ASTROSAT (Syllabus: GS Paper 3 – Sci and Tech)

Context: India's first multi-wavelength space telescope, AstroSat, has successfully detected its 600th Gamma-ray Burst (GRB), an event named GRB 231122B.

Astrosat

• About: India's premier multi-wavelength space observatory, AstroSat, focuses on studying celestial sources in X-ray, optical, and UV spectral bands simultaneously.
• Launched by: The Indian PSLV from Sriharikota on September 28, 2015
• Orbit: 650 km orbit inclined at an angle of 6 degrees to the equator.
• Mission Operations: The spacecraft is managed by the Mission Operations Complex (MOX) at ISRO's Telemetry, Tracking, and Command Network (ISTRAC) in Bengaluru throughout its mission life.
• Duration: Around 5 years, ensuring sustained scientific observations.
• Scientific Payloads: Equipped with five scientific payloads, AstroSat enables imaging and studying the temporal and spectral properties of cosmic sources in various wavelengths on a unified platform.
• Objectives:

oInvestigate high-energy processes in binary star systems containing neutron stars and black holes.

oEstimate magnetic fields of neutron stars.

oExplore star birth regions and high-energy processes in star systems beyond our galaxy.

oDetect new, briefly bright X-ray sources in the sky.

Gamma-ray bursts (GRBs):

• About: They are the most powerful and violent explosions in the known universe. These brief flashes of high-energy light result from some of the universe's most explosive events, including the birth of black holes and collisions between neutron stars. 
• Lasting a few milliseconds to several minutes, according to NASA, GRBs can be hundreds of times brighter than an average supernova, making them as luminous as a million trillion suns.
• Thus, when a GRB erupts, it briefly becomes the brightest source of electromagnetic radiation in the observable universe.