Jupiter’s moons
Why does Jupiter have so many moons?
Gravity’s reach grows with mass, and Jupiter has more of it than anything in the solar system except the Sun. A wide region around it is a place where a small body stays with Jupiter instead of orbiting the Sun on its own.
A planet that acts like a small system
The same falling-and-missing that keeps Earth beside the Sun keeps Io beside Jupiter. More mass, stronger pull at a given distance, a larger volume of space where “beside Jupiter” wins over “beside the Sun.”
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Captured crowds and a few giants
The four Galilean moons are worlds. Many of the rest are captured asteroids on long, often backward orbits. Counting “how many moons” is then a census of what telescopes can still see, not a closed number.