October 13, 2025
On October 13, 2025, ISRO organised a National Meet on XPoSat mission and released the scientific data from the mission to the scientific community. XPoSat is India’s space-based X-Ray astronomy observatory in a Low Earth Orbit (LEO) of around 650 km altitude and 6 degrees of inclination. It carries two scientific payloads, viz. POLIX, aimed at measuring the degree and angle of polarization in medium X-ray energy range of 8-30 keV, and XSPECT, which will provide spectroscopic information in the energy range of 0.8-15 keV. The POLIX payload is developed by Raman Research Institute, Bengaluru in close coordination with ISRO, while the XSPECT payload is developed by U R Rao Satellite Centre (URSC), ISRO, Bengaluru. The spacecraft was launched on Jan 1, 2024 by ISRO rocket PSLV-C 58 from Satish Dhawan Space Centre (SDSC), SHAR/ISRO. XPoSat is intended to be used as a proposal-driven space-based X-Ray astronomy observatory, like India’s multi-wavelength space-based astronomical observatory AstroSat.
Chairman, ISRO / Secretary, DOS releasing the first dataset of XPoSat to the scientific community, and opening up the opportunity for Guest Observation with XPoSat
The maiden datasets from XPoSat (amounting to about 143 GB), relevant tools, along with the guest observer opportunity to use the XPoSat for scientific observations by Indian X-ray Astronomy Community were released by Dr. V. Narayanan, Chairman, ISRO / Secretary, DOS, in ISRO Headquarters, Bengaluru, in the presence of a gathering of Astronomers, mission planners, academicians and students from different parts of the country. The data release event was followed by an appraisal meet on the performance of the XPoSat mission, and its scientific payloads. The meet, covering technical sessions on XSPECT and POLIX, was attended by about 175 members from Indian academia, research institutes, as well as from the ISRO/DOS community. The participants included more than 50 members from the Indian academia, research institutes including faculties, researchers and students, representing around 15 universities/institutes/colleges across the country.
During the inaugural address, Chairman, ISRO / Secretary, DOS mentioned about the opportunities opened up by XPoSat to build even more sophisticated astronomical observatories in near future. Shri A. S. Kiran Kumar, former Chairman, ISRO / Secretary, DOS, Member Space Commission, Chair, Apex Science Board, ISRO underscored the importance of engaging the student community to engage themselves in several space-based techniques to study astronomical sources and processes, in view of their potential contributions to the global mega projects in future. Dr. Tirtha Pratim Das, Director, Space Science Programme, ISRO Headquarters mentioned that XPoSat is India’s first step towards technically integrating the timing, spectroscopy and polarisation of X-Rays in the same observation platform to derive holistic information about astronomical X-Ray sources, which will eventually lead to enhanced capacity building in the country, both in science and space-borne instrumentation.
Participants of the XPoSat data release and performance appraisal national meet
The XPoSat datasets, as well as the supporting tools can be accessed from the portal of the Indian Space Science Data Centre (ISSDC). The following links may be accessed to explore the XPoSat data and the relevant tools (XPoSat Proposal Processing System and XPoViewer – the XPoSat Targets Visibility Analysis Tool).
https://pradan1.issdc.gov.in/x01 (to access XPoSat data)
https://xpps.issdc.gov.in/web (to access the XPoSat Proposal Processing System)
https://webapps.issdc.gov.in/XPoViewer (to access the XPoViewer)
The Announcement of Opportunity (AO) to propose astronomical observations through XPoSat