Stephen Hawking once tried to find potential time travellers by throwing a party and only sending out invitations after the party.
17
Iron weighs more after it rusts.
16
Nuclear power prevented an average of over 1.8 million deaths between 1971-2009 as a result of lower air pollution from reduced coal usage according to NASA.
5
The smell of freshly cut grass is actually a plant distress call.
31
A single speck of dust is half way in size between a subatomic particle and the Earth.
15
Out of all the senses, smell is most closely linked to memory.
146
Pumice is the only rock that floats on water.
14
0.3% of solar energy from the Sahara is enough to power the whole of Europe.
310