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
Defense Science
Bus & Motor
OV1, Unknown motor
Mass
87 kg wet, 87 kg dry
Launch date (UTC)
Launch vehicle
Launch site
Object type
Shape & HBR
Domed Cyl, 0.7 m
Radar Cross Section
0.946 m², Medium (>0.1 m² and < 1m²)
Expand to show TLE details & historyLast TLE update: 21 hours ago
TLE from 21 hours ago
0 OV1-4
1 02121U 66025A 25260.35152517 .00000303 00000-0 30703-4 0 9992
2 02121 144.5046 72.2286 0083521 218.3134 141.1580 13.87274934 13237Epoch: 2025-09-17T08:26Z
TLE epoch observation values (Epoch: 2025-09-17T08:26:11.774Z)
Latitude
-0.00002°
Longitude
-50.84914°
Altitude
985.002 km
Speed
7.337 km/s
True Right ascension
04h 48m 54s
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
22:40:33
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
1,002.309 km
Perigee altitude
880.046 km
Semi-major axis
7,319.314 km
Eccentricity
0.00835
Inclination
144.5046°
RAAN
72.2286°
Arg. of periapsis
218.3134°
True anomaly
141.7534°
Mean anomaly
141.158°
Eccentric anomaly
141.45618°
Mean motion
3.46607 °/min
Orbital period
103.86 mins
BSTAR
0.000030703
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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. |
|---|---|---|---|---|---|---|---|
| 10 mins | 2025-09-18 07:11:24.052Z | 111.83° ESE | 2025-09-18 07:16:24.052Z | 176.764° S | 39.223° | 2025-09-18 07:21:24.052Z | 262.292° W |
| 8 mins | 2025-09-18 08:51:24.052Z | 147.301° SSE | 2025-09-18 08:55:24.052Z | 208.93° SW | 29.273° | 2025-09-18 08:59:24.052Z | 259.618° W |
| 4 mins | 2025-09-18 10:32:24.052Z | 198.667° SSW | 2025-09-18 10:33:24.052Z | 209.779° SW | 13.961° | 2025-09-18 10:36:24.052Z | 241.128° WSW |
| 4 mins | 2025-09-19 02:31:24.052Z | 131.165° SE | 2025-09-19 02:33:24.052Z | 155.279° SSE | 15.051° | 2025-09-19 02:35:24.052Z | 177.949° S |
| 9 mins | 2025-09-19 04:07:24.052Z | 101.04° ESE | 2025-09-19 04:11:24.052Z | 157.734° S | 30.931° | 2025-09-19 04:16:24.052Z | 225.412° WSW |
| 6 mins | 2025-09-19 05:45:24.052Z | 99.5° ESE | 2025-09-19 05:49:24.052Z | 154.667° SSE | 39.459° | 2025-09-19 05:51:24.052Z | 223.428° SW |
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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