AstroSat, India’s premier multi-wavelength space-based observatory, has recently identified a millisecond burst emanating from a novel neutron star with an exceptionally high magnetic field, known as a magnetar. This discovery holds the potential to deepen our comprehension of these celestial bodies and the extreme astrophysical conditions they embody.


GS-03 (Science and Technology)


  • AstroSat, designed for multi-wavelength astronomical observations, captured intense sub-second X-ray bursts originating from a distinctive neutron star with an ultra-high magnetic field, identified as a magnetar.
  • This finding promises valuable insights into the intricate astrophysical environments characterizing magnetars.


  • Magnetars are young and highly magnetized neutron stars that display a wide array of X-ray activity including short bursts, large outbursts, giant flares, and quasi-periodic oscillations, often coupled with interesting timing behavior including enhanced spin-down, glitches, and antiglitches.
  • Magnetars, a subclass of neutron stars, exhibit magnetic fields significantly surpassing those found on Earth.
  • To illustrate, the magnetic field of a magnetar exceeds one quadrillion times the strength of Earth’s magnetic field.
  • The emission of high-energy electromagnetic radiation from magnetars is attributed to the decay of their magnetic fields.
  • These celestial objects showcase notable temporal variations, including slow rotation, rapid spin-down, and brief yet luminous bursts lasting from milliseconds to months.
  • An illustrative example is SGR J1830-0645, pinpointed by NASA’s Swift spacecraft in October 2020.

Research Details:

  • A collaborative effort between researchers from the Raman Research Institute and Delhi University delved into the characteristics of the magnetar SGR J1830-0645 using AstroSat’s instruments—the Large Area X-Ray Proportional Counter (LAXPC) and Soft X-Ray telescope (SXT).
  • The study uncovered 67 concise sub-second X-ray bursts, averaging a duration of 33 milliseconds. The most luminous burst observed endured for approximately 90 milliseconds.
  • The study concluded that SGR J1830–0645 represents a distinctive magnetar, featuring an emission line in its spectra.
  • The pulsed component of the overall X-ray emission exhibited notable fluctuations across different energy levels. This research contributes valuable data to our evolving understanding of magnetars and their dynamic behavior.