INSAT-4B launched successfully

India’s telecommunication satellite INSAT-4B was successfully launched yesterday from the spaceport of Kourou in French Guiana by European Ariane 5 launch vehicle, giving a boost to direct-to-home (DTH) television services in India.

The 3,025 kg spacecraft rode space with co-passenger British military satellite Skynet-5A on board the commercial launch service provider Arianespace’s Ariane 5 rocket early on Monday morning at 03:33 Indian Standard Time (IST).

The Rs 2.1 billion satellite built by Bangalore-headquartered Indian Space Research Organization (ISRO) is equipped with 24 communication transponders that would augment the capacity for DTH television services and other communication and TV services in India.

“About 30 minutes after lift-off, INSAT-4B was placed in the geosynchronous transfer orbit in 3-axis stabilized mode. INSAT-4B is now orbiting with a perigee (nearest point to earth) of 243 km and an apogee (farthest point to earth) of 35,876 km and an inclination of 4.52 degree with respect to the equator. The orbital period is about 10 hours 34 minutes”, said a press release from ISRO.

The Master Control Facility (MCF) at Hassan in Karnataka acquired the first signals from INSAT-4B at 04:02 IST. “The initial checks on the satellite have indicated normal health of the satellite. The MCF subsequently issued commands to the satellite to make the earth viewing face to orient towards the earth”, the statement added.

“It is a great occasion for us today”, said ISRO Chairman G Madhavan Nair in a post-launch statement issued from Kourou. “I have information from MCF that signals received from the satellite are extremely good. We believe that in the next few days, we should be able to raise the orbit to the synchronous heights of 36,000 kms”, he added.

INSAT-4B is being tracked, monitored and controlled from MCF. “In the coming days, INSAT-4B will be maneouvred to its final geostationary orbit, which is about 36,000 kms above the equator, by firing its 440 Newton Liquid Apogee Motor (LAM)”, the ISRO statement said.

Monday’s launch of INSAT-4B comes after a 24-hour delay following an operational anomaly at the launchpad, detected minutes before the lift-off scheduled for early Sunday. The lift-off was initially put on hold due to the anomaly. When the anomaly could not be rectified within the 33 minute launch window slated to open at 3.55 am on Sunday, the launch was put off to Monday.

Meanwhile, ISRO officials said the 24 new transponders on board the INSAT-4B would add to the existing 175 transponders already in the orbit, taking their total strength to 199. Even before the launch, ISRO had sold each transponder for about one million dollars for a year and rake in a revenue of about Rs 12.5 billion. The communication satellite has a life-span of about 12 years.

The transponders receive signals, translate their frequency and amplify them before re-transmitting them back to earth. The re-transmitted signal can be accessed anywhere in India. Each transponder will cover thousands of television sets, ISRO officials said. “All the transponders have been booked by various operators even before the launch”, the officials added.