Astrosat Detects Millisecond X-Ray Burst From New Magnetar

Astrosat, India's first multi-wavelength space-based observatory, has detected a bright sub-second X-ray burst from a new and distinctive neutron star with an ultrahigh magnetic field (magnetar).

• This discovery may help understand the interesting extreme astrophysical conditions of magnetars.
• Scientists performed timing and spectral analysis of this magnetar using two instruments aboard Astrosat:
  • Large Area X-ray Proportion Counter (LAXPC) 
  • Soft X-ray Telescope (SXT)

What are Magnetars?

• Magnetars are neutron stars that have ultrahigh magnetic fields that are much stronger than the terrestrial magnetic field.
• In general, the magnetic field of the magnetar is one quadrillion times stronger than the Earth's magnetic field.
• The high-energy electromagnetic radiation emitted by magnetars results from the decay of their powerful magnetic fields.
• Magnetars exhibit strong temporal variability, typically including slow spins, fast spins and bright but short bursts that last for months.
• One such magnetar, called SGR J1830-0645, was discovered by NASA's Swift spacecraft in October 2020.

About AstroSat:

• Astrosat is the first dedicated Indian Astronomy Mission.
• Its objective is to study celestial sources in the X-ray, optical and UV spectral bands simultaneously.
• It was launched by PSLV-C30 from the Satish Dhawan Space Centre, Sriharikota, in September 2015.
• ISRO Telemetry Tracking and Command Network (ISTRAC) manages the operations of Astrosat.

What is a neutron star?

• A neutron star is a dense and compact stellar body that is formed from the remains of the core of a massive star after a supernova explosion.
• These stars are among the densest objects known in the universe, compressing an enormous mass into a relatively small size.
• The discovery of pulsars in 1967 provided the first evidence of the existence of neutron stars. Pulsars are neutron stars that emit pulses of radiation once every rotation.