Stephen Hawking once tried to find potential time travellers by throwing a party and only sending out invitations after the party.
17
Your brain is 80% water.
525
Optical illusions occur when what the eyes see conflicts with what the brain expects.
75
0.3% of solar energy from the Sahara is enough to power the whole of Europe.
310
Because heat expands the metal, the Eiffel Tower always leans away from the sun.
79
One 75-watt bulb gives more light than three 25-watt bulbs.
57
Scientists at the Zhejiang University in China have developed an ultra-light material known as carbon aerogel.
3
The most expensive material on the planet is antimatter - worth $62.5 trillion per gram.
18