The focusing muscles of the eyes move around 100,000 times a day. To give your leg muscles the same workout, you would need to walk 80km (50 miles) every day.
21
Your body is creating and killing about 2.4 million red blood cells per second.
17
Mars had an oxygen-rich atmosphere around 4 billion years ago
13
Scientists have revived a flowering plant from a fruit stored away in permafrost by Arctic ground squirrel 32,000 years ago.
16
In 2011, archaeologists discovered the skeletal remains of a Roman couple who have been holding hands for 1,500 years.
81
An unprotected human can survive up to 1.5 minutes in space with no permanent bodily damage.
82