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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Edit Public Description
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: 18 hours ago
TLE from 18 hours ago
0 USA 74
1 21799U 91076C 25319.83713801 .00006415 00000-0 50365-3 0 9990
2 21799 63.2993 356.9429 0887799 69.1180 300.2540 13.58705836 74587Epoch: 2025-11-15T20:05Z
TLE epoch observation values (Epoch: 2025-11-15T20:05:28.724Z)
Latitude
0.00001°
Longitude
0.41267°
Altitude
756.839 km
Speed
7.619 km/s
True Right ascension
23h 47m 46s
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
11:11:13
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
1,697.732 km
Perigee altitude
380.707 km
Semi-major axis
7,417.356 km
Eccentricity
0.08878
Inclination
63.2993°
RAAN
356.9429°
Arg. of periapsis
69.118°
True anomaly
290.98789°
Mean anomaly
300.254°
Eccentric anomaly
295.6693°
Mean motion
3.39758 °/min
Orbital period
105.96 mins
BSTAR
0.00050365
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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. |
|---|---|---|---|---|---|---|---|
| 6 mins | 2025-11-17 04:01:02.298Z | 194.145° SSW | 2025-11-17 04:04:02.298Z | 143.242° SSE | 33.838° | 2025-11-17 04:07:02.298Z | 49.697° ENE |
| 4 mins | 2025-11-17 11:27:02.298Z | 26.136° NE | 2025-11-17 11:28:02.298Z | 42.169° NE | 14.342° | 2025-11-17 11:31:02.298Z | 81.304° E |
| 8 mins | 2025-11-17 13:15:02.298Z | 314.688° NW | 2025-11-17 13:18:02.298Z | 201.333° SSW | 41.993° | 2025-11-17 13:23:02.298Z | 156.399° SSE |
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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