Sodium Layer Heights Over Antarctica

Abstract

Measurements of the twilight sky luminosity variations in Na D at Saskatoon, Canada, were found by Hunten and Shepherd (1954) to be consistent with a distribution of sodium atoms centred at a height of 85 km with a scale height of 7·5 km above and below the peak, the luminosity being due to resonance scattering of sunlight. By fitting Hunten's (1954) luminosity curve to experimental data obtained in Australia and Antarctica, O'Brien (1960) found a sodium layer height of90±5 km