Indian Space Research Organisation (ISRO) successfully placed advanced weather satellite SCATSAT-1 and seven other satellites in orbits in its longest ever launch mission, which spanned over two hours and 15 minutes.
It is for the first time that satellites were placed in two different orbits with a single rocket. Vikram Sarabhai Space Centre director K Sivan said, “The rocket has placed all the satellites in precise orbits.”
The Polar Satellite Launch Vehicle (PSLV-C35) carrying the eight satellites took off from Satish Dhawan Space Centre in Sriharikota at 9.12am. Around 17 minutes later, SCATSAT-1, the main payload of PSLV in its 37th flight, was placed in the polar sun synchronous orbit at an altitude of about 730km.
SCATSAT-1, which will provide weather forecast including cyclone detection and tracking, will succeed the now defunct Oceansat-2 satellite launched in 2009. Isro chairman A S Kiran Kumar said SCATSAT-1 would be a stop gap arrangement between Oceansat-1 and Oceansat-2.
After the first satellite injection, PSLV-C35 coasted for an hour before its fourth-stage engine was reignited and shut down, for about 20 seconds. This provided the rocket the necessary thrust to coast into the polar orbit at an altitude of 689km.
Again, after an hour, the engine was restarted and cut off within a period of about one minute for it to further coast. It then began injecting the rest of the satellites. They included two satellites developed by educational institutions — Pratham from IIT-Bombay and Pisat from PES University, Bangalore, and its consortium — and five other commercial satellites from Algeria, Canada and the US.