STAR-Water-nano — Water Resistojet for Nanosatellites
OhmSpace
Plug-and-play water resistojet propulsion system for nanosatellites — achieves >200 s Isp in a 2U-compatible form factor. Developed under ESA GSTP contract; first launch Q2 2026.
Technical specifications
- Technology
- High-temperature water resistojet (2,400 K)
- Target Isp
- > 200 s
- Propellant
- Water
- Form factor
- From 2U
- Propellant mass
- From 250 g
- Total impulse
- From 500 Ns
- Power
- Up to 50 W
- Thrust
- Up to 20 mN
- Radiation resilience
- 5 krad
- Interface
- RS-422
- Development status
- ESA GSTP contract; first launch Q2 2026
About
The STAR-Water-nano is OhmSpace’s flagship compact electric propulsion unit for the nanosatellite market. It is a fully integrated, modular system based on OhmSpace’s proprietary high-temperature resistojet technology, capable of heating water propellant to 2,400 K using 3D-printed components and a low-pressure tank design. The result is a target specific impulse greater than 200 seconds — a significant performance advantage over cold-gas alternatives — while remaining non-toxic and safe to handle. From 2U, the system provides up to 500 Ns total impulse and up to 20 mN of thrust at up to 50 W input power. The product is being validated under an ESA GSTP contract and is scheduled for its first launch in Q2 2026.
Documentation
No public datasheet yet — request the datasheet / ICD from the supplier.
