The age of our universe is about 15 billion years. That’s a number so big that it is difficult to make sense of. You might as well say that it’s 2 trillion years. (Some strongly insist that the universe is only about 6,000 years old, but we’ll discuss that one in another post.)
To help us make sense of this immense span of time and how much of our own history occupies it, world renown astronomer Carl Sagan popularized a tool to see it from a human perspective. He scales our universe’s 15 billion year history into one year. Each month represents just over one billion years. The big bang occurs at midnight on January 1, and our present moment is represented by the last second of the last minute of December 31. See Carl Sagan here explaining the cosmic calendar and the surprising reality that we are but a tiny speck in the thirty-first square.
Additionally, at this page entitled The Cosmic Timeline you’ll find more information and several excellent graphic representations of our cosmic history.
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January 29th, 2008 at 3:14 pm
I always liked the analogy of the amount of time since the earth formed to now using your armspan. If that is our measuring stick, then all of human history is contained in the amount you would file off with a nail file at the end of your fingernail. Wacky!
Here is a more detailed version:
http://jersey.uoregon.edu/~mstrick/AskGeoMan/geoQuerry16.html