Pumice is the only rock that floats on water.
14
When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
The sun is 330,330 times larger than the earth.
75
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
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
Scientists are now able to grow 'beating' heart tissue in a lab!
162
The brain case [of Neanderthals] on the average was more than 13 percent larger than that of the average of modern man
61