According to ISRO, XPoSat Mission is scheduled for observation from Low Earth Orbit (LEO) at an altitude of approximately 650 km and a low inclination of about 6 degrees. XPoSat carries two scientific payloads designed for simultaneous studies of temporal, spectral, and polarization features of bright X-ray sources, ISRO says

India is gearing up to make a significant stride in space-based X-ray astronomy with the launch of its first X-ray polarimeter Satellite (XPoSat). This mission led by ISRO, aims to investigate the polarization of intense X-ray sources. With this mission, ISRO is set to establish a new benchmark in the field of astronomy. Check here to know all about ISRO's XPoSat mission.

X-ray Polarimeter Satellite (XPoSat) Mission

The X-ray Polarimeter Satellite (XPoSat) is scheduled for observation from Low Earth Orbit (LEO) at an altitude of approximately 650 km and a low inclination of about 6 degrees. As mentioned on the official website of ISRO, XPoSat carries two scientific payloads designed for simultaneous studies of temporal, spectral, and polarization features of bright X-ray sources. The mission's primary payload, POLIX (Polarimeter Instrument in X-rays) has been developed by the Raman Research Institute in Bengaluru with support from ISRO centres. It focuses on measuring polarimetry parameters in the medium X-ray energy range of 8-30 keV. Along with this, the XSPECT (X-ray Spectroscopy and Timing) payload provides spectroscopic information within the energy range of 0.8-15 keV. It is developed by the U R Rao Satellite Centre (URSC).

Main Objectives

The objectives of the XPoSat mission are multifaceted. It aims to measure X-ray polarization in the 8-30 keV energy band emitted from X-ray sources, while also conducting long-term spectral and temporal studies of cosmic X-ray sources in the 0.8-15 keV energy band. The mission's anticipated lifespan is around five years, during which the payloads will observe X-ray sources during the spacecraft's transit through Earth's shadow, specifically during the eclipse period.

One of the key aspects highlighting the significance of XPoSat is its role as a diagnostic instrument for exploring the radiation mechanism and geometry of astronomical sources. ISRO emphasizes that scientists can leverage XPoSat to calculate the mass and spin of accreting black holes, explore accretion flow, outflow, and jets, estimate strong magnetic fields, and unveil the radiation zone and particle acceleration processes in pulsars by studying X-ray polarization signatures.

To maximise the scientific outputs ISRO scheduled a one-day user meeting on May 25. This meeting has the involvement of approximately 20 institutes and universities from across the country. Almost 150 participants engaged in the meeting, with nearly 100 attending in-person and others joining through the online platform.

The launch of XPoSat is set to enhance our understanding of emission processes from various astronomical sources, which can offer unprecedented insights into the physics of objects such as black holes and neutron stars. The ISRO spacecraft will embark on its mission from the Satish Dhawan Space Centre in Sriharikota, propelled into space by the Polar Satellite Launch Vehicle (PSLV).