* The Sun is a star. It's a giant ball of hot gas that produces its own light and heat through nuclear fusion.

* The Moon is a natural satellite. It orbits the Earth and does not have its own light. It reflects the light from the Sun.

Here's what defines a planet:

1. Orbits the Sun: A planet must orbit the Sun directly, not another object.

2. Has enough gravity to be round: A planet's gravity needs to be strong enough to pull itself into a roughly spherical shape.

3. Has cleared its neighborhood: A planet must be the dominant gravitational body in its orbital region, meaning it has cleared away most other objects in its path.

Neither the Sun nor the Moon meet these criteria.