The lifespan of a red blood cell is around 120 days.

Red blood cells are formed in the red bone marrow of bones.

Hydrogen contains one proton and three neutrons in its nucleus.

It is a highly unstable isotope of hydrogen.

Venus travels around the sun once every 225 Earth days but it rotates clockwise once every 243 days.

The Pascaline was designed and built by the French mathematician-philosopher Blaise Pascal between 1642 and 1644.

The structure of the earth is divided into four major components: the crust, the mantle, the outer core, and the inner core.