World’s first zinc Hall-effect thruster fires in space on its maiden attempt

A satellite has fired a Hall-effect thruster fueled by solid zinc in orbit for the first time, giving spacecraft designers a new option for electric propulsion. Muon Space completed the test on July 1 aboard SERT-III, a dedicated propulsion test spacecraft. The mission tested the company’s Starlight propulsion system under real orbital conditions. The thruster fired successfully on its first attempt. Telemetry matched ground-test predictions, while orbital tracking detected a measurable change in the spacecraft’s trajectory. Zinc aims at xenon Hall-effect thrusters have become a standard choice for efficient satellite propulsion. Most systems use xenon or krypton, which require high-pressure storage and add complexity to spacecraft designs. Starlight takes a different approach. Its propellant comes as solid zinc, which remains stable at room temperature and does not need a pressurized tank. That could simplify spacecraft integration and ground operations. Zinc also costs less than traditional noble-gas propellants and has a much broader supply base. Those factors matter as satellite operators deploy larger constellations. Cutting propulsion hardware and propellant costs can become significant when the same system flies across dozens of spacecraft. Muon says Starlight can support orbit raising, station keeping, and controlled deorbiting on small and medium-sized satellites. The system also addresses a practical challenge that has followed electric propulsion for years. Satellite operators need efficient thrusters, but propulsion hardware must also fit tight spacecraft mass and integration constraints. SERT-III tests hardware Muon designed SERT-III specifically to examine how the propulsion system behaves in space. The spacecraft carried sensors to measure performance, spacecraft interactions, and material deposited by the thruster plume. Ground testing had already established expected performance across different throttle levels and operating conditions. The orbital test provided a chance to see whether those results held up in microgravity. They did. The thruster fed and vaporized zinc reliably during the firing, according to Muon. Tracking data also confirmed that the spacecraft experienced the expected thrust. Engineers also watched for unwanted zinc deposition around the spacecraft. Thermoelectric Quartz Crystal Microbalance sensors detected less deposition near the thruster than conservative preflight models predicted. That result gives engineers more data for understanding how zinc behaves after leaving the thruster. It should also help refine plume and contamination models for future spacecraft. Muon CEO Jonny Dyer called the orbital firing a major milestone for electric propulsion. He said the company chose to acquire Starlight Propulsion because zinc could address persistent problems in the propulsion supply chain. The test also avoided putting experimental hardware on a primary customer mission. SERT-III gave engineers a spacecraft dedicated to collecting propulsion data without placing another mission at risk. Customer missions next Muon now plans to incorporate the flight data into further development of Starlight. Engineers will focus on reliability, manufacturing, and plume management as the system moves toward production. The company expects its current-generation thruster to reach customer spacecraft before the end of 2026. Muon is also developing a larger second-generation system. It plans to test Gen2 in orbit during the first quarter of 2027. That version will target larger spacecraft and could expand zinc-based Hall propulsion beyond the smaller satellite market. If the upcoming tests confirm the early results, solid-metal propellant could become a practical alternative for more commercial spacecraft.Get the latest in engineering, tech, space & science - delivered daily to your inbox.Aamir is a seasoned tech journalist with experience at Exhibit Magazine, Republic World, and PR Newswire. With a deep love for all things tech and science, he has spent years decoding the latest innovations and exploring how they shape industries, lifestyles, and the future of humanity.