A fish can be surrounded by water and still run out of oxygen. That sounds like a contradiction only because we tend to think of water itself as the thing fish breathe. It is not. Most fish depend on oxygen gas dissolved in water, extractin...
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Ask whether snakes have legs and the obvious answer seems to be no. A cobra, viper or grass snake has no arms, no feet and no visible limbs at all. Yet the evolutionary answer is more intere...
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Put a glass of water near a cat and it may drink calmly. Turn on a faucet and the same cat might become fascinated, batting at droplets for minutes. Lower it into a bathtub, however, and you...
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Space is famously cold. The number repeated in textbooks, documentaries and trivia lists is about 2.7 kelvin, or roughly −270.4 °C — less than three degrees above absolute zero.That number i...
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Ask a child to draw the Sun and there is a good chance they will reach for a yellow crayon. Search for a Sun emoji and you will find the same convention. For centuries, artists have painted...
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On November 20, 1969, Apollo 12 astronauts Pete Conrad and Alan Bean left the lunar surface and rejoined Richard Gordon in orbit. Their lunar module's ascent stage was no longer useful, so m...
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Look up from a truly dark place and the Milky Way appears as a pale river of light crossing the sky. That glow is produced by stars so numerous and distant that most cannot be distinguished...
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Imagine falling feet-first toward a black hole. At first, if the black hole were isolated and you began far enough away, the experience would not feel supernatural. You would be in free fall...
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The internet contains billions of websites, streams enormous quantities of video, connects data centers across continents and crosses oceans through cables thousands of kilometers long. So i...
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The little hat-and-glasses icon has become shorthand for secrecy. Open an Incognito window in Chrome — or a Private Browsing window in another browser — and it feels as though you have stepp...
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