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Astronauts grow about 5 cm taller in space
On Earth, gravity compresses the discs of cartilage between ...
Niagara Falls is slowly moving backwards — about 30 cm per year
Niagara Falls has been eroding the rock beneath it since it ...
Dolphins sleep with one eye open and half their brain at a time
Dolphins cannot breathe automatically like we do — they have...
The Sun loses 4 million tonnes of mass every second — turning it into light and heat
Every second, the Sun converts 4 million tonnes of its own m...
Baby kangaroos are the size of a jellybean when they're born
A newborn kangaroo is called a joey. It is born after just 3...
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