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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Edit Public Description
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: 12 hours ago
TLE from 12 hours ago
0 COSMOS 2166
1 21780U 91077B 25259.23205170 .00000040 00000-0 16130-3 0 9993
2 21780 82.5961 60.9952 0004163 68.4680 104.2579 12.63439036560576Epoch: 2025-09-16T05:34Z
TLE epoch observation values (Epoch: 2025-09-16T05:34:09.266Z)
Latitude
7.09964°
Longitude
161.1085°
Altitude
1,411.676 km
Speed
7.155 km/s
True Right ascension
16h 00m 17s
True Declination
7° 03' 40"
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
09:53:44
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
1,409.341 km
Perigee altitude
1,402.86 km
Semi-major axis
7,784.237 km
Eccentricity
0.00042
Inclination
82.5961°
RAAN
60.9952°
Arg. of periapsis
68.468°
True anomaly
104.30413°
Mean anomaly
104.2579°
Eccentric anomaly
104.28102°
Mean motion
3.16023 °/min
Orbital period
113.92 mins
BSTAR
0.0001613
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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. |
|---|---|---|---|---|---|---|---|
| 5 mins | 2025-09-16 20:30:36.536Z | 40.351° NE | 2025-09-16 20:32:36.536Z | 54.765° ENE | 11.491° | 2025-09-16 20:35:36.536Z | 76.589° E |
| 15 mins | 2025-09-16 22:22:36.536Z | 359.296° N | 2025-09-16 22:29:36.536Z | 74.086° E | 42.51° | 2025-09-16 22:37:36.536Z | 161.456° S |
| 10 mins | 2025-09-17 00:19:36.536Z | 316.665° NNW | 2025-09-17 00:23:36.536Z | 281.336° WNW | 22.275° | 2025-09-17 00:29:36.536Z | 231.746° WSW |
| 15 mins | 2025-09-17 11:09:36.536Z | 170.876° S | 2025-09-17 11:16:36.536Z | 92.964° ESE | 42.578° | 2025-09-17 11:24:36.536Z | 13.247° NNE |
| 11 mins | 2025-09-17 13:07:36.536Z | 250.843° W | 2025-09-17 13:12:36.536Z | 296.947° NW | 22.896° | 2025-09-17 13:18:36.536Z | 344.397° N |
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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