What are the inner and outer planets?

How are the inner and outer planets characterized as such

In our solar system, there are 8 planets. They are divided into two groups � inner and outer planets. The inner solar system contains Mercury, Venus, Earth and Mars � the planets closest to the sun. The outer solar system contains Jupiter, Saturn, Uranus and Neptune. Once known as the ninth planet, Pluto is now classified as a dwarf planet. The inner and outer planets are separated by an asteroid belt which lies between Mars and Jupiter. Many asteroids can be found in this region of space.

The inner and outer planets are characterized by different features. The inner planets are known as terrestrial planets because they are similar to the earth in composition and in size. They have a solid surface and are composed of heavy metals, such as nickel and iron. These planets tend to have few or no moons. The Earth and Mars are the only inner planets that have moons orbiting them. One moon orbits Earth while two small moons orbits Mars. All the inner planets do not have rings orbiting them. The inner planets spin slowly when compared to the outer planets which are much larger in size. It takes the Earth 23 hours and 56 minutes to spin on its axis, the quickest of the inner planets.

The outer planets are the furthest planets from the sun. They are also known as gas giants or Jovian planets. Most of the outer planets are made of gas. They have no solid surfaces and only liquid cores. Unlike the inner planets, they are big in size. Jupiter has a diameter of 142,984 km (88,846 miles), making it the largest planet in our solar system. The outer planets might be bigger in size when compared to the inner planets but their density is much smaller mainly because the elements that make up the outer planets are less densely packed together. The outer planets spin much quicker than the inner planets. Even Uranus, the slowest planet of the outer planets, takes only 17 hours and 14 minutes to spin on its axis.

Twitter | Facebook | Contact Us | Terms of Use