Two New Satellites Successfully Join Galileo SatNav Constellation

Europe’s Galileo SatNav system has received a boost with the addition of two new satellites to its existing network. The total number of satellites in the Galileo Network is now 16 (including these two). These two satellites are part of the the four Galileos that were launched by Ariane 5 on 17 November. The new satellites will now accordingly broadcast timings and navigate signals worldwide while also picking up distress calls across the planet.

The growing number of Galileo users around the world will draw immediate benefit from the enhanced service availability and accuracy brought by these additional satellites.

The launch into space and the maneuvers to reach their final orbits still left a lot of rigorous testing before the satellites could join the operational constellation. Their navigation and search and rescue payloads had to be switched on, checked and the performance of the different Galileo signals assessed methodically in relation to the rest of the worldwide system.

The lengthy testing saw the satellites being run from the second Galileo Control Centre in Oberpfaffenhofen, Germany, while their signals were assessed from ESA’s (European Space Agency) REDU Centre in Belgium, with its specialized antennas. The tests measured the accuracy and stability of the satellites’ atomic clocks, essential for the timing precision to within a billionth of a second as the basis of satellite navigation – as well as assessing the quality of the navigation signals.

Oberpfaffenhofen and REDU were linked for the entire campaign, allowing the team to compare Galileo signals with satellite telemetry in near-real time. Making the tests even more complicated, the satellites were visible for only three to nine hours a day from each site.

The satellites are now broadcasting working navigation signals and are ready to relay any Cospas - Sarsat distress calls to regional emergency services. Now that these two satellites are part of the constellation, the remaining pair from the Ariane 5 launch is similarly being checked to prepare them for service.