CNES projects library

January 30, 2020


Starting in 2022, the four small satellites in the CO3D constellation (Constellation Optique en 3D) are set to map the globe in three dimensions from low Earth orbit, serving the needs of the public and private sectors.

To succeed the stereoimaging capability provided by the Pleiades satellites (lien vers contenu anglais), CNES has conceived the CO3D programme to deliver geographic data covering the entire globe in three dimensions. To be able to map a zone of interest in 3D, four satellites are required to rapidly acquire imagery from different inclinations and track potential changes.

Each CO3D satellite will carry a unique optical instrument with a spatial resolution of approximately 50 cm. After processing on the ground, their data will yield 3D maps of all of Earth’s land surfaces in the form of a digital surface model (DSM) with an elevation resolution of approximately one metre. DSM production will cover some 25 million square kilometres annually, a rate unrivalled anywhere in the world at this level of accuracy. DSMs will be used by the military and by civil society, as well as opening up new commercial prospects for start-ups and established firms alike. The entire globe is expected to be covered in five years and for certain categories of user—like glaciologists, snow scientists or geologists—zones of interest will be remodelled every few months.

On 8 July 2019, CNES awarded the CO3D contract to Airbus Defence & Space, which will build the satellites around a new spacecraft bus weighing about 300 kilograms and equipped with electric thrusters for in-orbit manoeuvres. These highly agile satellites will use new optics to acquire imagery and have the ability to pre-process it on board and then downlink it to ground at very high data rates. Certain synergies will also be possible with the Pleiades NEO project being pursued by the manufacturer, for example by combining DSM maps with very-high-resolution imagery.


Lionel Perret : lionel.perret at