COSMOS 2166, 21780
Orbit data source: Space-Track
COSMOS 2166, 21780 is a payload satellite owned by UNKS RF (CIS) in LEO that was launched on Tue, 12 Nov 1991 UTC via a TSIKLON-3 launch vehicle from the Plesetsk Missile And Space Complex (PKMTR). 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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21780 intel report (Beta)
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Identifier
Orbit
Country
CISRelated business
Manufacturer
NPO PM
Mission
Defense Communications
Bus & Motor
STRELA-3, Unknown motor
Mass
225 kg wet, 225 kg dry
Launch date (UTC)
Launch vehicle
Launch site
Object type
Shape & HBR
Cyl, 0.8 m
Radar Cross Section
1.257 m², Large (>1 m²)
Expand to show TLE details & historyLast TLE update: 23 hours ago
TLE from 23 hours ago
0 COSMOS 2166
1 21780U 91077B 26125.66394856 .00000029 00000-0 10130-3 0 9994
2 21780 82.5966 273.4169 0002529 245.2701 125.9865 12.63447883589809Epoch: 2026-05-05T15:56Z
TLE epoch observation values (Epoch: 2026-05-05T15:56:05.155Z)
Latitude
11.13998°
Longitude
172.31881°
Altitude
1,411.886 km
Speed
7.155 km/s
True Right ascension
18h 19m 30s
True Declination
11° 04' 50"
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
22:23:42
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
1,408.032 km
Perigee altitude
1,404.095 km
Semi-major axis
7,784.201 km
Eccentricity
0.00025
Inclination
82.5966°
RAAN
273.4169°
Arg. of periapsis
245.2701°
True anomaly
126.00995°
Mean anomaly
125.9865°
Eccentric anomaly
125.99822°
Mean motion
3.16025 °/min
Orbital period
113.91 mins
BSTAR
0.0001013
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Other satellites on launch #77 in the year 1991 (1991-11-12 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.COSMOS 2166 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. |
|---|---|---|---|---|---|---|---|
| 15 mins | 2026-05-06 20:59:20.509Z | 2.758° NNE | 2026-05-06 21:06:20.509Z | 65.759° ENE | 38.266° | 2026-05-06 21:14:20.509Z | 151.337° SSE |
| 12 mins | 2026-05-06 22:55:20.509Z | 328.888° NNW | 2026-05-06 23:01:20.509Z | 275.047° WNW | 27.47° | 2026-05-06 23:07:20.509Z | 222.004° SW |
| 14 mins | 2026-05-07 09:47:20.509Z | 159.459° S | 2026-05-07 09:53:20.509Z | 101.464° ESE | 38.222° | 2026-05-07 10:01:20.509Z | 17.98° NNE |
| 12 mins | 2026-05-07 11:43:20.509Z | 235.547° WSW | 2026-05-07 11:49:20.509Z | 293.227° NW | 27.883° | 2026-05-07 11:55:20.509Z | 345.888° N |
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 descending order |
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CAUTION: Conjunctions in this section are generated from low-fidelity TLE screenings
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