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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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
DOMED CYL, 1.1 m
Radar Cross Section
Medium (>0.1 m² and <1 m²)
Expand to show TLE details & historyLast TLE update: 19 hours ago
TLE from 19 hours ago
0 OV1-4
1 02121U 66025A 26312.10886920 .00000288 00000-0 16532-4 0 9992
2 02121 144.5058 7.2015 0083803 312.6457 46.7192 13.87341087 71133Epoch: 2026-11-08T02:36Z
TLE epoch observation values (Epoch: 2026-11-08T02:36:46.298Z)
Latitude
-0.00003°
Longitude
-79.29587°
Altitude
895.235 km
Speed
7.428 km/s
True Right ascension
00h 28m 48s
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
17:57:59
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
1,002.281 km
Perigee altitude
879.609 km
Semi-major axis
7,319.082 km
Eccentricity
0.00838
Inclination
144.5058°
RAAN
7.2015°
Arg. of periapsis
312.6457°
True anomaly
47.42335°
Mean anomaly
46.7192°
Eccentric anomaly
47.07077°
Mean motion
3.46624 °/min
Orbital period
103.86 mins
BSTAR
0.000016532
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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. |
|---|---|---|---|---|---|---|---|
| 11 mins | 2026-11-08 21:59:05.741Z | 97.854° ESE | 2026-11-08 22:04:05.741Z | 162.218° S | 58.364° | 2026-11-08 22:10:05.741Z | 255.139° W |
| 10 mins | 2026-11-08 23:38:05.741Z | 116.422° SE | 2026-11-08 23:43:05.741Z | 207.681° SW | 52.024° | 2026-11-08 23:48:05.741Z | 265.577° W |
| 7 mins | 2026-11-09 01:18:05.741Z | 156.431° SSE | 2026-11-09 01:21:05.741Z | 204.014° SW | 31.018° | 2026-11-09 01:25:05.741Z | 257.507° W |
| 6 mins | 2026-11-09 18:56:05.741Z | 117.586° SE | 2026-11-09 18:59:05.741Z | 152.78° SSE | 18.976° | 2026-11-09 19:02:05.741Z | 186.978° SSW |
| 9 mins | 2026-11-09 20:33:05.741Z | 99.16° ESE | 2026-11-09 20:37:05.741Z | 153.678° SSE | 40.059° | 2026-11-09 20:42:05.741Z | 227.293° 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 descending order |
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CAUTION: Conjunctions in this section are generated from low-fidelity TLE screenings
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