Mars had an oxygen-rich atmosphere around 4 billion years ago
13
If you have 1 billion dollars and spend $1,000 every day, it would take you 2,740 years to go broke.
31
A lump of pure gold the size of a matchbox can be flattened into a sheet the size of a tennis court.
140
In 2011, archaeologists discovered the skeletal remains of a Roman couple who have been holding hands for 1,500 years.
81
Your thumb is about the same size as your nose.
124