Scientists at the Indian Space Research Organization (ISRO) are gearing up to launch five satellites by the end of this year, including the advanced remote-sensing Resourcesat-2 on April 20.
Resourcesat-2, along with Youthsat and X-SAT, will be launched by Polar Satellite Launch Vehicle PSLV-C16 from the Satish Dhawan Space Center at Sriharikota in the southern state of Andhra Pradesh. S. Satish, spokesman for the Bengaluru-based ISRO, tells Aviation Week that after facing initial hiccups, “the integration of all the three satellites to the launcher has been successfully accomplished.”
He says the Launch Authorization Board met last week to review the readiness of the launch vehicle, spacecraft systems and ground stations, and gave its approval for liftoff. “The launch will take place at 10:12 a.m. (IST) on April 20,” Satish says.
The primary payload, the ISRO-built Resourcesat-2, is an advanced remote-sensing satellite weighing 1,206 kg (2,660 lb.) that will be used to study and manage natural resources. The images taken will be useful for estimating the health of crops, locating ground water, keeping tabs on deforestation and monitoring water levels in reservoirs and lakes. Youthsat, weighing 92 kg, is a joint Indo-Russian satellite for stellar and atmospheric studies, including studying solar activity and its effect on the Earth’s upper atmosphere. X-SAT, weighing 106 kg, is a micro-satellite for imaging applications built by Nanyang Technological University in Singapore.
Satish says ISRO also is planning to launch two communication satellites — GSAT-8 onboard an Ariane rocket from Kourou, French Guiana, and GSAT-12 from India — by June to serve the needs of the telecommunication and television sectors. This would be followed by the launch of the Megha-Tropiques satellite, another GSAT and the Radar Imaging Satellite (Risat-1).
“With the launch of these satellites, ISRO is trying to wipe out the sad debacle of GSLV-D3,” Satish says. That mission failed to reach orbit last April, destroying the GSAT-4 satellite (Aerospace DAILY, July 12, 2010).
PSLV is ISRO’s most successful rocket. It can launch satellites in the 1-ton class (up to about 1,500 kg) into 600-1,000-km (370-620-mi.) orbits. This is sufficient for satellites meant for map-making, surveillance, remote sensing, etc. Communication satellites that need to be in a fixed position relative to India and the rotating Earth travel in geostationary orbit at about 36,000 km altitude. PSLV can take satellites to such orbits if the weight is only around 1,000 kg. In fact, it was used also for the Chandrayaan Moon mission.
For larger satellites such as the 2,000-kg Insat, ISRO developed the Geostationary Satellite Launch Vehicle (GSLV), which can send more than 2 metric tons into geostationary orbit. However, India’s reputation as a reliable space-launching country took a serious hit last year after the space research organization failed twice to launch satellites.
India began its space program in 1963, and has since designed, built and carried out multiple liftoffs. From 1994 to 2010, India’s Polar Satellite Launch Vehicle launched more than 50 satellites — more than half of them foreign. In October 2008, India launched its first unmanned Moon mission, Chandrayaan-1, to conduct experiments and search for evidence of water on the lunar surface. And last July, ISRO launched the Cartosat-2B satellite to facilitate urban planning and infrastructure development.
Mayank Vahia, scientist at the Mumbai-based Tata Institute of Fundamental Research (TIFR), says, “The satellite launch industry in India is cost-effective, reliable and consistent, which gives it a competitive edge over the rest of the world.” The cost of launching a satellite in India is 100 times less than that in the U.S.
Vahia adds: “India should be able to create a niche market by sharing its remote-sensing experience with countries who do not have proper capability and infrastructure to launch satellites.”
However, C.S. Unnikrishnan, another TIFR scientist, says that while the commercial market is OK for small satellites meant for mapping and remote sensing, the real global market is in larger, longer-living communication satellites that require reliable launchers in the GSLV class.
“This, ISRO [has] yet to demonstrate as fail-safe,” Unnikrishnan says. “They are working on it. They have some market share for smaller remote sensing-type satellite launches with PSLV, but most of the use is for home satellites. They are also working on a large GSLV [that] is supposed to be capable of taking 4,000 kilograms into geostationary orbit. If they demonstrate reliable GSLV performance in that class [2-4 metric tons], launch after launch, they can of course be market leaders. This will take time, perhaps a few years more.”