Taste a drop of seawater and the answer seems obvious: the ocean contains salt. The more interesting question is how it got there. There are no gigantic salt deposits steadily dissolving into every sea, and most rivers taste fresh even thou...
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Step out of a dark cinema into brilliant afternoon sunlight and, for some people, the reaction is immediate. The eyes narrow, the nose begins to tingle and within seconds comes an involuntar...
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Imagine exchanging messages with an unseen stranger. The replies are witty, coherent and sensitive to context. The stranger remembers what you said earlier, catches a joke, explains a diffic...
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There is a place on Earth where Mount Everest could be lowered beneath the waves and its summit would still remain underwater. It lies in the western Pacific, in the Mariana Trench, where th...
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Somewhere on Earth, while you read this sentence, babies are being born and people are dying. Others are crossing national borders, changing the population of one country without changing th...
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It is one of those questions that sounds almost too simple to deserve a scientific explanation. Look up on a clear afternoon and the sky is blue. Yet that familiar color is the visible resul...
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Near the heart of the Milky Way lies a cloud with a reputation that sounds invented for a science-fiction cocktail menu. Sagittarius B2 contains alcohol. It also contains ethyl formate, an o...
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Few astronomical discoveries have produced a nickname as irresistible as the “diamond planet.” About 41 light-years away in the constellation Cancer, 55 Cancri e is a super-Earth nearly twic...
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Imagine putting the entire Solar System on a cosmic scale: the eight planets, every known moon, the asteroids, comets, dwarf planets, dust and the enormous Sun. The result would be absurdly...
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At this moment, Earth is moving in several different ways at once. It spins on its axis, circles the Sun at roughly 30 kilometers per second, and accompanies the entire Solar System on a vas...
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