26 May 1999
OCEANSAT was launched
OCEANSAT, the first satellite built chiefly for oceanic applications was launched by the Indian Space Research Organisation (ISRO) on 26 May 1999.
- OCEANSAT, also known as IRS-P4 or OCEANSAT-1, was launched by ISRO from its SHAR Centre in Sriharikota.
- The satellite weighed 1050 kg and was launched by a Polar Satellite Launch Vehicle (PSLV-C2).
- The satellite was placed in a polar sun-synchronous orbit at a distance of 720 km.
- It was the first Indian satellite that had a chief objective of conducting oceanographic studies.
- The payload it carried were an Ocean Colour Monitor (OCM) and a Multi – frequency Scanning Microwave Radiometer (MSMR).
- The OCM was a solid-state camera which operated in the push-broom scanning mode. It used linear array CCD’s as detectors in order to create ocean biological parameters.
- The OCM had eight spectral bands for measuring biological and physical oceanographic parameters. The MSMR operated at 21, 18, 10.65 and 6.6 GHz frequencies with H and V polarisations. The spatial resolutions it operated at the respective frequencies were 50 km, 50 km, 75 km and 150 km.
- The size of the satellite was 2.8 m X 1.98 m X 2.57 m.
- It had an inclination of 98.28 degrees and a Period of 99.31 minutes. The Repetitivity cycle was 2 days.
- When fully deployed, the OCEANSAT had a dimension of 11.67 m.
- The attitude and orbit control were achieved by 3-axis body-stabilised using Reaction Wheels, Hydrazine Thrusters and Magnetic Torques.
- The satellite’s power was supplied by a solar array having a size of 9.6 m2 that generated 750 W. It also had two 21 Ah Ni-Cd batteries.
- The OCEANSAT boosted India’s IRS satellite system. The other satellites in this series are: IRS-1B, IRS-1C, IRS-P3 and IRS-1D.
- The satellite completed its mission on 8th August 2010 after serving for 11 years and 2 months.
- The next in the series, OCEANSAT-2 was launched in 2009 and is now operating.