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Indian
Space Program
 In
India, the space program was formerly launched in 1972 with
the setting up of the Space Commission and the Department of
Space. Advancement in areas of communication, meteorology,
resources survey & management, develop satellites, launch
vehicles & associated ground systems were the initial
objectives. Since then, India has made impressive progress in
this field. Space technology has not only enhanced India's
communication capabilities, but has also contributed in
meteorological forecasting, providing advanced disaster
warning, search and rescue measures and distance education to
remote areas.
At the outset, one might ask "what is a satellite?." A
satellite is an object that revolves round a planet. For a
successful orbiting around the earth, it's essential for a
satellite to attain a speed of about 20,000 kms per hour.
Satellites are launched by very powerful rockets.
Space probes costs
enormously as the launching rockets cannot be recovered and
used again. The space-shuttle has emerged as a remedy to this
drawback. The main part of a space shuttle is an Orbiter, an
aircraft about the size of an air bus. It hovers into space
astride a large tank containing propellants to fuel the three
main engines of the craft. Two booster rockets are strapped
onto the tank; these rockets fire with the rift-off of the
Orbiter's engines and fall off on exhausting the fuels. They
are retained to be used again. The propellant tank is
jettisoned. The Orbiter is injected into orbit and after
carrying out its task, it retro-fires and descends back to
earth. Due to its wings, it is easily maneuvered through the
air and it lands on an ordinary runway.
From a historical perspective, the first Indian satellite was
Aryabhata, which was launched by a soviet rocket on 19th April
1975. This was launched from a cosmodrome near Moscow. It was
designed and built by Indian scientists and engineers of
Indian Space Research Organization. Orders and instructions
were transmitted to the experimental 360 kg satellite
Aryabhata from the control station at Sriharikota.
Bhaskara-I was the second Indian satellite & Bhaskara-II the
third which were launched from the same soviet cosmodrome
mainly for observations on the earth.
With the successful launch of SLV-3 on 18th July 1980 when a
35 kg satellite called Rohini I was placed in LEO, India
became only the seventh nation in the world to achieve space
orbit capability. This was the first time when a satellite was
launched from Indian soil. This was followed by the
development of SLV-3 D1, launched on May 31st 1981 injecting a
38kg Rohini-D1 satellite into an orbit near the earth. Its
life ended prematurely, nine days after the launch instead of
90 days as envisaged. The second development flight SLV-3 D
was launched on April 17, 1983 from the launch pad Sriharikota.
It put the 41.5 kg Rohini satellite RS-D2 into low earth
orbit. It carried a two-band solid state camera called 'smart
sensors' to take images of identification of landmarks for
orbit. It could also classify the ground features such as
water, vegetation, cloud and snow and helped in evaluating the
vehicles performance for future flights.
APPLE, which is an abbreviation of Ariane Passengers Payload
Experiment, was India's first geostationary telecommunication
satellite. It was shot into orbit on June 19, 1981 by European
Space Agency's Ariane rocket from Kourou in French Guyana.
Since 1982, a series of multi-purpose application satellites
like INSAT-1A, INSAT-1B, INSAT-1C and INSAT-1D have been
launched. INSAT-1B and INSAT-1C are geostationary satellites.
Nowadays, INSAT-1B is used extensively for weather
forecasting. INSAT-1B is also used to receive and retransmit
telephone calls. The telecommunication and mass communication
capabilities of the INSAT system, which is linked with the
International Telecommunication satellite (INTELSAT), is being
used by the Oil & Natural Gas Commission (ONGC), the Indian
Post & Telegraph Department with 28 fixed and 3 transportable
stations, Doordarshan, Indian Meteorological Department, All
India Radio etc.
India's first operational Earth Observation satellite IRS- 1A,
a 850 kg satellite was launched into a 900 km polar orbit on
17th March 1988 by a Soviet rocket. In 1997, India used its
own rocket PSLV to place IRS-1D into polar orbit. With the
development of PSLV, India has the capability to place up to
1,200 kg satellites into polar orbit.
