This New Space Thruster Outperforms Hydrazine

Rubicon Space Systems has completed a major hot-fire test campaign for its Velox 5-newton spacecraft thruster and is now moving the engine toward production and flight missions. Velox uses ASCENT, also known as AF-M315E, a low-toxicity monopropellant originally developed by the U.S. Air Force Research Laboratory as a higher-performance alternative to hydrazine. During the latest vacuum testing campaign in Huntsville, Alabama, Rubicon tested the thruster across a wide operating envelope, including feed pressures ranging from 25% of nominal to 125% and duty cycles from 1% to 100%. According to Rubicon, the Velox thruster was qualified for nearly 14 kilograms of propellant throughput. The company says this is the highest publicly reported throughput for a 1-newton or 5-newton ASCENT monopropellant thruster. The engine also demonstrated a specific impulse of approximately 255 seconds. Rubicon says that is nearly 10% higher than comparable hydrazine thrusters, although performance varies depending on the specific hydrazine engine being compared. NASA data confirms that ASCENT combines higher specific impulse with substantially greater propellant density than hydrazine. ASCENT is around 45–46% denser than hydrazine. That means a spacecraft can carry more propellant in the same tank volume, potentially increasing total maneuvering capability without increasing the physical size of the propulsion system. NASA has previously estimated roughly a 50% increase in maneuvering capability for a given propellant volume. Lower toxicity is another major advantage. Hydrazine requires strict handling procedures and specialized protective equipment. ASCENT significantly reduces those ground-handling requirements, potentially simplifying spacecraft processing and lowering operational costs. Rubicon had already secured a contract from an aerospace prime contractor for Velox flight hardware earlier in 2026. The company is now producing thrusters for multiple customers, with the first deliveries expected in 2027 and orbital missions planned from late 2027 onward. The company is also working with NASA on other ASCENT technologies. Rubicon supplied the chemical propulsion system for NASA’s Green Propulsion Dual Mode mission, which combines chemical and electric propulsion using the same ASCENT propellant architecture. The mission is currently planned for 2026. Rubicon has also received NASA-backed work on larger ASCENT thrusters, including development of a 110-newton prototype. For satellites that need frequent orbit changes, collision avoidance, rapid repositioning or extended mission life, higher-density and lower-toxicity propulsion could become increasingly important. Could ASCENT finally become a practical successor to hydrazine? Subscribe to Xenon Lab News for more space technology, propulsion and engineering breakthroughs. #Rubicon #Velox #ASCENT #SpacePropulsion #RocketEngine #Satellite #GreenPropellant #Hydrazine #NASA #SpaceTechnology #Spacecraft #RocketTechnology #Aerospace #FutureSpace #ScienceNews #TechNews #XenonLabNews