Mars had an oxygen-rich atmosphere around 4 billion years ago
13
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
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
Your thumb is about the same size as your nose.
124
If you have 1 billion dollars and spend $1,000 every day, it would take you 2,740 years to go broke.
31
The oldest stone tools found are dated from 2.7 - 2.9 million years ago. The species that made these tools is unknown.
13