Published on: November 30, 2022



Why in news?

 SARAS 3, a radio telescope designed and built at the Raman Research Institute (RRI) floating in Karnataka waters throws light on nature of early stars and galaxies


  • Scientists have determined properties of radio luminous galaxies formed just 200 million years post the Big Bang, a period known as the Cosmic Dawn
  • This telescope provides an insight to the properties of the earliest radio loud galaxies that are usually powered by supermassive black holes.

About SARAS 3(Shaped Antenna measurement of the background Radio Spectrum 3)

  • Indigenously designed and built at Raman Research Institute was deployed over Dandiganahalli Lake and Sharavati backwaters, located in Northern Karnataka, in early 2020.
  • The Commonwealth Scientific and Industrial Research Organisation (CSIRO) in Australia, along with collaborators at the University of Cambridge and the University of Tel-Aviv, estimated the energy output, luminosity, and masses of the first generation of galaxies that are bright in radio wavelengths.

What are the Deeper insight of the project?

  • It had improved the understanding of astrophysics of Cosmic Dawn by telling astronomers that less than 3% of the gaseous matter within early galaxies was converted into stars, and that the earliest galaxies that were bright in radio emission were also strong in X­rays, which heated the cosmic gas in and around the galaxies
  • Insight on understanding the  constraints on the masses of the early galaxies, along with limits on their energy outputs across radio, X-ray, and ultraviolet wavelengths,
  • SARAS 3 has been able to put an upper limit to excess radiation at radio wavelengths, lowering existing limits set by the ARCADE and Long Wavelength Array (LWA) experiments in the US.