What is it?
- SARAS is a niche high-risk high-gain experimental effort of Raman Research Institute to detect extremely faint radio wave signals from the depths of time, from our “Cosmic Dawn” when the first stars and galaxies formed in the early Universe.
- Reverberations of the Big Bang that birthed our universe 13.8 billion years continue to linger in a swathe of radiation called the cosmic microwave background (CMB).
- The cosmic microwave background (CMB) is leftover radiation from the Big Bang or the time when the universe began.
- Detecting a faint signal from such an early period of the Universe is extremely difficult. The celestial signal is exceptionally faint – buried in sky radio waves that come to us from the gas in our own Galaxy, the Milky Way, which are a million times brighter.
- The SARAS 3 radio telescope invented and built by the astronomers at Raman Research Institute(RRI) is the first telescope worldwide to reach the required sensitivity.
- The Raman Research Institute was founded in 1948 by the Indian physicist and Nobel Laureate, Sir C V Raman. RRI is an autonomous research institute engaged in research in basic sciences receiving funds from the Department of Science and Technology of the Government of India.
What are Radio waves
- In the electromagnetic spectrum, radio waves have the longest wavelengths.
- They range in size from a football to the size of our whole planet.
- In the late 1880s, Heinrich Hertz demonstrated the existence of radio waves.
- We may listen to music by tuning a radio to a certain wavelength (or frequency). The radio “receives” these electromagnetic radio waves and transforms them to mechanical vibrations in the speaker, resulting in the sound waves you hear.
What are Radio Telescopes
- Radio telescopes are used to examine radio radiation from stars, galaxies, black holes, and other celestial phenomena that occur naturally.
- They can also be used to broadcast and reflect radio light from our solar system’s planetary bodies.
- The longest wavelengths of light, spanning from 1 millimetre to over 10 metres, are seen by these specially built telescopes.
Why in News
- Using data from the EDGES radio telescope, a team of researchers from Arizona State University (ASU) and MIT in the United States discovered a signal from stars forming in the early cosmos in 2018.
- But SARAS 3(updated version of SARAS) found no evidence of it.