Mars is the second smallest planet in the solar system nicknamed the "Red Planet" due to its iron-rich soil. It has the largest volcano in the solar system called Olympus Mons, which is over 3 times taller than Everest. Mars also has two small moons called Phobos and Deimos and an atmosphere that is 100 times less dense than Earth's but can still support weather. While no current life has been found, water ice exists on Mars and research continues to understand if it could support human habitation.