Page 15 - April 2021
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         We certainly need more efforts in the development of launch vehicles using semi cryogenic fluids — kerosene as the fuel and liquid oxygen as the oxi- dizer. This combination could result in much lesser cost as well as reduced atmospheric pollution levels.
BUILDING OUR OWN SATELLITES
Dr Sarabhai was convinced that we could use a Television Broadcasting satellite to deliver educational and instructional programmes. Studies were un- dertaken to define the overall system. It was planned that as a first step we will be using the NASA Applications Technol- ogy Satellite F and later this was to be followed by our own operational system.
After the untimely death of Dr Sarabhai in 1971, the ISRO was led very handsome- ly by Prof Satish Dhawan. The Satellite Instructional Televi- sion Experiment — SITE — was successfully conducted in 1975-1976.
ASLV or the Augmented Satellite Launch Vehicle, one of India’s earliest launch vehicles to be tested, at the site
to be launched in April 2021, will enhance our capability fur- ther. When it was realised that we could not depend on the as- sured availability of the Global Positioning Satellite (GPS) sys- tem, we went ahead with our own Indian Region Navigation Satellite System, the IRNSS or NAVIC. In addition to the pro- vision of the navigation data, our system also provides data for our fishermen. Successful integration of the NAVIC chips in addition to the GPS in GSM or CDMA mobile communi- cation handsets will result in further extensive utilisation of the system.
The development, fabrica- tion and launch of very complex missions such as the Chandray- aan, Mangalyaan and Astro- sat have indicated our resolve to remain on the forefront of the technology. The successful completion of the Chandrayaan III and Aditya missions will add to ISRO’s prestige.
NASA’s Hubble Space Telescope, which completely revolutionised the space astron-
The INSAT system was conceived with the utilisation of the operational multipurpose geostationary satellites. For INSAT 1, the first series of the mul- tipurpose satellites, ISRO had defined the basic specifications and the satellites were built by Ford Aerospace Communi- cation Corporation of USA. While it was recognised that we will have to get our first series of operational communica- tion satellites from foreign sources, our efforts to develop and fabricate our own satellites indigenously were undertaken parallelly.
The initial development of satel- lites was started in ISRO to provide the Rohini Technical Payload for the SLV 3 launch vehicle and to realise the first scientific satellite, Aryabhata, in 1975. This was very quickly followed by the Bhaskara satellite, Ariane Passenger Payload Experiment (APPLE), Indian Remote Sensing Satellites, and Indian
National Satellite INSAT II series. ISRO has developed the complete capability of building satellites of any kind needed. These include the CARTOSAT, Hyper Spectral imaging satellite and Radar Imaging satellites. A large number of countries routinely use data of the earth imaging capabilities of our satellites.
The Meteorological Earth images taken by our satellites are being used ex- tensively since 1983, for example, in the prediction of monsoon and detection of cyclones. The latest GIASAT, expected
The Meteorological Earth images taken by our satellites are being used since 1983, for example, in the prediction of monsoon and detection of cyclones.
omy, has now stopped functioning. The launch of NASA’s James Webb Space Telescope is delayed. Today, the Astro- sat developed by ISRO, Tata Institute of Fundamental Research (TIFR)and Inter University Centre for Astronomy and Astrophysics is providing the neces- sary data.
SPACE AND NATIONAL SECURITY
ISRO has contributed extensively in providing necessary tools and informa- tion for national security. Its space com- munication systems and earth observa- tion systems are extensively used by our security and defence agencies. ISRO has developed and delivered specific satellites for our defence needs of communications and earth observations in any weather conditions. Our communications in the remote border areas as well as island ar- eas are extensively dependent on the use of our satellites.
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