How much is a billion?

Last week I was in New Mexico visiting an area that is known to have “dark sky”.  The exact location was Chaco Canyon, a National Historical Park, northwest of Albuquerque.  Dark sky refers to a night sky where the stars do not have competition from city and town lights at night.  There are fewer and fewer black sky areas in the United States.  If you haven’t been to one lately, I suggest you take your family and visit one soon.  Seeing the Milky Way as a real splash of billions of white stars across the sky is a marvelous experience.

The sky in Chaco Canyon before the sun was completely set.

Whether describing the vastness of the stars or the microscopic intricacies of the human body, the need to use large numbers is often inevitable. When we consider the estimated 200,000,000,000 (200 billion) stars in the Milky Way Galaxy or the estimated 150,000,000,000 (150 billion) galaxies in the universe or the estimated 100,000,000,000,000 (100 trillion) cells in the adult human body, we are forced to use numbers so large we cannot comprehend their meaning. Here is a way to imagine these large numbers and to place some them in perspective.

Money Stacks

One way to better understand large numbers is to compare the heights of stacks of varying numbers of dollar bills. The thickness of a single one dollar bills measures .0043 inches or .0000000679 miles.

The height of a stack of 100 one dollar bills measures .43 inches.

The height of a stack of 1,000 one dollar bills measures 4.3 inches.

When your child asks “how much is a million?”

It is the height of a stack of 1,000,000 one dollar bills measures 4,300 inches or 358 feet – about the height of a 30 to 35 story building.

The height of a stack of 100,000,000 (one hundred million) one dollar bills measures 35,851 feet or 6.79 miles. This would reach from the earth’s surface to the approximate altitude at which commercial jetliners fly.

How much is a billion?

It is the height of a stack of 1,000,000,000 (one billion) one dollar bills measures 358,510 feet or 67.9 miles. This would reach from the earth’s surface into the lower portion of the troposphere – one of the major outer layers of earth’s atmosphere.

What about a trillion?  How many is that?
The height of a stack of 1,000,000,000,000 (one trillion) one dollar bills measures 67,866 miles. This would reach more than one fourth the way from the earth to the moon.

The height of a stack of 100,000,000,000,000 (one hundred trillion) one dollar bills measures 6,786,616 miles. This would reach from the earth to the moon and back 14 times.

I would love to know if this is true – has anyone tried stacking this many bills?

The Milky Way