The planets in Earth's solar system are composed of various forms of matter, primarily categorized into two groups: terrestrial (rocky) planets and gas giants.
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Terrestrial Planets (Mercury, Venus, Earth, Mars):
- Rocky Materials: These planets are primarily composed of silicate rocks and metals.
- Core Components: They typically have a metallic core (iron and nickel) surrounded by a silicate mantle and crust.
- Atmospheric Gases: The atmospheres of these planets vary and may include gases such as carbon dioxide, nitrogen, oxygen, and others, depending on the planet.
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Gas Giants (Jupiter, Saturn):
- Hydrogen and Helium: These planets are predominantly composed of hydrogen and helium gas.
- Hydrogen Compounds: They contain significant amounts of water, ammonia, and methane in their atmosphere.
- Metallic Hydrogen: In the very high-pressure interiors of these gas giants, hydrogen may exist in a metallic state.
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Ice Giants (Uranus, Neptune):
- Ices and Gases: These planets are composed of heavier volatile substances, often referred to as “ices,” including water, ammonia, and methane, alongside hydrogen and helium.
- Rocky Core: Like gas giants, they also have a rocky core but are less massive and have a higher proportion of these ices in their composition.
Overall, the planets in the solar system contain a mix of rocky material, metals, ices, and gases depending on their classification and distance from the Sun.