IRS-P4 (OCEANSAT) is the first satellite primarily built for Ocean applications, weighing 1050 kg placed in a Polar Sun Synchronous orbit of 720 km, launched by PSLV-C2 from SHAR Centre, Sriharikota on May 26, 1999.

This satellite carries Ocean Colour Monitor (OCM) and a Multi - frequency Scanning Microwave Radiometer (MSMR) for oceanographic studies. IRS-P4 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.

Mission completed on August 8, 2010 after serving for 11 years and 2 months.

 

Launch date	May 26, 1999
Launch site	SHAR, Sriharikota
Launch vehicle	PSLV - C2
Orbit	Polar Sun Synchronous
Altitude	720 km
Inclination	98.28 deg
Period	99.31 min
Local time of Eq. crossing	12 noon
Repetitivity cycle	2 days
Size	2.8m x 1.98m x 2.57m
Mass at lift off	1050 kg
Length when fully deployed	11.67 m
Attitude and Orbit Control	3-axis body-stabilised using Reaction Wheels, Magnetic Torquers and Hydrazine Thrusters
Power	9.6 Sq.m Solar Array generating 750w Two 21 Ah Ni-Cd Batteries
Mission Completed On	August 8, 2010