Conference Agenda

The goal of the CO3D (Constellation Optique 3D) mission is the full-automatic production of a worldwide accurate DSM (Digital Surface Model). This DSM is generated from stereo acquisitions obtained from a new generation of high-resolution optical satellites, called CO3D. The DSM accuracy is one meter in relative height for moderate slopes and four meters in absolute height with a one-meter grid space. Each of the four satellites of the constellation provides images with 0.50 m resolution in red, green, blue and near-infrared bands. The satellites resource is shared by, on one hand, the French institutions (government, scientists concerned by global Earth monitoring) who have dedicated access and preferred price conditions, and on the other hand, ADS (Airbus Defence and Space) customers interested in 2D and 3D products. The constellation was launched on July 26, 2025

We present the qualification of 3D products as part of the CO3D mission. The CO3D mission is dedicated to creating a digital surface model of the Earth's landmass cover. Massive automatic production is a challenge in itself, as this ground segment produces more advanced data for an optical mission. Firstly, the 3D product, which is generally retouched and checked, which can represent a significant cost. In the case of the CO3D mission, these products will be generated completely automatically. Masks will also be included to describe the processing history and provide precise information on the altitudes restored. All of this data requires detailed qualification with precise reference data and methods to best reflect its quality. The paper will describe all of these methods and data and provide an overview of the performance of these new CO3D products.

The launch of the four CO3D spacecrafts took place on 26th July 2025 aboard Vega-C from Kourou space center with Microcarb microsatellite. After a first week spent calibrating the most critical subsystems of the spacecraft, the instrument was switched on, enabling the 9-months Image Quality commissioning phase to begin. Images are acquired in RGB and NIR spectral bands with a 50 cm Ground Sampling Distance (GSD), thanks to matrix sensors based on a Bayer pattern. This brings new calibration challenges such as demosaicing and 2D line of sight determination. 3D calibration activities take place in a second stage of the commissioning phase once radiometric and geometric calibration are finalized.

This work introduces CO(ast)3D, a predictive pipeline that helps identify when upcoming CO3D satellite overpasses are likely to capture surface wave signals suitable for bathymetry acquisitions. Because CO3D cannot directly image the seafloor, depth must be inferred from the optical expression of surface waves, whose visibility depends strongly on illumination, viewing geometry, and sea state.

The pipeline combines CO3D orbital tracks with forecasted wave parameters from the Copernicus Marine model to construct a directional wave spectrum, generate a time-varying free surface through linear wave theory, and simulate CO3D-like radiance images at native spatial resolution. These synthetic scenes allow the clarity of the wave field to be evaluated a priori for any future time and location.

By predicting whether conditions will yield a sufficiently coherent wave signal, the system supports more efficient tasking, reduces acquisition risk, and improves the likelihood of capturing images suitable for accurate bathymetric inversion.

The challenges, main design elements, and results of the CODIP and ICC components will be presented in this paper, as well as the modalities for accessing and using the CO3D products.