Fast Radio Bursts (FRB)

17.10.2023

Fast Radio Bursts (FRB) , Daily Current Affairs , RACE IAS : Best IAS Coaching in Lucknow 

Why in the news?

According to a recent study by astronomers at the University of Tokyo, fast radio bursts in space are caused by 'starquakes'.

      About Fast Radio Bursts:

• Fast radio bursts were first discovered in 2007.
• Fast radio bursts are invisible to the human eye but can be seen by radio telescopes. They come to Earth from extragalactic sources.
• FRBs are divided into two broad categories.
  • Repetitive ones.
  • Without repetition.

• Fast radio bursts are a bright and brief burst of electromagnetic radiation (light) seen at radio-wave frequencies. Which usually last for a very short time.
• Some fast radio bursts are repeated, but the vast majority occur once and then disappear forever.
• They reach Earth from distant galaxies, they last only milliseconds (thousandths of a second) but within such a short time, they can release energy equivalent to 500 million suns.
• Scientists don't know for sure what causes the intense radio bursts.
• However, the current prevailing theory is that at least some FRBs are emitted by neutron stars.
• These stars form when a supergiant star collapses, leaving a superdense core just 20–40 kilometers across that is (on average) eight times the mass of our Sun.
• Magnetars are neutron stars with extremely strong magnetic fields, and have been observed to emit FRBs.

Recent studies from astronomers at the University of Tokyo:

• New research from the University of Tokyo has looked at the timing and energy of FRBs and found clear differences between FRBs and solar flares.
• A study analyzing thousands of FRBs showed that FRBs have more in common with earthquakes than solar flares
• The study found that 'starquakes' are responsible for the formation of FRBs.
• It was found that FRBs are emitted from a magnetar.
• The magnetar is the remnant of a star after a supernova. It is a type of neutron star whose core has collapsed.
• The interior of a neutron star is the densest place in the universe, comparable to the interior of an atomic nucleus.

Major similarities between FRBs and earthquakes:

The study team found that there were four key similarities between FRBs and earthquakes.

• First, the probability of a single FRB and earthquake causing aftershocks appears to be between 10% and 50%.
• Second, the rate at which shocks occur decreases with time as a power of magnitude.
• After this, the rate always remains constant after an earthquake.
• Even though the average rate of FRB-earthquake activity varies considerably.

  How FRBs are generated:

• Magnetars are one of the most powerful magnetic objects in the universe.
• The extremely powerful magnetic field distorts the star's shape and pulls it outward. While the collapsed core creates an inward pull.
• Due to the interaction between these two opposite forces, the surface of the star breaks and an earthquake (starquake) occurs. This results in FRBs.

Importance of studying FRB:

• The unique properties of fast radio bursts and their host galaxies, combined with recent technological advances, have given researchers hope that these events can be used to answer some long-standing questions about the universe.
• It can be used to understand the three-dimensional structure of matter in the universe.