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How does gravity affect a ballistic missile after its rocket engine stops?

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rocket and missile system U.S. soldiers firing an FGM-148 Javelin antitank guided missile during training in Grafenwöhr, Ger., 2006.

After the rocket engine of a ballistic missile shuts down, the missile enters a phase of unpowered flight known as the midcourse phase, followed by the terminal phase. During these stages, the missile follows a trajectory determined primarily by the laws of physics, specifically gravity and inertia.1

Once the engine stops, the missile is no longer being propelled; it coasts along a path where gravity acts as the primary force pulling the payload toward the Earth. In the midcourse phase, the payload travels along a ballistic path, often outside the atmosphere. As the missile enters the terminal phase, gravity pulls the reentry vehicles back into the atmosphere and down toward the target area.1

Guidance systems account for these gravitational forces by predicting their effect on the missile's flight path during the boost phase, ensuring that when the engine is shut off, the missile is placed on the precise trajectory required to reach its intended target.1