Here's why:
* The Earth's Gravity: The Moon is held in orbit around the Earth due to the Earth's gravity.
* The Sun's Gravity: The Earth and the Moon together orbit the Sun due to the Sun's gravity.
Think of it like this:
* Imagine a playground merry-go-round (that's the Sun).
* Now imagine you and a friend (the Earth and the Moon) holding hands and running around the merry-go-round.
* You and your friend are still holding hands, orbiting each other, but you're both also going around the merry-go-round.
So, the Moon doesn't "circle" the Sun in the same way it circles the Earth. Instead, it follows the Earth's path around the Sun.