The inner and outer planets all follow an elliptical orbit, share the same orbital plane, are spherical and contain some of the same elements. Besides those attributes, each planet is very different.
The inner planets are those that exist between the sun and the asteroid belt. They are:
The outer planets are those that are between the asteroid belt and the end of the solar system. These are:
The outer planets are known as Jovian or gas giants. They are much larger in size than the inner planets and are primarily composed of gases that surround a liquid metal core.
The inner planets are all smaller and denser than the outer planets. They are mostly solid and composed of rock rather than gas.
The reason for the difference in the size, density, and composition of the planets is that the gravity of the sun tends to attract heavier, solid elements, such as heavy metals, while lighter gases, such as hydrogen, helium, nitrogen, and oxygen, are not pulled as strongly inward.
The elements that exist in all of the planets are iron and nickel. Mercury, the planet closest to the sun, is almost entirely made of these two elements, while the outer planets only have trace amounts located in their core.Learn More
The distance between Saturn and Uranus varies based on where the planets are in their orbits around the sun, but averages 9.6 astronomical units. This translates to about 2.3 billion miles.Full Answer >
Jupiter is the heaviest planet in the solar system, with a mass of 1.90 x 10^27 kg. The gas giant's mass is equivalent to about 318 Earths. Jupiter is so heavy that it's twice as heavy as all the planets in the solar system combined.Full Answer >
When Pluto has an atmosphere, it is thought to be made up of methane, nitrogen and carbon monoxide in gaseous form. This atmosphere outgases from the ice on Pluto's surface when it is closest to the sun, which warms the planet and causes the ice to sublimate.Full Answer >
Mars received its name from the god of war in Roman mythology, Mars. Because the planet appeared red, it reminded the Romans of blood shed during battle. The ancient Greeks also named the planet after their god of war, Ares.Full Answer >