Gas giant

A gas giant is a planet that does not have a hard surface like the Earth or the Moon. It just consists of the gas form of chemicals such as Hydrogen, Methane or Ammonia. When there is not enough, or too little gas, the gas just forms a cloud which is also called a Nebula - but when there is just enough gas, it forms into a planet. However, because gas is not very dense, these planets are always very large - hundreds of times as big as the Earth.

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