Moons are generally much larger than comets.

* Moons are natural satellites that orbit planets. They can be quite large, with our own Moon being a good example.

* Comets are icy bodies that orbit the Sun and can vary greatly in size.

However, there are exceptions:

* Some moons are very small. For example, Mars has two tiny moons, Phobos and Deimos, which are only a few kilometers across.

* Some comets can be relatively large. The largest known comet, Hale-Bopp, had a nucleus estimated to be about 60 kilometers across, which is larger than some small moons.

In general, though, moons are significantly larger than comets.