STARLINK-35631, 66121
Orbit data source: Space-Track
STARLINK-35631, 66121 is a payload satellite owned by SpaceX/Seattle (US) in LEO that was launched on Wed, 22 Oct 2025 UTC via an FALCON 9 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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66121 intel report (Beta)
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Identifier
Orbit
Country
USRelated business
Manufacturer
SpaceX/Seattle
Mission
Operational Commercial Communications
Bus & Motor
STARLINK V2MO, Unknown motor
Mass
575 kg wet, ~530 kg dry
Launch date (UTC)
Launch vehicle
Launch site
Object type
Shape & HBR
Box + 2 Pan, 17.7 m
Radar Cross Section
36.964 m²
Expand to show TLE details & historyLast TLE update: 16 hours ago
TLE from 16 hours ago
0 STARLINK-35631
1 66121U 25237H 26061.41337747 .00025298 00000-0 86369-3 0 9997
2 66121 53.1600 73.6272 0001430 86.4016 273.7148 15.30187063 21495Epoch: 2026-03-02T09:55Z
TLE epoch observation values (Epoch: 2026-03-02T09:55:15.813Z)
Latitude
-0.00004°
Longitude
124.60414°
Altitude
476.09 km
Speed
7.629 km/s
True Right ascension
04h 54m 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
05:24:47
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
476.49 km
Perigee altitude
474.53 km
Semi-major axis
6,853.647 km
Eccentricity
0.00014
Inclination
53.16°
RAAN
73.6272°
Arg. of periapsis
86.4016°
True anomaly
273.69845°
Mean anomaly
273.7148°
Eccentric anomaly
273.70662°
Mean motion
3.82526 °/min
Orbital period
94.11 mins
BSTAR
0.00086369
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Other satellites on launch #237 in the year 2025 (2025-10-22 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.STARLINK-35631 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. |
|---|---|---|---|---|---|---|---|
| 7 mins | 2026-03-03 03:19:50.403Z | 222.59° SW | 2026-03-03 03:23:50.403Z | 81.076° E | 41.55° | 2026-03-03 03:26:50.403Z | 53.464° ENE |
| 4 mins | 2026-03-03 08:17:50.403Z | 342.823° N | 2026-03-03 08:19:50.403Z | 17.261° NNE | 14.908° | 2026-03-03 08:21:50.403Z | 52.428° ENE |
| 6 mins | 2026-03-03 09:55:50.403Z | 319.539° NNW | 2026-03-03 09:58:50.403Z | 73.94° E | 39.612° | 2026-03-03 10:01:50.403Z | 118.535° SE |
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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