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
When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
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.
6
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
The bark of an older redwood tree is fireproof.
65
Sound travels about 4 times faster in water than in air.
408
Indoor pollution is 10 times more toxic than outdoor pollution.
62
The earth is approx. 6,588,000,000,000,000,000 tons.
175