ORGANISATION AND
FACILITIES
1.
ORGANISATION OF SPACE
RESEARCH
1.1 Indian National
Committee for Space Research
(INCOSPAR):
INCOSPAR is one of the committees of the Indian National Science Academy
(INSA) which is the national adhering organisation to the International Council
of Scientific Unions (ICSU) and a member of ICSU Council. Prof. G.S. Agarwal is
the present Chairman of INCOSPAR which has the following terms of
reference:
(i) to recommend and
promote national activities and international co-operation in space exploration
and space research.
(ii) to provide
necessary liaison with the Committee on Space Research (COSPAR) of ICSU, and
encourage participation in international activities which contribute to the
peaceful uses of outer space.
1.2 Space Commission,
Department of Space and Indian Space Research
Organisation:
The Space Commission and the Department of Space (DOS) were established
by the Government of India in 1972 to promote development and application of
space science and technology for identified national socio-economic objectives.
The Space Commission lays down the framework of important space activities and
advises the Government on major policies related to India’s space programme. DOS
functions directly under the Prime Minister of India. Dr.K.Kasturirangan is the
present Chairman of the Space Commission, Secretary to the Government of India
in DOS and Chairman of the Indian Space Research Organisation
(ISRO).
The Indian Space Programme is directed towards the goal of self-reliant
use of space science and technology for national development, its main thrusts
being: (i) satellite telecommunications, TV and radio broadcasting (ii)
satellite remote sensing for resource survey and management, environmental
monitoring and meteorological services, and (iii) development and
operationalisation of indigenous satellites and launch vehicles for providing
these services.
DOS is responsible for carrying out space research and related activities
in the country through ISRO’s constituent units and three major autonomous
institutions namely, National Remote Sensing Agency (NRSA), Physical Research
Laboratory (PRL) and National MST Radar Facility (NMRF). DOS is also the nodal
department for implementation of the ongoing National Natural Resources
Management System (NNRMS). As the research and development wing of DOS, ISRO is
responsible for the overall implementation, execution and future projections
related to the country’s space programme and acts as the sponsoring agency for
participation of Indian scientists in collaborative space research programmes
with foreign space agencies. The activities of space science research,
development of space technology for applications in the areas of communications,
remote sensing and meteorology are implemented by ISRO through its various
Centres/Units. The overall planning and co-ordination of the programme is
directed from the DOS and ISRO Headquarters situated at Bangalore. Following are
the major establishments of DOS carrying out research and development activities
under the space programme.
·
Vikram
Sarabhai Space Centre (VSSC),
Thiruvananthapuram
·
ISRO
Satallite Centre (ISAC), Bangalore
·
Space
Applications Centre (SAC), Ahmedabad
·
Satish Dhawan Space Centre, SHAR, Sriharikota, Andhra Pradesh
· Liquid
Propulsion Systems Centre (LPSC) with its facilities at Bangalore,
Thiruvananthapuram and Mahendragiri
·
Physical
Research Laboratory (PRL), Ahmedabad
·
National
Remote Sensing Agency (NRSA),
Hyderabad
·
National
MST Radra Facility (NMRF), Gadanki
·
Indian
Institute of Remote Sensing (IIRS), Dehra
Dun
·
Development
and Educational Communication Unit (DECU),
Ahmedabad
· ISRO
Telemetry, Tracking and Command Network (ISTRAC) with its stations at Bangalore,
Lucknow, Sirharikota, Port Blair and
Mauritius
·
ISRO
Inertial System Unit (IISU),
Thiruvananthapuram
·
INSAT
Master Control Facility (MCF), Hassan,
Karnataka
The Antrix Corporation Limited, Bangalore established in 1992, is a
wholly owned Government of India company for marketing space products and
services. Various programme offices in different areas function as a part of the
Central Management at ISRO HQ/DOS, Bangalore. ISRO’s sponsored research
programme (RESPOND), Technology Transfer and Utilisation, NNRMS, Regional Remote
Sensing Service Centres (RRSSC) and space science research activities including
balloon, rocket and satellite experiments, multi-agency sponsored projects in the area of space sciences
are all co-ordinated from ISRO HQ. ISRO’s Advisory Committee for Space Sciences
(ADCOS) represented by space
scientists of the country, recommends the conduct of various space science
research activities and advises ISRO on the long term planning and promotion of
space science research in the country. The detailed co-ordination and
implementation of the space science programmes are assigned through the Space
Science Office at ISRO HQ which also manages the functions of the Space Science
Data Centre (SSDC) at Bangalore.
