Mars had an oxygen-rich atmosphere around 4 billion years ago
13
It's possible to die from a broken heart; it's called Stress Cardiomyopathy.
165
An unprotected human can survive up to 1.5 minutes in space with no permanent bodily damage.
82
Cows can sleep standing up, but they can only dream lying down.
745
You forget 90% of your dreams.
256
The University of Oxford (teaching since 1096) predates the Aztec empire (1428 - 1521).
14
Your body is creating and killing about 2.4 million red blood cells per second.
17