With a population of more than 1 billion people, India has been targeted as one of the largest potential markets for satellite services, but the Indian Space Research Organization‘s (ISRO) efforts to play a key role in developing the market have been thrown into chaos after the failed launch of the Insat-4C satellite July 11, India’s heaviest ever communications satellite.

The Geosynchronous Satellite Launch Vehicle (GSLV) carrying the spacecraft veered off course shortly after being launched from the Sriharikota Space Research Centre and was destroyed, along with the Insat-4C and its 12 Ku-band transponders designed to provide direct-to-home (DTH) TV services, video picture transmission, digital satellite news gathering (DSNG) and to serve the National Informatics Centre with VSAT connectivity. The satellite weighed 2,168 kilograms and was designed to operate for 10 years.

The challenge for ISRO is what to do next.

Madhaven Nair, chairman of ISRO, said the loss of Insat-4C capacity would "only have a short-term impact. Insat-4C was to have provided 12 Ku-band transponders. The Insat system already has 175 transponders, and this includes some in-orbit spares, which can be used to meet a portion of the user requirements booked on Insat-4C. In addition, ISRO had already scheduled a series of Insat/GSAT satellites, which will carry 24 high-power Ku-band transponders in the near future. With the launching of these satellites, ISRO is confident of meeting the requirements of the Indian users in a timely manner. Whenever there is a temporary shortfall in capacity, ISRO also exercises the option of leasing capacity from other satellite operators and making it available to customers until capacity from Indian built satellites becomes available."

While the loss of Insat-4C dealt a blow to ISRO’s plans, the organization is moving ahead on launching on other satellites, Nair said. "In the year ahead, India will continue to launch communication and remote sensing satellites to enhance the present system capabilities," he said. "Insat-4B, identical to the Insat-4A satellite, which was launched in December 2005, carrying 12 Ku-band and 12 C-band transponders mainly catering to direct-to-home television services, is planned for launch on board a European Ariane launcher in the first quarter of 2007. An experimental satellite, GSAT-4, to demonstrate multi-beam Ka-band transponder and carrying a navigation payload, besides several spacecraft bus technologies, is planned for launch on board our GSLV."

While ISRO is still investigating the most July GSLV failure, the agency also is pushing ahead with upgrades to the vehicle designed to increase its payload capacity, Nair said. "While the present GSLV carrying the Russian supplied cryogenic stage is able to launch 2,000 kg-size satellites into [geosynchronous transfer orbit], once the Russian supplied cryogenic stage is replaced by India’s own cryogenic stage, which is now in an advanced stage of testing, GSLV will be able to place up to 2,500 Kg-size satellites in" geosynchronous transfer orbit, he said.

Launch Vehicle Plans

The next-generation vehicle, dubbed GSLV-Mk 3, will be able to place up to 4 tons into geosynchronous orbit, Nair said. The first test of that vehicle is scheduled to take place in 2008.

The agency’s smaller rocket, the Polar Satellite Launch Vehicle (PSLV), has completed eight missions, and Nair describes it as "the workhorse launch vehicle" for India. "It has launched not only remote sensing satellites into polar orbits, but also, has launched a meteorological satellite, Kalpana-1, into geosynchronous transfer orbit. Besides, it has successfully demonstrated multiple satellite launch capability having already launched three satellites simultaneously in two of its missions. PSLV is planned to be used in the launch of Chandrayaan-1 spacecraft. PSLV is a reliable and versatile launch vehicle for low-Earth orbit, polar and even for launching small satellites into [geosynchronous transfer orbit]. This vehicle is already being offered to international customers and there are few satellites lined up for launch — Italian Agile and a satellite from Singapore."

If everything remains on schedule, ISRO is entering a busy period, and the organization also expects to make progress in the remote sensing area. The Cartosat-2 imagery satellite, which will carry a black-and-white camera capable of collecting images with 1-meter resolution, is scheduled to be placed into orbit by a PSLV before the end of the year. Another PSLV mission is slated to carry a Space-capsule Recovery Experiment (SRE) to demonstrate recovery of an orbiting space capsule as well as a small Indonesian satellite.

ISRO also is looking at the key milestone of flying its first successful mission to the moon. Nair said, "Substantial progress is expected in realizing India’s first mission to moon, Chandrayaan-1, to be launched in the first quarter of 2008."

Benefiting India

Nair believes the work the organization has done has "brought a sea change in several sectors of national development" and improved telecoms, business communications and direct-to-home services. "Several social applications have been undertaken to benefit the society at the grass roots level," he said. "For example, Edusat has helped networking of educational institutions and to transmit lessons to rural students. Insat based telemedicine network connects 134 rural and remote area hospitals to 32 super specialty hospitals in major cities thus taking super specialty medical consultations to populations in remote and inaccessible regions. There is a vast improvement in weather forecasting due to the cloud cover pictures sent in by Insat satellites as well as the meteorological data collection platforms across the country. This has also been used to issue warning on approaching cyclones."

Remote sensing is also playing an integral role, Nair said. "Several applications like ground water prospecting, agricultural acreage and yield estimation, land use and land cover planning, forecasting potential zones for fishing, forest survey, etc, have been taken up. Remote sensing is also used in disaster mitigation by mapping flood inundated areas, locating forest fires, etc. Combining the capabilities of Insat and IRS satellites, several Village Resources Centres have been set up to help farmers by providing information on various aspects like land, crop, market information, weather forecasts, and providing connectivity for telemedicine."

–Mark Holmes Contact, S Krishnamurthy, ISRO, e-mail, [email protected]