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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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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Pumice is the only rock that floats on water.
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Iron weighs more after it rusts.
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One 75-watt bulb gives more light than three 25-watt bulbs.
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Stephen Hawking once tried to find potential time travellers by throwing a party and only sending out invitations after the party.
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Brass doorknobs automatically disinfect themselves in about 8 hours.
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Forensic scientists can determine a person's sex, age, and race by examining a single strand of hair.
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