XPoSat launch: what is ISRO's first mission of this yr
- ISRO recently achieved a major milestone with the successful launch of the X-ray Polarimeter Satellite (XPoSat) into a precise circular orbit of 650 km.
XPoSat
- It is the world's second satellite-based mission solely dedicated to making X-ray polarimetry measurements.
- It is positioned for observation from a low Earth orbit (~650 km, low inclination of ~6 degrees).
- It is designed to observe polarised X-rays emitted during specific celestial events, such as when magnetars or neutron stars pass through Earth's shadow during an eclipse period.
- It introduces X-ray polarisation measurements in the medium energy band (8-30 keV).
- This unexplored realm promises to enhance our understanding of celestial bodies like magnetars, black holes, and neutron stars.
Key Components and Objectives
- XPoSat features two payloads viz. Indian X-ray Polarimeter (POLIX) and X-ray Spectroscopy and Timing (XSPECT).
- Developed by the Raman Research Institute and UR Rao Satellite Centre in Bengaluru.
- These payloads aim to analyse the polarisation of X-rays from celestial sources.
- Anticipated mission life is around five years.
POLIX and XSPECT Payloads
- POLIX
- The world's first instrument operating in the medium X-ray energy band (8-30 keV).
- It includes a collimator and four X-ray proportional counter detectors to observe a variety of astronomical sources.
- XSPECT
- Engineered for fast timing and high spectroscopic resolution in the soft X-ray energy band (0.8-15 keV).
- This payload targets sources like X-ray pulsars, black hole binaries, low-magnetic field neutron stars, active galactic nuclei, and magnetars.
Global Context
- Compared to other X-ray polarimetry missions globally, XPoSat offers a unique contribution with its expanded observational energy band.
- It complements efforts like NASA's Imaging X-ray Polarimetry Explorer (IXPE).
- While X-ray polarimetry missions have been limited globally, the development of a market for cost-competitive solutions, remains a work in progress.
Future Prospects
- The success of XPoSat sets the stage for further technological evolution in the field, emphasising the need for sensitive and precise instruments for future missions.