The Earth's atmosphere weighs about 5.5 quadrillion tons.
108
A cesium atom in an atomic clock beats over nine billion times a second.
43
Optical illusions occur when what the eyes see conflicts with what the brain expects.
75
If the chemical sodium is dropped into water it will immediately and violently explode.
67
0.3% of solar energy from the Sahara is enough to power the whole of Europe.
310
There are more than 270 people cryogenically frozen in the hope that one day the technology will exist that can revive them and extend their lives.
13
4.5 pounds of sunlight strike the Earth each day.
27
Billions of neutrinos pass unnoticed through your body every second.
6