The strangers in your dreams are actually people that you've seen in real life.
50
Mars had an oxygen-rich atmosphere around 4 billion years ago
13
There is a mass reservoir of water floating in space that is 100,000 times bigger than our sun and holds 140 trillion times more water than all of our oceans.
11
The University of Oxford (teaching since 1096) predates the Aztec empire (1428 - 1521).
14
The oldest stone tools found are dated from 2.7 - 2.9 million years ago. The species that made these tools is unknown.
13
Cows can sleep standing up, but they can only dream lying down.
745
The focusing muscles of the eyes move around 100,000 times a day. To give your leg muscles the same workout, you would need to walk 80km (50 miles) every day.
21