VANGUARD 3, 20
Orbit data source: Space-Track
VANGUARD 3, 20 is a payload satellite owned by GSFC (US) in LEO that was launched on Fri, 18 Sep 1959 UTC via a VANGUARD launch vehicle from the Air Force Eastern Test Range (AFETR). 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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20 intel report (Beta)
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Identifier
Orbit
Country
USRelated business
Manufacturer
NRL
Mission
Spacecraft
Bus & Motor
NRL 20", Unknown motor
Mass
47 kg wet, 23 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: 6 days ago
TLE from 6 days ago
0 VANGUARD 3
1 00020U 59007A 26151.84374810 .00000453 00000-0 17447-3 0 9991
2 00020 33.3518 325.7874 1638053 325.9498 24.5816 11.61958470482719Epoch: 2026-05-31T20:14Z
TLE epoch observation values (Epoch: 2026-05-31T20:14:59.835Z)
Latitude
-0.00001°
Longitude
132.69846°
Altitude
677.103 km
Speed
8.039 km/s
True Right ascension
21h 43m 08s
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
09:17:03
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
3,208.126 km
Perigee altitude
509.598 km
Semi-major axis
8,236.999 km
Eccentricity
0.16381
Inclination
33.3518°
RAAN
325.7874°
Arg. of periapsis
325.9498°
True anomaly
34.11104°
Mean anomaly
24.5816°
Eccentric anomaly
29.15372°
Mean motion
2.90328 °/min
Orbital period
124 mins
BSTAR
0.00017447
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Other satellites on launch #7 in the year 1959 (1959-09-18 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.VANGUARD 3 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 | 2026-06-07 13:24:01.561Z | 208.227° SW | 2026-06-07 13:29:01.561Z | 142.652° SSE | 26.118° | 2026-06-07 13:35:01.561Z | 95.877° ESE |
| 17 mins | 2026-06-07 15:34:01.561Z | 244.421° WSW | 2026-06-07 15:39:01.561Z | 182.541° SSW | 40.078° | 2026-06-07 15:51:01.561Z | 99.146° ESE |
| 23 mins | 2026-06-07 17:44:01.561Z | 262.151° W | 2026-06-07 17:52:01.561Z | 191.686° SSW | 39.318° | 2026-06-07 18:07:01.561Z | 121.501° SE |
| 25 mins | 2026-06-07 19:56:01.561Z | 260.939° W | 2026-06-07 20:06:01.561Z | 205.224° SW | 29.758° | 2026-06-07 20:21:01.561Z | 151.874° SSE |
| 12 mins | 2026-06-07 22:14:01.561Z | 239.747° WSW | 2026-06-07 22:19:01.561Z | 222.309° SW | 13.16° | 2026-06-07 22:26:01.561Z | 199.967° SSW |
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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