Indian National Satellite System

The Indian National Satellite System or INSAT in short is a series of many geostationary satellites. They were launched by the Indian Space Research Organisation (ISRO) for multiple purposes like telecommunications, broadcasting, meteorology, and search and rescue operations. INSAT was commissioned in 1983. It is the largest domestic communication system in the Indo-Pacific region. The satellites are made possible by the Department of Space, Department of Telecommunications, India Meteorological Department, All India Radio and Doordarshan. The operations of the INSAT system are handled by the Secretary-level INSAT Coordination Committee.

INSAT satellites provide transponders used for communication to serve the television and communication needs of India. Some of the satellites also have devices like VHRR, CCD cameras to take weather pictures. The satellites also help in receiving distress alert signals to help in search and rescue missions in South Asia and the Indian Ocean, as ISRO is a member of the Cospas-Sarsat program.

INSAT started with the launch of INSAT-1B in August 1983. INSAT-1A, the first satellite with 'A' in its name, was launched before 1B in April 1982 but it did not work. INSAT system helped improve television, radio, phone services and weather forecasting in India, even in remote areas and islands. Some of the INSATs also carry instruments for meteorological observation and data relay for providing meteorological services. KALPANA-1 satellite is used specially only for weather. The satellites are controlled by Master Control Facilities that exist in Hassan and Bhopal.