· The eight planets have been divided into two groups. All the planets of a particular group have some common features; ‘terrestrial planets’ or ‘rocky planets and ‘’Jovian planets’ or ‘gaseous planets’ (gas giants) are the two groups of planets.
· The four planets nearest to the sun –mercury, Venus, earth and mars are called terrestrial planets, because their structure is similar to the earth.
· Other four planets – Jupiter, Saturn, Uranus and Neptune are allied Jovian planets.
· Planets are classified into the following two groups inner and outer planets. These are separated by asteroid belt:
INNER PLANETS
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OUTER PLANETS
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They include mercury, Venus, earth,
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They include Jupiter, Saturn, and Uranus Neptune etc.
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They are nearest to the sun.
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They are far away from the sun.
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They are made up of dense metallic minerals.
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They are made up of hot gases, mainly hydrogen and helium.
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They move faster and have a shorter
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They move rather slowly and have a longer period of revolution.
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They have thin, rocky crust.
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They are all gaseous bodies.
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They have a mantle rich in iron and magnesium.
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Made of gases.
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They have a core of molten metals
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They have ring systems around them
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They have thin atmosphere
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They have very few natural satellites (of moons() or no satellites.
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They have a large numbers of natural satellites (or moons).
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