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: 9 hours ago
TLE from 9 hours ago
0 OV1-4
1 02121U 66025A 26290.87571928 .00000347 00000-0 65130-4 0 9994
2 02121 144.5062 260.4548 0083081 161.8471 198.5189 13.87338793 68183Epoch: 2026-10-17T21:01Z
TLE epoch observation values (Epoch: 2026-10-17T21:01:02.145Z)
Latitude
-0.00002°
Longitude
-81.1802°
Altitude
994.667 km
Speed
7.327 km/s
True Right ascension
17h 21m 49s
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
00:59:22
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
1,001.761 km
Perigee altitude
880.146 km
Semi-major axis
7,319.09 km
Eccentricity
0.00831
Inclination
144.5062°
RAAN
260.4548°
Arg. of periapsis
161.8471°
True anomaly
198.21947°
Mean anomaly
198.5189°
Eccentric anomaly
198.36889°
Mean motion
3.46623 °/min
Orbital period
103.86 mins
BSTAR
0.00006513
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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. |
|---|---|---|---|---|---|---|---|
| 7 mins | 2026-10-18 13:07:49.712Z | 109.125° ESE | 2026-10-18 13:11:49.712Z | 157.375° SSE | 18.686° | 2026-10-18 13:14:49.712Z | 193.07° SSW |
| 8 mins | 2026-10-18 14:46:49.712Z | 105.693° ESE | 2026-10-18 14:49:49.712Z | 157.304° SSE | 40.688° | 2026-10-18 14:54:49.712Z | 231.89° WSW |
| 8 mins | 2026-10-18 16:24:49.712Z | 104.555° ESE | 2026-10-18 16:28:49.712Z | 196.007° SSW | 56.67° | 2026-10-18 16:32:49.712Z | 252.993° W |
| 9 mins | 2026-10-18 18:02:49.712Z | 121.179° SE | 2026-10-18 18:06:49.712Z | 195.203° SSW | 51.333° | 2026-10-18 18:11:49.712Z | 264.957° W |
| 8 mins | 2026-10-18 19:41:49.712Z | 155.225° SSE | 2026-10-18 19:44:49.712Z | 197.584° SSW | 29.558° | 2026-10-18 19:49:49.712Z | 261.019° W |
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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