India on Thursday moved tantalisingly close to having its own satellite navigation system as it smoothly launched a satellite with its rocket – and is now only a step away from joining a select group of space-faring nations that have such a system. With the successful launch early Thursday of the third of seven satellites planned under the Indian Regional Navigation Satellite System (IRNSS), India is just a satellite and a couple of months away from having its own satellite navigation system. This puts India at the door step of an exclusive space club that has the US, Russia, China and Japan as members. The navigational system, developed indigenously by India, is designed to provide accurate position information service to users within the country and up to 1,500 km from the nation’s boundary line. Though IRNSS is a seven-satellite system, it could be made operational with four satellites, ISRO officials said. The fourth navigation satellite is expected to be launched this December. The entire IRNSS constellation of seven satellites is planned to be completed by 2015. Prime Minister Narendra Modi congratulated Indian Space Research Organisation (ISRO) scientists and described the launch earlier in the night as “a matter of immense pride and joy”.
Exactly at 1.32 a.m., the rocket – Polar Satellite Launch Vehicle-C26 (PSLV-C26) – standing around 44.4 metres tall and weighing around 320 tonnes, blasted off from the first launch pad here at the Satish Dhawan Space Centre, around 80 km from Chennai.
The expendable rocket with fierce orange flames at its tail lit up the night sky here. The rocket tore into the night skies with its luggage, the 1,425-kg IRNSS-1C (Indian Regional Navigational Satellite System-1C) satellite. For the onlookers, the rocket looked like an inverted flare with a long handle as it ascended towards the heavens amidst the cheers of the ISRO scientists and the
media team assembled at the rocket port here. Space scientists at ISRO rocket mission control room were glued to their computer screens watching the rocket escaping the earth’s gravitational pull. At around 20 minutes into the flight, the PSLV-C26 spat out IRNSS-1C at an altitude of around 500 km above the earth. Immediately on the successful ejection, scientists at the mission control centre were visibly relieved and started applauding happily. “India’s third navigation satellite is up in the orbit,” ISRO chairman K. Radhakrishnan said post launch. Soon after the ejection into the orbit, the satellite’s solar panels were deployed. In the coming days, four orbit manoeuvres by firing its on-board motors will be conducted by ISRO to position the satellite in the Geostationary Orbit.
The satellite has two kinds of payloads – navigation and ranging. The navigation payload would transmit navigation service signals to the users. A highly accurate rubidium atomic clock is part of the navigation payload. The ranging payload consists of C-band transponder which facilitates accurate determination of he range of the satellite. The satellite with a life span of around 10 years is the third of the seven satellites which will constitute the IRNSS. The first satellite IRNSS-1A was launched in July 2013 and the second IRNSS-1B in April 2014. Both have already started functioning from their designated orbital slots. The system, expected to provide a position accuracy of better than 20 metres in the primary service area, is similar to the global positioning system of the US, Glonass of Russia, Galileo of Europe, China’s Beidou or the Japanese Quasi Zenith Satellite System. The system will be used for terrestrial, aerial and marine navigation, disaster management, vehicle tracking and fleet management, integration with mobile phones,
mapping and geodetic data capture, visual and voice navigation for drivers and others. While the ISRO is silent on the navigation system’s strategic application, it is clear that the IRNSS will be used for defence purposes as well. By adding more satellites, the service area can be expanded, an ISRO official said.
Radhakrishnan had earlier said though IRNSS is a seven-satellite system, it could be made operational with four satellites. He had said each satellite will cost around Rs.150 crore and there will be a total of nine – seven in the space and two as stand-by on ground. The PSLV XL version used to put the satellites in orbit costs around Rs.130 crore. The seven rockets would involve an outlay of around Rs.910 crore. In addition, there will be investments made in setting up a chain of ground stations which will be around Rs.1,000 crore, Radhakrishnan had said. Once the regional navigation system is in place, India need not be dependent on others. The IRNSS will provide two types of services — standard positioning service and restricted service. The former is provided to all users and the later is an encrypted service for authorised users. The IRNSS system comprises of two segments – the space and the ground. The space segment consists of seven satellites of which three will be in geostationary orbit and four in inclined geosynchronous orbit. The ground segment consists of infrastructure for controlling, tracking and other facilities.