COSMOS 2143, 21299
Orbit data source: Space-Track
COSMOS 2143, 21299 is a payload satellite owned by UNKS RF (CIS) in LEO that was launched on Thu, 16 May 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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21299 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: 2 days ago
TLE from 2 days ago
0 COSMOS 2143
1 21299U 91033A 26171.46754301 .00000036 00000-0 13980-3 0 9999
2 21299 82.5753 300.6555 0013573 49.7790 21.0789 12.63928984618985Epoch: 2026-06-20T11:13Z
TLE epoch observation values (Epoch: 2026-06-20T11:13:15.716Z)
Latitude
69.64224°
Longitude
-115.88717°
Altitude
1,408.935 km
Speed
7.167 km/s
True Right ascension
21h 24m 26s
True Declination
69° 32' 21"
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
02:14:52
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
1,414.651 km
Perigee altitude
1,393.525 km
Semi-major axis
7,782.225 km
Eccentricity
0.00136
Inclination
82.5753°
RAAN
300.6555°
Arg. of periapsis
49.779°
True anomaly
21.13493°
Mean anomaly
21.0789°
Eccentric anomaly
21.1069°
Mean motion
3.16146 °/min
Orbital period
113.87 mins
BSTAR
0.0001398
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Other satellites on launch #33 in the year 1991 (1991-05-16 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 2143 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. |
|---|---|---|---|---|---|---|---|
| 10 mins | 2026-06-22 18:34:05.290Z | 26.536° NE | 2026-06-22 18:39:05.290Z | 67.356° ENE | 18.613° | 2026-06-22 18:44:05.290Z | 106.288° ESE |
| 14 mins | 2026-06-22 20:28:05.290Z | 350.236° N | 2026-06-22 20:35:05.290Z | 219.242° SW | 44.547° | 2026-06-22 20:42:05.290Z | 178.887° S |
| 5 mins | 2026-06-22 22:26:05.290Z | 299.617° NW | 2026-06-22 22:28:05.290Z | 284.038° WNW | 13.959° | 2026-06-22 22:31:05.290Z | 261.184° W |
| 8 mins | 2026-06-23 07:24:05.290Z | 106.403° ESE | 2026-06-23 07:27:05.290Z | 81.741° E | 17.369° | 2026-06-23 07:32:05.290Z | 42.356° NE |
| 15 mins | 2026-06-23 09:14:05.290Z | 189.516° SSW | 2026-06-23 09:21:05.290Z | 265.07° W | 44.765° | 2026-06-23 09:29:05.290Z | 6.042° NNE |
| 7 mins | 2026-06-23 11:14:05.290Z | 272.278° WNW | 2026-06-23 11:17:05.290Z | 295.788° NW | 15.113° | 2026-06-23 11:21:05.290Z | 327.003° NNW |
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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