It’s All About Scale
“A single speck of dust is half way in size between an atom and the Earth.”
This statement has been going around the internet recently and I felt compelled to check it out.
Guess what? It’s true – basically.
To be closer to the truth, you’d have to say “A single speck of dust is half way in size between a subatomic particle and the Earth.”
So as large as Earth appears compared with a speck of dust, the dust is that much larger than a subatomic particle.
That’s pretty amazing. But, let’s pull it apart and take a better good look.
A subatomic particle is smaller than an atom and atoms are pretty darned small.
What subatomic particles are we thinking of?
If we’re thinking of a quark, that’s a particle that the protons and neutrons in the center of an atom are made of, then the statement would more accurately be:
A single speck of dust is half way in size between a quark and the planet Jupiter.
If we’re thinking neutrino, a tiny, tiny particle that results from radioactive decay, cosmic radiation or the fusion reactions inside the Sun, then the statement would more accurately be:
A single speck of dust is half way in size between a neutrino and the diameter of the solar system.
Really.
The next time you see a speck of dust lazily floating in the air….think about how huge it is compared to an atom.
It just blows my mind.
If you enjoy science, follow me on Twitter @Science_186000
Filed under: Science | 5 Comments
Tags: dust, neutrino, quark, subatomic particle
Random Thoughts From Shipguy 
I need some help here! Seriously. I need to know the relative “size” of a gas molecule (any gas, just an approximation) and a dust particle (say 5 microns). Is it, say like a dust particle to a bowling ball? A dust particle to the moon? Do I have to figure this out myself?!
I find that hard to believe. Not in linear terms, at least. Logarithmically, yes. But linearly, if a speck of dust is halfway there, I imagine that all the way there is two specks of dust. Not quite the same thing.
I think what he is saying is that if you divide the diameter of the earth by the diameter of the proton/neutron union and get a value of 2X then divide the diameter of the earth by the diameter of a dust mote you would get 1X. So the Dust speck is half way in there. The proton/neutron pair are very very tiny!
Both a neutrino and a quark have size 0, they are point-like for all we know. So your statement does not make sense. Maybe you are talking about mass and not size?