Earth

The Earth, which is located three planets from the Sun, is the only planet in the universe known to support any kind of life. The Earth is estimated to be approximately 4.57 billion years old. The moon followed not long after. The Earth rotates around its own north to south axis once every 23 hours, 56 minutes and 4.091 seconds (one day), and around the Sun once every 365.2564 days (one year).
The Earth formed when the initial molten lava mass cooled and formed a solid outer crust. The Earth’s approximation to the Sun and ability to absorb its solar energy allowed for photosynthesis to occur. This began the accumulation and storage of oxygen in the Earth’s atmosphere and the development of what we now know as the ozone layer. Early eukaryotic life on Earth soon followed.
With the complete formation of the ozone layer, which blocked all harmful ultraviolet radiation from the Sun, multicellular life began to slowly populate the planet. Following several major catastrophic life extinctions, mankind’s first ancestors slowly began to evolve, beginning the early stages of what has lead to the world as we know it today.
For more information about the evolution of planet Earth, including various Earth science topics, simply click on any link or interactive feature on the page below. You may also view a number of incredible images of Earth, and even a satellite image of Earth taken from space!