Reentry dynamics refers to the study of how objects, such as spacecraft, behave when they re-enter the Earth's atmosphere. This process involves complex interactions between the object and atmospheric gases, leading to changes in temperature, pressure, and velocity. Understanding these dynamics is crucial for ensuring the safety and success of missions returning from space. Key factors in reentry dynamics include the object's shape, speed, and angle of entry, which influence the aerodynamic forces acting on it. Engineers use this information to design heat shields and other protective measures, ensuring that vehicles like the Space Shuttle or Mars rovers can withstand the extreme conditions of reentry.