TAMPA, Fla. — Four-year-old small satellite maker Muon Space announced $89.5 million in new funding June 12 to scale production and acquire propulsion startup Starlight Engines, bringing a potential supply chain bottleneck in-house to support its rapid expansion.
The announcement brings the venture’s total Series B funding to $146 million, after securing $56.7 million last year.
Muon has grown its team by 50% since December to 150 employees and is “actively hiring for a large number of roles,” according to CEO Jonny Dyer, to support new facilities capable of producing 500 satellites per year in the 100–500+ kilogram class.
“We’re seeing clear demand signals from new and existing customers in both commercial and government sectors, and this expansion is designed to meet that demand and stay ahead of it,” Dyer told SpaceNews.
“By the end of 2027, we expect to be meeting demand for around 100 satellites per year. While this is part of a long-term strategy, it’s grounded in current contracts and pipeline planning.”
Building heritage
The Mountain View, California-based startup deployed its first satellite MuSat-1 in 2023, two years after its founding. The satellite was deorbited at the end of 2024 after completing its mission.
Dyer said MuSat-2, with instrumentation to support Department of Defense weather programs, remains operationally healthy after launching in 2024.
Muon’s third satellite launched in March 2025 and serves as the protoflight for FireSat, a low Earth orbit wildfire-monitoring system being developed in partnership with nonprofit Earth Fire Alliance. The next block of three FireSats were ordered in May.
“We are very excited about the early data collections and anticipate releasing a public first light soon,” he said.
Muon is also set to deploy a thermal-infrared imagery satellite for Hydrosat and three spacecraft for Sierra Nevada Corporation’s commercial radio frequency remote sensing system this year.
Other announced customers include the National Reconnaissance Office, Space Force, and Space Development Agency as Muon aims to scale significantly in the coming years after surpassing $100 million in new contracts signed in 2024.
The funding also supports the recent opening of a 12,000-square-meter production facility in San Jose, California, designed to manufacture and test satellites from raw materials to finished spacecraft.
“This marks a major expansion, making us one of the few companies capable of producing hundreds of satellites per year,” Dyer said.
“We’re now able to offer customers build-to-launch timelines measured in months — and do so at scale.”
Starlight reduces bottleneck risk
Muon’s acquisition of Starlight Engines, a three-year-old startup developing solid-propellant Hall-effect thrusters, extends the company’s vertically integrated Halo satellite platform, which also leverages infrared and radio frequency instruments built in-house.
Starlight’s zinc-fueled thruster system reduces the costs and supply chain vulnerabilities that come with more typical xenon and krypton-based systems, according to Muon.
“Propulsion remains one of the most persistent cost and supply chain challenges in satellite manufacturing,” Paul Day, Muon’s vice president of spacecraft production, said in a statement.
By bringing this technology in-house and integrating it with Halo, Day said the company “can accelerate delivery timelines while improving both schedule reliability and overall mission performance.”
Dyer said four Starlight thrusters have so far been delivered to customers in several mission areas, but none are yet in orbit.
The first Muon satellite with a Starlight thruster is slated for 2026.
The new capital, comprising $44.5 million in equity and $45 million in credit facilities, was led by early-stage investor Congruent Ventures, and included existing investors Activate Capital, Acme Capital, Costanoa Ventures and Radical Ventures. New investor ArcTern Ventures also joined the syndicate.