CNES projects library

July 26, 2023

ELISA

From 2011 to 2021, four French satellites flew in formation at an altitude of 700 kilometres, recording electromagnetic signals from ground radars. The goal was to show that such radars could be pinpointed with a high degree of precision. France was the only European country to trial this technology.

Initiated by the French Ministry of Defence, ELISA (ELectronic Intelligence SAtellite) was a system demonstrator. Its objective was to show that it was possible to locate radar equipment around the world from space and gather intelligence on their technical characteristics. Space does not belong to any nation, 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 were built around the Myriade spacecraft bus, developed by CNES for its science missions. CNES oversaw the project with the French defence procurement agency (DGA) and also operated the four satellites from the ground.

The mission concluded successfully on 31 July 2021. The lessons learned from ELISA paved the way for the CERES programme, comprising three satellites launched on 21 November 2021. With CERES, France has joined the select circle of space powers with a satellite-based signals intelligence capability.