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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Edit Public Description
Identifier
Orbit
Country
USRelated business
Manufacturer
SpaceX/Seattle
Mission
Operational spacecraft
Bus & Motor
STARLINK V2MO, Unknown motor
Mass
575 kg wet, ~530 kg dry
Launch date (UTC)
Launch vehicle
Launch site
Object type
Shape & HBR
Unknown shape, 17.7 m
Radar Cross Section
RCS unknown
Expand to show TLE details & historyLast TLE update: 16 hours ago
TLE from 16 hours ago
0 STARLINK-35631
1 66121U 25237H 25311.25001157 -.01986513 00000-0 -15365-1 0 9994
2 66121 53.1600 255.9571 0000893 83.4671 51.1018 15.74146575 3774Epoch: 2025-11-07T06:00Z
TLE epoch observation values (Epoch: 2025-11-07T06:00:00.999Z)
Latitude
34.86976°
Longitude
-92.01674°
Altitude
349.236 km
Speed
7.704 km/s
True Right ascension
02h 58m 44s
True Declination
34° 41' 56"
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
17:46:14
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
347.923 km
Perigee altitude
346.721 km
Semi-major axis
6,725.459 km
Eccentricity
0.00009
Inclination
53.16°
RAAN
255.9571°
Arg. of periapsis
83.4671°
True anomaly
51.10976°
Mean anomaly
51.1018°
Eccentric anomaly
51.10578°
Mean motion
3.93514 °/min
Orbital period
91.48 mins
BSTAR
-0.015365
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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. |
|---|---|---|---|---|---|---|---|
| 4 mins | 2025-11-07 22:22:22.050Z | 176.533° S | 2025-11-07 22:24:22.050Z | 124.685° SE | 19.764° | 2025-11-07 22:26:22.050Z | 80.202° E |
| 4 mins | 2025-11-08 06:22:22.050Z | 283.194° WNW | 2025-11-08 06:23:22.050Z | 248.401° W | 33.035° | 2025-11-08 06:26:22.050Z | 152.262° SSE |
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 ascending order |
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CAUTION: Conjunctions in this section are generated from low-fidelity TLE screenings
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Click to sort rows by Secondary header in ascending order | Click to sort rows by Secondary name header in ascending order | Click to sort rows by Country header in ascending order | Click to sort rows by Owner header in ascending order | Click to sort rows by Obj. Type header in ascending order | Click to sort rows by Miss dist. header in ascending order | Click to sort rows by Rel. speed header in ascending order | Click to sort rows by Apr. angle header in ascending order | Click to sort rows by TCA header in ascending order |
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