DMSP 5D-2 F11 (USA 73), 21798
Orbit data source: Space-Track
DMSP 5D-2 F11 (USA 73), 21798 is a payload satellite owned by USAF SSD (US) in SSO that was launched on Thu, 28 Nov 1991 UTC via an ATLAS E 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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21798 intel report (Beta)
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Edit Public Description
Identifier
Orbit
Country
USRelated business
Manufacturer
GE/East Windsor
Mission
Non-operational Defense Weather
Bus & Motor
BLOCK 5D, STAR 37S
Mass
1,456 kg wet, 749 kg dry
Launch date (UTC)
Launch vehicle
Launch site
Object type
Shape & HBR
Cyl + 1 Pan, 2.5 m
Radar Cross Section
4.290 m², Large (>1 m²)
Expand to show TLE details & historyLast TLE update: 11 hours ago
TLE from 11 hours ago
0 DMSP 5D-2 F11 (USA 73)
1 21798U 91082A 25349.95317521 .00000108 00000-0 74517-4 0 9990
2 21798 98.7113 17.0329 0013741 78.7519 281.5200 14.17386989759176Epoch: 2025-12-15T22:52Z
TLE epoch observation values (Epoch: 2025-12-15T22:52:34.338Z)
Latitude
0.00004°
Longitude
-50.95453°
Altitude
835.148 km
Speed
7.436 km/s
True Right ascension
01h 08m 07s
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
08:40:39
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
841.272 km
Perigee altitude
821.459 km
Semi-major axis
7,209.503 km
Eccentricity
0.00137
Inclination
98.7113°
RAAN
17.0329°
Arg. of periapsis
78.7519°
True anomaly
281.36566°
Mean anomaly
281.52°
Eccentric anomaly
281.44283°
Mean motion
3.54556 °/min
Orbital period
101.54 mins
BSTAR
0.000074517
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Other satellites on launch #82 in the year 1991 (1991-11-28 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.DMSP 5D-2 F11 (USA 73) 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. |
|---|---|---|---|---|---|---|---|
| 10 mins | 2025-12-16 14:41:55.414Z | 18.546° NNE | 2025-12-16 14:46:55.414Z | 107.159° ESE | 43.445° | 2025-12-16 14:51:55.414Z | 186.494° SSW |
| 4 mins | 2025-12-16 16:24:55.414Z | 320.288° NNW | 2025-12-16 16:26:55.414Z | 295.159° NW | 14.955° | 2025-12-16 16:28:55.414Z | 271.356° WNW |
| 4 mins | 2025-12-17 00:28:55.414Z | 80.545° E | 2025-12-17 00:30:55.414Z | 55.58° ENE | 14.492° | 2025-12-17 00:32:55.414Z | 32.241° NE |
| 9 mins | 2025-12-17 02:05:55.414Z | 173.7° S | 2025-12-17 02:09:55.414Z | 225.878° WSW | 43.315° | 2025-12-17 02:14:55.414Z | 341.56° N |
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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