Orbital perturbation refers to the changes in the orbit of a celestial body caused by gravitational influences from other bodies. These influences can result from nearby planets, moons, or even the effects of non-gravitational forces like radiation pressure. Such perturbations can alter the shape, orientation, and position of an orbit over time. In the context of astronomy, understanding orbital perturbation is crucial for predicting the paths of satellites and spacecraft. It helps scientists and engineers make necessary adjustments to maintain desired orbits and ensure the successful operation of missions, such as those involving Earth observation or interplanetary travel.