Mars Entry, Descent & Landing

The 7 Minutes of Terror: From atmosphere entry at 125 km altitude and 5.5 km/s, the spacecraft must decelerate to a gentle landing in about 7 minutes. The entire sequence is autonomous — light-speed delay to Earth is 4-24 minutes, so no real-time control is possible. Entry angle is critical: too steep (< -17 deg) means excessive heating and burnup; too shallow (> -12 deg) means skipping off the atmosphere back into space.