Mission typeOceanography
Earth observation
Remote sensing
COSPAR ID1999-029A
SATCAT no.25756
Mission durationPlanned: 5 years
Elapsed: 11 years and 2 months
Spacecraft properties
BusIRS-P3 [1]
Launch mass1050 kg
Dimensions2.8 x 1.98 x 2.57 m
Power750 watts
Start of mission
Launch date26 May 1999
Launch siteSriharikota, FLP
End of mission
Deactivated8 August 2010
Orbital parameters
Reference systemGeocentric [2]
Perigee altitude719 km
Apogee altitude730 km
Period99.0 minutes
Epoch26 May 1999
Ocean Colour Monitor (OCM) [3]
Multi-frequency Scanning microwave radiometer (MSMR)

Oceansat-1 or IRS-P4 was the first Indian satellite built specifically 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 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 German DLR-Tubsat and South Korean Kitsat-3 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 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 kilometres (447 mi), an apogee of 730 kilometres (450 mi), an inclination of 99.0°, and an orbital period of 99.0 minutes.[2]


Oceansat-1 carried two payloads:

The first, the Ocean Colour Monitor (OCM), is a solid state camera literally designed primarily to monitor the colour of the ocean,[6] thereby useful for documenting chlorophyll concentration, phytoplankton blooms, atmospheric aerosols and particulate matter.[1] It is capable of detecting eight spectrums ranging from 400 nm to 885 nm, all in the visible or near infrared spectrums.[7] OCM monitor globally potential fishery zones, ocean currents, and pollution and sediment inputs in the coastal zones. It operates on eight wavelength bands, providing data with a swath width of 1420 km and at a resolution of 350 metres.[8]

The second, the Multi-frequency Scanning Microwave Radiometer (MSMR), collects data by measuring microwave radiation passing through the atmosphere over the ocean.[9] This offers information including sea surface temperature, wind speed, cloud water content, and water vapour content.[1][9] MSMR monitor at 6.6 GHz.[8]

Mission completed

Although initially launched with a lifespan of 5 years, Oceansat-1 completed its mission on 8 August 2010, after serving for 11 years and 2 months.[5]


  1. ^ a b c "IRS-P4 - Gunter's Space Page". Gunter's Space Page. Retrieved 27 May 2013.
  2. ^ a b "Oceansat: Trajectory 1999-029A". nssdc.gsfc.nasa.gov. NASA. 17 April 2020. Retrieved 12 May 2020. This article incorporates text from this source, which is in the public domain.
  3. ^ "Ocean Colour Monitor of IRS-P4 Satellite Tested". Indian Space Research Organisation. 3 June 1999.
  4. ^ https://www.isro.gov.in/Spacecraft/oceansatirs-p4
  5. ^ a b "IRS-P4 - ISRO page". Indian Space Research Organisation. Archived from the original on 21 January 2013. Retrieved 27 May 2013.
  6. ^ 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.
  7. ^ Recent Advances In Environmental Science. Discovery Publishing House. 1 January 2003. p. 350. ISBN 978-81-7141-679-0.
  8. ^ a b "Oceansat: Display 1999-029A". nssdc.gsfc.nasa.gov. NASA. 17 April 2020. Retrieved 12 May 2020. This article incorporates text from this source, which is in the public domain.
  9. ^ a b Sastry, Hari Ram Subrahmanya; Ebenezer, D. D.; Sundaram, T. V. S. (2002). Proceedings of theInternational conference on SonarSensors of Systems, Vol. 2. Allied Publishers. p. 635. ISBN 978-81-7764-382-4.

External links

  • Indian Space Research Organisation: IRS-P4