During photosynthesis, plants emit light humans can’t see, but NASA can see that light from space - and they've even made maps of it!
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The weight of a carat (200 milligrams), standard unit of measurement for gemstones, is based on the weight of the carob seed.
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Pumice is the only rock that floats on water.
14
Nylon is made from coal and petroleum.
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A coal power station puts 100 times more radiation into the air than a nuclear power plant producing the same amount of energy.
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Stannous fluoride, which is the cavity fighter found in toothpaste is made from recycled tin.
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Out of all the senses, smell is most closely linked to memory.
146
In Arizona, a solar wind energy tower has been proposed that would generate as much energy as the Hoover Dam.
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