Gravity waves from sodium-dayglow observations

The sampling interval of sodium dayglow observations was progressively reduced from one hour to two minutes for investigation of mesospheric dynamics, especially for daytime detection of the periods of gravity waves in the mesosphere and the lower thermosphere. The observations were analysed by usual power spectrum technique. The prominent periods, observed for the present, vary between 5 to 27 minutes in general agreement with results obtained by other techniques.