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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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<iframe src="https://www.satcat.com/sats-embedded/20?theme=dark&initialShowStats=false" width="600" height="400" frameborder="0" title="Kayhan Space Satcat Satellite Viewer"></iframe>

Iframe URL

https://www.satcat.com/sats-embedded/20?theme=dark&initialShowStats=false

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ISO8601 Format

Identifier

20, 1959-007A

Orbit

LEO

Country

Related business

National Aeronautics and Space Administration (NASA) (US)

Manufacturer

NRL

Mission

Spacecraft

Bus & Motor

NRL 20", Unknown motor

Mass

47 kg wet, 23 kg dry

Launch date (UTC)

1959-09-18 (67 years ago)

Launch vehicle

VANGUARD

Launch site

Air Force Eastern Test Range (AFETR)

Object type

Payload

Rocket body

Debris

Shape & HBR

Unknown

Radar Cross Section

Medium (>0.1 m² and <1 m²)

Expand to show TLE details & history
Last TLE update: 14 hours ago

TLE from 14 hours ago

0 VANGUARD 3
1 00020U 59007A   26104.06033964  .00000355  00000-0  15032-3 0  9994
2 00020  33.3387 137.8219 1637323  69.7937 307.0809 11.61922188477158

Epoch: 2026-04-14T01:26Z

TLE epoch observation values (Epoch: 2026-04-14T01:26:53.344Z)

Latitude

-0.00005°

Longitude

-86.14245°

Altitude

1,204.101 km

Speed

7.534 km/s

True Right ascension

09h 11m 17s

True Declination

0° 00' 00"

Sunlit

Object was in daylight at epoch

Visualization orbit readout

Latitude

Unknown

Longitude

Unknown

Altitude

Unknown

Speed

Unknown

Apparent Right ascension

Unknown

Apparent Declination

Unknown

Sunlit

N/A

Visualization observer readout

Local Sidereal Time

21:44:24

Azimuth

Unknown

Elevation

Unknown

Doppler factor

Unknown

Orbital elements

Apogee altitude

3,207.726 km

Perigee altitude

510.344 km

Semi-major axis

8,237.172 km

Eccentricity

0.16373

Inclination

33.3387°

RAAN

137.8219°

Arg. of periapsis

69.7937°

True anomaly

290.26725°

Mean anomaly

307.0809°

Eccentric anomaly

298.86527°

Mean motion

2.90319 °/min

Orbital period

124 mins

BSTAR

0.00015032

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Other satellites on launch #7 in the year 1959 (1959-09-18 UTC)

VANGUARD 3 DEB, 29005 (Decayed)

VANGUARD 3 DEB, 31405 (Decayed)

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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.

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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.
4 mins	2026-04-15 06:36:39.302Z	208.486° SW	2026-04-15 06:38:39.302Z	168.491° S	20.491°	2026-04-15 06:40:39.302Z	125.776° SE
6 mins	2026-04-15 08:46:39.302Z	234.583° WSW	2026-04-15 08:48:39.302Z	187.171° SSW	27.978°	2026-04-15 08:52:39.302Z	118.731° SE
6 mins	2026-04-15 10:57:39.302Z	221.529° SW	2026-04-15 10:59:39.302Z	188.88° SSW	20.567°	2026-04-15 11:03:39.302Z	148.38° SSE

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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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Check out VANGUARD 3, 20 on other resources

View VANGUARD 3, 20 on NASA - NSSDCA Website

View VANGUARD 3, 20 on Heavens-Above

View VANGUARD 3, 20 on Keep Track

View VANGUARD 3, 20 on Celestrak

View VANGUARD 3, 20 on Gunter's Space Page

Satcat and Kayhan Space are not affiliated with NASA, Celestrak, Heavens-Above, Keep Track, or Gunter's Space Page.

VANGUARD 3, 20

Orbit data source: Space-Track

Expand to show TLE details & historyLast TLE update: 14 hours ago

TLE from 14 hours ago

TLE epoch observation values (Epoch: 2026-04-14T01:26:53.344Z)

Visualization orbit readout

Visualization observer readout

Orbital elements

Other satellites on launch #7 in the year 1959 (1959-09-18 UTC)

VANGUARD 3 Visibility forecast

Co-orbital & Co-planar RSOs

Check out VANGUARD 3, 20 on other resources

Documentation

Expand to show TLE details & history
Last TLE update: 14 hours ago