JAXA / MHI · Japan · First flight 2023
Japan's next-generation flagship launch vehicle replacing the H-IIA. Features the expander-bleed cycle LE-9 engine, designed for improved reliability and reduced cost. Suffered a second-stage anomaly on its December 2025 flight after five consecutive successes.
From SpaceNexus's launch tracker (tracked since Feb 2, 2025); outcomes recorded as each flight lands. Career totals above are the vehicle's full history.
| Height | 63 m |
| Diameter | 5.2 m |
| Liftoff mass | 574,000 kg |
| Stages | 2 |
| Engines | 2x LE-9 + 0/2x SRB-3 + 1x LE-5B-3 |
| Propellant | LH2 / LOX + HTPB (SRBs) |
| Fairing diameter | 5.2 m |
| Payload to LEO | 16,500 kg |
| Payload to GTO | 6,500 kg |
| Payload to SSO | 12,000 kg |
| Payload to TLI | — |
| Reusable | No |
| First flight | 2023-03-07 |
| Last flight | Active |
| Variants seen on the manifest | H3-22, H3-24, H3-30 |
A dedicated H3 launch lists at roughly $51 million, about $3,091 per kilogram to low Earth orbit at full payload. Actual contract prices vary with orbit, integration and government requirements.
The next tracked H3 launch is Martian Moon eXplorer (MMX) on Oct 19, 2026, 19:41 UTC from Tanegashima Space Center, Japan. Dates move; Mission Control carries the live countdown.
H3 has flown 9 times with 7 successes, 2 failures and 0 partial failures — a 77.8% success rate.
16,500 kg to low Earth orbit, 6,500 kg to geostationary transfer orbit, 12,000 kg to sun-synchronous orbit.