The Earth's atmosphere weighs about 5.5 quadrillion tons.
108
A single speck of dust is half way in size between a subatomic particle and the Earth.
15
When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
One 75-watt bulb gives more light than three 25-watt bulbs.
57
The Manchineel Tree is so poisonous, rainwater dripping off it’s leaves will burn your skin.
17
Stephen Hawking once tried to find potential time travellers by throwing a party and only sending out invitations after the party.
17
Approximately 70 percent of the earth is covered by water. Only 1 percent of this water is drinkable.
65