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NAVSTAR 18 (USA 50), 20452

Orbit data source: Space-Track

NAVSTAR 18 (USA 50), 20452 is a payload satellite owned by USAF SSD (US) in MEO that was launched on Wed, 24 Jan 1990 UTC via a DELTA 6925 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/20452?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/20452?theme=dark&initialShowStats=false

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ISO8601 Format

Identifier

20452, 1990-008A

Orbit

MEO

Country

Related business

United States Air Force (US)

Manufacturer

Rockwell/SB

Mission

Non-operational Defense Navigation

Bus & Motor

GPS II, STAR 37F

Mass

1,667 kg wet, 776 kg dry

Launch date (UTC)

1990-01-24 (36 years ago)

Launch vehicle

DELTA 6925

Launch site

Air Force Eastern Test Range (AFETR)

Object type

Payload

Rocket body

Debris

Shape & HBR

Box + 2 Pan, 2.6 m

Radar Cross Section

7.641 m², Large (>1 m²)

Expand to show TLE details & history
Last TLE update: 2 days ago

TLE from 2 days ago

0 NAVSTAR 18 (USA 50)
1 20452U 90008A   26183.05211297  .00000029  00000-0  00000-0 0  9998
2 20452  54.8660 133.1285 0015677 283.4285  79.7666  1.89597865256715

Epoch: 2026-07-02T01:15Z

TLE epoch observation values (Epoch: 2026-07-02T01:15:02.560Z)

Latitude

2.79386°

Longitude

-163.77684°

Altitude

21,189.056 km

Speed

3.803 km/s

True Right ascension

09h 00m 20s

True Declination

2° 47' 22"

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

08:34:56

Azimuth

Unknown

Elevation

Unknown

Doppler factor

Unknown

Orbital elements

Apogee altitude

21,239.936 km

Perigee altitude

21,153.478 km

Semi-major axis

27,574.844 km

Eccentricity

0.00157

Inclination

54.866°

RAAN

133.1285°

Arg. of periapsis

283.4285°

True anomaly

79.94345°

Mean anomaly

79.7666°

Eccentric anomaly

79.85502°

Mean motion

0.47399 °/min

Orbital period

759.5 mins

BSTAR

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Other satellites on launch #8 in the year 1990 (1990-01-24 UTC)

DELTA 2 R/B(1), 20453

DELTA 2 R/B(2) (PAM-D), 20450 (Decayed)

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NAVSTAR 18 (USA 50) 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.
337 mins	2026-07-04 05:35:51.713Z	303.694° NW	2026-07-04 08:30:51.713Z	262.426° W	42.615°	2026-07-04 11:12:51.713Z	192.851° SSW
148 mins	2026-07-04 16:58:51.713Z	92.558° ESE	2026-07-04 18:13:51.713Z	62.785° ENE	18.743°	2026-07-04 19:26:51.713Z	37.102° NE

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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 NAVSTAR 18 (USA 50), 20452 on other resources

View NAVSTAR 18 (USA 50), 20452 on NASA - NSSDCA Website

View NAVSTAR 18 (USA 50), 20452 on Heavens-Above

View NAVSTAR 18 (USA 50), 20452 on Keep Track

View NAVSTAR 18 (USA 50), 20452 on Celestrak

View NAVSTAR 18 (USA 50), 20452 on Gunter's Space Page

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

NAVSTAR 18 (USA 50), 20452

Orbit data source: Space-Track

Expand to show TLE details & historyLast TLE update: 2 days ago

TLE from 2 days ago

TLE epoch observation values (Epoch: 2026-07-02T01:15:02.560Z)

Visualization orbit readout

Visualization observer readout

Orbital elements

Other satellites on launch #8 in the year 1990 (1990-01-24 UTC)

NAVSTAR 18 (USA 50) Visibility forecast

Co-orbital & Co-planar RSOs

Check out NAVSTAR 18 (USA 50), 20452 on other resources

Documentation

Expand to show TLE details & history
Last TLE update: 2 days ago