 100 and 800 km. The paper contains numerical tables of density, pressure, and scale height as functions of altitude. Due to solar effects these physical parameters may vary from day to night and from latitude to latitude. However, preliminary studies have indicated that average densities and pressures might vary by at most a factor of two, the variations being larger at high than at medium latitudes. Densities presented by Russian scientists, which were also obtained from rocket and satellite data, agree with the model density presented here reasonably well. The densities derived by American and Russian scientists from satellite observations agree within less than a factor of two. The densities derived from rocket data are lower than the ones derived from satellite data for the same altitude. The maximum difference between the densities derived by Michnevich [1958] from rocket data and the average densities presented here occur around 150 km, where the values differ by a factor of 3.8; above and below these altitudes the differences are much less. It is estimated that these differences then are within the limits of the variations to be expected and also within the limits of the uncertainties of the experimental data available at present.