SKYNET 4B, 19687
Orbit data source: Space-Track
SKYNET 4B, 19687 is a payload satellite owned by UK MoD (UK) in GEO that was launched on Sun, 11 Dec 1988 UTC via an ARIANE 44LP launch vehicle from the French Guiana (FRGUI). Payload-class satellites include a variety of spacecraft equipped with specific instruments for various scientific and technological missions. These include communications satellites like Starlink; space stations such as the ISS; scientific satellites like the Hubble; Earth observation satellites from companies like Planet Labs, Umbra, and HawkEye 360; GPS; miniature CubeSats for education and research; and military/defense satellites.
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19687 intel report (Beta)
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Edit Public Description
Identifier
Orbit
Country
UKRelated business
Manufacturer
BAe
Mission
Non-operational Defense Communications
Bus & Motor
ECS, TE-M-700-19
Mass
1,433 kg wet, 655 kg dry
Launch date (UTC)
Launch vehicle
Launch site
Object type
Shape & HBR
Hex Poly + 2 Pan, 8.0 m
Radar Cross Section
11.617 m², Large (>1 m²)
Expand to show TLE details & historyLast TLE update: 12 hours ago
TLE from 12 hours ago
0 SKYNET 4B
1 19687U 88109A 25287.91267459 -.00000199 00000-0 00000-0 0 9994
2 19687 13.3354 338.6459 0007512 263.2686 100.8212 0.99676977115728Epoch: 2025-10-14T21:54Z
TLE epoch observation values (Epoch: 2025-10-14T21:54:15.084Z)
Latitude
0.96439°
Longitude
-9.56038°
Altitude
35,959.721 km
Speed
3.068 km/s
True Right ascension
22h 50m 47s
True Declination
0° 57' 48"
Sunlit
Visualization orbit readout
Latitude
Unknown
Longitude
Unknown
Altitude
Unknown
Speed
Unknown
Apparent Right ascension
Unknown
Apparent Declination
Unknown
Sunlit
Visualization observer readout
Local Sidereal Time
04:52:27
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
35,986.954 km
Perigee altitude
35,923.352 km
Semi-major axis
42,333.29 km
Eccentricity
0.00075
Inclination
13.3354°
RAAN
338.6459°
Arg. of periapsis
263.2686°
True anomaly
100.90574°
Mean anomaly
100.8212°
Eccentric anomaly
100.86347°
Mean motion
0.24918 °/min
Orbital period
1,444.72 mins
BSTAR
0
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Other satellites on launch #109 in the year 1988 (1988-12-11 UTC)
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You can import UDL-sourced sensor .json files into the Sandbox to generate a visibility chart that accounts for multi-vendor sensor geometry.SKYNET 4B Visibility
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Span | Click to sort rows by Start time (UTC) header in descending order | Start Az. | Max El. time (UTC) | Max El. Az. | Max El. | End time (UTC) | End Az. |
|---|---|---|---|---|---|---|---|
| SKYNET 4B is likely not visible in the next few days. |
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19687 neighbors
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Co-orbital & Co-planar RSOs
Thresholds — Semi-major Axis: ±100 km, RAAN: ±3°, Inclination: ±5°
TCA is derived from TLE conjunctions
Click to sort rows by RSO header in ascending order | Click to sort rows by Country header in ascending order | Click to sort rows by Type header in ascending order | Click to sort rows by Inclination Δ header in ascending order | Click to sort rows by RAAN Δ header in ascending order | Click to sort rows by Coplanar Angle header in ascending order | Click to sort rows by SMA Δ header in ascending order | Click to sort rows by Orbital period header in ascending order | Click to sort rows by <5km Md TCA header in ascending order |
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CAUTION: Conjunctions in this section are generated from low-fidelity TLE screenings
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Click to sort rows by Secondary header in ascending order | Click to sort rows by Secondary name header in ascending order | Click to sort rows by Country header in ascending order | Click to sort rows by Owner header in ascending order | Click to sort rows by Obj. Type header in ascending order | Click to sort rows by Miss dist. header in ascending order | Click to sort rows by Rel. speed header in ascending order | Click to sort rows by Apr. angle header in ascending order | Click to sort rows by TCA header in ascending order |
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