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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Seal a cat inside a box with a radioactive atom, a radiation detector and a mechanism capable of releasing poison. Arrange the experiment so that, after an hour, the atom has a 50 percent ch...
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You may already have yawned simply because you read the word. If not, there is a reasonable chance that a photograph or video of someone opening their mouth in a long yawn would do the job....
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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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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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When Iñupiat hunters and biologists began finding ancient weapon fragments inside bowhead whales harvested in Arctic Alaska, the discoveries posed an extraordinary question: how long had the...
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On October 30, 1961, a Soviet Tu-95 bomber crossed the frozen landscape of Novaya Zemlya carrying an object so large that the aircraft had been specially modified to accommodate it. The bomb...
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An old tree can carry the shape of an injury long after the branch that caused it has disappeared. A swollen collar may surround the site of a lost limb. Growth rings can bend around the old...
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