Developments of Space Astronomy in India

Abstract

The universe is pouring out information on its extent, structure, composition, variety of objects, their relative motions, their temperatures, time variations, the electric and magnetic fields in the various regions, the physicochemical and biological evolutionary chains and a host of other details, in the form of a variety of particulate and electromagnetic, radiations, neutrino and perhaps exotic particles yet unidentified, and has left it to the ingenuity of man to record these radiations and come out with a consistent, meaningful understanding of the origin, the fundamental constituents and the forces behind the vast range of phenomena witnessed. In this endeavour naked eye astronomy was naturally the oldest dating back to several millennia, followed by telescopic observation starting with Galileo in the 16th century, spectroscopic observations of celestial objects planets and stars in the 19th century. The installation of the large telescopes at Mount Wilson and Mount Palomar in California were landmark events in the long history of optical astronomy. A vast amount of data has been collected and analysed and very many intricate aspects of the universe have been figured out on the basis of optical astronomy alone eventhough it is based on an extremely narrow band of the electromagnetic spectrum. In the 1930s, serendipitously a new window of astronomy opened up radio astronomy which has supplemented and complemented optical astronomy through the discovery of a vast range of phenomena not seen in optical astronomy. A flavour of the type of new results from radio astronomy window is available in the accompanying chapter by Prof. Swarup.