Optical illusions occur when what the eyes see conflicts with what the brain expects.
75
The only letter not appearing on the Periodic Table is the letter "J".
180
Only 12,000 years ago there was a species closely related to modern humans called Homo floresiensis that had been living on an Indonesian Island. They used fire and rather advanced tools, yet were only about 3 feet tall and weighed around 25kg.
15
If the chemical sodium is dropped into water it will immediately and violently explode.
67
A single speck of dust is half way in size between a subatomic particle and the Earth.
15
Research indicates that plants grow healthier when they are stroked.
173
Sound at the right vibration can bore holes through a solid object.
134
At room temperature, the average air molecule travels at the speed of a rifle bullet.
55