1.3 Research
sponsored by ISRO (RESPOND):
Apart from the in-house research and development activities and
co-ordination of various national level space science projects, ISRO has a
sponsored research programme called RESPOND aimed at providing financial
assistance to research and development projects relevant to the Indian space
programme at the universities and academic/research institutions in India.
RESPOND promotes research and educational activities in space sciences and
related subjects at academic levels and strives for closer interaction between
the scientific and engineering staff of ISRO and the academicians of
universities. The RESPOND support to reseach projects is provided to cover expenses
of research fellowships, special equipment, components, travel etc. Since its
inception in 1976, a large number of projects have been funded in more than 100
institutions/ universities. Based on the experience of operating the RESPOND
projects at different institutions, a few space technology cells (STC) have been
established at premier academic institutions and universities to carry out
advanced technology research programmes which can be undertaken jointly with
ISRO.
1.4 Centres for Space
Science Research in India:
Although ISRO is the prime organisation entrusted with the responsibility
of executing the overall space programme of the country, the space science
research is being undertaken at large number of universities, research
institutions and often promoted and jointly sponsored by agencies outside ISRO.
Within ISRO system, space science research is being carried out at Physical
Research Laboratory (PRL), Udaipur Solar Observatory (USO), Space Physics Laboratory (SPL) of Vikram
Sarabhai Space Centre (VSSC), Technical Physics Division of ISRO Satellite
Centre. (ISAC) and at the National MST radar Facility (NMRF). A list of the
institutions currently involved in space science research is given in the table
at the end of the report. In addition to supporting the space science research
activities at its own units mentioned above, and at various academic and
research institutions outside through its RESPOND programme, ISRO also initiates
and promotes space scienece research activities in the country through its ADCOS
system.
2. HIGHLIGHTS OF SPACE RESEARCH ACTIVITIES
DURING THE YEARS 1998 & 1999
Some of the important developments of Indian space programme during the
period are highlighted below:
2.1 Indian Remote
Sensing Satellites (IRS):
Indian Remote Sensing satellite (IRS) system, now comprising of five
satellites, IRS-1B, IRS-1C, IRS-1D, IRS-P3 and IRS-P4 (OCEANSAT), forms the
largest constellation of remote sensing satellites in the world offering a
variety of data in different spectral bands and various spatial resolutions. The
successful launch of PSLV-C2 on May 26, 1999 from Satish Dhawan Space Centre, SHAR, Sriharikota, putting
into orbit for the first time three satellites simultaneously – IRS-P4, KITSAT-3
of Republic of Korea and DLR-TUBSAT of Germany is a significant achievement.
OCEANSAT has opened up new vistas for ocean remote sensing. The Ocean Colour
Monitor (OCM) on board the satellite provides data on chlorophyll concentration,
phytoplankton, atmospheric aerosols and suspended sediments in water. The other
instrument, Multifrequency Scanning Microwave Radiometer (MSMR), provides data
related to sea surface temperature, wind speed, cloud water content in the
atmosphere.
2.2 Indian National
Satellite (INSAT):
INSAT system is
one of the largest domestic satellite communication system in the world today
comprising of four satellites, INSAT- 2B, INSAT- 2C, INSAT -2E and INSAT
-2DT. INSAT-2E, the last satellite
of the second generation INSAT–2 series, launched on April 3, 1999, is the most
advanced satellite built by India so far. The satellite is providing the
intended telecommunication and television services as well as meteorological
imaging from its high resolution Charge Coupled Device (CCD) camera in addition
to the regular Very High Resolution Radiometer (VHRR) in visible and IR bands
and the water vapour channel. Besides providing telecommunication and television
services, a channel of INSAT is being used for satellite based training and
developmental communication.
