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 shape, 14.5 m
Radar Cross Section
RCS unknown
Expand to show TLE details & historyLast TLE update: 1 day ago
TLE from 1 day ago
0 HTV-X1
1 66174U 25241A 25311.19511068 .00011482 00000-0 21019-3 0 9993
2 66174 51.6334 318.4356 0005155 25.9626 334.1621 15.49813276 1450Epoch: 2025-11-07T04:40Z
TLE epoch observation values (Epoch: 2025-11-07T04:40:57.562Z)
Latitude
0°
Longitude
-158.4468°
Altitude
414.86 km
Speed
7.665 km/s
True Right ascension
21h 13m 44s
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
06:57:03
Azimuth
Unknown
Elevation
Unknown
Doppler factor
Unknown
Orbital elements
Apogee altitude
421.284 km
Perigee altitude
414.278 km
Semi-major axis
6,795.918 km
Eccentricity
0.00052
Inclination
51.6334°
RAAN
318.4356°
Arg. of periapsis
25.9626°
True anomaly
334.13634°
Mean anomaly
334.1621°
Eccentric anomaly
334.14922°
Mean motion
3.8741 °/min
Orbital period
92.92 mins
BSTAR
0.00021019
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Other satellites on launch #241 in the year 2025 (2025-10-26 UTC)
No other RSOs were in this launch
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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.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. |
|---|---|---|---|---|---|---|---|
| 5 mins | 2025-11-09 03:19:00.682Z | 245.198° WSW | 2025-11-09 03:21:00.682Z | 302.076° NW | 41.891° | 2025-11-09 03:24:00.682Z | 46.69° ENE |
| 5 mins | 2025-11-09 09:49:00.682Z | 291.988° WNW | 2025-11-09 09:51:00.682Z | 216.446° SW | 38.945° | 2025-11-09 09:54:00.682Z | 144.001° 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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