On 22 June 2026 ISRO issued a second Announcement of Opportunity inviting researchers from Indian institutes to propose analyses of XPoSat data. ISRO has released XPoSat scientific data into the public domain; findings have been published in international peer‑reviewed journals.
Mission Overview
- XPoSat: India’s first dedicated X‑ray polarimetry satellite; launched 1 Jan 2024; near‑equatorial orbit at 650 km.
- Payloads: POLIX — Polarimeter Instrument in X‑rays; XSPECT — X‑ray Spectroscopy & Timing.
Scientific Purpose
- Objective: Measure X‑ray polarisation to probe emission geometry and magnetic fields in black holes, neutron stars and active galactic nuclei.
- Method: X‑ray polarimetry determines degree and angle of photon electric‑field vectors; complements spectroscopy and timing for source diagnostics.
Second AO: Scope & Deadlines
- Eligibility: Indian scientists affiliated to institutes, universities or colleges within India.
- Scope: AO‑2 accepts only XSPECT‑based proposals.
- Observation window: September 2026 to March 2027.
- Submission deadline: 25 July 2026.
Data Access & Archive
- Proprietary period: Six months for proposers; thereafter observations released to registered users via the Indian Space Science Data Centre (ISSDC).
- Availability: Mission data accessible in the public domain for global scientific use through ISSDC.
IASPOINT Booster Facts
- ISSDC: Provides calibrated products, observation logs and download services for ISRO missions.
- Complementarity: Polarimetry fills gaps left by pure spectroscopy/timing in constraining emission models.
