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
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: 23 hours ago
TLE from 23 hours ago
0 VANGUARD 3
1 00020U 59007A 26007.00230869 .00001925 00000-0 74985-3 0 9999
2 00020 33.3536 127.2219 1640025 269.5284 71.8028 11.61710393465862Epoch: 2026-01-07T00:03Z
TLE epoch observation values (Epoch: 2026-01-07T00:03:19.470Z)
Latitude
0.00002°
Longitude
19.81379°
Altitude
1,646.64 km
Speed
7.139 km/s
True Right ascension
08h 28m 53s
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
23:15:31
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
3,211.114 km
Perigee altitude
508.953 km
Semi-major axis
8,238.171 km
Eccentricity
0.164
Inclination
33.3536°
RAAN
127.2219°
Arg. of periapsis
269.5284°
True anomaly
90.53205°
Mean anomaly
71.8028°
Eccentric anomaly
81.08596°
Mean motion
2.90267 °/min
Orbital period
124.02 mins
BSTAR
0.00074985
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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. |
|---|---|---|---|---|---|---|---|
| 21 mins | 2026-01-08 09:10:54.415Z | 182.924° SSW | 2026-01-08 09:19:54.415Z | 133.84° SE | 24.384° | 2026-01-08 09:31:54.415Z | 89.083° E |
| 30 mins | 2026-01-08 11:19:54.415Z | 226.544° WSW | 2026-01-08 11:31:54.415Z | 158.621° S | 39.804° | 2026-01-08 11:49:54.415Z | 86.632° E |
| 34 mins | 2026-01-08 13:31:54.415Z | 256.161° W | 2026-01-08 13:47:54.415Z | 170.359° S | 43.329° | 2026-01-08 14:05:54.415Z | 100.479° ESE |
| 33 mins | 2026-01-08 15:45:54.415Z | 271.779° WNW | 2026-01-08 16:02:54.415Z | 203.726° SW | 40.894° | 2026-01-08 16:18:54.415Z | 126.907° SE |
| 25 mins | 2026-01-08 18:02:54.415Z | 271.661° WNW | 2026-01-08 18:16:54.415Z | 220.388° SW | 28.31° | 2026-01-08 18:27:54.415Z | 167.436° S |
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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