This is a bit of a trick question! Planets don't actually overlap in the way we think of objects on Earth overlapping.

Here's why:

* Planets orbit the Sun: They follow paths called orbits, and these orbits are all at different distances from the Sun.

* Orbital Paths: While the orbits can be close, they are never actually overlapping. Think of it like lanes on a highway: cars in different lanes are close, but they don't drive on top of each other.

So, the answer is none!