Atoms are really, really small. I’m going to tell a story to try and help us visualise the scale they’re at.
The world’s most classic road trip has to be the coast to coast drive in the USA. It’s the trip made famous by the novelist Jack Kerouac and his Beat Generation of the late 1940’s. Countless travellers have followed in his footsteps since by renting an old car, and driving the four to five-day journey across the heart of the American continent.
All experiences are different, but one thing that every person comes away with is a perspective for how prodigious size of the country. Jack Kerouac writes in his novel about the experience:
”All that raw land that rolls in one unbelievable huge bulge over to the West Coast, and all that road going, all the people dreaming in the immensity of it.Jack KerouacOn The Road
Imagine that midway on that long journey, Jack pulled over somewhere on Highway 80 to stretch his legs. As he opened his car door and stepped out, a loose quarter fell from the car and clattered onto the roadside unnoticed, shining in the sun. After a few stretches and a cigarette, he was off again to continue his journey.
Now let’s jump perspectives.
Twenty years later, another journey is taking place. This time it’s Buzz Aldrin, and he’s on his way to the moon. He looks out the window of Apollo 11 and down at the blue Earth below. He’s far enough out such that he can see the whole United States at once, the entire continent that took Jack five days to drive across.
Let’s pretend that he knows about Jack Kerouac’s lost quarter on the ground. He’s also done a bit of maths and has worked out the approximate size of an atom.
Buzz takes out his own quarter and holds it up against the United States, blotting it out from coast to coast.
From Buzz’s perspective (and if he had incredibly good eyesight), Jack’s quarter all the way down on the ground in the middle of the USA below, and the atoms in his own quarter, would be the same size.
That is how big an atom is.
What is really fun is that atoms, tiny as they are, are made of particles. The atom’s nucleus is made of protons and neutrons that are over 10,000 times smaller again!