Home » Blog » XPoSat: X-Ray Polarimeter Satellite

XPoSat: X-Ray Polarimeter Satellite

By Amigos IAS

Why is it in the news?

  • Indian Space Research Organisation (ISRO) announces the launch of India’s first X-Ray Polarimeter Satellite (XPoSat).
  • The other such major mission is NASA’s Imaging X-ray Polarimetry Explorer (IXPE) that was launched in 2021.


About XPoSat

  • Launched by the Polar Satellite Launch Vehicle (PSLV) from Satish Dhawan Space Centre in Sriharikota.
  • Aims to investigate the polarization of intense X-Ray sources.


Polarisation of X-Ray Sources

·       Intrinsic property of light.

·       Provides deeper insight into processes and local anisotropies of fields (electric/magnetic/gravitational).

·       X-Ray polarization serves as a crucial diagnostic tool for examining the radiation mechanism and geometry of celestial sources.



XPoSat Mission

  • It is India’s first dedicated polarimetry mission.
  • Observation from Low Earth Orbit (~650 km altitude, low inclination of approximately six degrees).
  • Carries two scientific payloads:
  • POLIX (Polarimeter Instrument in X-rays): Measures degree and angle of polarization in the medium X-ray energy range (8-30 keV photons). It is being developed by Raman Research Institute (RRI), Bangalore in collaboration with U R Rao Satellite Centre(URSC).
  • XSPECT (X-ray Spectroscopy and Timing): Provides spectroscopic information within the energy range of 0.8-15 keV. It was developed by the U.R.Rao Satellite Centre,ISRO.
  • Payloads observe X-Ray sources during the spacecraft’s transit through Earth’s shadow (eclipse period).
  • Mission life expected to be approximately five years.



  • Enables measurements of mass and spin of accreting black holes.
  • Enhances comprehension of the source’s geometric arrangement and local properties.
  • Polarimetry measurements add dimensions to understanding emission processes from astronomical sources.


Launch Vehicles


India has three active operational launch vehicles:

·       PSLV (Polar Satellite Launch Vehicle): Versatile, highest success rate, used for various payloads.

·       GSLV (Geosynchronous Satellite Launch Vehicle): Capable of launching up to 2-tonne class communication satellites with indigenous Cryogenic Upper Stage.

·       LVM3 (Geosynchronous Satellite Launch Vehicle Mk-III): Next-gen launch vehicle, capable of launching 4-tonne class communication satellites and 10-tonne class payloads to Low Earth Orbit (LEO).


Upcoming Missions of ISRO

·       Gaganyaan: Human spaceflight project to demonstrate capability by launching a crew of 3 members for a 3-day mission.

·       NASA-ISRO SAR (NISAR): Jointly developed Low Earth Orbit observatory to map the entire globe in 12 days, providing consistent data for understanding Earth’s ecosystems.

·       SPADEX: Twin spacecraft mission to mature technologies related to orbital rendezvous, docking, formation flying, with applications in human spaceflight, in-space satellite servicing, and other proximity operations.

Signup for newsletter

Receive notifications straight into your inbox

Leave a comment

Item added to cart.
0 items - 0.00

Discover more from AMIGOS IAS

Subscribe now to keep reading and get access to the full archive.

Continue reading