Optical illusions occur when what the eyes see conflicts with what the brain expects.
75
When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
Galalith is a type of plastic that can be made from milk. It is odourless, insoluble in water, biodegradable, anti-allergenic, antistatic, and virtually non-flammable.
1
For every gallon of sea water, you get more than a quarter pound of salt.
45
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
MIT has developed a camera that captures the speed of light at a trillion frames per second.
20
In Arizona, a solar wind energy tower has been proposed that would generate as much energy as the Hoover Dam.
5