Mars is the most explored planet after Earth, with rovers revealing it was once warmer, wetter, and had a thicker atmosphere

Image Credit: NASA/JPL/MSSS

Mars was named after the Roman God of war for its blood-like color; the Egyptians called it "Her Desher," meaning "the red one"

Image Credit: NASA/JPL

Mars is about half the size of Earth, with a radius of 2,106 miles; if Earth were a nickel, Mars would be a raspberry

Image Credit: NASA 

Mars has two small, potato-shaped moons, Phobos and Deimos, likely captured asteroids named after the horses of the Greek war God Ares

Image Credit: NASA/JPL-Caltech/ University of Arizona

Mars has the solar system's largest volcano, Olympus Mons, which is three times taller than Mt. Everest and as wide as New Mexico

Image Credit: NASA