Indian satellites which were developed since 1975 had been one of the biggest achievements of modern day space technology. Indian satellites launched by Indian space research organisation (ISRO) have been largely oriented towards telecommunication, broadcasting, meteorological, search and rescue which serve the immediate need of India. For this purpose ISRO launched a number of satellites for the domestic purposes which were commonly known as INSAT series or Indian National Satellite System. While India`s first experience was visible with the launching of Aryabhata which provided technical knowledge in building and operating a satellite system; this was further developed with launching of number of other satellites which followed Aryabhata.
Indian satellites marked a difference with the launching of Aryabhata. Till the launching of Aryabhata India was engaged in manufacturing Satellite launching vehicles this would provide the speed and set the orbit for the satellite. This was successfully experienced in case of launching of Aryabhata. The first Indian Satellite Aryabhata was then followed by Bhaskara I which was launched after Aryabhata. This was the first remote sensing satellite which carried TV and Microwave Cameras. Following this India launched Rohini family which contained payloads .These were the first hi flight satellites which were tested by India with SLV3 satellite launchers.
However they could not reach their orbit. Finally Indian scientists developed the Arian passage Payload experiment which was successful in providing the technology to develop a three-axis stabilised communication satellite. This paved the way for Bhaskara II which was the first successful satellite developed for hi flight communication and remote sensing system.
Indian satellites marked a new phase of development within Indian Communication system. This was largely carried out by INSAT group which was developed since 1983 in India. This began with INSAT 1A the first operational multipurpose communication satellite which could also project meteorological information. This further developed with the rest of the INSAT satellites that followed the race. Every new satellite brought a revolution in Indian communication system. Following this India then launched IRS group of Satellites which were developed in 1988 as first Earth observing satellite. This was relevant for the security of the country. This was followed by a number of Satellites which was launched to observe the reaction of Infrared rays and gamma ray s which could be utilised for the satellites. The meteorological satellite was renamed as Kalpana after Kalpana Chawla in2004.
Thus the list of Indian satellites which range up to 50 had marked a revolution in Indian Space technology. This has been the most important and relevant discovery which was necessary to make India competent with the world.