Saturn's rings are composed of hundreds of thousands of small particles, which range in size from less than a few centimeters to several meters. The rings appear so bright in large part because they are dominated by icy materials that are highly reflective. Why did the rings form, and why are they composed of so many small particles

Saturn's rings are composed of ice because they are made of liquid-based elements that freeze to the extreme cold open space temperatures. They are formed because Saturn is a very big body of mass and big bodies of mass tend to have a strong gravitational force that attracts smaller objects. Making many of them be attracted by Saturn's gravity force but after being destroyed they remained in a small size to surround it.

Explanation:

First of all, we need to understand a few things, big bodies of mass tend to attract smaller bodies of the mass because their gravitational force makes them able to do it. Now, when they get close they collide and the smaller ones get destroyed. This is what happened to many asteroids, and moons hat became to close to Saturn. Then, because they were made of molecules that we're able to be free they froze because of the open space temperature and that allowed them to remain in that state of matter and form the rings. Also, that doesn't mean they are going to stay there forever.