Scientists are learning from the 1700-year-old Lycurgus Cup, which changes colour thanks to nano particles.
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Brass doorknobs automatically disinfect themselves in about 8 hours.
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One barrel of petroleum holds 42 gallons.
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In zero gravity, a candle's flame is round and blue.
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Pumice is the only rock that floats on water.
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A cesium atom in an atomic clock beats over nine billion times a second.
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The most expensive material on the planet is antimatter - worth $62.5 trillion per gram.
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It takes a photon 170,000 years to travel from the core of the Sun to the surface, but only 8 minutes to travel the rest of the way to Earth.
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