Canadian and iisc astronomers detect radio signal in distant galaxy using Giant Metrewave Radio Telescope (GMRT).

• Astronomers from McGill University (Canada) and Indian Institute of Science (MSc), Bengaluru used data from GMRT to detect a radio signal originating from atomic hydrogen in an extremely distant galaxy at redshift z=1.29.
  • Redshift represents signal’s wavelength change depending on the object’s location and movement.
  • A greater value of z indicates a farther object.
• Atomic hydrogen is the basic fuel required for star formation in a galaxy.
  • When hot ionised gas from surrounding medium of a galaxy falls onto universe, gas cools and forms atomic hydrogen.
  • This then becomes molecular hydrogen and eventually leads to formation of stars.
• Detection was made possible by gravitational lensing phenomenon.
  • In gravitational lensing, light emitted by source is bent due to presence of another massive body between target galaxy and observer, effectively resulting in magnification of signal.

About GMRT

• It is an instrument for studying astrophysical phenomena, ranging from nearby Solar system to edge of observable Universe, at low radio frequencies.
• It is operated by National Centre of Radio Astrophysics (NCRA), which is part of Tata Institute of Fundamental Research.
• GMRT is located in Junnar near Pune.