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: 13 hours ago
TLE from 13 hours ago
0 COSMOS 2166
1 21780U 91077B 25358.77242046 .00000013 00000-0 12767-4 0 9998
2 21780 82.5998 357.5275 0003244 174.5045 0.3835 12.63443477573144Epoch: 2025-12-24T18:32Z
TLE epoch observation values (Epoch: 2025-12-24T18:32:17.127Z)
Latitude
4.9893°
Longitude
165.27266°
Altitude
1,408.461 km
Speed
7.158 km/s
True Right ascension
11h 47m 31s
True Declination
4° 57' 43"
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
06:59:08
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
1,408.607 km
Perigee altitude
1,403.557 km
Semi-major axis
7,784.219 km
Eccentricity
0.00032
Inclination
82.5998°
RAAN
357.5275°
Arg. of periapsis
174.5045°
True anomaly
0.38375°
Mean anomaly
0.3835°
Eccentric anomaly
0.38362°
Mean motion
3.16024 °/min
Orbital period
113.92 mins
BSTAR
0.000012767
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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 | 2025-12-25 11:19:17.786Z | 2.053° NNE | 2025-12-25 11:27:17.786Z | 83.898° E | 38.514° | 2025-12-25 11:34:17.786Z | 150.984° SSE |
| 12 mins | 2025-12-25 13:16:17.786Z | 324.864° NNW | 2025-12-25 13:21:17.786Z | 278.006° WNW | 27.294° | 2025-12-25 13:28:17.786Z | 218.847° SW |
| 14 mins | 2025-12-26 00:07:17.786Z | 160.424° S | 2025-12-26 00:14:17.786Z | 83.802° E | 38.527° | 2025-12-26 00:21:17.786Z | 18.412° NNE |
| 13 mins | 2025-12-26 02:03:17.786Z | 234.445° WSW | 2025-12-26 02:09:17.786Z | 289.977° WNW | 27.797° | 2025-12-26 02:16:17.786Z | 349.142° 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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