First Indian astronomical observations in Antarctica

Extract

An Indian expedition to Antarctica (to the coastal base Maitri) in the 1989/90 summer made observations of the Sun to study the evolution and decay of supergranules, an experiment which benefited greatly from uninterrupted sessions of a few days. The instrument comprised a heliostat, a 1.2 Å bandwidth blue filter, and a 10 cm aperture lens of about 3 metre focal length with recording on film. During January and February, one continuous period of more than 100 hours completely clear sky occurred, during which the transparency of the atmosphere was excellent. However, at times the seeing was a little poor. More than 2500 photographs were made at 10 minute intervals, as well as some at shorter intervals for studying the evolution of other solar features such as flares.