H-2A R/B
NORAD 42739
Rocket Body
MEO
2017-028B
CONNECTING…
MEO · NORAD 42739
NOW PASSING OVER
Calculating position…
—
Altitude (km)
—
Speed (km/s)
—
Latitude
—
Longitude
🛰️ Orbital Parameters
Perigee
322 km
Apogee
33727 km
Inclination
31.4°
Period
593.8 min
Mean Motion
2.42495638 rev/day
TLE Epoch
2026-06-25 22:00:00 UTC
📐 Computed Orbital Characteristics
Avg. Altitude17,025 km
Orbital Velocity14,860 km/h
Velocity4.13 km/s
Orbital Period9 hours 54 minutes
Orbits / Day2.42
Eccentricity0.7139
Semi-Major Axis23,396 km
Est. Orbital LifetimeEffectively permanent — above atmospheric drag
🚀 Launch & Identity
Country / Operator
🇯🇵 Japan
Launch Date
2017-06-01
Launch Site
TNSTA
Int'l Designator
2017-028B
Object Type
Rocket Body
RCS Size
Large (>1 m²)
📖 About This Object
H-2A R/B is a spent rocket body associated with Japan, launched on 2017-06-01 from TNSTA on the QZSS 2 launch. It orbits in Medium Earth Orbit (MEO) at altitudes between 322 km and 33,727 km with an inclination of 31.4°. It travels at approximately 14,860 km/h (4.13 km/s), completing one full orbit every 9 hours 54 minutes — that’s roughly 2.42 orbits per day. Its orbital eccentricity of 0.7139 gives it a noticeably elliptical path, with significant altitude variation between perigee and apogee. Spent rocket bodies like H-2A R/B are among the largest pieces of uncontrolled space debris and are priority targets for collision avoidance manoeuvres and future active debris removal efforts.
🌍 Orbit Context
H-2A R/B orbits at an average altitude of 17,025 km in Medium Earth Orbit, the region between LEO and GEO (2,000–35,786 km). MEO’s higher altitude gives each satellite a much larger ground footprint than LEO, meaning fewer spacecraft are needed for global coverage — but signal latency is higher and radiation from the Van Allen belts is a significant design constraint. Within ±50 km of H-2A R/B’s average altitude, there are currently 0 active payloads and 9 tracked debris or rocket body fragments. This is a relatively sparse altitude band, containing less than 1% of all active satellites. With an inclination of 31.4°, H-2A R/B passes over latitudes between 31.4°N and 31.4°S, covering the tropical and temperate zones where most of the world’s population resides. Low-to-mid inclination orbits are efficient to reach from equatorial and mid-latitude launch sites. Japan operates approximately 190 active satellites in total.
🔗 Spent Rocket Body
This is a spent rocket body — the upper stage of a launch vehicle that remains in orbit after delivering its payload. Rocket bodies are a significant contributor to the space debris population. Older stages often retained residual propellant that could later explode, creating debris fields. Modern guidelines require upper stages to either deorbit (controlled re-entry) or passivate (vent residual fuel) to reduce fragmentation risk. The FCC's 5-year deorbit rule and UN debris mitigation guidelines are increasingly enforced to address this growing problem.
❓ Frequently Asked Questions
H-2A R/B orbits in Medium Earth Orbit (MEO) at altitudes between 322 km (perigee) and 33,727 km (apogee), with an average altitude of approximately 17,025 km. It completes one orbit every 9 hours 54 minutes, travelling at approximately 14,860 km/h (9,233 mph).
H-2A R/B (NORAD ID 42739) is a spent rocket body — the upper stage of a launch vehicle attributed to Japan. It no longer serves a functional purpose but continues to orbit Earth as tracked debris. Spent upper stages are among the largest uncontrolled objects in orbit and are closely monitored for collision risk.
H-2A R/B was launched on 2017-06-01 from TNSTA. At its current altitude, the estimated remaining orbital lifetime is: effectively permanent — above atmospheric drag. View the full satellite launch log.
Yes — Orbital Radar tracks H-2A R/B (NORAD ID 42739) using the latest TLE (two-line element set) data from Space-Track and CelesTrak. Open the live tracker to see its current position, altitude, speed and orbital path updated in real time. You can also browse the satellite directory to find other tracked objects.
H-2A R/B travels at approximately 14,860 km/h (9,233 mph) — roughly 4.13 km/s. It completes 2.42 orbits per day, meaning the crew or instruments aboard (if any) would experience approximately 5 sunrises and sunsets every 24 hours.