Stephen Hawking once tried to find potential time travellers by throwing a party and only sending out invitations after the party.
17
When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
Because heat expands the metal, the Eiffel Tower always leans away from the sun.
79
Sound travels fifteen times faster through steel than through air.
134
The gas that gives rotten eggs their distinctive foul smell may slow ageing and block damaging chemical reactions inside cells, according to scientists in China.
5
Sound travels about 4 times faster in water than in air.
408
Research indicates that plants grow healthier when they are stroked.
173
Every day, plants convert sunlight into energy equivalent to six times the entire power consumption of human civilization.
9