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.
Focus sentinelFocus sentinel
Request partner network tasking
Focus sentinelFocus sentinel
Embed this page
Focus sentinelFocus sentinel
66121 intel report (Beta)
Focus sentinelFocus sentinel
Edit Public Description
Focus sentinelFocus sentinel
Create New Watchlist
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: 17 hours ago
TLE from 17 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
06:57:27
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
Loading maneuver chart data...
Computing Atmospheric mass density...
Loading historical data...
Loading historical data...
Loading historical data...
Loading historical data...
Loading historical data...
Loading historical data...
Loading historical data...
Other satellites on launch #237 in the year 2025 (2025-10-22 UTC)
Did you know?
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
Loading observer location...
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 | 2026-03-03 03:20:14.964Z | 221.998° SW | 2026-03-03 03:23:14.964Z | 160.173° S | 43.717° | 2026-03-03 03:26:14.964Z | 54.394° ENE |
| 4 mins | 2026-03-03 05:00:14.964Z | 306.258° NW | 2026-03-03 05:01:14.964Z | 327.258° NNW | 18.814° | 2026-03-03 05:04:14.964Z | 23.982° NE |
| 5 mins | 2026-03-03 09:56:14.964Z | 321.934° NNW | 2026-03-03 09:58:14.964Z | 21.657° NNE | 41.053° | 2026-03-03 10:01:14.964Z | 116.469° SE |
| 6 mins | 2026-03-04 02:51:14.964Z | 214.349° SW | 2026-03-04 02:54:14.964Z | 100.743° ESE | 39.975° | 2026-03-04 02:57:14.964Z | 56.447° ENE |
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 |
|---|
CAUTION: Conjunctions in this section are generated from low-fidelity TLE screenings
Authenticating...
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 descending order |
|---|