How Old is Old

I thought this was interesting:

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.

 -At 30 pages from the end, the Age of Dinosaurs comes into full swing.

 - And at 13 pages from the end, the Age of Dinosaurs concludes and the Age of Mammals begins.

 - At 100 words from the end of the book, the Great Ice Age begins.

 - Written human history began less than 10,000 years ago and would occupy no more than the last 1/500th of the last page of the 3,000 page book.

 If an average of 500 words per page is assumed then the entire book would contain 1,500,000 (1.5 million) words. Each word would represent 10,000 years of cosmic history. The last word of the last page would represent all of recorded human history.