The smell of freshly cut grass is actually a plant distress call.
31
Your brain is 80% water.
525
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
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
It takes a photon 170,000 years to travel from the core of the Sun to the surface, but only 8 minutes to travel the rest of the way to Earth.
6
Sound travels fifteen times faster through steel than through air.
134