Stephen Hawking once tried to find potential time travellers by throwing a party and only sending out invitations after the party.
17
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
Indoor pollution is 10 times more toxic than outdoor pollution.
62
Brass doorknobs automatically disinfect themselves in about 8 hours.
18
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
The sun is 330,330 times larger than the earth.
75
Sound at the right vibration can bore holes through a solid object.
134
Pumice is the only rock that floats on water.
14