2.3 Stretched Rohini
Satellite Series-C (SROSS-C):
The satellite SROSS-C2 weighing about 113 kg and successfully launched on
May 4, 1994 by ASLV-D4 carries two scientific payloads consisting of
scintillation detectors for measuring cosmic gamma-ray bursts and retarding
potential analysers for measuring electron/ion densities and temperatures in the
F-region ionosphere. Both the experiments are functioning well and providing
valuable data.
Retarding
Potential Analyser (RPA) aeronomy payloads of Electron and Ion RPAs have
completed 7 years of successful operation in the orbit. The Electron and Ion
RPAs have yielded excellent quality of ionospheric plasma data set related to
F-region ionospheric electron and ion temperatures, total ion densities,
irregularity structures in electron and ion densities, composition of positive
ions and supra-thermal electron flux upto 30 eV along the satellite orbit over
the Indian region covering the equatorial and low latitudes. Having operated the
RPA payloads for data collection normally during two orbits a day, so far data
for more than 4400 orbits has been collected during past 7 years over the Indian
region. This period covers the periods of minimum solar activity in 1996 to peak
of high solar activity presently going on thereby covering the full solar
activity. Apart from regular data collection, some coordinated campaigns with
MST radar, Leonid Meteor Shower events, satellite beacon observations and
Ionsonde were also organised.
The raw data from the satellite is
received at the ISRO telemetry station and then processed at NPL, New Delhi for
its scientific usage. NPL along with seven universities are involved in
scientific analysis of the RPA data.
2.4 National Natural
Resources Management System
(NNRMS):
NNRMS functions with DOS as the nodal agency and with the active
participation of various State and Central Departments/Agencies. The
availability of data from IRS satellites on a continuous and assured basis
has enabled taking up a number of nation-wide remote sensing application
projects. Integrated Mission for Sustainable Development (IMSD) initiated
in 1992 has been launched in 174 districts of the country aimed at generation of
locale-specific prescription for development at micro
level.
2.5 National
Mesosphere-Stratosphere-Troposphere (MST) Radar Facility
(NMRF):
An ultra-sensitive MST radar
operating at 53 MHz has been established as a national facility at Gadanki
(13.5oN, 79.2oE) near Tirupati, India. This radar is
capable of high resolution mapping of atmospheric turbulence and vector wind
fields. As the radar is located at a low latitude station in tropical region of
India it provides a vital link in the currently operating global network of such
MST Radars.
The radar was
commissioned for scientific experiments in March 1994. It has successfully
completed four years of operation. A number of experiments have been carried out
by the user scientists from various R&D institutions and universities
covering a wide range of problems in atmospheric dynamics, coupling processes as
well as ionospheric irregularities.
To fill up the
gaps in the lower troposphere (< 4 km) and in the 25-60 km height regions,
two new facilities viz. Lower Atmospheric Wind Profiler (LAWP) and a
Mie/Rayleigh Lidar have been installed at NMRF in collaboration with
Communication Research Laboratory (CRL), Japan. The LAWP and LIDAR systems were
commissioned during September 1997 and April 1998 respectively. The LAWP is an
ideal system for studies of boundary layer which falls in the near field region
and hence not covered effectively by the MST radar. The Lidar also complements
the MST radar observations by providing information on aerosol concentrations
between 10-30km and on temperatures above
30km.
The development
of a new signal and data processing system for the MST radar is in progress to
enhance the data acquisition and on-line processing capabilities of Indian MST
Radar and also to extend the radar operations to incoherent back-scatter
mode.
NMRF, Sri Venkateswara University (SVU), Tirupati and ISRO organised the
8th International Workshop in Technical and Scientific aspects of MST radar
(mst8) at Bangalore. This workshop was preceded by a School on Atmospheric Radar
(SAR) which was held at SVU and at NMRF, Gadanki. A total of 130 scientists and
engineers, 52 of them from 17 countries outside India, participated in mst8. An
international steering group consisting of S. Fukao, M.F. Larsen, C. H. Liu, A.
P. Mitra and J. Roettger, with the latter as chairman, guided the formulation of
workshop programme. The proceedings of mst8 have been published as a special
issue of Solar Terrestrial Energy Programme (STEP)
Handbook.
