FAST RADIO BURSTS (FRBs)

FAST RADIO BURSTS (FRBs)

TOPIC: Science & Tech

Context- Astronomers of National Centre of Radio Astrophysics (NCRA-TIFR) in Pune and the University of California in the U.S. have used the Giant Metrewave Radio Telescope (GMRT) to map the distribution of atomic hydrogen gas from the host galaxy of a fast radio burst (FRB) for the first time.

Concept-

Fast radio bursts:

• Fast radio bursts are extremely bright radio waves from distant galaxies that last for only a few milliseconds because of which it is difficult to detect them and determine their position in the sky.
• FRB produces repeated, very short bursts, and these have been found to arise in the outskirts of a spiral galaxy half a billion light-years away.
• It was first discovered in 2007.
• In 2020, the National Aeronautics and Space Administration (NASA) spotted FRB for the first time in the Milky Way.
• A defining property of these bursts is their dispersion (scattering or separation), the bursts produce a spectrum of radio waves, and as the waves travel through matter, they spread out or disperse with bursts at higher radio frequencies arriving at telescopes earlier than those at lower frequencies. This dispersion allows researchers to learn about two important things:
  1. They can measure this dispersion to learn about the stuff that radio bursts pass through as they travel toward Earth.
  2. They can indirectly determine how far apart things are.
• It can be used to understand the three–dimensional structure of matter in the universe and to learn about poorly understood early moments in the evolution of the universe.

About GMRT:

• The GMRT located near Pune is an array of thirty fully steerable parabolic radio telescopes of 45-metre diameter, observing at metre wavelengths.
• It is operated by the National Centre for Radio Astrophysics (NCRA), a part of the Tata Institute of Fundamental Research, Mumbai.
• Astronomers from all over the world regularly use this telescope to observe many different astronomical objects such as Ionized Interstellar atomic Hydrogen Regions, galaxies, pulsars, supernovae, and Sun and solar winds.