QUE : India’s mission X-ray Polarimeter Satellite (XPosat) has created history with its successful launch. Explain the significance of XPosat and its various payloads by giving information about it.

 Recently, the Indian Space Research Organisation (ISRO) launched the first satellite XPoSat (XPoSat) to study cosmic sources and X-ray polarization like black holes, neutron stars, magnetars etc.

•  XPoSat is India’s first polarimetry mission to study various aspects of cosmic X-ray sources emitted under adverse conditions. Its spacecraft will carry two scientific payloads to low Earth orbit.
  
•  Exposat Orbit: 7028. 317 km, PSLV C58 used for launch, The primary payload POLEX (Polarimeter Instrument in X rays) will measure the polarimetry parameters of medium X-rays of 8-30 keV photon energy range having space origin. The other payload XSPECT (X ray Spectroscopy and Timing) payload will provide spectroscopic information in the energy range of 0.8-15 keV.
  
•  The system of radiation emitted from space sources like black holes, neutron stars, active galactic nuclei, pulsars with nebulae etc. arises through complex physical processes and is a difficult challenge to understand. Despite the information about such radiations from various sources, it was a very difficult task for astronomers to know the exact nature. This payload provides important information about the degree and angle of polarization and thus becomes a suitable tool for understanding the emission process required from this source.
  
•  This satellite is likely to change many theories related to radiation in astronomy. In which Indian science will make an important contribution to global astronomy through Exposat.

•  Payload:

•  POLIX: POLIX is an X-ray polarimeter for space observation in the 8-30 keV energy band. This payload has been developed by Ramm Research Institute, Bangalore in collaboration with U. R. Rao Satellite Centre. Its instrument consists of a collimator, scatterer and four X-ray proportional detectors. POLIX will be able to observe about 40 illuminated space sources of various categories which will operate during the five-year timeline of the Exposat mission. This is the first payload to carry dedicated instruments for polarimetry measurements in the medium X-ray energy band.

•  XSPECT: XSPECT is the X-ray spectroscopy and timing payload on Exposat, which can provide fast timing and spectroscopic resolution in soft X-rays. XSPECT will study several sources such as X-ray pulsars, black hole binaries, low magnetic field neutron stars, etc.