Stephen Hawking once tried to find potential time travellers by throwing a party and only sending out invitations after the party.
17
Cold water weighs more than hot water.
93
When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
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
In Arizona, a solar wind energy tower has been proposed that would generate as much energy as the Hoover Dam.
5
In the 1950s, the US government placed beer next to an atomic bomb blast to determine if it was still drinkable. The result: in the event of a nuclear war, beer is safe to drink!
16
Approximately 70 percent of the earth is covered by water. Only 1 percent of this water is drinkable.
65