Because heat expands the metal, the Eiffel Tower always leans away from the sun.
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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!
21
Optical illusions occur when what the eyes see conflicts with what the brain expects.
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One cubic foot of gold weighs more than 1,200 pounds!
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Airports that are at higher altitudes require a longer airstrip due to lower air density.
39
Iron weighs more after it rusts.
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Dr.Jonas Salk, the man who came up with the cure for polio, didn’t patent the drug. This made the drug more affordable to the general public, and he lost out an an estimated $7 billion dollars for himself.
41