SBIRS GEO 4 (USA 273), 41937
Orbit data source: Space-Track
SBIRS GEO 4 (USA 273), 41937 is a payload satellite owned by USAF AFSPC (US) in GEO that was launched on Sat, 21 Jan 2017 UTC via an ATLAS V 401 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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41937 intel report (Beta)
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Identifier
Orbit
Country
USRelated business
Manufacturer
LMSS
Mission
Operational Defense Early Warn
Bus & Motor
A2100, LEROS 1C?
Mass
~4,500 kg wet, ~2,500 kg dry
Launch date (UTC)
Launch vehicle
Launch site
Object type
Shape & HBR
Box + 2 Pan, 12.5 m
Radar Cross Section
33.213 m², Large (>1 m²)
Expand to show TLE details & historyLast TLE update: 2 days ago
TLE from 2 days ago
0 SBIRS GEO 4 (USA 273)
1 41937U 17004A 26171.25353019 .00000118 00000-0 00000+0 0 9990
2 41937 2.2498 43.3808 0002075 36.5270 300.7222 1.00272087 34622Epoch: 2026-06-20T06:05Z
TLE epoch observation values (Epoch: 2026-06-20T06:05:05.008Z)
Latitude
-0.86603°
Longitude
20.89657°
Altitude
35,781.642 km
Speed
3.075 km/s
True Right ascension
01h 22m 33s
True Declination
0° 51' 55"
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
21:39:51
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
35,796.328 km
Perigee altitude
35,778.829 km
Semi-major axis
42,165.715 km
Eccentricity
0.00021
Inclination
2.2498°
RAAN
43.3808°
Arg. of periapsis
36.527°
True anomaly
300.70176°
Mean anomaly
300.7222°
Eccentric anomaly
300.71198°
Mean motion
0.25067 °/min
Orbital period
1,436.15 mins
BSTAR
0
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Other satellites on launch #4 in the year 2017 (2017-01-21 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.SBIRS GEO 4 (USA 273) Visibility
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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. |
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| SBIRS GEO 4 (USA 273) is likely not visible in the next few days. |
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41937 neighbors
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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
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 descending order |
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CAUTION: Conjunctions in this section are generated from low-fidelity TLE screenings
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