Space EX26: how six nations tested space-domain interoperability

Portugal ran its first military exercise dedicated entirely to the space domain this September, with ICEYE’s SAR as part of the scenarios used to test it.

What was Space EX26?

Space EX26 ran from 7 to 11 September 2026 at Air Base No. 11 in Beja. Organized and led by the Portuguese Air Force's Center for Space Operations, it was the first military exercise Portugal has hosted dedicated to the space domain.

Six nations sent teams to Beja: Portugal, Spain, France, the Netherlands, the United Kingdom, and the United States, joined by one NATO representative body. Over five days, they tracked objects in orbit, managed space-domain data across borders, tested command and control together, and coordinated operations as a single group.

The Portuguese Air Force framed the exercise around two objectives: strengthening multinational cooperation and space-domain awareness through shared data, sensor capabilities, and operational knowledge, and improving interoperability in a space domain it describes as increasingly congested, competitive, and contested.

Why does sovereign SAR need to integrate with allied systems?

ICEYE's SAR satellite capability was included in the exercise scenarios, covering both sovereign, single-nation use and multinational integration between allied systems. SAR was part of the simulated scenarios participants used to test coordination between national space assets.

That distinction matters for what Space EX26 was actually testing. As more nations stand up their own SAR constellations, the question stops being whether a country can operate its own sovereign system, and becomes whether that system can also work inside a shared, multinational structure when allies need to coordinate. A sovereign SAR capability that cannot integrate easily with allied systems is a constellation on its own. One that can become a building block for a federated network, without the owning nation giving up control of its own asset.

"Space is becoming an increasingly strategic and sophisticated domain. The value of sovereign SAR capabilities, combined into a bigger, multinational picture when allies need to coordinate requires new ways of operating in a federated and collaborative way. Space EX26 showed how far that level of integration produces results in complex operations, and where we there’s further opportunities to improve" — Rui Costa, CEO, ICEYE Portugal

How did interoperability actually perform?

The primary lesson Space EX26 tested was interoperability: how sovereign space capabilities from different nations can work together in a shared operational picture without any one nation giving up control of its own assets. That is the same principle behind the federation model ICEYE has built its architecture around: national ownership first, shared capacity and coordination on top of it, not instead of it.

Participating teams reported strong operational effectiveness working across different national systems and processes in this first run of the exercise, and identified where coordination between allied space capabilities can be tightened to support faster decision-making across the group.

“The SPACE EX26 exercise is intended to be the first in an annual series, which will enable the development and validation of common procedures in the areas of Space Situational Awareness, command and control, orbital surveillance and space data management. The expected outcome is an enhanced ability to transform space data into useful information to support decision-making and operations, contributing to the development of national space capabilities and establishing Portugal as a credible partner in this field,” said Coronel Pedro Costa, Head of the Portuguese Air Force's Space Operations Center.

Part of a wider pattern

Space EX26 tested a specific layer of sovereign capability: whether sovereign SAR capability can be folded into a shared, multinational space-domain picture without compromising the owning nation's control. That’s different from ICEYE's other recent exercises. ORION 2026 and Fighter Lion both tested a live ISR Cell deployed at brigade level, looking at tactical timelines and dispersed combat support.