Optical illusions occur when what the eyes see conflicts with what the brain expects.
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
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
At room temperature, the average air molecule travels at the speed of a rifle bullet.
55
Sound travels about 4 times faster in water than in air.
408
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
Each day is longer than the previous on by 0.00000002 seconds which is 13 seconds each century!
116
One third of the electricity produced on earth is used to power electric light bulbs!
75