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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.

Not visible in the next 10 days

Iframe embed code

<iframe src="https://www.satcat.com/sats-embedded/41937?theme=dark&initialShowStats=false" width="600" height="400" frameborder="0" title="Kayhan Space Satcat Satellite Viewer"></iframe>

Iframe URL

https://www.satcat.com/sats-embedded/41937?theme=dark&initialShowStats=false

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ISO8601 Format

Identifier

41937, 2017-004A

Orbit

GEO

Country

Related business

United States Air Force (US)

Manufacturer

LMSS

Mission

Operational Defense Early Warn

Bus & Motor

A2100, LEROS 1C?

Mass

~4,500 kg wet, ~2,500 kg dry

Launch date (UTC)

2017-01-21 (9 years ago)

Launch vehicle

ATLAS V 401

Launch site

Air Force Eastern Test Range (AFETR)

Object type

Payload

Rocket body

Debris

Shape & HBR

Box + 2 Pan, 12.5 m

Radar Cross Section

33.213 m², Large (>1 m²)

Expand to show TLE details & history
Last TLE update: 11 hours ago

TLE from 11 hours ago

0 SBIRS GEO 4 (USA 273)
1 41937U 17004A   25259.23103968  .00000106  00000-0  00000-0 0  9998
2 41937   1.7661  32.7150 0001839 148.6326 278.1306  1.00269955 31857

Epoch: 2025-09-16T05:32Z

TLE epoch observation values (Epoch: 2025-09-16T05:32:41.828Z)

Latitude

1.6076°

Longitude

20.847°

Altitude

35,785.292 km

Speed

3.075 km/s

True Right ascension

06h 37m 46s

True Declination

1° 36' 22"

Sunlit

Object was in daylight at epoch

Visualization orbit readout

Latitude

Unknown

Longitude

Unknown

Altitude

Unknown

Speed

Unknown

Apparent Right ascension

Unknown

Apparent Declination

Unknown

Sunlit

N/A

Visualization observer readout

Local Sidereal Time

09:29:22

Azimuth

Unknown

Elevation

Unknown

Doppler factor

Unknown

Orbital elements

Apogee altitude

35,795.931 km

Perigee altitude

35,780.422 km

Semi-major axis

42,166.314 km

Eccentricity

0.00018

Inclination

1.7661°

RAAN

32.715°

Arg. of periapsis

148.6326°

True anomaly

278.10974°

Mean anomaly

278.1306°

Eccentric anomaly

278.12017°

Mean motion

0.25067 °/min

Orbital period

1,436.18 mins

BSTAR

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Other satellites on launch #4 in the year 2017 (2017-01-21 UTC)

ATLAS 5 CENTAUR R/B, 41938 (Decayed)

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SBIRS GEO 4 (USA 273) Visibility

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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

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CAUTION: Conjunctions in this section are generated from low-fidelity TLE screenings

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Check out SBIRS GEO 4 (USA 273), 41937 on other resources

View SBIRS GEO 4 (USA 273), 41937 on NASA - NSSDCA Website

View SBIRS GEO 4 (USA 273), 41937 on Heavens-Above

View SBIRS GEO 4 (USA 273), 41937 on Keep Track

View SBIRS GEO 4 (USA 273), 41937 on Celestrak

View SBIRS GEO 4 (USA 273), 41937 on Gunter's Space Page

Satcat and Kayhan Space are not affiliated with NASA, Celestrak, Heavens-Above, Keep Track, or Gunter's Space Page.

SBIRS GEO 4 (USA 273), 41937

Orbit data source: Space-Track

Expand to show TLE details & historyLast TLE update: 11 hours ago

TLE from 11 hours ago

TLE epoch observation values (Epoch: 2025-09-16T05:32:41.828Z)

Visualization orbit readout

Visualization observer readout

Orbital elements

Other satellites on launch #4 in the year 2017 (2017-01-21 UTC)

SBIRS GEO 4 (USA 273) Visibility

41937 neighbors

Co-orbital & Co-planar RSOs

Check out SBIRS GEO 4 (USA 273), 41937 on other resources

Documentation

Expand to show TLE details & history
Last TLE update: 11 hours ago