Cows can sleep standing up, but they can only dream lying down.
745
Mars had an oxygen-rich atmosphere around 4 billion years ago
13
No one knows Albert Einstein's last words. Just before he passed, he spoke several words in German, but his nurse only knew English.
154
In Georgia, there is an airtight room called the Crypt of Civilization that was sealed in 1940. It contains numerous artefacts documenting what life was like at the time of sealing, and is scheduled to be opened in the year 8113 to show people of the future exactly what life was like.
13
In 2011, archaeologists discovered the skeletal remains of a Roman couple who have been holding hands for 1,500 years.
81
A lump of pure gold the size of a matchbox can be flattened into a sheet the size of a tennis court.
140
An unprotected human can survive up to 1.5 minutes in space with no permanent bodily damage.
82