India launches first defence satellite

Giving a major push to the country's maritime security, India's first exclusive defence satellite, GSAT-7 was successfully launched by the European space consortium Arianespace's Ariane 5 rocket from Kourou spaceport in French Guiana yesterday.

The country's maiden dedicated spacecraft for defence applications was launched during a 50-minute launch window which started at 2 am.

The satellite was injected into a Geosynchronous Transfer Orbit (GTO) of 249 km perigee (nearest point to earth), 35,929 km apogee (farthest point to earth) and an inclination of 3.5 degree with respect to the equator after a flight of almost 34 minutes and 25 seconds duration.

The launch cost for Indian Space Research Organisation (ISRO) is around Rs.470 crore, including insurance. ISRO cannot launch heavy satellites like GSAT-7 as its home-grown GSLV rocket, with indigenous cryogenic stage, is still in in the works and needs two successful flights before it is declared operational.

According to an ISRO official, the satellite is important from security and surveillance points of views.

As planned, ISRO's Master Control Facility (MCF) at Hassan in Karnataka started acquiring the signals five minutes prior to the separation of GSAT-7 from Ariane-5 launch vehicle.

Initial checks have indicated normal health of the satellite.

GSAT-7 has a lift-off mass of 2,625 kg and is based on ISRO's 2,500 kg satellite bus with some new technological elements, including the antennae. Its solar arrays generate 2,900 W of electrical power.

The present orbit of the satellite will be raised to Geostationary Orbit of about 36,000 km altitude through three orbit raising manoeuvres by firing of GSAT-7's Liquid Apogee Motor (LAM). Preparations are underway for the first firing, planned in the early hours of 31 August 2013. The satellite will be placed in the Geostationary Orbit by 4 September 2013.