Centre National d'Études Spatiales

Magnetohydrodynamic drag on an oscillating sphere in a rotating spherical cavity

Oscillating-sphere drag is a classical fluid-mechanics problem, yet no theory simultaneously accounts for confinement, rotation, viscosity and magnetic fields. We consider a conducting sphere undergoing translational oscillations inside a rotating spherical cavity, modelling conf...

Reflector‐Free, Highly Confined Love‐Like SAWs Enabled by a Phononic Metasurface for Real‐Time Monitoring of Cell Dynamics

ABSTRACT Surface acoustic wave (SAW) devices are widely used in sensing and biosensing but generally suffer from strong attenuation in liquid environments. Conventional approaches rely on reflectors to reduce these losses, yet these components remain difficult to optimize: limite...

Uncertainties of GRACE/GRACE-FO Satellite Gravimetry Data and Thereof Derived Products

Abstract Inter-satellite ranging by space gravimetry missions, such as from the Gravity Recovery And Climate Experiment (GRACE) mission and its successor mission GRACE Follow-On, has been established to observe mass variations in the Earth system from space globally. A complex pr...

Enhancing Photogrammetric Digital Surface Models with Pretrained Diffusion Models and Multimodal Conditioning

Large-scale Digital Surface Models (DSMs) can be produced cost-effectively from satellite images via stereo-photogrammetry. However, the resulting 3D maps are often contaminated by noise, outliers, and voids. On the other hand, aerial LiDAR provides high-accuracy elevation measur...

Effects of radiative heat transfer on premixed spherically expanding NH3-air flames

This article numerically investigates the effects of radiation on the laminar burning velocity (LBV) extrapolated from microgravity spherical expanding NH 3 /air premixed flames, with equivalence ratios and pressures ranging from 0.7 to 1.3 and 1 to 50 atm, respectively. The simu...

Space circular economy: planned experimental approaches for spacecraft solar arrays

Abstract The space industry aims to promote economic growth while ensuring a sustainable use of space. The sustainability objectives of space often refer to the cleaning of space debris via Active Debris Removal missions. Those solutions, despite being needed, are unsustainable a...

Evaluate the impact of a 4 h tandem phase on the continuity of nadir altimetry measurements between S3 and S3NG-T

Abstract. The upcoming Sentinel-3 Next Generation Topography (S3NG-T) mission, designed to succeed the current Sentinel-3 (S3) mission, will operate on the same ground tracks as the current S3 constellation to maximise continuity of measurements, but with a fixed 4 h temporal lag...