INSAT-3C – Another feather in ISRO’S Cap T V Padma (Science Journalist)
Agni Surface to Surface Missile The mission objectives were fully met as confirmed by data from the network of ground radars, telemetry stations and visual observations from the Naval ships positioned near the intended impact point.
The launch was witnessed by Shri George Fernandes, Defence Minsiter, Chief of the Air Staff, Air Chief Marshal S Krishnaswamy, Dr. V.K. Aatre, Scientific Adviser to Defence Minister and other senior officers from the Armed Forces and DRDO. The Defence Minister congratulated the scientists and staff of DRDO and other partners. He expressed his happiness that the mission was flawless and enhanced India’s capability in deployment of such surface-surface missile systems.
INSAT-3C – Another feather in ISRO’S Cap
T V Padma (Science Journalist)
India has crossed another milestone in its space programme with the launch of the Indian National Satellite INSAT-3C. The satellite was launched by the Ariane-4 rocket on January 22, 2002 from the spaceport of Kourou in French
Guyana.INSAT-3C is to carry 24 C-band transponders, six extended C-band transponders, two S-band broadcast satellite service transponders and mobile satellite service (MSS) transponders.Once commissioned, the satellite will further increase the present INSAT capacity in telecommunications. It is positioned at 74 degrees East longitude in a circular geosynchronous orbit
36,0000 kms above the earth. Its movement will be synchronized with that of the earth.INSAT-3C is a communications satellite and a replacement for INSAT-2C whose life ends by the end of 2002. Besides providing continuity to INSAT-2C’s telecom services, it will also augment the KU-band capacity of its predecessor INSAT-3B. It joins two more of its operating companions – INSAT-2E and INSAT-3B in space.
INSAT-3C was originally scheduled for launch by Arianespace’s new and more powerful Ariane-5 rocket. However, the failure of one of the Ariane 5 rockets in 2001 led to the delay in all subsequent launches and Arianespace rescheduled INSAT-3C for an exclusive launch aboard Ariane 4 in January 2002, an Indian Space Research Organisation spokesman said.
The satellite will weigh 2650 kg at lift-off, carrying 1432 kg of propellant. Its dry mass will be 1218 kg, without the fuel. Its main body is a cuboid of 2 metres X 1.77 metres X 2.8 metres size. When fully deployed with an antennae and a solar panel on each side, it will measure 15.44 meters from one solar panel to the other. The length from one antenna to the other will be 7.8
metres.The sun-tracking solar panels will generate a power of 1765 watts. The Ariane rocket will initially put INSAT-3C into a
geosynchronous elliptical transfer orbit with a perigee of 560 kms and apogee of 35,865 kms. From this position, it will be
raised to a geosynchronous circular orbit of about 36,000 kms by firing the liquid motor on board the satellite. The INSAT Master Control Facility (MCF) at Hassan in Karnataka will take control of INSAT3C soon after its injection into orbit by Ariane and will carry out all orbit manoeuvres, deployment of solar panels, payload checks and in-orbit operation of the
satellite.Background
The latest satellite launch adds yet another feather to ISRO’s cap. Indian space scientists have travelled a long way since the beginning of their well-orchestrated space programme that began four decades ago. ISRO made a modest beginning in 1963 when it launched a small sounding rocket from Thumba near Thiruvananthapuram. It then went through an experimental and
demonstration phase in the 70s when India conducted large-scale experiments like Satellite Instructional Television Experiment (SITE) and Satellite Telecommunications Experiment (STEP).During this period, India also undertook demonstration of space applications for communication, broadcasting and remote sensing; designing and building experimental satellites such as Aryabhatta, Bhaskara, APPLE and Rohini. Alongside, it began designing and building on launch vehicles.These small Indian satellites and rockets were the forerunners of the more powerful, sophisticated and complex satellites and satellite launch vehicles or rockets that were commissioned in the 80s and today form part of the ambitious Indian space programme.The initial experimental satellites laid the foundation for the Indian National Satellite (INSAT) system, one of the largest domestic communications satellite systems in the world. INSAT, commissioned in 1983, is a multipurpose satellite system for telecommunications, television broadcasting, meteorology and search and rescue.
The INSAT system has vastly improved telecommunications, television broadcasting, radio networking, meteorology and disaster management services. Besides telecommunication and other regular broadcasting services, INSAT is widely used for interactive educational television in rural areas. INSAT satellites have also helped harness space technology for grass root level applications – for example, the Jhabua Development Communication Project (JDCP) that started in November 1996, the extensive Training and
Development Communication Channel (TDCC) of INSAT and the Vidya Vahini programme for education and training in remote rural areas with INSAT3B. INSAT’s meteorological imaging capability and direct-to-community broadcast capability help in issuing warnings on impending cyclones which help in timely evacuation of people from coastal areas likely to be affected. INSAT also carries transponders for search and rescue operations.The country has had three generations of INSAT satellites – INSAT1, INSAT2 and INSAT3. The first generation INSAT-1 series was designed by ISRO for telecommunications, broadcasting, weather monitoring and disaster warning services and built by Ford Aerospace of the United States. Of these, INSAT-1A and INSAT1C could not complete their mission.
INSAT1 satellites carried 12 C-band telecom transponders, two high-power S-band television broadcast transponders and Very High Resolution Radiometer (VHRR) transponder for meteorological earth imaging, and a data relay transponder for relay of meteorological, hydrological and ocean data.
Capability
But in a major leap in indigenisation, ISRO designed and built on its own its second-generation heavier INSAT-2 series of satellites weighing over 2000 kg. In addition to the transponders on the INSAT system, INSAT2 satellites carried six extended C-band telecom transponders, and a transponder for search and rescue operations. Additionally, INSAT-2C carried three
Ku-band transponders and one CXS band transponder for mobile satellite services. Of these, INSAT-2D became inoperable because of a short circuit in one of the power lines of the spacecraft. INSAT-2E is in operation with 11 of its transponders leased to the International Telecommunications Satellite Organisation INTELSAT.The third generation INSAT3 series is now on the way. The first of these, INSAT-3B was launched in March 2000. Next
week’s INSAT3C marks the second in this series.The IRS series of satellites is considered the world’s best civilian remote sensing satellites. Remote sensing data from these satellites are being used for estimating agricultural crop acreage and yields, ground water location, forest cover survey, wasteland mapping for possible reclamation, snow melt run-off estimates, mineral prospecting, identification of potential fishing zones, urban planning and environment monitoring.India’s capability to build and operate world-class remote sensing satellites has brought in commercial benefits for it. Data from IRS satellites are now being sold to several countries including USA, European nations, Japan, Korea, Thailand and Middle East countries.
India matched its strides in satellite technology with similar advances in satellite launch vehicle technology. The sounding rocket from Thumba helped ISRO scientists design the Satellite Launch Vehicle (SLV) to place small 40-kg satellites in orbit. This was followed by the Augmented Satellite Launch Vehicle (ASLV) to launch 150-kg satellites into space. ASLV paved the way for the four-stage Polar Satellite Launch Vehicle (PSLV) to launch 1000-kg IRS satellites and last year’s GSLV to launch 2000-kg INSAT class satellites.(keralamonitor.com)
