A Greek mountain observatory has been converted into an optical ground station to test laser communication links with CubeSats in orbit, as part of a European effort to build infrastructure that transmits data up to a hundred times faster than radio frequencies and is far harder to jam or intercept.
Lithuanian space and defence company Astrolight has completed the commissioning of the Holomondas Optical Ground Station (OGS) in Greece, developed as part of the ESA-backed PeakSat project led by the Aristotle University of Thessaloniki. The station is now supporting in-orbit demonstration missions for two Greek CubeSats — PeakSat and ERMIS-3 — which launched on 30 March 2026 as part of ESA's Greek Connectivity Programme.
Astrolight supplied both segments of the optical link for the missions: the ground station itself and the ATLAS-1 laser communication terminals installed on both satellites. The Holomondas site, originally built as an astronomical observatory, was equipped with laser communication systems including an 808-nanometer laser beacon and a C-band optical receiver capable of data reception at speeds up to 2.5 Gbps under varying atmospheric conditions.
We are happy to apply our technical expertise to commission the Holomondas station and support the Aristotle University of Thessaloniki's efforts to advance Greece's and Europe's optical communication infrastructure
Unlike traditional radio frequency communications, laser links use narrow infrared beams that can carry up to 100 times more data per second and are extremely resistant to electronic interference. The technology is being tested as a candidate for future high-capacity satellite connectivity networks, where congested radio spectrum is an increasing constraint.
Laurynas Mačiulis, CEO of Astrolight, said: "We are happy to apply our technical expertise to commission the Holomondas station and support the Aristotle University of Thessaloniki's efforts to advance Greece's and Europe's optical communication infrastructure. By providing an end-to-end communication system, with ground and space segments designed to work together from the start, we helped streamline the mission's path from integration to in-orbit testing."
Frederic Rouesnel, the ESA project manager for the Greek Connectivity programme, said the commissioning "marks an important step towards enabling faster, more secure, and resilient connectivity, while strengthening Greece's role within Europe's expanding optical communications ecosystem."
Kleomenis Tsiganis, Professor at AUTh, noted that the station is "moving closer to becoming an internationally recognized optical communication hub," crediting close collaboration between academia and industry for the progress.
Holomondas is moving closer to becoming an internationally recognized optical communication hub and contributing to the future global network of optical ground stations
