The European Space Agency has ordered four additional Galileo Second Generation satellites, bringing the number under contract to 16. The October 27, 2026 announcement assigns two spacecraft to Thales Alenia Space in Italy and two to Airbus Defence and Space in Germany. Delivery of the additional satellites is planned for 2031, with launches afterward.
The orders extend contracts awarded in 2021, when each manufacturer was selected to build six satellites. ESA signed the new agreements with Thales Alenia Space in Rome on October 23 and Airbus in Ottobrunn on October 26. The additional spacecraft will form part of the continuing replacement and expansion of Europe’s satellite navigation infrastructure.
Galileo provides signals that receivers use to calculate position and time. Satellites broadcast timing information and data describing their orbital positions. A receiver compares signals from multiple satellites to determine its location and correct the difference between its own clock and the system’s time reference.
What the New Generation Changes
The Galileo Second Generation design introduces digital navigation payloads, improved atomic clocks and antennas, and electric propulsion. Digital payloads provide greater flexibility to change how navigation signals are generated and transmitted after a satellite enters service.
That flexibility matters because a navigation satellite operates for years after launch. Reprogrammable equipment allows supported functions to be adjusted during its operating life rather than requiring every change to wait for a replacement spacecraft.
Better clocks and signal-generation equipment support the timing measurements on which positioning depends. These improvements concern the performance of the navigation system itself. Signal authentication addresses a related but separate question: whether navigation data originated from the expected source and has been altered. New Space Economy’s explanation of Galileo signal authentication describes that distinction.
Direct Connections Between Satellites
Second-generation spacecraft will also carry inter-satellite links that exchange timing and location information directly between satellites. These connections supplement communications with ground facilities.
ESA’s inter-satellite link testing report describes two steerable terminals on each satellite. The terminals change their pointing direction as the relative positions of spacecraft change. Their pointing mechanism is designed to redirect the antenna approximately every 40 seconds.
Beyond Gravity in Switzerland tested the mechanism through 15 million reorientations during a seven-month campaign completed in March 2026. The test addressed the repeated movement required over the equipment’s operating life.
Direct exchanges between spacecraft can distribute navigation information through the constellation. Ground control will continue monitoring the satellites and supplying corrections. The links add another means of sharing information within that system.
Connecting Spacecraft and Ground Control
Introducing a new generation also requires compatible ground equipment and operating procedures. ESA reported a ground-to-spacecraft compatibility test conducted on July 3, 2026, between the Galileo control center in Oberpfaffenhofen, Germany, and a Thales Alenia Space satellite model in Rome.
Operators transmitted commands, activated the navigation payload and received telemetry describing the spacecraft equipment’s condition. The exercise tested interaction between the control system and representative satellite hardware before flight.
Thales Alenia Space, GMV and Thales SIX GTS are involved in the ground-system upgrades supporting the transition. The new satellites are intended to operate alongside the first-generation constellation.
ESA’s schedule places integration and flight testing in 2027 and the first second-generation launch in 2028. The four newly ordered spacecraft belong to a later delivery batch, scheduled for 2031, extending production beyond the initial 12 satellites.
