The Giant Metrewave Radio Telescope (GMRT), located near Pune, Junnar, near Narayangaon at khodad in India, is an array of thirty fully steerable parabolic
radio telescope
A radio telescope is a specialized antenna and radio receiver used to detect radio waves from astronomical radio sources in the sky. Radio telescopes are the main observing instrument used in radio astronomy, which studies the radio frequency ...
s of 45 metre diameter, observing at metre
wavelength
In physics, the wavelength is the spatial period of a periodic wave—the distance over which the wave's shape repeats.
It is the distance between consecutive corresponding points of the same phase on the wave, such as two adjacent crests, tro ...
s. It is operated by the
National Centre for Radio Astrophysics
The National Centre for Radio Astrophysics (NCRA) (Hindi:राष्ट्रीय रेडियो खगोल भौतिकी केन्द्र) of India is a research institution in India in the field of radio astronomy is located ...
(NCRA), a part of the
Tata Institute of Fundamental Research
Tata Institute of Fundamental Research (TIFR) is a public deemed research university located in Mumbai, India that is dedicated to basic research in mathematics and the sciences. It is a Deemed University and works under the umbrella of the ...
,
Mumbai
Mumbai (, ; also known as Bombay — the official name until 1995) is the capital city of the Indian state of Maharashtra and the ''de facto'' financial centre of India. According to the United Nations, as of 2018, Mumbai is the second- ...
. It was conceived and built under the direction of Late Prof.
Govind Swarup
Govind Swarup (March 23, 1929 – September 7, 2020) was a pioneer in radio astronomy. In addition to research contributions in multiple areas of astronomy and astrophysics, he was a driving force behind the building of "ingenious, innovative ...
during 1984 to 1996. It is an
interferometric
Interferometry is a technique which uses the ''interference'' of superimposed waves to extract information. Interferometry typically uses electromagnetic waves and is an important investigative technique in the fields of astronomy, fiber op ...
array with baselines of up to .
It was recently upgraded with new receivers, after which it is also known as the Upgraded Giant Metrewave Radio Telescope (uGMRT).
Location
The GMRT Observatory is located about 80 km north of
Pune
Pune (; ; also known as Poona, (List of renamed Indian cities and states#Maharashtra, the official name from 1818 until 1978) is one of the most important industrial and educational hubs of India, with an estimated population of 7.4 million ...
at
Khodad. A nearby town is
Narayangaon
Narayangaon is a town in the Junnar taluka of the Pune district of Maharashtra state, India. Water is abundant because of its proximity to the major dams, the western ghats, and the Sahyadri mountain range.
Geography
Narayangaon is located 656 ...
which is around 9 km from the telescope site. The office of NCRA is located in the
Savitribai Phule Pune University campus.
Science and observations
One of the aims for the telescope during its development was to search for the highly
redshifted 21-cm line radiation from primordial neutral hydrogen clouds in order to determine the epoch of galaxy formation in the
universe
The universe is all of space and time and their contents, including planets, stars, galaxies, and all other forms of matter and energy. The Big Bang theory is the prevailing cosmological description of the development of the universe. ...
.
Astronomers from all over the world regularly use this telescope to observe many different astronomical objects such as
HII regions
An H II region or HII region is a region of interstellar atomic hydrogen that is ionized. It is typically in a molecular cloud of partially ionized gas in which star formation has recently taken place, with a size ranging from one to hundred ...
,
galaxies,
pulsars
A pulsar (from ''pulsating radio source'') is a highly magnetized rotating neutron star that emits beams of electromagnetic radiation out of its magnetic poles. This radiation can be observed only when a beam of emission is pointing toward E ...
,
supernovae, and Sun and
solar wind
The solar wind is a stream of charged particles released from the upper atmosphere of the Sun, called the corona. This plasma mostly consists of electrons, protons and alpha particles with kinetic energy between . The composition of the sol ...
s.
In August 2018, the most distant galaxy ever known, located at a distance of 12 billion light years, was discovered by GMRT.
In February 2020, it helped in the observation of the biggest explosion in the history of the universe, the
Ophiuchus Supercluster explosion
NeVe 1 is a supergiant elliptical galaxy and the central, dominant member of the Ophiuchus Cluster, about 411 million light-years away from Earth behind the Zone of Avoidance region of the sky. It is notable for being the host galaxy of the O ...
.
Activities
Each year on
National Science Day
National Science Day is celebrated in India on February 28 each year to mark the discovery of the Raman effect by Indian physicist Sir C. V. Raman on 28 February 1928.
For his discovery, Sir C.V. Raman was awarded the Nobel Prize in Physics i ...
the observatory invites the public and pupils from schools and colleges in the surrounding area to visit the site where they can listen to explanations of radio astronomy, receiver technology and astronomy from the engineers and astronomers who work there. Nearby schools/colleges are also invited to put their individual science experiments in exhibition and the best one in each level (primary, secondary school and Jr. college) are awarded.
Visitors are allowed into GMRT only on Fridays in two sessions - Morning (1100 hrs - 1300 hrs) and Evening (1500 hrs to 1700 hrs).
See also
*
List of radio telescopes
This is a list of radio telescopes – over one hundred – that are or have been used for radio astronomy. The list includes both single dishes and interferometric arrays. The list is sorted by region, then by name; unnamed telescopes are in r ...
References
External links
GMRT HomepageY-shaped arrayGMRT Visit
{{Portal bar, India, Astronomy, Stars, Spaceflight, Outer space, Solar System, Education, Science
Radio telescopes
Interferometric telescopes
Astronomical observatories in India
Tata Institute of Fundamental Research
1995 establishments in Maharashtra
Pune district
Research institutes in Maharashtra