first_imgA study has been made of vertical thermospheric winds in the vicinity of Halley, Antarctica (75.5°S, 26.8°W; L = 4.2). Strong downward winds, up to 50 m s−1, are frequently observed when the station is located under the equatorward edge of the oval. Whether there is a net downwards motion throughout the night is discussed, and it is concluded that this is probable. The consequent effects upon thermospheric composition and ionospheric electron concentration are also discussed, and related to observations made at Halley.last_img read more