Indian Remote Sensing satellite-P4
Mission typeEarth observation
COSPAR ID1999-029A Edit this at Wikidata
SATCAT no.25756
Mission duration5 years (planned)
11 years (achieved)
Spacecraft properties
ManufacturerIndian Space Research Organisation
Launch mass1,050 kg (2,310 lb)
Dimensions2.80 m x 1.98 m x 2.57 m
Power750 watts
Start of mission
Launch date26 May 1999, 06:22 UTC
RocketPolar Satellite Launch Vehicle, PSLV-C2
Launch siteSatish Dhawan Space Centre, First Launch Pad (FLP)
ContractorIndian Space Research Organisation
Entered serviceAugust 1999
End of mission
Deactivated8 August 2010
Orbital parameters
Reference systemGeocentric orbit[2]
RegimeSun-synchronous orbit
Perigee altitude719 km (447 mi)
Apogee altitude730 km (450 mi)
Period99.0 minutes
Multi-frequency Scanning microwave radiometer (MSMR)
Ocean Colour Monitor (OCM) [3]

Oceansat-1 or IRS-P4 was the first Indian satellite built primarily for ocean applications. It was a part of the Indian Remote Sensing Programme satellite series. The satellite carried an Ocean Colour Monitor (OCM) and a Multi-frequency Scanning Microwave Radiometer (MSMR) for oceanographic studies. Oceansat-1 thus vastly augment the IRS satellite system of Indian Space Research Organisation (ISRO) comprising four satellites, IRS-1B, IRS-1C, IRS-P3 and IRS-1D and extend remote sensing applications to several newer areas.[4]


Oceansat-1 was launched by the Indian Space Research Organisation's PSLV-C2 along with the DLR-Tubsat of Germany and Kitsat-3 of South Korea on 26 May 1999 from the Satish Dhawan Space Centre First Launch Pad of Satish Dhawan Space Centre in Sriharikota, India. It was the third successful launch of Polar Satellite Launch Vehicle (PSLV).[5] It was the 8th satellite of the Indian Remote Sensing Programme (IRS) satellite series of India. Oceansat-1 was operated in a Sun-synchronous orbit. On 26 May 1999, it had a perigee of 719 km (447 mi), an apogee of 730 km (450 mi), an inclination of 98.4°, and an orbital period of 99.0 minutes.[2]


Oceansat-1 carried two instruments:


Although initially launched with a lifespan of 5 years, Oceansat-1 completed its mission on 8 August 2010, after serving for 11 years.[5]


  1. ^ a b c "IRS-P4 (Oceansat-1)". Gunter's Space Page. 7 July 2020. Retrieved 13 May 2021.
  2. ^ a b "Trajectory: IRS-P4 1999-029A". NASA. 27 April 2021. Retrieved 13 May 2021. Public Domain This article incorporates text from this source, which is in the public domain.
  3. ^ "Ocean Colour Monitor of IRS-P4 Satellite Tested". ISRO. 3 June 1999. Retrieved 13 May 2021.
  4. ^ "Oceansat (IRS-P4)". ISRO. 26 May 1999. Retrieved 13 May 2021.
  5. ^ a b "IRS-P4 OceanSat". ISRO. Archived from the original on 21 January 2013. Retrieved 13 May 2021.
  6. ^ a b Sastry, Hari Ram Subrahmanya; Ebenezer, D. D.; Sundaram, T. V. S. (2002). Proceedings of the International conference on Sonar Sensors of Systems, Vol. 2. Allied Publishers. p. 635. ISBN 978-81-7764-382-4.
  7. ^ a b "Display: IRS-P4 1999-029A". NASA. 27 April 2021. Retrieved 13 May 2021. Public Domain This article incorporates text from this source, which is in the public domain.
  8. ^ Mather, Paul; Magaly Koch (29 December 2010). Computer Processing of Remotely-Sensed Images: An Introduction. John Wiley and Sons. p. 45. ISBN 978-0-470-66650-0.
  9. ^ Recent Advances In Environmental Science. Discovery Publishing House. 1 January 2003. p. 350. ISBN 978-81-7141-679-0.