the descent through the cloud layer took about 20 minutes, during which time the lander took measurements of the atmosphere and radioed the information to the orbiter. to minimize lander damage in the hot atmosphere, the parachute was released at an altitude of 50 km, and the ring-shaped aerodynamic shield provided braking. the venusian atmosphere is so dense near the surface that this shield provided a descent rate of 7 m/s as the lander touched down. the landing device, a hollow ring surrounding the lower part of the lander, was partly crushed upon touchdown to take up most of the landing impact.