Cows can sleep standing up, but they can only dream lying down.
745
Your body is creating and killing about 2.4 million red blood cells per second.
17
An unprotected human can survive up to 1.5 minutes in space with no permanent bodily damage.
82
It's possible to die from a broken heart; it's called Stress Cardiomyopathy.
165
There are so many kinds of apples that if you ate a new one everyday, it would take over 20 years to try them all.
34
You forget 90% of your dreams.
256
Mars had an oxygen-rich atmosphere around 4 billion years ago
13