The inner planets are composed of rock and metals, and possess a solid surface not found in the gas giants of the outer solar system. Mercury, Venus, Earth and Mars are the four planets closest to the Sun, and all have m... More » Science Astronomy Planets

Earth formed around 4.54 billion years ago and is the third planet from the Sun. It is the fifth largest planet in the solar system and the largest of the terrestrial planets. It is also the densest of all the planets. More »

One interesting fact about Earth is its status as the fifth planet in terms of size but the densest of all. It also ranks as the largest of the terrestrial planets in the solar system and the only one on which water exis... More » Science Earth Science

According to Universe Today, the four outer planets of the solar system are all gas giants. This means they lack a conventional surface, and are made up of dense gases around a possible rocky or metallic core. These plan... More »

The interiors of the Jovian planets, also known as gas giants, are different because of their sizes. Jupiter and Saturn, the largest of the four Jovian planets, are massive enough to compress materials into a rocky core.... More » Science Astronomy Planets

All four of the gas giant planets in the solar system have rings. These are Saturn, Jupiter, Neptune and Uranus. The rings of Saturn are so prominent that they can be seen with binoculars on clear nights. The rings of th... More »

Saturn is the fifth-brightest item in the solar system, and unlike most other planets, it is visible to the naked eye. Whereas it takes one year for Earth to complete an orbit around the sun, Saturn moves much more slowl... More »