Cartoon of UGC 6697 under the action of ram pressure due to its fast motion through the ICM. Its front (shaded) is already completely depleted of gas. The velocity of the gas is shown to follow the velocity curve of the stars. Velocities are given normalized to zero in the center. Some gas originally belonging to a central region has been displaced to the NW by ram pressure, retaining its original velocity (− 50 km s^-1). This cloud overlaps spatially with another gas cloud in the background arm, with a velocity of 200 km s^-1. An observer who looks at the galaxy almost edge on collects a spectrum carrying multiple velocity components along the NW tail.