Astronomy › lesson 11 of 100 · Beginner

Planets: Inner vs Outer

Inner planets are rocky, while outer planets are primarily gaseous.

Consider the planet Earth, which we know is a rocky world with a solid surface. This characteristic is shared by other inner planets like Mercury, Venus, and Mars, which are also rocky. In contrast, the outer planets like Jupiter, Saturn, Uranus, and Neptune are mostly composed of gases.

The distinction between inner and outer planets is based on their distance from the Sun and their composition. The inner planets are closer to the Sun and have solid, rocky surfaces, while the outer planets are farther away and are primarily made up of gases like hydrogen and helium.

This difference in composition is due to the conditions under which the planets formed. The inner planets formed in a region close to the Sun where temperatures were too high for gases to condense, resulting in rocky planets. The outer planets, on the other hand, formed in a region where it was cold enough for gases to condense, leading to the formation of gaseous planets.

أمثلة

• MercuryA rocky inner planet
• JupiterA gaseous outer planet
• MarsA rocky inner planet
• SaturnA gaseous outer planet
• VenusA rocky inner planet

تتحقق الدورة الكاملة من كل درس بـ5 أسئلة، وتتكيّف مع مستواك، وتحفظ موضعك.