Mars is known as the Red Planet. This nickname comes from its reddish appearance, which is caused by iron oxide, commonly known as rust, present on its surface. Mars is the fourth planet from the Sun and has garnered significant interest in scientific research and exploration, particularly regarding the possibility of past or present life. It has a thin atmosphere, mostly carbon dioxide, and features the largest volcano and canyon in the solar system. Mars has been a target for numerous spacecraft missions, both orbiters and landers, which continue to provide valuable data about the planet's geology and climate.