This is a tricky question! While oxygen is the most abundant element in Earth's atmosphere, it's not as common on other planets in our solar system.

Here's the breakdown:

* Earth: Of course, Earth has an atmosphere rich in oxygen.

* Mars: There are trace amounts of oxygen in Mars's atmosphere, but it's not nearly as abundant as on Earth.

* Other planets: The atmospheres of Venus, Mercury, Jupiter, Saturn, Uranus, and Neptune are primarily composed of gases like carbon dioxide, nitrogen, and hydrogen. They have very little to no oxygen.

So, the answer is technically only Earth. While Mars has some oxygen, it's not a significant component of its atmosphere.