ERMIS-3, an 8U CubeSat developed by the National and Kapodistrian University of Athens, has established an optical communication link with a ground station in Greece. The demonstration, supported by the European Space Agency (ESA) and conducted with optical terminals from Lithuanian company Astrolight, took place only weeks after the satellite was commissioned.
The achievement represents Greece’s first optical link with a satellite in low Earth orbit. ERMIS-3 connected with HolOGS-1, the Holomondas Optical Ground Station developed by the Aristotle University of Thessaloniki.
Optical communications use narrow laser beams rather than conventional radio-frequency signals. This can enable high data rates, but requires both terminals to acquire and continuously track each other with great precision while the satellite moves rapidly through orbit. Clouds and atmospheric turbulence can further complicate the connection.
The successful demonstration validated one of ERMIS-3’s main objectives: precise pointing, acquisition and tracking, known as PAT. The satellite carries Astrolight’s ATLAS-1 optical terminal, which operated with a corresponding terminal at the ground station.
Launched on March 30, 2026, alongside ERMIS-1 and ERMIS-2, ERMIS-3 forms part of an in-orbit demonstration program for communications technologies aimed at small satellites. Optical links could support the transmission of the increasing amounts of data produced by missions such as Earth-observation satellites, including high-resolution and hyperspectral imagery.
ESA provided technical expertise for the mission, including environmental testing and optical alignment at its European Space Research and Technology Center in the Netherlands. ERMIS-3 is part of Greece’s National Space Program, implemented by ESA on behalf of the Greek government.
ESA said the result demonstrates the potential of cooperation between industry, academia and institutions. The ERMIS investigators described the use of ATLAS-1 as a new capability for laser communications and secure communications opportunities for small satellites in Europe.
Sources: Phys.org.