Investigation of internal gravitational waves by an infrared camera of the entire sky over the territory of Yakutia

Internal gravitational waves are space-time fluctuations of air masses in the atmosphere. In addition to the longitudinal component, they also have a transverse component, which distinguishes them from ordinary acoustic waves. Significant progress has been made in the study of atmospheric dynamics over the past decades. Solving large-scale wave movements of air masses, particularly internal gravitational waves, remains a complex and urgent task. Spatial heterogeneity was studied to identify internal gravitational waves in the emission of the glow of the night sky at an altitude of about 87 km, where bands of hydroxyl molecules are emitted. The waves were recorded using an infrared digital camera of the whole sky installed at the optical polygon of Maymag (Yakutia). Data processing was performed by the method of temporal differentiation of images. One thousand one hundred forty frames were obtained for two seasons (2016-2017 and 2017-2018) with a pronounced wave periodic structure defined as internal gravitational waves. For each case of detected internal gravitational waves, the following parameters were determined: wave period, wavelength, propagation velocity, the direction of propagation, time, and duration of observation. The lengths of the recorded waves vary from 9.6 to 52.5 km (the average value is 25 km), the estimated periods range from 4.5 to 13.3 min (the average value is 7 min) and wave propagation is directed mainly to the northwest.