Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, only larger than Mercury. Mars is often called the Red planet because of the effect of the Iron oxide on Mars's surface, which gives it a reddish appearance. Mars is a terrestrial planet with a thin atmosphere, with surface features like impact craters, valleys, dunes, and Ice caps.
Olympus Mons, the largest volcano and highest mountain in the Solar System is on Mars! Valles Marineris, one of the largest canyons in the Solar System, is also on Mars. The Borealis basin in the Northern Hemisphere covers 40% of the planet and might be a giant impact feature. Mars has two small potato shaped moons, Phobos and Deimos. The days and seasons on Mars are similar to Earths because the planets have a similar rotation period and tilt of the axis.