0.3% of solar energy from the Sahara is enough to power the whole of Europe.
310
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
Pure water (H2O) does not conduct electricity on its own.
46
Stannous fluoride, which is the cavity fighter found in toothpaste is made from recycled tin.
65
Iron weighs more after it rusts.
68
When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
One barrel of petroleum holds 42 gallons.
20