Owls can turn their heads about three-quarters of the way around.

Snails have thousands of tiny teeth on their tongues.

Mars has two tiny moons named Phobos and Deimos.

Your heart is about the size of your fist.

Some trees can live for thousands of years.

Earth's inner core is about as hot as the surface of the Sun.

The first bicycle, made in the 1800s, had no pedals — riders pushed with their feet.