PSLV-C58 XPoSat mission
16 Jan 2024 2 mins Download PDF
Context: The Indian Space Research Organisation (ISRO) kicked off the new year with the launch of the PSLV-C58 X-ray Polarimeter Satellite (XPoSat) on January 1, 2024.
- On January 1, 2024, the PSLV-C58 mission achieved success, placing the primary satellite, XPoSat, into the intended orbit of 650 km with a 6-degree inclination
- The successful launch of XPoSat makes India the second nation globally to send an observatory for studying astronomical Sources, including black holes and neutron stars
- PSLV Orbital Experimental Module-3 (POEM-3): During the mission, the POEM-3 experiment was executed to meet the objective of deploying 10 other payloads
- PS4 Stage Operations: After injecting XPoSat into a 650 km, 6-degree orbit, the PS4 stage was lowered to a 350 km, ~9.6-degree orbit by restarting it twice. The PS4 stage serves as a 3-axis stabilized orbital platform for conducting experiments with space-qualify systems
- Launch of 10 Payloads: The PSLV also launched 10 payloads developed by start-ups, educational institutions, and ISRO centers, including Radiation Shielding Experimental Module (RSEM), Women Engineered Satellite (WESAT), BeliefSat-0 Amateur radio satellite, Green Impulse TrAnsmitter (GITA), LEAP-TD, RUDRA 0.3 HPGP, ARKA-200, Dust Experiment (DEX), ISRO Fuel cell Power System (FCPS), and Si-based High Energy cell
XPoSat
- XPoSat, or X-ray Polarimeter Satellite, is India's pioneering mission in polarimetry designed to study astronomical Sources in extreme conditions.
- It represents the world's second X-ray polarimetry mission after NASA's Imaging X-ray Polarimetry Explorer (IXPE) launched in 2021.
- A collaborative effort between ISRO and the Raman Research Institute (RRI) in Bengaluru, Karnataka.
Scientific Payloads:
- XPoSat carries two primary scientific payloads: Polarimeter Instrument in X-rays (POLIX) and X-ray Spectroscopy and Timing (SPECT).
- POLIX measures polarimetry parameters like degree and angle of polarization in the medium X-ray energy range (8-30 keV) from astronomical Sources.
- SPECT provides timing and spectroscopic information within the energy range of 0.8-15 keV for X-ray photons.
Significance in Astronomical Understanding:
- Polarimetry measurements serve as a valuable diagnostic tool for understanding emission processes from various astronomical Sources.
- Complex emission mechanisms from Sources like black holes, neutron stars, active galactic nuclei, and pulsar wind nebulae pose challenges to current understanding.
- Combining polarimetric observations with spectroscopic and timing data aims to overcome limitations in comprehending these astronomical emission processes.
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