earth

Earth

The Earth is one of the nine planets. Earth is the third planet from the Sun and is the fifth largest planet. All of the other planets’ names came from Greek and Roman mythology, except for Earth. Earth is the oldest planet. Earth has only one moon, which is 384,400 km from Earth.
Earth is about 4.5 to 4.6 billion years old. The Earth has many layers. The innermost layer is the core, followed progressively by the upper mantle, lower mantle, transition region, D'' layer, outer core and the inner core. The layers have specific chemicals that are caused by earthquakes’ vibrations. The crust is 0-40 km deep, the upper mant...