Mars had an oxygen-rich atmosphere around 4 billion years ago
13
A lump of pure gold the size of a matchbox can be flattened into a sheet the size of a tennis court.
140
A cow produces around 200,000 glasses of milk in her lifetime.
373
Scientists have revived a flowering plant from a fruit stored away in permafrost by Arctic ground squirrel 32,000 years ago.
16
You forget 90% of your dreams.
256
Cows can sleep standing up, but they can only dream lying down.
745