Our solar system is believed to be 4.6 billion years old. The solar system has existed for approximately the last third of cosmic history. A scale model may be built to help comprehend these numbers. If the history of the universe were represented by a 3,000 page book (for comparison, Webster's Unabridged New International Dictionary, Second Edition, holds a total of 3,208 pages) then the entire history of the solar system would be represented by the last 920 pages.
Those 920 pages include the formation of the sun and planets, the dawn and rise of life, the great geological ages, and the entire history of the human race:
- The last 60 pages represent time from the Devonian epoch to the present.
