Space One KAIROS
| Function | Launch vehicle |
|---|---|
| Manufacturer | Space One |
| Country of origin | Japan |
| Size | |
| Height | 18 m (59 ft) |
| Diameter | 1.35 m (4 ft 5 in) |
| Mass | 23,000 kg (51,000 lb) |
| Stages | 4 |
| Capacity | |
| Payload to LEO | |
| Altitude | 500 km (310 mi) |
| Orbital inclination | 33° |
| Mass | 250 kg (550 lb) |
| Payload to SSO | |
| Altitude | 500 km (310 mi) |
| Orbital inclination | 97° |
| Mass | 150 kg (330 lb) |
| Associated rockets | |
| Comparable | Minotaur I Pegasus Electron Ceres-1 |
| Launch history | |
| Status | In development |
| Launch sites | Spaceport Kii |
| Total launches | 2 |
| Failure(s) | 2 |
| First flight | 13 March 2024 |
| Last flight | 18 December 2024 (Active) |
The KAIROS rocket (カイロスロケット), or Kii-based Advanced & Instant Rocket System, is a Japanese solid-fuel rocket designed to launch small satellites of mass up to 250 kg to low Earth orbit and up to 150 kg to sun-synchronous orbit by the private spaceflight company Space One. It consists of 3 solid fuel powered stages and a liquid propellant upper stage.