HTV-X1, 66174
Orbit data source: Space-Track
HTV-X1, 66174 is a payload satellite owned by JAXA (JP) in LEO that was launched on Sun, 26 Oct 2025 UTC via a H3-24W launch vehicle from the Tanegashima Space Center (TNSTA). 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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66174 intel report (Beta)
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Edit Public Description
Identifier
Orbit
Country
JP / JPNRelated business
Manufacturer
MHITO?
Mission
Operational spacecraft
Bus & Motor
HTV-X, HBT-5 X 4
Mass
16,000 kg wet, 7,600 kg dry
Launch date (UTC)
Launch vehicle
Launch site
Object type
Shape & HBR
Unknown
Radar Cross Section
RCS unknown
Expand to show TLE details & historyLast TLE update: 16 hours ago
TLE from 16 hours ago
0 HTV-X1
1 66174U 25241A 25304.16626396 .00017194 00000-0 31236-3 0 9991
2 66174 51.6343 353.2496 0004911 359.9780 0.1208 15.49645314 773Epoch: 2025-10-31T03:59Z
TLE epoch observation values (Epoch: 2025-10-31T03:59:25.206Z)
Latitude
0.00002°
Longitude
-106.32001°
Altitude
415.166 km
Speed
7.665 km/s
True Right ascension
23h 32m 59s
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
15:44:22
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
421.609 km
Perigee altitude
414.934 km
Semi-major axis
6,796.409 km
Eccentricity
0.00049
Inclination
51.6343°
RAAN
353.2496°
Arg. of periapsis
359.978°
True anomaly
0.12092°
Mean anomaly
0.1208°
Eccentric anomaly
0.12086°
Mean motion
3.87368 °/min
Orbital period
92.93 mins
BSTAR
0.00031236
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Other satellites on launch #241 in the year 2025 (2025-10-26 UTC)
No other RSOs were in this launch
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.HTV-X1 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 | 2025-11-01 06:31:21.498Z | 254.542° W | 2025-11-01 06:33:21.498Z | 1.389° NNE | 38.673° | 2025-11-01 06:35:21.498Z | 42.839° NE |
| 4 mins | 2025-11-01 11:24:21.498Z | 346.108° N | 2025-11-01 11:25:21.498Z | 10.363° NNE | 21.635° | 2025-11-01 11:28:21.498Z | 79.09° E |
| 4 mins | 2025-11-01 13:01:21.498Z | 281.1° WNW | 2025-11-01 13:02:21.498Z | 247.491° WSW | 35.182° | 2025-11-01 13:05:21.498Z | 150.075° SSE |
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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