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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Edit Public Description
Identifier
Orbit
Country
USRelated business
Manufacturer
NRL
Mission
Civil Science
Bus & Motor
NRL 20", Unknown motor
Mass
47 kg wet, 23 kg dry
Launch date (UTC)
Launch vehicle
Launch site
Object type
Shape & HBR
Sphere + Cyl, 1.3 m
Radar Cross Section
1.104 m², Medium (>0.1 m² and < 1m²)
Expand to show TLE details & historyLast TLE update: 1 day ago
TLE from 1 day ago
0 VANGUARD 3
1 00020U 59007A 25261.07963572 .00002310 00000-0 94620-3 0 9998
2 00020 33.3388 166.2417 1639797 35.3782 334.5283 11.61015826452964Epoch: 2025-09-18T01:54Z
TLE epoch observation values (Epoch: 2025-09-18T01:54:40.526Z)
Latitude
0.00001°
Longitude
140.32648°
Altitude
691.69 km
Speed
8.026 km/s
True Right ascension
11h 04m 58s
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
20:08:53
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
3,214.75 km
Perigee altitude
511.887 km
Semi-major axis
8,241.456 km
Eccentricity
0.16398
Inclination
33.3388°
RAAN
166.2417°
Arg. of periapsis
35.3782°
True anomaly
324.68262°
Mean anomaly
334.5283°
Eccentric anomaly
329.80263°
Mean motion
2.90093 °/min
Orbital period
124.1 mins
BSTAR
0.0009462
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Other satellites on launch #7 in the year 1959 (1959-09-18 UTC)
Did you know?
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. |
|---|---|---|---|---|---|---|---|
| 10 mins | 2025-09-19 03:16:12.283Z | 193.845° SSW | 2025-09-19 03:16:12.283Z | 193.845° SSW | 27.796° | 2025-09-19 03:26:12.283Z | 143.14° SSE |
| 10 mins | 2025-09-19 05:25:12.283Z | 227.965° WSW | 2025-09-19 05:28:12.283Z | 212.379° SW | 14.09° | 2025-09-19 05:35:12.283Z | 183.609° SSW |
| 4 mins | 2025-09-19 21:32:12.283Z | 178.727° S | 2025-09-19 21:33:12.283Z | 157.902° S | 18.997° | 2025-09-19 21:36:12.283Z | 112.115° ESE |
| 8 mins | 2025-09-19 23:41:12.283Z | 230.023° WSW | 2025-09-19 23:43:12.283Z | 184.055° SSW | 34.073° | 2025-09-19 23:49:12.283Z | 108.308° ESE |
| 13 mins | 2025-09-20 01:50:12.283Z | 250.676° W | 2025-09-20 01:54:12.283Z | 199.189° SSW | 31.314° | 2025-09-20 02:03:12.283Z | 130.484° SE |
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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