Space Brief 4 Dec 2025
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IRS-P4 (OCEANSAT-1) (25758)
COSPAR: 1999-029C | Alt Name: Oceansat
Image
Additional Sources
Launch Details
Launch Date
May 26, 1999
Launch Site
SRILR
Launch Pad
FLP
Launch Vehicle
PSLV
Orbital Elements
NORAD ID
25758
International Designator
1999-029C
Epoch
Sat, 04 Jul 2026 03:49:25 GMT
Apogee
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Perigee
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Inclination
97.97°
Right Ascension
157.34°
Eccentricity
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Argument of Perigee
95.47°
Period
98.95 min
Mean Motion
14.55 rev/day
Latitude
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Longitude
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Altitude
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Velocity
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Polar Plot
3D Visualization
Basic Satellite Info
Name
IRS-P4 (OCEANSAT-1)
Alternative Name
Oceansat
Type
Payload
Status
Non-operational
Owner
ISRO
Country
India
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 25758U 99029C 26185.15931737 .00000466 00000-0 11741-3 0 9997
2 25758 97.9703 157.3419 0004287 95.4666 264.7021 14.55291307436586
Source: Celestrak
Summary
IRS-P4 (OCEANSAT-1), also known as Oceansat, is an Earth observation satellite operated by ISRO and manufactured by ISAC/HAL. It was launched on May 26, 1999, from SRILR using a PSLV launch vehicle. The spacecraft measures 2.8 meters in length with a diameter of 2 meters and a span of 11.7 meters. Its dry mass is 952 kg and it had a launch mass of 1036 kg. It uses two deployable solar arrays for power generation along with batteries. Equipped with OCM and MSMR equipment, its mission focuses on Earth observation with an expected lifetime of 5 years. The satellite's shape consists of a box configuration with two panels and has a radar cross-section (RCS) value of 3.4542.
Physical Characteristics
Length
2.8
Diameter
2
Span
11.7
Dry Mass
952
Launch Mass
1036
Shape
Box + 2 Pan
Radar Cross Section
3.4542
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
IRS-P4
Purpose
Earth observation
Mission
Earth observation
Manufacturer
ISAC/HAL
Life Expectancy
5 years
Bus
IRS
Configuration
IRS-1 Bus
Motor
AOCS
Equipment
OCM, MSMR
Power System
2 deployable solar arrays, batteries
ADCS
Unknown
Transmitter Frequency
Unknown
Map
Next Pass
Azimuth Elevation Time (Local)
Start Azimuth
Max Elevation
Stop Azimuth
Time Until
Pass Duration
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