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: 20 hours ago
TLE from 20 hours ago
0 OV1-4
1 02121U 66025A 25302.53231887 .00000350 00000-0 67838-4 0 9998
2 02121 144.5060 284.2508 0082971 159.5357 200.8663 13.87286124 19095Epoch: 2025-10-29T12:46Z
TLE epoch observation values (Epoch: 2025-10-29T12:46:32.350Z)
Latitude
-0°
Longitude
54.51191°
Altitude
993.952 km
Speed
7.328 km/s
True Right ascension
18h 57m 00s
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
04:42:01
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
1,001.867 km
Perigee altitude
880.41 km
Semi-major axis
7,319.275 km
Eccentricity
0.0083
Inclination
144.506°
RAAN
284.2508°
Arg. of periapsis
159.5357°
True anomaly
200.5309°
Mean anomaly
200.8663°
Eccentric anomaly
200.69828°
Mean motion
3.4661 °/min
Orbital period
103.86 mins
BSTAR
0.000067838
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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. |
|---|---|---|---|---|---|---|---|
| 4 mins | 2025-10-30 13:34:44.549Z | 126.661° SE | 2025-10-30 13:36:44.549Z | 149.805° SSE | 13.04° | 2025-10-30 13:38:44.549Z | 172.835° S |
| 8 mins | 2025-10-30 15:11:44.549Z | 104.589° ESE | 2025-10-30 15:15:44.549Z | 168.514° S | 28.691° | 2025-10-30 15:19:44.549Z | 221.217° SW |
| 9 mins | 2025-10-30 16:49:44.549Z | 100.522° ESE | 2025-10-30 16:53:44.549Z | 170.768° S | 39.147° | 2025-10-30 16:58:44.549Z | 249.095° W |
| 9 mins | 2025-10-30 18:27:44.549Z | 112.531° SE | 2025-10-30 18:31:44.549Z | 172.129° S | 39.188° | 2025-10-30 18:36:44.549Z | 261.668° W |
| 8 mins | 2025-10-30 20:06:44.549Z | 142.767° SSE | 2025-10-30 20:10:44.549Z | 206.063° SW | 30.23° | 2025-10-30 20:14:44.549Z | 259.929° W |
| 5 mins | 2025-10-30 21:46:44.549Z | 184.581° SSW | 2025-10-30 21:48:44.549Z | 207.094° SW | 15.194° | 2025-10-30 21:51:44.549Z | 240.629° WSW |
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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