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, Large (>1 m²)
Expand to show TLE details & historyLast TLE update: 12 hours ago
TLE from 12 hours ago
0 STARLINK-35631
1 66121U 25237H 26171.33814507 .00015230 00000-0 52533-3 0 9995
2 66121 53.1594 283.0357 0001200 95.4040 264.7097 15.30196104 38329Epoch: 2026-06-20T08:06Z
TLE epoch observation values (Epoch: 2026-06-20T08:06:55.734Z)
Latitude
-0.00005°
Longitude
-107.25077°
Altitude
476.202 km
Speed
7.629 km/s
True Right ascension
18h 52m 08s
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
07:23:52
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
476.306 km
Perigee altitude
474.661 km
Semi-major axis
6,853.62 km
Eccentricity
0.00012
Inclination
53.1594°
RAAN
283.0357°
Arg. of periapsis
95.404°
True anomaly
264.69601°
Mean anomaly
264.7097°
Eccentric anomaly
264.70285°
Mean motion
3.82528 °/min
Orbital period
94.11 mins
BSTAR
0.00052533
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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. |
|---|---|---|---|---|---|---|---|
| 6 mins | 2026-06-21 09:21:06.496Z | 193.493° SSW | 2026-06-21 09:24:06.496Z | 128.652° SE | 27.921° | 2026-06-21 09:27:06.496Z | 69.442° E |
| 5 mins | 2026-06-21 11:00:06.496Z | 280.157° WNW | 2026-06-21 11:02:06.496Z | 336.882° NNW | 27.941° | 2026-06-21 11:05:06.496Z | 33.682° NE |
| 5 mins | 2026-06-21 15:57:06.496Z | 343.776° N | 2026-06-21 15:59:06.496Z | 41.362° NE | 27.5° | 2026-06-21 16:02:06.496Z | 95.8° ESE |
| 4 mins | 2026-06-21 17:35:06.496Z | 273.3° WNW | 2026-06-21 17:37:06.496Z | 212.941° SW | 27.717° | 2026-06-21 17:39:06.496Z | 170.513° S |
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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