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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)

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Last TLE update: 3 hours ago

TLE from 3 hours ago

0 SBIRS GEO 4 (USA 273)
1 41937U 17004A   25299.83504505  .00000136  00000-0  00000+0 0  9992
2 41937   1.8288  34.6966 0001802 178.1971 144.1053  1.00272785 32254

Epoch: 2025-10-26T20:02Z

TLE epoch observation values (Epoch: 2025-10-26T20:02:27.892Z)

Latitude

-1.10149°

Longitude

20.92863°

Altitude

35,792.133 km

Speed

3.074 km/s

True Right ascension

23h 47m 57s

True Declination

-1° 06' 01"

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

18:51:15

Azimuth

Unknown

Elevation

Unknown

Doppler factor

Unknown

Orbital elements

Apogee altitude

35,794.982 km

Perigee altitude

35,779.785 km

Semi-major axis

42,165.52 km

Eccentricity

0.00018

Inclination

1.8288°

RAAN

34.6966°

Arg. of periapsis

178.1971°

True anomaly

144.1174°

Mean anomaly

144.1053°

Eccentric anomaly

144.11135°

Mean motion

0.25067 °/min

Orbital period

1,436.14 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: 3 hours ago

TLE from 3 hours ago

TLE epoch observation values (Epoch: 2025-10-26T20:02:27.892Z)

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: 3 hours ago