FAST RADIO BURST

Subject : Science & tech

Context : NASA has reported that on April 28, it observed a mix of X-ray and radio signals never observed before in the Milky Way. Significantly, the flare-up it observed included the first fast radio burst (FRB) seen within the galaxy.

Concept :

• The X-ray portion of the simultaneous bursts was detected by several satellites, including NASA’s Wind mission, and the radio component was discovered by the Canadian Hydrogen Intensity Mapping Experiment (CHIME).
• Further, a NASA-funded project called Survey for Transient Astronomical Radio Emission 2 (STARE2) also detected the radio burst seen by CHIME.

Fast Radio Burst :

• FRBs are super intense, millisecond-long bursts of radio waves produced by unidentified sources in the space.
• Their discovery in 2007 by American astronomer Duncan Lorimer led to the term ‘Lorimer Bursts’.
• Since then, just a few dozen similar events have been observed in data collected by radio telescopes around the world, building evidence that points to a variety of potential causes.
• Only a handful of emissions have been traced to specific areas of the sky, indicating sources in other galaxies.
• The flash of radio waves is incredibly bright if distant, comparable to the power released by hundreds of millions of suns in just a few milliseconds.
• This intensity suggests powerful objects like black holes and neutron stars could be involved.
• The events were once considered to be largely transient – they seemed to happen once, without obvious signs of a repeat emission. However, a number of such bursts have been identified since then.

Why are they significant?

• First noticed in 2018 by the Canadian observatory the waves have created ripples across the globe for one reason — they arrive in a pattern.
• This gave birth to theories that they could be from an alien civilization.
• Initially, it was believed that the collision of black holes or neutron stars triggers them.
• But the discovery of repeating FRBs debunked the theory of colliding objects.