Noctilucent clouds over the Arctic in November


  • Arnold M. Hanson


The observations described below were made from ice island T-3 before and after local midday of November 12, 1964. T-3 was located at 79°35′N and 137°058W. Local midday was approximately 2056 UT. At local noon, the zenith distance of the sun was 97°28.6′.

The clouds were first observed at 1044 LST (Local Solar Time), at which time they were mistaken for cirrostratus. However, with so large a solar depression, cirrostratus could not have been sunlit. Some photographs, both black and white and color, were taken between 1114 and 1124 (Figure 1), but systematic observations began at 1134. Photographs were taken at 15-min intervals from 1134 until 1404 (excepting 1319). Additional photographs were taken at 1253, 1326, and 1429. After 1434, the display became obscured by lower clouds.