British startup Shield Space is developing a proposal to protect satellites with coordinated swarms of small autonomous spacecraft. The company says the CubeSats could use lasers, microwaves or remote interception methods against potential threats, and continue operating even if they lose contact with controllers on Earth.
The project draws on drone-warfare concepts used on Earth. Shield Space plans to release small spacecraft from a larger vehicle in orbit and use them as interceptors for satellites considered strategically important. Cofounder and CEO Graeme Ritchie said the company aims to deploy as many as 100 CubeSats for less than £100 million, or about R$700 million.
Interest in orbital protection has grown amid concerns about close approaches between satellites. In May 2026, four Russian military satellites reportedly moved near ICEYE-X36, a commercial radar-imaging satellite widely regarded as a source of battlefield intelligence for Ukraine. One of the Russian satellites was reported to have passed within 500 meters of ICEYE-X36 in October. Such proximity could potentially interfere with communications, dazzle or damage equipment, or force a satellite to change course and use fuel.
Shield Space’s first planned demonstration, called Project Broadsword, is scheduled for the fourth quarter of 2027 and is expected to launch on SpaceX’s Transporter-21 rideshare flight. It will use an 8U CubeSat and a smaller 3U spacecraft as a target. The company intends to test whether the pair can close from an initial separation of 100 kilometers to 100 meters, while assessing four levels of autonomy, from human involvement to a mode it describes as almost fully autonomous.
The proposal is still in development. Small satellites must fit propulsion, sensors, cameras, computing systems for artificial intelligence and defensive equipment into limited space. The company has also identified constraints involving weight and power. Its founders say that real-world data for training autonomous systems is scarce and that simulations cannot yet reproduce every condition needed.
There are also questions about how an autonomous military system would follow rules governing the use of force. Bleddyn Bowen, an astropolitics specialist at the University of Durham, compared the concept with Brilliant Pebbles, a Cold War proposal for autonomous orbital interceptors. He said the technology would require years of development and testing, including ways to assess kinetic weapons without generating orbital debris.
Shield Space’s longer-term plans include demonstrations with two larger 16U CubeSats, followed by a carrier spacecraft able to transport ten satellites. The company ultimately envisions ten such carriers operating across different orbits to protect broader regions of space. For now, the planned tests will need to show whether autonomous satellites can work together and respond to threats without introducing further risks to orbit.
Sources: Olhar Digital.