Mars is in the Solar System.
The four smaller inner planets , Mercury , Venus , Earth and Mars , are terrestrial planets , being primarily composed of rock and metal .	Mercury	Mercury (planet)	Venus	Venus	Earth	Earth	Mars	Mars	planets	List of gravitationally rounded objects of the Solar System#Planets
Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System , after Mercury .	Sun	Sun	planet	planet	Solar System	Solar System	Mercury	Mercury (planet)
