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Planet Earth

Planet Earth A-Z

Atmosphere   The Earth's atmosphere is an “ocean of air” that surrounds the planet. It is made up of a mixture of gases, mainly nitrogen (four-fifths) and oxygen (one-fifth).

Aurora   The display of coloured lights seen in the night skies close to the Earth’s magnetic poles. It occurs when high-energy particles from the Sun are trapped by the Earth’s magnetic field.  

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