Ooty Radio Telescope, Nilgiris
Ooty Radio Telescope is located in Muthorai in picturesque Nilgiris Hills
near Ooty Hill Station in Ooty Taluk of Nilgiris District of Tamilnadu. It is part of the National Centre for Radio
Astrophysics (NCRA) of the well-known Tata Institute of Fundamental
Research (TIFR) which is funded by the Government of India through the Department of atomic energy.
History
The structure of the radio
telescope was designed in July 1963. Muthorai village near Ooty was
selected as the suitable location and the construction work began in 1965. The
telescope was completed in 1970. Normal post commissioning and calibration
use began in 1971.
Ooty Radio Telescope
The Ooty Radio
telescope has been designed and fabricated with domestic Indian
technological resources. It continues to be one of the most sensitive radio
telescopes in the world. Observations made using this telescope have led to
important discoveries and to explain various phenomena occurring in our solar
system and in other celestial bodies. The Ooty Radio Telescope
(ORT) is a 530-metre (1,740 ft) long and 30-metre (98 ft)
cylindrical parabolic antenna. It operates at a
frequency of 326.5 MHz with a maximum bandwidth of 15 MHz at the
front-end. The reflecting surface of the telescope is made of 1100 thin
stainless-steel wires running parallel to each other for the entire length of
the cylinder and supported on 24 steerable parabolic frames.
An array of 1056 half-wave
dipoles in front of a 90 degrees corner reflector forms the primary feed of the
telescope. It has an angular resolution of 2.3 deg x 5.5 sec(dec). The
large size of the telescope makes it highly sensitive. As an example, it is in
principle capable of detecting signals from a mere 1-watt radio station located
10 million km away in space. The telescope sits on a natural slope of 11°,
which matches the latitude of the location. This gives the telescope an equatorial
mount which allows tracking of celestial sources for up to ten
hours in the east-west direction. In the north-south direction, the
telescope operates as a phased-array and is steerable by varying the phase
gradients.
The telescope can be operated in
either total power or correlation mode. In each mode, 12 beams are formed, and
Beam 1 is the southernmost beam and Beam 12 is the northern most. These 12-beam
systems are useful in sky-survey type of observations. Recently, the reflecting
surface of the ORT has been refurbished. A new digital back-end has been built
for the ORT by the colleagues at Raman Research Institute (RRI), Bangalore. The
ORT has produced results on radio
galaxies, quasars, supernovae
and pulsars, One
long-term program determined the angular structure of several hundred distant
radio galaxies and quasars using the lunar
occultation method. The application of this database to
observational cosmology provided independent evidence
against the Steady State theory and supported
the Big Bang model of the universe.
The telescope is currently being
used mainly to observe interplanetary scintillation,
which may provide valuable information about the solar
wind and magnetic
storms that affect the near - earth environment. Interplanetary
scintillation observations provide a database to understand space weather
changes and their predictability. The telescope has been used for observing
pulse nulling. The interferometer can be used at Channel
37 (608 MHz to 614 MHz, important radio astronomy
frequencies) with lesser performance.
Contact
Radio Astronomy Centre,
National Centre for Radio Astro
Physics,
Tata Institute of Fundamental
Research,
Ooty – 643 001
Phone: +91 423 255 0334 / 255 0335
Fax: +91 423 255 0135
Connectivity
Ooty Radio Telescope is
located at about 6 Kms from Ooty, 7 Kms from Ooty Bus Stand, 7 Kms from Ooty
Railway Station, 24 Kms from Coonoor, 37 Kms from Kotagiri, 55 Kms from Mettupalayam
Railway Station, 89 Kms from Coimbatore and 92 Kms from Coimbatore Airport.
Ooty is well connected to Coimbatore, Kerala and Karnataka.
