Digital rendering of Galileo GNSS satellites. Photo: ESA

[Via Satellite 12-04-2015] The Galileo Full Operational Capability (FOC) satellites 3 and 4, assembled by OHB System AG of Germany, are now in service. The satellites are broadcasting navigation signals and have since Dec. 1 been relaying Search and Rescue (SAR) messages as part of the international Cospas–Sarsat System.

Known as Adam and Anastasia, Galileo FOCs 3 and 4 launched March 27 and underwent a lengthy test campaign.

The first pair of full satellites was placed in improper orbits in 2014 by a malfunction of their Soyuz launcher’s upper stage, but the elongated orbits have since been modified so that the navigation payloads can perform as planned. The European Commission is set to make a decision on whether they will be employed as part of the Galileo constellation. Galileo FOCs 3 and 4 were inserted into the correct orbits.

The third pair of FOC satellites launched in September 2015 and is undergoing payload testing. OHB expects this pair will enter service early next year.

The latest Galileo FOC twins, named Antonianna and Andriana, have arrived in French Guiana, aiming for a Soyuz launch on December 17. The intention is to have those satellites, Galileo FOC 7 and 8, ready to enter the operational constellation by next spring.