Add to ORKGInternational audienceBased on the analysis of UV images (at 365 nm) of Venus cloud top (altitude 67±2 km) collected with VMC (Venus Monitoring Camera) on board Venus Express (VEX), it is found that the zonal wind speed south of the equator (from 5°S to 15°s) shows a con- spicuous variation (from -101 to -83 m/s) with geo- graphic longitude of Venus, correlated with the un- derlying relief of Aphrodite Terra. We interpret this pattern [1] as the result of stationary gravity waves produced at ground level by the up lift of air when the horizontal wind encounters a mountain slope. These waves can propagate up to cloud top level, break there and transfer their momentum to the zonal flow