The
successful launch of IXAE payload onboard the Indian satellite IRS-P3 by PSLV
from Shriharikota range on March 21, 1996 is a landmark event in the history of
experimental high energy astrophysics in India. The payload consists of (a) 3
pointed mode proportional counters (PPC) and (b) an X-ray sky monitor (XSM). The
PPCs are gas filled (Argon/methane) operating in the energy range 2-20 keV with
a narrow FOV of 2.3°x2.3°.
IRS-P3 is a sun synchronous satellite placed in a polar orbit of about 830 km.
The satellite has a unique combination of sensors for remote sensing of the
earth resources and X-ray astronomy and it is operated in both earth and stellar
pointing modes. The PPCs are 3 layers of multi-wire proportional counters each
having 18 cells with veto layer. Charged particles are rejected electronically
by means of mutual anti-coincidence. The X-ray Sky Monitor (XSM) is a pin-hole
camera of 1 cm2 hole placed over one dimensional position sensitive
proportional counter with FOV 90°x90°operating
in the energy range 2-10 keV. A number of X-ray binary stars including Cyg X-1,
GRS 1915+105 and Vela X-1 have been observed by IXAE. Cyg X-1 source has been
observed in detail by computing its Power Density Spectrum (PDS) showing the
hard and the soft states. During soft state (high state) the intensity of source
almost doubles. The temporal variations of milliseconds to minutes are also
observed characteristics of black hole binaries. Observations of GRS 1915+105
showed QPOs with a frequency of 0.72 Hz and intensity variations by a factor of
2 to 3 within 100ms. More
observational data being analysed using IXAF experiment would help in
understanding a number of problems in contemporary astrophysics and
cosmology.
The Advisory Committee for Space Science (ADCOS) has been reconstituted
with the formation of two sub-committees (ADCOS-1 and ADCOS-2) responsible for
specific areas of space science research programmes. Several meetings of these committees have been
held to review space science and
related activities conducted so far and to discuss future projects. A
number of recommendations on undertaking space borne missions on high energy
astronomy, climate variability and planetary science/exploration have been made
for the consideration of support by
ISRO.
The observational period of Indian Solar Terrestrial Energy Programme
(I-STEP) as formulated by five scientific working groups has been completed. An
extensive campaign on equatorial sporadic layer and electrojet has been carried
out with multiparameter ground based measurements from different Indian
stations. Interesting events on successive occurrence of counter electrojet and
blanketing sporadic-E have been observed. Besides Department of Space, the
programme has the participation and sponsorship of Department of Science and
Technology (nodal agency), Council of Scientific and Industrial Research and
University Grants Commission.
2.9 INDOEX
Indian Ocean
Experiment (INDOEX), the multi-agency programme with DOS as the nodal agency has
successfully completed two field campaigns mainly consisting of ship borne
experiments/observations. The programme has provided valuable insight/inputs
towards understanding of climate and monsoon besides aerosol characterisation
over the Indian Ocean region. INDOEX India programme has been reviewed and the
scientific achievements consolidated. Indian participation in INDOEX is jointly
sponsored by DOD, DOE, DOS, DST and CSIR with DOS as the nodal
agency.
3. FACILITIES FOR SPACE SCIENCE
RESEARCH
The Indian Space Research Organisation (ISRO) has necessary expertise and
facilities for development, fabrication and testing of payloads for scientific
experiments onboard Indian Satellites. These facilities are available to Indian
scientists in other laboratories and organisations desirous of performing space
science experiments. Rocket and balloon payloads for space science experiments
have been developed and fabricated at ISRO, NPL, PRL, TIFR, CESS, Gujarat and
Poona Universities. The payload integration and test facilities and the launch
of sounding rockets are provided by ISRO. The payload integration and launch for
balloon experiments are carried out from national balloon facility at Hyderabad.
Satellite payloads relevant to space science research have been designed and
developed at NPL, SAC, TIFR, PRL and
ISAC.
