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INMARSAT 2-F4 (21940)
COSPAR: 1992-021B | Alt Name: INMARSAT II F-4
Image
Additional Sources
Launch Details
Launch Date
April 15, 1992
Launch Site
FRGUI
Launch Pad
ELA2
Launch Vehicle
Ariane 44L
Orbital Elements
NORAD ID
21940
International Designator
1992-021B
Epoch
Fri, 03 Jul 2026 10:15:59 GMT
Apogee
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Perigee
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Inclination
12.17°
Right Ascension
15.59°
Eccentricity
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Argument of Perigee
165.71°
Period
1470.23 min
Mean Motion
0.98 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
INMARSAT 2-F4
Alternative Name
INMARSAT II F-4
Type
Payload
Status
Non-operational
Owner
INMAR
Country
INMARSAT
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 21940U 92021B 26184.42777575 -.00000125 00000-0 00000-0 0 9994
2 21940 12.1735 15.5948 0006700 165.7141 202.6291 0.97943801 50814
Source: Celestrak
Summary
INMARSAT 2-F4 (OBJECT_ID: 1992-021B) is a communication satellite built by BAES and launched on April 15, 1992, from ELA2 in French Guiana using an Ariane 44L launch vehicle. The satellite has a Eurostar 1000 configuration with dimensions of 2.4 meters in length, 1.5 meters in diameter, and spans 14.9 meters when its solar arrays are deployed. It weighs 624 kilograms dry and had a launch mass of 1310 kilograms. The satellite is equipped with four L-band transponders (with an additional two backup) and one C-band transponder (with an additional backup), powered by two deployable solar arrays and batteries. INMARSAT 2-F4 has a planned lifetime of ten years, serving communication purposes for its owner, INMAR, operating in the I-INM country category with the RCS value at 13.9974.
Physical Characteristics
Length
2.4
Diameter
1.5
Span
14.9
Dry Mass
624
Launch Mass
1310
Shape
Box + 2 Pan
Radar Cross Section
13.9974
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
INMARSAT II F-4
Purpose
Communication
Mission
Communication
Manufacturer
BAES
Life Expectancy
10 years
Bus
Eurostar 1000
Configuration
Eurostar-1000
Motor
R-4D-11
Equipment
4 (+2) L-band transponders, 1 (+1) C-band transponders
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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