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SKYNET 4B (19687)
COSPAR: 1988-109A | Alt Name: Skynet 4B
Image
Additional Sources
Launch Details
Launch Date
December 11, 1988
Launch Site
FRGUI
Launch Pad
ELA2
Launch Vehicle
Ariane 44LP
Orbital Elements
NORAD ID
19687
International Designator
1988-109A
Epoch
Sat, 04 Jul 2026 06:00:42 GMT
Apogee
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Perigee
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Inclination
13.08°
Right Ascension
336.79°
Eccentricity
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Argument of Perigee
301.54°
Period
1444.67 min
Mean Motion
1.00 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
SKYNET 4B
Alternative Name
Skynet 4B
Type
Payload
Status
Non-operational
Owner
MOD
Country
United Kingdom
Constellation
N/A
Related Satellites
Major Events
N/A
Latest TLEs
1 19687U 88109A 26185.25048862 -.00000325 00000-0 00000-0 0 9995
2 19687 13.0847 336.7864 0003595 301.5400 237.0497 0.99676459118331
Source: Celestrak
Summary
SKYNET 4B is a military communication satellite operated by MOD (Ministry of Defence) and manufactured by BAES (British Aerospace). It was launched on December 11, 1988, from ELA2 at FRGUI using an Ariane 44LP launch vehicle. The satellite has dimensions of 2.1 meters in length and 1.9 meters in diameter with a span of 16 meters due to its solar arrays. It carries a total dry mass of 655 kilograms and had a launch mass of 767 kilograms. SKYNET 4B is equipped with two deployable solar arrays, batteries for power storage, and various transponders including 4 SHF (Super High Frequency), 2 UHF (Ultra High Frequency), and 2 C-band. The satellite's expected lifetime was six years and it was designed to support military communication needs. Its shape can be described as a box with two panels, and it has an RCS value of 2.3056.
Physical Characteristics
Length
2.1
Diameter
1.9
Span
16
Dry Mass
655
Launch Mass
767
Shape
Box + 2 Pan
Radar Cross Section
2.3056
Visual Magnitude
Unknown
Color
Unknown
Material Composition
Unknown
Technical Details
Payload
Skynet 4B
Purpose
Military communication
Mission
Military communication
Manufacturer
BAES
Life Expectancy
6 years
Bus
ECS
Configuration
ECS-Bus
Motor
TE-M-700-19
Equipment
4 SHF transponders (all), 2 UHF transponders (all), 2 C-band transponders (#D-F)
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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