4 January 2008

How Much is a Billion ???

Posted by Dan Satterfield

On my Quick Science report the weekend of January 5th I talked about the meaning of one Billion.

Science has in the past used a different definition than the rest of the U.S.

In Europe and much of the rest of the world, the definition varies between countries.

In science, it is very important that mathematical terms have the same definition for all scientist and there the definition used in science journals used to be as follows:

1 Billion= one million millions.

Your Congressman uses a different definition when spending your money… he uses:

1 Billion= 1,000 millions.

You can read more about it here:


So which is right? It depends. If you’re a Congressman, then the usual U.S. definition is right.

If you’re a scientist, then itis important that fellow scientists understand what you mean so many times what we call 4.5 Billion is written as 4,500 million. That way no one gets confused. Science in general is rapidly adopting the new version however and eventually the original definition will be a quirk of history!

I think the original definition is better at stating the value of the number. So the Earth is 4,500 million years old.

Think of it this way, the Earth has celebrated its millionth birthday, 4,500 times. (and as usual I didn’t get invited to the party!)

So keep in mind that if you ask someone in Latin America to write our 1 Billion numerically they may write:

1,000,000,000,000. (We call this a trillion!)
Whereas a high school student here in the States would write:
1,000,000,000 (We call this a billion, but other places call it one thousand million!)

Now, if I were a student and knew this, I could play some nice head games with my science teacher!