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: 1 day ago
TLE from 1 day ago
0 USA 74
1 21799U 91076C 25255.70780054 .00007943 00000-0 63794-3 0 9996
2 21799 63.2977 168.6266 0889963 67.8774 301.4253 13.57516684 65871Epoch: 2025-09-12T16:59Z
TLE epoch observation values (Epoch: 2025-09-12T16:59:13.966Z)
Latitude
-0.00005°
Longitude
-78.13326°
Altitude
747.82 km
Speed
7.63 km/s
True Right ascension
11h 14m 30s
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
09:35:19
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
1,704.055 km
Perigee altitude
383.049 km
Semi-major axis
7,421.689 km
Eccentricity
0.089
Inclination
63.2977°
RAAN
168.6266°
Arg. of periapsis
67.8774°
True anomaly
292.22846°
Mean anomaly
301.4253°
Eccentric anomaly
296.877°
Mean motion
3.3946 °/min
Orbital period
106.05 mins
BSTAR
0.00063794
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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. |
|---|---|---|---|---|---|---|---|
| 5 mins | 2025-09-13 19:39:02.518Z | 183.01° SSW | 2025-09-13 19:41:02.518Z | 139.541° SSE | 30.244° | 2025-09-13 19:44:02.518Z | 53.588° ENE |
| 9 mins | 2025-09-14 04:52:02.518Z | 320.324° NNW | 2025-09-14 04:55:02.518Z | 243.929° WSW | 44.18° | 2025-09-14 05:01:02.518Z | 152.9° SSE |
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 ascending order |
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CAUTION: Conjunctions in this section are generated from low-fidelity TLE screenings
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