Mars is the fourth planet from the sun in our solar system. It is known as the Red Planet due to its reddish appearance in the night sky. Mars is a rocky planet with a thin atmosphere and a surface dotted with impact craters, valleys, and towering volcanic mountains. It has a day-night cycle similar to Earth, with a 24.6-hour day, and its seasons are caused by the tilt of its axis. Mars is also of interest to scientists as it may have had liquid water on its surface in the past and could potentially support life.