For near atmosphere weather scanning and forecasting, the
Rohini and Menoka series was developed by the Vikram Sarabhai
Space Center (VSSC) at Thumba near Trivandrum. Till date,
nearly 1500 rockets have been launched from Thumba, Balasore
and Sriharikota ranges for space technology studies. VSSC at
Trivandrum, the largest ISRO center, has various chemical,
mechanical and electronic facilities for development,
production and testing. The major units found here are Space
Science and Technology Center (SSTC), Rocket Fabrication
Facility (RFF), Rocket Propellant Plant, Propellant Fuel
Complex (PFC), Thumba Equatorial Rocket Launching Station (TERLS),
Ammonium Perchlorate Experimental Plant (APEP) & Reinforced
Plastic Center (Replace).
The principal rocket & satellite testing and launching station
is SHAR in Sriharikota island in Andhra Pradesh. The ISRO
satellite center in Bangalore has the primary responsibility
for planning, design, development, fabrication, integration,
test and qualification of satellites. The primary tasks of the
Space Application Center at Ahmedabad are to conceptualize,
plan and execute projects. National Remote Sensing Agency at
Secunderabad, an autonomous registered society supported by
Department of Space, utilizes modern remote sensing techniques
for planning and management of the country's natural resources
and provides operational support for various users. The
experimental data of NRSA finds application in many fields
such as land use, pollution monitoring, soil classification,
cartography, geological and geographical survey, oceanography,
agriculture, etc.
Other institutes working in this area includes Physical
Research Laboratory (PRL) at Ahmedabad which conducts basic
research in space sciences. The Master Control Facility at
Hassan in Karnataka is a tracking station for launching
satellites.
Satellite technology have strengthened existing telegraphy,
telephony, wireless telegraphy and also radio communication.
Bio-prospecting in India is becoming a lot easier, with
satellites helping Indian scientists reap nature's benefits.
Scientists are using the Indian Remote Sensing (IRS)
satellites to map vegetation, ecological zones and landscapes
to provide valuable information that biologists could use in
their hunt for new resources. Researchers from more than a
dozen institutes have teamed up for the research project
supported by the Department of Biotechnology (DBT) and the
Department of Space (DOS).
There is a growing global interests in plants as potential
sources of undiscovered drugs. "Satellite remote sensing will
provide a tremendous boost to bio-prospecting," says Manju
Sharma, DBT Secretary. "It will help speed up the search for
novel biological resources. And speed is crucial in the
increasingly competitive field of bio-prospecting."
Scientists involved in the DBT-DOS project are using IRS
satellites to map India's richest zones of biological
diversity, the eastern and western Himalayas and the Western
Ghats. They're among the world's top 20 areas teeming with a
rich diversity of plants and animals.
DOS researchers with the National Remote Sensing Agency have
already mapped an important plant called Taxus in the Tale
Valley of Arunachal Pradesh using satellite images. Taxus is
the source of an important cancer fighting chemical called
Taxol. With the help of satellite imagery, IHBT scientists
hope to search for elite varieties of Taxus in the forest of
Arunachal Pradesh.
Remote sensing specialists also plan to use satellite imagery
to map regions where another plant called 'Hippophae,' which
is one of the richest known sources of Vitamin C. Several
countries are already exploiting this plant for its vitamin
and oil content. The landscape map generated by satellite
imagery will help in locating appropriate places where special
varieties of 'Taxus' or 'Hippophae' could be cultivated.
Scientists have already completed vegetation maps for five
states in the North East region and three districts of
Karnataka and Maharashtra. By analyzing maps of the same
region over time researchers hope to evaluate threat to
biodiversity caused by human activity.
There're several botanical and agricultural research centers
participating in the bio-prospecting program. The images
beamed down by the IRS satellite will be processed by the
Scientists at the Indian Institute of Remote Sensing at
Dehradun and the National Remote Sensing Agency at Hyderabad.
There have been hiccups along the way. Recently i.e. on 6th
Nov, 2000 payload operations of the multipurpose satellite
INSAT 2B were switched off following erratic functioning after
it was retrieved from loss of earth lock. ISRO said it has
abandoned Insat-2B. Yet it claims there would be little impact
on the telecommunications, broadcast and meteorological
sectors it supported. "Most of the services have been taken
out. So for all practical purposes, from the service point of
view, the satellite has been decommissioned," ISRO chairman
K.Kasturirangan told a news conference in Bangalore. He said
the impact of decommissioning Insat-2B will be minimal because
all telecommunications and most broadcast services had already
been moved to other INSAT satellites and one Thaicom
satellite.
– Subhajit
Ghosh
November 16, 2000
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