CNES projects library

August 6, 2021


Since 2011, four French satellites have been flying in formation at an altitude of 700 kilometres and recording electromagnetic signals from ground-based radars. The goal is to show that the positions of these radars can be pinpointed with a high degree of precision. France is the only European country trialling this technology.

Initiated by the French Ministry of Defence, ELISA (ELectronic Intelligence SAtellite) is a system demonstrator. Its objective is to show that it is possible to locate radar equipment in countries around the world from space and gather intelligence on their technical characteristics. Space does not belong to any nation, which is a huge advantage for this type of mission. Satellites can fly over all regions of the world with no restrictions, unlike aircraft or surface vessels.

The four ELISA microsatellites were launched in December 2011 and positioned just a few kilometres apart in a low-Earth orbit. They are built around the Myriade spacecraft bus, developed by CNES for its science missions. CNES is overseeing the project with the French defence procurement agency (DGA) and also operates the four satellites from the ground.

The lessons learned from ELISA are paving the way for the future CERES programme, which will comprise three satellites, scheduled to launch in 2020. With CERES, France will enter the select circle of space powers with a satellite-based signals intelligence capability.