Stephen Hawking once tried to find potential time travellers by throwing a party and only sending out invitations after the party.
17
0.3% of solar energy from the Sahara is enough to power the whole of Europe.
310
Airports that are at higher altitudes require a longer airstrip due to lower air density.
39
During photosynthesis, plants emit light humans can’t see, but NASA can see that light from space - and they've even made maps of it!
21
Rafflesia Arnoldii is the largest flower in the world and can grow as big as an umbrella.
42
Cold water weighs more than hot water.
93