It depends on what you mean by "near." If you're looking at the planets in our solar system, here's the order they appear from the Sun:

* Mercury

* Venus

* Earth

* Mars

* Jupiter

* Saturn

* Uranus

* Neptune

So, the planets closest to Mars are Earth (when Mars is on the Earth side of the Sun) and Jupiter.

However, if you're looking at planets in terms of their average distance from the Sun, the closest planet to Mars is Earth.

Here's why:

* Earth's orbit is closer to Mars's orbit than Jupiter's.

* The planets' orbits aren't perfectly circular, so the actual distances between them vary.

It's also important to note that other objects, like asteroids and comets, might be even closer to Mars at certain times.