USA 74, 21799
Orbit data source: Space-Track
USA 74, 21799 is an American payload satellite in LEO that was launched on Fri, 08 Nov 1991 UTC via a TITAN 403A launch vehicle from the Air Force Western Test Range (AFWTR). 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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21799 intel report (Beta)
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Identifier
Orbit
Country
USRelated business
Manufacturer
NRL
Mission
Defense Sigint
Bus & Motor
NOSS B SSU, Unknown motor
Mass
~400 kg wet, ~400 kg dry
Launch date (UTC)
Launch vehicle
Launch site
Object type
Shape & HBR
Cyl, 0.5 m
Radar Cross Section
1.178 m², Large (>1 m²)
Expand to show TLE details & historyLast TLE update: 7 hours ago
TLE from 7 hours ago
0 USA 74
1 21799U 91076C 26150.11437672 .00006996 00000-0 51391-3 0 9998
2 21799 63.2936 192.4643 0882790 72.8739 296.6965 13.61377768101147Epoch: 2026-05-30T02:44Z
TLE epoch observation values (Epoch: 2026-05-30T02:44:42.148Z)
Latitude
-0.00001°
Longitude
-96.34637°
Altitude
787.352 km
Speed
7.583 km/s
True Right ascension
12h 49m 51s
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
18:52:23
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
1,683.448 km
Perigee altitude
375.569 km
Semi-major axis
7,407.646 km
Eccentricity
0.08828
Inclination
63.2936°
RAAN
192.4643°
Arg. of periapsis
72.8739°
True anomaly
287.23196°
Mean anomaly
296.6965°
Eccentric anomaly
292.00702°
Mean motion
3.40426 °/min
Orbital period
105.75 mins
BSTAR
0.00051391
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Other satellites on launch #76 in the year 1991 (1991-11-08 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.USA 74 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 | 2026-05-30 12:03:14.530Z | 17.731° NNE | 2026-05-30 12:05:14.530Z | 51.119° ENE | 14.899° | 2026-05-30 12:07:14.530Z | 78.842° E |
| 8 mins | 2026-05-30 13:51:14.530Z | 311.783° NW | 2026-05-30 13:54:14.530Z | 222.906° SW | 40.558° | 2026-05-30 13:59:14.530Z | 160.245° S |
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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