In this composite image, the sun has reached its northernmost point in Earth's sky, marking a season change and the first solstice of the year 2004. NASA/ESA hide caption

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Do You Really Know Why Earth Has A Solstice?

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The Milky Way fills the night sky over Chile's Cerro Paranal, home to the European Southern Observatory's Very Large Telescope (VLT). Y.Beletsky/ESO hide caption

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