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Zenith-directed Fabry-PerotSpectrometer (FPS) and 3-Field Photometer (3FP) observations of the&#x03BB;630 nm emission (~240 km altitude) were obtained at Davisstation, Antarctica, during the austral winter of 1999. Eleven nights ofsuitable data were searched for significant periodicities common to verticalwinds from the FPS and photo-metric variations from the 3FP. Three wave-likeevents were found, each of around one or more hours in duration, with periodsaround 15 minutes, vertical velocity amplitudes near 60 ms–1 ,horizontal phase velocities around 300 ms–1 , and horizontalwavelengths from 240 to 400 km. These characteristics appear consistent withpolar cap gravity waves seen by other workers, and we conclude this is a likelyinterpretation of our data. Assuming a source height near 125 km altitude, wedetermine the approximate source location by calculating back along the wavetrajectory using the gravity wave property relating angle of ascent andfrequency. The wave sources appear to be in the vicinity of the poleward borderof the auroral oval, at magnetic local times up to 5 hours before local magneticmidnight. Key words. Meteorology andatmospheric dynamics (thermospheric dynamics; waves and tides

Evidence for thermospheric gravity waves in the southern polar cap from ground-based vertical velocity and photometric observations