NEWS
Pale Blue Successfully Operates Water Ion Thruster and Water Resistojet Thruster in Orbit on JAXA’s RAISE-4
CHIBA, Japan (Apr.21) – Pale Blue successfully operates water ion thruster and water resistojet thruster in orbit on JAXA’s RAISE-4.
Pale Blue has successfully achieved in-orbit operation of its proprietary water ion thruster and water resistojet thruster aboard the Japan Aerospace Exploration Agency (JAXA) technology demonstration satellite, RApid Innovative payload demonstration SatellitE-4 (RAISE-4). Pale Blue confirmed that both systems operated correctly and generated the expected thrust in space. Following previous successful operations on commercial satellites, this achievement on a JAXA-led mission further solidifies the flight heritage and reliability of Pale Blue’s products in space.
Launch via Rocket Lab’s Electron
The RAISE-4 satellite, equipped with Pale Blue’s propulsion systems, was launched in December 2025 from Rocket Lab’s Launch Complex 1 on the Mahia Peninsula, New Zealand, aboard an Electron rocket. This successful launch demonstrates that Pale Blue’s products are fully compatible with the environmental requirements of major global launch service providers, offering users a wider range of options for their launch vehicle selection.
About JAXA’s RAISE-4
RAISE-4 (RApid Innovative payload demonstration SatellitE-4) is a JAXA satellite designed to provide in-orbit demonstration opportunities for technologies developed by the private sector and other entities. Pale Blue proposed “KIR-X,” a propulsion module featuring both a water ion thruster and a water resistojet thruster, which JAXA selected as one of key demonstration themes. After passing stringent qualification tests, KIR-X was integrated into RAISE-4 for its orbital mission.
About in-orbit operation of Pale Blue products
Pale Blue Confirms “Rapid Startup” Capability of PBI Water Ion Thruster in Orbit, Releases White Paper (Jan 20, 2026)
https://pale-blue.co.jp/news/1296/
Water Ion Thruster achieves historic in-orbit success (Sep 10, 2025)
https://pale-blue.co.jp/news/946/
Pale Blue successfully operates the PBR-10 in orbit, confirms the soundness of the system (May 29, 2025）
https://pale-blue.co.jp/news/640/
In-orbit operation verified again after 2 years in LEO – Pale Blue’s water-based propulsion system ran on a nanosat (Mar 05, 2025）
https://pale-blue.co.jp/news/578/
Pale Blue successfully operates its water-based propulsion system in orbit (Mar 13, 2023）
https://pale-blue.co.jp/news/314/
About Pale Blue
Pale Blue develops and manufactures propulsion systems (engines) for small satellites, providing highly reliable solutions to satellite integrators and operators worldwide. Since its founding in 2020, Pale Blue has successfully achieved in-orbit operations for a number of propulsion systems, building a proven track record of performance in space. Under rigorous quality control and efficient production processes, Pale Blue has established a mass production system at its cutting-edge in-house facility to meet the growing global demand. Pale Blue is committed to creating mobility that is core to the space industry, leading the next generation of space development, ranging from Low Earth Orbit to deep space.
Website：https://pale-blue.co.jp/