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
For every gallon of sea water, you get more than a quarter pound of salt.
45
Because heat expands the metal, the Eiffel Tower always leans away from the sun.
79
A cubic yard of air weighs about 2 pounds at sea level.
31
Iron weighs more after it rusts.
16
There are more atoms in one teaspoon of water than there are teaspoons of water in the Atlantic Ocean.
13
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