There are planets in the Solar System.
Solar System . is the gravitationally bound system comprising the Sun and the objects that orbit it , either directly or indirectly.The natural satellites ( moons ) orbiting the Solar System 's planets are an example of the latter . The four smaller inner planets , Mercury , Venus , Earth and Mars , are terrestrial planets , being primarily composed of rock and metal . The two largest , Jupiter and Saturn , are gas giants , being composed mainly of hydrogen and helium ; the two outermost planets , Uranus and Neptune , are ice giants , being composed mostly of substances with relatively high melting points compared with hydrogen and helium , called volatiles , such as water , ammonia and methane .