India's most advanced INSAT-4A telecommunication satellite was successfully launched by the European generic rocket, Ariane-5, from the spaceport of Kourou in French Guyana at 0403 IST on Thursday.
The launch is seen as another milestone in India's space programme and is expected to give a major fillip to Direct-to-Home television services.
INSAT-4A, India's heaviest satellite weighing 3,080 kg at lift-off, was shot into space about 29 minutes after the European launch vehicle blasted off.
The rocket also deployed INSAT-4A's co-passenger, European meteorological payload MSG-2 seven minutes later.
Soon after the launch, the Master Control Facility at Hassan in Karnataka picked up the signals from INSAT-4A at 0432 IST and Indian Space Research Organisation Chairman G Madhavan Nair, who witnessed the launch, described the health of the satellite as 'good'.
Describing the INSAT-4A launch, telecast live by Doordarshan, as a very important milestone in the history of ISRO, Nair said it will revolutionise DTH broadcasting and improve the entertainment scenario in the country.
INSAT-4A, the first satellite in the INSAT-4 series under which seven satellites have been planned, is equipped with 12 ku and 12 c band high-powered transponders, with a design life of 12 years.
ISRO officials in Bangalore said 12 ku band transponders provide around 140 to 150 DTH channels. The satellite is expected to be operational by the end of January.
INSAT-4A was originally planned for launch in the first half of 2005 but due to difficulties faced by Ariane and delay in the launch of first two satellites of other countries, the launch schedule was recast.
In the coming days, the MCF will conduct operations such as orbit raising manoeuvres to take the satellite into its final 36,000 km circular Geo-synchronous Orbit.
Deployment of solar antennas will be carried out before positioning the satellite in its designated slot of 83 degree East longitude, along with INSAT-2E and INSAT-3B.
MCF will also carry out regular operations and control the satellite during its service life, ISRO officials said.
Tata Sky has already signed an agreement with ISRO to lease all the 12 ku-band transponders to provide DTH transmission in India using VSATs.