Atmospheric Entry

Atmospheric entry, sometimes called reentry when the object originated from that same planet's surface or orbit, is the passage of an object from space into and through a planet's atmosphere, a phase that subjects the object to intense heating from compression of the air ahead of it and to severe deceleration forces. Spacecraft returning to Earth manage this heating with ablative or reusable thermal protection systems and by shaping their trajectory to control the deceleration profile, while natural objects such as meteoroids often disintegrate entirely before reaching the surface. Successful crewed entry requires precisely controlling the entry angle, since too shallow a path risks skipping back into space while too steep a path generates unsurvivable heating and deceleration.