Sriharikota, Dec 25 (IANS) Advanced communication satellite GSAT-5P, which will ensure continuity of telecom, television and weather services after an earlier satellite is retired, will be launched at the Sriharikota rocket launch centre Saturday evening.

If all goes well, the rocket geosynchronous satellite launch vehicle (GSLV) will lift off at 4.04 p.m. Saturday, said an official of the Indian Space Research Organisation (ISRO).

The progress to launch the Rs.125 crore (Rs.1.25 billion) GSAT-5P satellite weighing 2,130 kg has been smooth.

The satellite will serve the needs of the telecommunication sector and the weather department. It will eventually retire the INSAT-2E satellite that was sent up in 1999.

The Sriharikota rocket launch centre is about 80 km from Chennai.

‘We have completed filling of liquid fuel in the four strap on motors and the second stage of the rocket. Fuel filling activities for the cryogenic engine have started,’ the official told IANS.

The filling of liquid fuel was completed around 2 a.m. Saturday. ‘We have filled a total of 206 tonnes of fuel,’ the official said.

The GSLV rocket has three stages. The first stage is fired by solid fuel. The four strap on motors give additional thrust during the lift-off and the initial phase of the rocket’s flight.

The second stage is fired by liquid fuel. The third stage, which is more complex than the others, involves the cryogenic engine powered by liquid hydrogen as fuel and liquid oxygen as oxidiser.

The GSLV rocket is 51 metres tall and weighs 418 tonnes.

The GSAT-5P satellite, with a life span of over 13 years, has 36 transponders – automatic receivers and transmitters for communication and broadcast of signals. Its successful launch will take the agency’s transponder capacity to about 235 from the 200 currently in the orbit.

ISRO has the following communication satellites in service – INSAT 2E, INSAT 3A, INSAT 3B, INSAT 3C, INSAT 3E, INSAT 4A, INSAT 4CR and INSAT 4B working at 50 percent capability.

ISRO launched two major satellites in 2010 – communication satellite GSAT-4 and remote sensing satellite Cartosat-2.

The GSAT-4 launch failed after the rocket crashed into the Bay of Bengal while Cartosat-2 was placed successfully in the orbit.