OV1-4, 2121
Orbit data source: Space-Track
OV1-4, 2121 is a payload satellite owned by USAF OAR (US) in LEO that was launched on Wed, 30 Mar 1966 UTC via an ATLAS D launch vehicle from the Air Force Western Test Range (AFWTR). 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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2121 intel report (Beta)
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Edit Public Description
Identifier
Orbit
Country
USRelated business
Manufacturer
GD/Convair
Mission
Spacecraft
Bus & Motor
OV1, Unknown motor
Mass
87 kg wet, 87 kg dry
Launch date (UTC)
Launch vehicle
Launch site
Object type
Shape & HBR
Unknown
Radar Cross Section
Medium (>0.1 m² and <1 m²)
Expand to show TLE details & historyLast TLE update: 10 hours ago
TLE from 10 hours ago
0 OV1-4
1 2121U 66025A 25317.00007549 .00000387 00000-0 99177-4 0 9993
2 2121 144.5063 356.9809 0083947 262.4704 96.6431 13.87289674 21105Epoch: 2025-11-13T00:00Z
TLE epoch observation values (Epoch: 2025-11-13T00:00:06.522Z)
Latitude
-0.00001°
Longitude
-55.41048°
Altitude
944.778 km
Speed
7.377 km/s
True Right ascension
23h 47m 55s
True Declination
0° 00' 00"
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
06:17:18
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
1,002.569 km
Perigee altitude
879.683 km
Semi-major axis
7,319.263 km
Eccentricity
0.00839
Inclination
144.5063°
RAAN
356.9809°
Arg. of periapsis
262.4704°
True anomaly
97.5974°
Mean anomaly
96.6431°
Eccentric anomaly
97.12037°
Mean motion
3.46611 °/min
Orbital period
103.86 mins
BSTAR
0.000099177
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Other satellites on launch #25 in the year 1966 (1966-03-30 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.OV1-4 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. |
|---|---|---|---|---|---|---|---|
| 8 mins | 2025-11-13 17:50:43.241Z | 108.007° ESE | 2025-11-13 17:54:43.241Z | 153.688° SSE | 19.518° | 2025-11-13 17:58:43.241Z | 198.226° SSW |
| 9 mins | 2025-11-13 19:28:43.241Z | 98.887° ESE | 2025-11-13 19:32:43.241Z | 153.996° SSE | 34.034° | 2025-11-13 19:37:43.241Z | 230.405° WSW |
| 10 mins | 2025-11-13 21:06:43.241Z | 100.943° ESE | 2025-11-13 21:11:43.241Z | 194.422° SSW | 40.364° | 2025-11-13 21:16:43.241Z | 255.299° W |
| 9 mins | 2025-11-13 22:45:43.241Z | 121.982° SE | 2025-11-13 22:49:43.241Z | 197.551° SSW | 38.341° | 2025-11-13 22:54:43.241Z | 264.641° W |
| 8 mins | 2025-11-14 00:24:43.241Z | 156.576° SSE | 2025-11-14 00:27:43.241Z | 199.885° SSW | 26.722° | 2025-11-14 00:32:43.241Z | 261.294° W |
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 ascending order |
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CAUTION: Conjunctions in this section are generated from low-fidelity TLE screenings
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