ISRO to launch 2 small satellites for UK today

The Indian Space Research Organisation (ISRO) is set to launch two small earth observation satellites for the United Kingdom on Sunday. NovaSar and S1-4, weighing a total of 889 kg, will be set off from the first launch pad at Satish Dhawan Centre, Sriharikota at 10:00 pm into a 583-km sun-synchronous orbit. A satellite is said to be in a sun-synchronous orbit when it changes its orientation throughout the year to ensure that the angle of sunlight is the same every time it passes over a particular geographical area on the surface of the earth. S1-4 is a high-resolution optical earth observation satellite weighing 444 kg. It will improve UK’s disaster monitoring capabilities. The satellite will also be used for monitoring the environment and resources. NovaSar, weighing 445 kg, carries a Synthetic Aperture Radar that can be used for mapping of the earth surface and will be used for mapping forests, land use and ice cover. It will also help in monitoring floods. It will be used for monitoring the environment, surveying resources and urban management, and for disaster monitoring. The satellites will be carried aboard India’s workhorse, the Polar Satellite Launching Vehicle (PSLV - C42), which has launched 52 Indian and 237 commercial international satellites in a span of 25 years. This mission will use the lightest core-only configuration of PSLV, which does not have the six additional solid-straps on motors. This is a commercial mission under ISRO’s Antrix Corporation Limited. It comes after a five-month hiatus following the launch of the seventh satellite (IRNSS 1I) in India’s regional navigational satellite constellation — NavIC — in April. Just before that ISRO had lost a replacement satellite IRNSS-1H for the same constellation after its heat shield did not open on time, had lost communication with an advanced communication satellite GSAT-6A, and had to recall a satellite to be launched from French Guiana weeks before its scheduled launch. ISRO has lined 19 missions till March 2019. Source: Hindustan Times