Cheni, Sept 24: The countdown for the launch of an Indian rocket with a weather and seven other satellites began on Saturday at rocket port Sriharikota in Andhra Pradesh, the Indian space agency said.
According to the Indian Space Research Organisation (ISRO), the countdown for the launch of the Polar Satellite Launch Vehicle (PSLV) began at 8.42 a.m.
This will be ISRO’s longest PSLV satellite launch mission spread over two hours and fifteen minutes.
The 320 tonne PSLV rocket carrying eight satellites - three Indian and five foreign - will blast off from the first launch pad at Sriharikota on September 26 at 9.12 a.m.
The rocket’s main cargo will be the 371 kg SCATSAT-1 for ocean and weather related studies which will be placed into a 730 km polar sun synchronous orbit around 17 minutes into the flight.
According to ISRO, SCATSAT-1 is a continuity mission for Oceansat-2 scatterometer to provide wind vector data products for weather forecasting, cyclone detection and tracking services to the users..
The mission life of the satellite is five years.
The five foreign satellites are: three from Algeria (Alsat-1B 103kg, Alsat-2B 117kg, Alsat-1N 7kg); and one each from Cada (NLS-19, 8kg) and the US (Pathfinder-44kg).
The two other Indian satellites are: Pratham (10kg) built by Indian Institute of Technology - Bombay and Pisat (5.25 kg) from PES University, Bengaluru and its consortium.
This is the first mission of PSLV in which it will be launching its payloads into two different orbits. Two hours and 11 minutes into the flight the fourth stage will be restarted. Four minutes later all the seven satellites would be put into their intended orbit.
The PSLV rocket is a four stage/engine rocket powered by solid and liquid fuel altertively.
“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,” an industry expert 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,” the expert added. (IANS)