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: 9 hours ago
TLE from 9 hours ago
0 VANGUARD 3
1 00020U 59007A 26203.49783279 .00000242 00000-0 80840-4 0 9997
2 00020 33.3512 139.7725 1638271 242.9368 99.4921 11.61989882488723Epoch: 2026-07-22T11:56Z
TLE epoch observation values (Epoch: 2026-07-22T11:56:52.753Z)
Latitude
-0.00004°
Longitude
20.30031°
Altitude
2,280.173 km
Speed
6.61 km/s
True Right ascension
09h 19m 05s
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
09:36:19
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
3,208.133 km
Perigee altitude
509.294 km
Semi-major axis
8,236.851 km
Eccentricity
0.16383
Inclination
33.3512°
RAAN
139.7725°
Arg. of periapsis
242.9368°
True anomaly
117.12185°
Mean anomaly
99.4921°
Eccentric anomaly
108.39888°
Mean motion
2.90336 °/min
Orbital period
123.99 mins
BSTAR
0.00008084
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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. |
|---|---|---|---|---|---|---|---|
| 31 mins | 2026-07-22 22:23:21.890Z | 211.634° SW | 2026-07-22 22:37:21.890Z | 150.474° SSE | 35.545° | 2026-07-22 22:54:21.890Z | 85.624° E |
| 34 mins | 2026-07-23 00:35:21.890Z | 244.793° WSW | 2026-07-23 00:52:21.890Z | 173.753° S | 42.637° | 2026-07-23 01:09:21.890Z | 92.529° ESE |
| 31 mins | 2026-07-23 02:50:21.890Z | 266.421° W | 2026-07-23 03:08:21.890Z | 189.851° SSW | 42.618° | 2026-07-23 03:21:21.890Z | 113.884° SE |
| 24 mins | 2026-07-23 05:07:21.890Z | 273.728° WNW | 2026-07-23 05:21:21.890Z | 217.346° SW | 33.907° | 2026-07-23 05:31:21.890Z | 150.426° SSE |
| 6 mins | 2026-07-23 07:29:21.890Z | 247.16° WSW | 2026-07-23 07:32:21.890Z | 232.858° WSW | 12.148° | 2026-07-23 07:35:21.890Z | 216.506° SW |
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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