Indian Space Research Organization (ISRO) on Monday, 26th September will launch its weather satellite SCATSAT-1 with other seven satellites with its Polar Satellite Launch Vehicle (PSLV) , said the Indian space agency.
According to ISRO, the countdown for the launch began today at 8:42 am. This time it will be ISRO’s longest PSLV satellite launch mission over two hours and fifteen minutes.
The weight of the PSLV rocket is 320 tonne and it carrying eight satellite; three Indian and five foreign. It will launch from the first launch pad at Sriharikota in Andhra Pradesh at 9:12 am.
An ISRO official told IANS that the main cargo of the rocket will be 371 kg SCATSAT-1 for ocean and weather related studies which will be placed into a 730 km polar sun synchronous orbit. It is a continuity mission for Oceansat-2 scatterometer which will provide wind vector data products for cyclone detection, weather forecasting and tracking services to the users.
The satellite will carry Ku-band scatterometer which is similar to the one flown on board Oceansat-2.
The five foreign satellites are from Algeria, the US and Canada.
Three from Algeria- Alsat-1B 103kg, Alsat-2B 117kg, Alsat-1N 7kg; one from the US- Pathfinder-44kg and one from Canada- NLS-19, 8kg.
Two India satellites are PES University, Bengaluru and its consortium’s Pisat (5.25 kg) and Pratham (10 kg) which is built by Indian Institute of Technology – Bombay.
This is PSLV’s first mission in which it will launch its payloads into two different orbits.
Alternatively liquid and solid fuel power up the PSLV rocket and it is a fourth stage/engine rocket.
This is not the first time ISRO used the multiple burn technology (switching on and switching off of the rocket’s fourth stage). Earlier, on 16th December, 2015, ISRO first tested the technology while flying its PSLV rocket.
An industry expert said to IANS, “Restarting a rocket engine soon after it is shut off is a critical technology that has to be mastered. Once a rocket engine is activated, then the heat generated is very high. The trick is to cool it down in space and to restart it at a short gap.”
He further said, “This is entirely different from switching on and off the communication satellite’s engines in space. The interval between two restarts of a communication satellite engine will be in days. But in the case of restarting a rocket engine, the time gap will be in hours.”
He anxiously stated that during the restart time the engine has to be cooled down and this time the experiment is really very critical.