May 26, 1999


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


प्रमोचन भार / Launch Mass: 
1050 kg
आयाम / Dimension: 
2.8m x 1.98m x 2.57m
मिशन कालावधि / Mission Life : 
August 8, 2010
शक्ति / Power: 
750 W
प्रमोचक राकेट / Launch Vehicle: 
उपग्रह का प्रकार / Type of Satellite: 
Earth Observation
निर्माता / Manufacturer: 
स्‍वामी / Owner: 
अनुप्रयोग / Application: 
Earth Observation
कक्षा का प्रकार / Orbit Type: