Planetary capture

Imagine that planets are like toys that are floating around in space. Sometimes these toys bump into each other and start playing together, while other times one toy is strong enough to pull the other one into its orbit and play with it all by itself. This is called planetary capture.

So, let's say there is a big planet like Jupiter that is playing around in space. As it moves around, it might come across smaller planets or asteroids floating around. If Jupiter is strong enough, it can use its gravity to pull these smaller objects towards it. When this happens, the smaller objects start orbiting around Jupiter and become its moons.

Another way planetary capture can occur is if there are two planets that are moving towards each other. If one planet is bigger and stronger than the other, it can pull the smaller one towards it and capture it into its orbit. The smaller planet then becomes a part of the bigger planet's system.

Overall, planetary capture is just like when you bring a new toy into your toy box and it becomes a part of your playtime. The bigger toys have a stronger "gravity" and can attract smaller toys into their play space.