Though you may not have noticed, today is the 2050th anniversary of Julius Caesar's assassination.
Most of us have a vague sense of what happened that day. Caesar was, of course, a great conqueror. He was very popular with the ordinary folks in Rome, but not so popular with a small group of senators who feared that at any moment he would make himself an absolute dictator.
The senators, including his friend Brutus ("Et tu?"), conspired, invited him to the Senate, gathered round and stabbed him over and over. Caesar, mortally wounded, exhaled and died.
And it's not like Caesar hadn't been warned. Soothsayers had told him to "Beware the Ides Of March" -- "ides" meaning the middle of the month. But he paid no heed.
That's what most people know.
The Chemistry Angle
Here's what chemistry students know: For some reason, Caesar's dying breath, his last exhalation, has become a classic teaching tool in high school and college. When Caesar exhaled, he released an enormous number of "breath" molecules, mostly nitrogen and carbon dioxide. It's a very, very big number says Dan Nocera, chemistry professor at the Massachusetts Institute of Technology (MIT). By Nocera's calculation: .05 x 6 x 10 to the 23rd.
"10 to the 23rd" all by itself looks ridiculously large. It's 10 followed by 22 zeros:
Over the years, a number of scholars have tried to figure out what typically would happen to all those molecules. They figured some were absorbed by plants, some by animals, some by water -- and a large portion would float free and spread themselves all around the globe in a pattern so predictable that (this is the fun part) if you take a deep breath right now, at least one of the molecules entering your lungs literally came from Caesar's last breath.
That's what they say.
If you look around the Internet, you will find professors who say we take in three of Caesar's molecules per breath, or eight, or 10. It all depends on your assumptions about the size of a breath, the size of the atmosphere, the location of the breather (on a mountain, or at sea level?)
To Commemorate Caesar's Demise...
But bottom line?
Even though these calculations apply to any breath exhaled long ago -- Shakespeare's, Cleopatra's, Lincoln's, your great-great-grandma's -- you may still want to take a moment today to share with Caesar. Just breathe in and share his molecule.