The inner planets of the solar system are all relatively close to the sun. They are also all relatively similar to each other in size, mass, density and other physical properties. Unlike the outer planets, the inner planets are small, dense and warm.Know More
The four inner planets of the solar system are, in order, Mercury, Venus, Earth and Mars. All four of these worlds are small compared with the four gas giants that are the outer planets, and they are relatively dense. The four inner planets are much closer to the sun than the outer planets, so they receive considerably more light and are consequently much warmer. None of the four inner planets have rings, while all four outer planets do.
In contrast to the gas planets, the four terrestrial planets all have thin, tenuous atmospheres. Planetary atmospheres can be either reducing, which means dominated by hydrogen, or oxidizing. The inner planets have oxidizing atmospheres, as the solar wind long ago blew the light hydrogen gas away from their surfaces. Their thin atmospheres and close proximity to the sun give the inner planets wide temperature ranges. Unlike Jupiter, which maintains a fairly stable temperature from the daytime side of the planet to the night, the terrestrial planets are significantly colder on their night sides than on the hemispheres facing the sun.Learn more about Planets
The surface temperatures of the solar system's planets are dependent on how close each planet is to the sun. Planets that have atmospheres are better able to retain heat from the sun, affecting the planet's surface temperature.Full Answer >
In order to be declared a planet, a celestial body must meet the following qualifications: It must orbit the sun, it must maintain a nearly spherical shape and have the necessary mass for self-gravity so that it does not succumb to rigid body forces, and it must clear the neighborhood around its orbit. All recognized planets in the solar system meet this definition.Full Answer >
The inner planets, Mercury, Venus, Earth and Mars, are made up of silicate rock and heavy metals such as iron and nickel, whereas the outer planets, Jupiter, Saturn, Uranus and Neptune, are made up mostly of gases, according to Universe Today. The outer planets are subdivided into gas giants, comprised mostly of hydrogen and helium, and ice giants, comprised mostly of methane, ammonia and water.Full Answer >
The eight planets of the solar system are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. The four inner planets are terrestrial worlds, while the outer solar system consists of four gas giants sometimes known as the Jovian planets.Full Answer >