Satellites help in various scientific and technological applications.
The Satish Dhawan Space Centre located at Sriharikota (popularly called SDSC - SHAR), located in Potti Sreeramulu Nellore district, has emerged as India's primary centre for the launch of satellites. From its first launch pad on April 26, a Radar Imaging Satellite (RISAT-1) was launched into the orbit at a height of 536 kms from earth's surface. With this, India has sent 66 satellites into space in the past four decades.
Satellites are used for various scientific and technological applications. It is with satellites that rapid strides could be made in the fields of mobile communications, Direct-to-Home services, meteorological observations, tele medicine, tele education, disaster warning, radio networking, search and rescue operations, remote sensing and scientific studies of the space.
At first, satellites used optical imaging in which images of earth's surface could be taken with the help of sunlight reflection. So, night time operations were not possible. Now, radar imaging satellites are being used to send microwaves to earth's surface to capture images. Radar imaging can be used effectively during nights besides overcoming natural impediments like clouds.
With the RISAT-1 launch, it will be used for monitoring soil moisture, condition of crops, inundation due to floods and damage during cyclones. Also data can be used for studying glaciers. The SDSC SHAR has latest facilities for launch vehicle assembly, fuelling, check-out and final launch operations. To put satellites into space, scientists develop rockets which are called launch vehicles.