Mars is the fourth planet from the Sun and the seventh largest. Mars (from the greek: Ares) is the god of War. Due to its red color; Mars is sometimes referred to as the Red Planet. Mars orgit is very elliptical, and because of this, while the average temperature on Mars is about -55 C, Martian surface temperatures range widely from as little as -133 C at the winter pole to almost 27 C on the day side during summer. Except for Earth, Mars has the most highly varied and interesting terrain of any of the terrestrial planets, some of it quite spectacular: the 24 km high Olympus Mons, the huge bulge called Tharsis, the system of canyons Valles Marineris, and the impact crater Hellas Planitia.