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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For 73 years, the Titanic existed in two places at once: in history, where the details of its final night were argued over in inquiries, newspapers and survivor testimony, and somewhere in t...
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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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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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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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Space is a vacuum, so an astronaut cannot simply lift a visor and take a sniff. Yet crews returning from spacewalks have repeatedly described something remarkably close to a smell of space:...
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For generations, chemistry books could place bismuth near the end of the periodic table's stable territory. Its naturally occurring isotope, bismuth-209, showed no detectable radioactive dec...
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