3.1 Thumba Equatorial Rocket Launching
Station (TERLS):
TERLS, now a unit of Satish Dhawan Space Centre, SHAR was established as a UN sponsored
Sounding Rocket Range in 1963, and is situated near Thiruvananthapuram city on
the coast of Arabian Sea. The magnetic equator passes very close to Thumba
(9oN, 77oE). The location of Thumba offers unique
advantages for low latitude upper atmospheric and ionospheric studies which
are of special importance in the region of magnetic equator. The range at
present has capabilities of launching meteorological and medium sized sounding
rockets for climatological, geophysical and astronomical studies. The range of
rockets include RH-200, RH-300 MKII and RH-560 MKII. Apart from India,
scientists from France, Germany, Japan, USA and USSR (Russia) have participated
in many scientific experiments using rockets from this
range.
3.2 Sriharikota Rocket Launching Station
(SHAR):
SHAR (13oN, 80oE) is located on the east coast of
the country about 100 km north of Chennai city. It has facilities to launch
large multistage sounding rockets capable of probing the F-region of the
ionosphere. Necessary facilities for launching satellites have also been
established here.
3.3
Balasore Rocket
Launching Station (BRLS):
This facility for launching indigenous meteorological rockets of
200mm diameter was set up at Balasore (21oN,87oE) in
Orissa state on the east coast of India primarily to meet the requirement
of international MONEX-79 campaign. The facility is operational since January
1979 and synoptic meteorological rocket launches have been continued till March,
1995 with funding contributions from the Department of Science and Technology
(DST), Council of Scientific and Industrial Research (CSIR) and ISRO. The
rocket launching station can be operated for meteorological rocket soundings in
campaign mode if such a need arises.
3.4
National Balloon
Facility:
The TIFR-ISRO National Scientific Balloon Facility at Hyderabad
(18oN, 79oE) is a premier centre in the country to carry
out research in space astronomy and atmospheric sciences. It undertakes and
caters to all aspects of scientific ballooning, namely, the balloon engineering,
balloon design and fabrication, radio telemetry, telecommand, flight
instrumentation, the balloon launch and all the related research and development
including the development of a special balloon grade polythelene film. This
facility is funded by the Department of Atomic Energy (DAE) and Department of
Space (DOS).
In the area of balloon fabrication, a Reefing Sleeve has been included in
all the balloons made at TNSBF. Reefing sleeves prevent the undeployed portion
of the balloon from spreading out and thus adds to the safety of the balloon in
flight. The balloon launch vehicle is built around a turbo charged twin axle 25
tonne Leyland truck. In the area of balloon support instrumentation, a
microprocessor based PCM telemetry decoder, a PC based on-line telemetry
decoding and data analysis system have been implemented. The real-time telemetry
data is stored on hard disks.
3.5
Magnetic Observatories:
The Magnetic Observatories operated by Indian Institute of Geomagnetism
(IIG) are located at Thiruvanathapuram, Annamalainagar, Pondicherry, Alibag,
Nagpur, Ujjain, Shillong, Gulmarg and Vishakapatnam. The INTERMAGNET unit at
Alibag provides 1 minute data in the three components H, Z, D for the real time
monitoring of the magnetospheric ring currents. These are sent regularly to
National Geomagnetic Information Centre,
USA.
Indian magnetic data are regularly published as processed hourly values,
after incorporating all the corrections. Quarterly prompt magnetic data report,
depicting equatorial electrojet strength is prepared and supplied to interested
scientists and institutions.
The World Digital Data Centre (WDC-C2) operates from IIG, Mumbai. The
data centre is equipped with terminals and PCs to promote effective use of the
data by users. Software routines for analysis of the data have been developed
and hardware back up for data storage and retrieval are augmented through the
introduction of CD-ROM reader and scanner.
3.6 Decametre Wave Radio
Telescope:
The Raman Research Institute, Bangalore, in collaboration with the Indian
Institute of Astrophysics, Bangalore, operates a decametre wave radio telescope
at Gouribidanur (14oN) near Bangalore. The array is made up of
1000 dipoles oriented in the east-west direction and arranged in the form of the
letter "T" with a 1.4km arm and 0.45km southern arm. The array operates at a
central frequency of 34.5 MHz and has an effective collecting area of
around 20,000 m2. The beam can be steered electronically in the
north-south direction by ±45o and the half power beam widths in the
east-west and north-south directions are 32 arc minutes and 50 arc minutes
respectively.
