ASTRA 1B, 21139
Orbit data source: Space-Track
ASTRA 1B, 21139 is a payload satellite owned by SES (LU) in GEO that was launched on Sat, 02 Mar 1991 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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21139 intel report (Beta)
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Identifier
Orbit
Country
LU / SESRelated business
Manufacturer
GE/East Windsor
Mission
Non-operational Commercial Communications
Bus & Motor
AS5000, 2X LEROS 1
Mass
2,580 kg wet, 1,177 kg dry
Launch date (UTC)
Launch vehicle
Launch site
Object type
Shape & HBR
Hex Poly + 2 Pan, 12.2 m
Radar Cross Section
18.796 m², Large (>1 m²)
Expand to show TLE details & historyLast TLE update: 2 days ago
TLE from 2 days ago
0 ASTRA 1B
1 21139U 91015A 26171.34136207 -.00000010 00000-0 00000+0 0 9996
2 21139 13.3713 22.1973 0009200 12.2021 233.5444 0.98509364116310Epoch: 2026-06-20T08:11Z
TLE epoch observation values (Epoch: 2026-06-20T08:11:33.682Z)
Latitude
-12.186°
Longitude
-124.16794°
Altitude
36,313.494 km
Speed
3.055 km/s
True Right ascension
17h 49m 07s
True Declination
-12° 10' 27"
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
00:51:29
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
36,328.246 km
Perigee altitude
36,249.739 km
Semi-major axis
42,667.13 km
Eccentricity
0.00092
Inclination
13.3713°
RAAN
22.1973°
Arg. of periapsis
12.2021°
True anomaly
233.45966°
Mean anomaly
233.5444°
Eccentric anomaly
233.50203°
Mean motion
0.24627 °/min
Orbital period
1,461.84 mins
BSTAR
0
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Other satellites on launch #15 in the year 1991 (1991-03-02 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.ASTRA 1B Visibility forecast
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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. |
|---|---|---|---|---|---|---|---|
| 1440 mins | 2026-06-22 13:48:55.318Z | 218.446° SW | 2026-06-22 22:55:55.318Z | 238.865° WSW | 34.464° | 2026-06-23 13:48:55.318Z | 224.183° SW |
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21139 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
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CAUTION: Conjunctions in this section are generated from low-fidelity TLE screenings
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