This video of thumbnail images from the Mars Descent Imager (MARDI) on NASA's Curiosity rover shows the heat shield dropping away from the rover on Aug. 5 PDT (Aug. 6 EDT). It covers the first 25 seconds of MARDI observations as Curiosity descends toward the surface of Mars, starting about two and one-half minutes before touchdown. The video starts in darkness because there is no illumination inside the aeroshell. It starts about six seconds before heat shield separation (sometimes called heat shield jettison). About one-quarter of the way into this video, the heat shield starts to move away from the rover and back shell, and sunlight illuminates the inside surface of the heat shield. Over the course of the next 19 seconds, we see the heat shield falling away from the lander as the lander rapidly slows under the parachute. The heat shield is 15 feet (4.5 meters) across. The range to the heat shield increases from less than 3 feet (a meter) when it first starts to move to several hundred feet (meters) at the end of the video. The video runs at four frames per second.