Angular structure of the penetration layer at an arbitrary time in simulation (a) deep2D and (b) deep3D. The penetration depth in this illustration is determined by the first zero of the vertical kinetic energy flux. The boundary between the convection zone and the stable radiative zone, calculated from the Schwarzschild criterion, is indicated by a solid black line. The vertical axis is in units of the pressure scale height h_p at this boundary. A dashed black line indicates the average penetration depth at this time. For the 3D simulation, this 2D representation is of a typical selection in ϕ.