3.7 Millimeter Wave
Telescope:
The 10.4m millimetre wave telescope is operational at the campus of Raman
Research Institute (RRI), Bangalore. The telescope has been successfully tested
for operations at 3.5 mm and 13.5 mm
wavelengths.
3.8 Ooty Radio Telescope
(ORT):
The Ooty Radio
Telescope (ORT) is a cylindrical paraboloid 530m long in N-S direction and 30m
wide in the E-W direction. The effective collecting area is about
800m2. The unique feature of the telescope is that the long axis is
aligned in the north-south direction along a hill with a natural slope of 11º,
which is equal to the latitude of the place. Thus by mechanical rotation of the
telescope in the E-W direction a source in the sky can be tracked continuously
for about 9¹⁄2 hours. The pointing of the telescope in declination is
achieved by electronic phasing of 1056 dipoles along the 500m long focal line of
the parabolic reflector. The ability to track a source with such a large
collecting area makes the ORT one of the most powerful in the world. The
telescope operating at 326.5 MHz and situated in the hills of Nilgiris near Ooty
in South India, started functioning in early 1970. This facility is managed and
run by TIFR.
3.9 Giant
Metre-wave Radio Telescope
(GMRT)
The Giant
Meter –wave Radio Telescope (GMRT), an aperture synthesis array consisting of 30
fully steerable parabolic dishes of 45-m diameter each, is set up about 80km
north of Pune as a national facility for frontline research in radio astronomy
in the frequency range 38 MHz to 1420 MHz. This is a major new instrument
designed to fill the existing worldwide gap in powerful radio telescopes
operating at meter wavelengths. Two of the primary objectives of the telescope
are to detect the highly redshifted 21cm line of neutral hydrogen from
protoclusters or protogalaxies in the early epochs of the universe before galaxy
formation and to detect and study a large number of millisecond pulsars in an
attempt to detect the primordial background of gravitational radiation.
Over the last
year, routine observations of a variety of objects have been carried out using
the GMRT with typically 2-3 days of the week reserved for maintenance and system
tests. The data quality and reliability of the antenna systems and the
30-antenna correlator system has been continuously improved and maps with a rms
noise of a few mJ and dynamic range of 500 and greater are being produced at 325
MHz and higher frequencies. The telescope has been cycled through all its
frequencies, spending typically 4-6 weeks at each frequency. Objects like nearby
galaxies, giant radio galaxies, cluster of galaxies, supernova remnants and the
galactic centre have been mapped at a number of the GMRT frequencies. Extensive
spectral line observations have been made of hydrogen and recombination lines in
galactic and extragalactic radio sources. However at the lower GMRT frequencies,
the data quality has been indifferent, being affected by interference,
ionosphere, instrumental effect and other problems. Single and dual frequency
pulsar observations have also been made using the GMRT Array Combiner and the
DSP based coherent/incoherent dedispersion
machine.
3.10
Udaipur Solar
Observatory (USO):
USO was initiated in 1975 on an island
in the middle of a large lake in Udaipur for solar optical observations. USO
operates its solar telescopes with the primary aim of obtaining high resolution
observations of various phenomena occurring in outer layer of the solar
atmosphere, particularly, in the solar photosphere and chromosphere. The
scientific activity at USO broadly consists of the following components: (i)
Designing, fabrication and modernistion of observational tools, i.e., telescopes
and back-end equipment, digital image acquisition, processing and dissemination,
(ii) coordinated solar observational campaigns, both at national and
international levels, (iii) full disk solar observations for solar flare-patrol,
and solar weather-forecasting programmes, and (iv) high resolution observations,
detailed analysis and modeling of important solar events with the goal of
understanding the basic physics involved in phenomena of flares,
filament/prominence formation and their stability; surges and sprays, filament
eruptions etc.
The optical telescopes and other facilities include the following (i)
12-foot solar spar telescope with 25 cm aperture telescope for observing small
scale high resolution chromospheric structures, and longitudinal component of
the solar magnetic fields, (ii) 6-foot Razdow telescope for full disk H-alpha
synoptic observations of solar activity, and (iii) 15 cm aperture Zeiss Coude
telescope in conjunction with multi-slit Littrow spectrograph for spectral study
of solar prominences, flares and active regions. These facilities have been
augmented with the following new instruments: (i) USO Solar video magnetograph,
(ii) The GONG (Global Oscillation Network Group) full disk dopplergraph and
magnetograph facility.
