Cows can sleep standing up, but they can only dream lying down.
745
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 strangers in your dreams are actually people that you've seen in real life.
50
Pet dogs and elephants are the only animals that seem to instinctively understand human gesture.
14
Mars had an oxygen-rich atmosphere around 4 billion years ago
13