Muon Space is the first company in history to test-fire a zinc-propellant Hall-effect thruster in space, writes Chris Young. The firm’s experimental propulsion system launched to orbit attached to SERT-III, a dedicated propulsion spacecraft designed and built by Muon in less than a year.

Hall-effect thrusters, the go-to for high-efficiency satellite propulsion, traditionally rely on xenon or krypton propellants that are highly expensive and require heavy high-pressure storage systems.

Muon’s Starlight thruster uses solid zinc as a propellant. Because zinc is solid at room temperature, it eliminates the need for bulky pressurised propellant tanks. It is also cheap and abundant, making it ideal for satellite manufacturers increasingly dependent on constrained noble gas supply chains. On the constellation scale, it can also lead to substantial cost reductions.

The test fire, performed on July 1, 2026, was completed successfully on the first attempt. It marked the first time a fully solid-metal propellant Hall-effect thruster system was operated in space. In an update from the company, Muon said in-orbit telemetry closely matched ground test predictions. Orbital tracking data also confirmed the thrust operation was a success.

According to Muon, the successful test “validates the company’s Starlight electric propulsion system end-to-end in the orbital environment, and establishes a new benchmark for what is possible in commercial electric propulsion.”

Muon announced its acquisition of propulsion startup Starlight Engines for an undisclosed fee in June 2025. They pioneered the solid zinc-propellant Hall-effect thruster system that Muon aims to begin deploying on customer missions by the end of 2026.

“We bet on Starlight Propulsion’s technology because it’s a game changer for a very troubled part of the space supply chain,” said Jonny Dyer, CEO of Muon Space.