3.11 IMD
Data Processing System:
The data processing system installed in India Meteorological Department
(IMD) during 1992 for reception and processing of INSAT-2 meteorological data
continued to operate satisfactorily on an operational basis. Meteorological data
received from INSAT-1 and 2 satellites are processed for dissemination of the
data products to the users. The system has improved the quality of the Cloud
Motion Vectors (CMVs) generated from INSAT satellites. The system also derives
Outgoing Longwave Radiation (OLR) and the Quantitative Precipitation Estimates
(QPE) from INSAT data.
3.12 APT Ground
Station:
A network of seven APT
stations of the IMD at Mumbai, Kolkata, Chennai, Poona, Guwahati, Vishakapatnam
and Bhubaneswar has been operating for the reception of low resolution cloud
imagery in the visible and infrared channels from polar orbiting meteorological
satellites of NOAA series of the USA. These cloud pictures are utilised for
weather analysis and forecasting
services.
3.13 HRPT Ground
Stations:
Ground equipment for the reception of Advanced Very High Resolution
(AVHRR) data installed at New Delhi
and Chennai obtains pictures for operational use in the analysis of
different weather systems over India and adjoining areas. These pictures are
extremely useful for analysis of the tropical cyclones, severe local storms etc.
The data provided over 5 different spectral channels has a finer ground
resolution of 1.1km at sub-satellite point both in visible and infra-red
channels. New High Resolution Picture Transmission (HRPT) system for
receiving NOAA-15/16 data from
AMSU-A and AMSU-B along with ITOVS has been installed at IMD,New
Delhi.
3.14 Optical
Telescopes:
Major optical observatories of India are run by the Indian Institute of
Astrophysics (IIA) at Kavalur, by Uttar Pradesh Solar Observatory (UPSO) at
Nainital and by Centre for Advanced Studies in Astronomy (CASA) of Osmania
University at Japal-Rangapur near Hyderabad. Brief description of the telescopes
is given here.
* The Japal-Rangapur Observatory (JRO) of the
Osmania University
This Observatory (695 m above msl) near Hyderabad has a 48-inch telescope
that was commissioned in 1968. It can be used as a Newtonian system, a folded
Cassegranian (Nasmyth) system, a Coude system or as a Baker system. A Meinel
Spectrograph is available for use at the Nasmyth focus in addition to a number
of standard items of equipment.
* The Uttar Pradesh State Observatory
(UPSO)/Uttaranchal State
Observatory
The principal
equipments at the Observatory are its telescopes. The State Observatory, which
was started with a 25-cm f/15 (Cooke, UK) refractor, today has four telescopes
of 104-cm, 56-cm, and 38-cm apertures, for cometary, planetary, galactic and
extra -galactic research and a few telescopes for solar research. The 25-cm
telescope was very useful in the initial photographic and photoelectric
programmes. Presently, the 15-cm, f/15 reflector (Ziess, Jena), acquired in
1960 and the 25-cm telescope is
being used for acquainting the visitors to the Observatory. The Observatory was
only centre in India for about two decades using 79/51-cm Baker-Nunn Satellite
Camera along with precision timing. The Observatory has an electronic workshop,
a machine workshop, a fine technics laboratory which includes aluminizing unit
and optics workshop, well equipped library, a computer section and a small
photographic section
* Observatories of the Indian Institute of
Astrophysics
Kavalur observatory houses the 2.34 m Vainu Bappu Telescope,
operational since 1985. This Cassegrainian telescope has an equatorial
horse-shoe yoke mounting with hydrostatic bearings. Apart from photography,
Coude focus has also been made available. Some back-end instruments are being.
Significant gain was achieved in the tracking accuracy of the telescope. The CCD
camera used earlier was replaced by a more efficient, large-format (1024 x 1024
pixels) CCD. A new efficient, computer-controlled spectrograph has been acquired
for spectroscopy and spectrophotometry and put in operation durign 1996-97.
