IRS-P3

An Earth observation and X-ray astronomy satellite launched on the third PSLV development flight in March 1996, carrying an imaging spectrometer from Germany's DLR.

No longer operational, according to the public satellite catalogue.

What it did

IRS-P3 had three jobs: remote sensing of Earth's resources, X-ray astronomy, and regular calibration of the tracking radars used for PSLV launches. It carried:

  • WiFS, a wide-field camera like the one on IRS-1C, with an extra short-wave infrared band.
  • MOS, the Modular Opto-electronic Scanner, an experimental imaging spectrometer supplied by DLR in Berlin.
  • IXAE, the Indian X-ray Astronomy Experiment, built by ISRO with the Tata Institute of Fundamental Research, Mumbai.
  • A C-band transponder for radar calibration.

Spacecraft

IRS-P3 weighed 920 kg and had 817 watts of power. It was three-axis stabilised and based on the IRS-P2 design.

Launch and mission

PSLV-D3 launched IRS-P3 from SHAR Centre, Sriharikota, on 21 March 1996. It flew a circular polar sun-synchronous orbit at 817 km, crossing the equator at 10:30 a.m.; WiFS covered the same ground every 5 days.

The mission ended in January 2006, after 9 years and 10 months.

Sources

  1. IRS-P3 — satellite catalogue record (NORAD 23827) — CelesTrak
  2. IRS-P3 — ISRO
  3. IRS P3 — Gunter's Space Page
  4. List of DoS/ISRO satellites launched so far (10 April 2025) — ISRO