KirkwoodLücken

Kirkwood gaps are regions in the asteroid belt where there are very few asteroids. These gaps are located at distances from the Sun that are simple integer ratios of Jupiter's orbital period. For example, a gap exists at 2.5 times Earth's orbital radius, where asteroids would orbit three times for every one orbit of Jupiter. Another gap is found at 3.3 AU, where asteroids orbit four times for every one orbit of Jupiter. A third prominent gap is at 1.9 AU, where asteroids orbit twice for every orbit of Jupiter.

These gaps are caused by orbital resonance with Jupiter, the most massive planet in our solar system. When an asteroid's orbital period has a simple integer ratio with Jupiter's orbital period, the asteroid experiences repeated gravitational tugs from Jupiter at the same point in its orbit. Over long periods, these repeated tugs perturb the asteroids' orbits, pushing them out of these resonant zones and into other parts of the asteroid belt.

The existence and location of the Kirkwood gaps provide strong evidence for the gravitational influence of Jupiter on the solar system's smaller bodies. They also help explain the distribution of asteroids within the belt, showing that certain orbital distances are dynamically unstable. Studying these gaps helps astronomers understand the evolution of the solar system and the processes that shaped the asteroid belt into its current state.