A polarimetry
option is now available with the spectrograph, which was put to use for
spectropolarimetry of comets. The 234 cm diameter primary mirror of the
telescope was re-aluminised during the period. The misalignment detected in the
long focus camera of the new spectrograph was corrected in IIA’s Photonics Lab.
Additionally available national facilities include a Perkin Elmer data
digitising system and an instrumentation cell at Bangalore. The second large
telescope at Kavalur is a 102 cm telescope operational with Coude and Cassegrain
systems backed up by spectrograph, photometers and spectrum scanners with
on-line computing facilities. The Institute also has a specialised optical
laboratory and optical workshop in Bangalore for grinding and figuring optical
mirrors upto 2.5m diameter.
3.15
Infrared Telescope Facility at
Gurushikhar:
The 1.2 m telescope at
Mt. Abu has been fully operational since 1996. This is an f/13 Cassegrain system
and the telescope is equipped with a range of backend instruments : IR camera
with 256 x 256 pixel; a large format thinned back illuminated CCD camera (1024 X
1024 pixel); Imaging Fabry-Perot Spectrometer; optical and infrared polarimeter,
IR fast photometer for lunar occultation and a grating spectrograph. The two
channel fast Infrared photometer for obtaining simultaneously lunar occultation
light curves at two IR wavelengths has been undergoing tests at the Gurushikhar
telescope. The telescope has been successfully exploited for a number of
observational programmes.
3.16 Medium Scale Facilities
for Study in Aeronomy
Over the past several years a large number of medium scale scientific
facilities have been developed and are currently in operation to conduct
different experiments and data collection for studying various atmospheric and
ionospheric phenomena. A few important facilities are the following: (a) VHF
coherent radar to study the electrojet phenomenon and ionospheric irregularities
at Thumba, (b) HF-Doppler radars at Kodaikanal and Waltair to study F-region
dynamics, (c) Chain of ionosondes at Ahmedabad, Delhi, Kodaikanal, Kolhapur,
Thiruvananthapuram, Sriharikota and Waltair for regular monitoring of
ionosphere, (d) high power pulsed ruby lidar , CW (Ar+) and Nd-YAG lidar systems at
Thiruvananthapuram giving information on atmospheric aerosol density
distribution upto 30km, (e) a six-station chain of Dobson's spectrophotometers
to compute total ozone content and vertical ozone distribution, (f) a chain of
meteorological balloon launching stations for measuring temperature, winds,
humidity and ozone profiles up to lower stratospheric heights; (g) balloon,
rocket and satellite payload development facilities at Ahmedabad, Bangalore,
Thumba, New Delhi, Mumbai and Pune, (h) a number of airglow emission photometers
in visible and infrared wavelengths at Ahmedabad and Pune, (i) a chain of stations for receiving
satellite radio beacon transmission in VHF and UHF bands for deriving total
electron content and ionospheric scintillations, (j) a chain of
multi-wavelength radiometers and B-UV photometers for measuring geographical
distribution of atmospheric aerosol loading and ultraviolet flux received
on the earth's surface, (k) a chain of Fabry-Perot Spectrometers for
co-ordinated airglow measurements at Ahmedabad, Pune and Kodaikanal, (l)
laboratory set-up for measurement of photo absorption cross-sections,
fluorescence spectra, radiative life times of molecules, (m) Nd-Yag laser system
at PRL, Ahmedabad for studying atmospheric aerosols and temperatures, (n)
partial reflection radar at Tirunelveli for measurement of mesospheric winds and
waves.
3.17 Cyclone Warning Dissemination
System (CWDS):
There are 250 CWDS stations (set up by IMD) along the coastal districts of India, covering maritime states like West Bengal, Orissa, Andhra Pradesh, Tamilnadu, Kerala, Karnataka, Maharashtra, Goa and Gujarat. The service is used for transmitting cyclone warnings via INSAT satellites to the local people in areas likely to be affected by the cyclone. This is the most effective medium of transmission because, it is least affected by adverse weather conditions in comparison to landline media (T/P, Telex, W/T etc.). This has been in operation since 1986. The service has been very useful in saving human lives and property during cyclones, a