Ground-based Measurements of Mesosphere Temperatures by Optical Means

The determination of the rotatinal temperature of the molecular emissions of OH or O2 offers a means of observing from the ground the mesosphere temperature at about 90 km throughout the night. The techniques and optical instrumentation developed to carry out these measurements are described. In comparison with other methods for the observation of this important geophysical quantity the optical technique is inexpensive and readily applicable for automatic operations over a long time period.