Isro's Fourth Navigation Satellite to Be Mated With Rocket This Week

The Indian space agency is hoping to mate the country's fourth regional navigation satellite around March 19, after replacing a faulty transmitter on Monday, said a senior official.

"The new transmitter is expected to be fixed in the satellite and tested. Then the fully assembled satellite will be mated with the rocket," M.Y.S. Prasad, director of Satish Dhawan Space Centre (SDSC) told IANS over phone.

The transmitter from Isro Satellite Centre, located in Bangalore and that is part of Indian Space Research Organisation (Isro), reached SDSC on Sunday.

After mating the satellite with the rocket, a full system check would be carried out and then the rocket launch date would be fixed.

Prasad said if everything goes well then the space agency is planning to launch the rocket towards the end of March.

The 1,425kg satellite - Indian Regional Navigation Satellite System (IRNSS-1D) - was supposed to be launched on the evening of March 9 by an Indian rocket called Polar Satellite Launch Vehicle (PSLV-XL).

The Isro on March 4, however, deferred the launch after it found one of the telemetry transmitters in the IRNSS-1D not working properly.

Subsequently, the satellite was dismounted from the rocket to attend to the technical glitch.

It is the first time in Isro's history that a satellite had to be dismounted from a rocket due to a problem in it.

Prior to this incident, satellites have been dismounted from a rocket but due to other problems.

India has so far launched three regional navigational satellites as part of a constellation of seven satellites to provide accurate position information service to users across the country and the region, extending up to an area of 1,500km.

Though the full system comprises nine satellites - seven in orbit and two on the ground as stand-by - the navigation services could be made operational with four satellites, Isro officials had said.

Each satellite costs around Rs. 150 crores and the PSLV-XL version rocket costs around Rs. 130 crores. The seven rockets would involve an outlay of around Rs. 910 crores.

The entire IRNSS constellation of seven satellites is planned to be completed by 2015.

The first satellite IRNSS-1A was launched in July 2013, the second IRNSS-1B in April 2014 and the third on October 16, 2014.

Once the regional navigation system is in place, India need not be dependent on other platforms.