Question

On what days do we have equal days and nights all over the world?
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Answer 1

Answer:

On 21 March and 23 September, the Sun shines vertically on the Equator; therefore, all places on the Earth experience equal days and equal nights. On 21 March, the Northern Hemisphere has spring, while the Southern Hemisphere has autumn. On 23 September, the Northern Hemisphere has autumn, while the Southern Hemisphere has spring.

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