How do you draw something you have never seen before?  Someone could tell you what it looks like.  But what if no one has ever seen it before?  What if people only know how it acts and that's all they can tell you?  It's as if someone had never seen an elephant before but they knew it had a long and strong nose because the tops of the trees were broken and it had big feet because of the prints in the mud.  Such is the case with atoms, the building blocks of Earth.  Atoms are so small we cannot even see them with a microscope.  All scientists can do is run experiments with different materials and see how they react.  Then they make guesses as to what the atom looks like.  For all of their guesses, the following is the best we could come up with.  So take out your pencil and . . . get ready to draw an atom.


(Note: There are lots of different things to learn about atoms, but today we are just going to try and figure out what they look like.)


There are a few ideas of what an atom looks like, but the easiest to picture is the one that looks like our solar system.  Let's face it, everything, even the smallest building block, has to have a middle, right?  The nucleus is the middle of the atom.  You can think of it like the sun in our galaxy.  It is made up of two different parts that hold each other together, but we are not know sure how that works yet.  Only the best scientists will tell you they do not know something.  In fact, some of them try to be wrong at least six times before breakfast.  Do not start drawing just yet.  I need to tell you what makes up the middle first. 

The nucleus of an atom is huge compared to the electrons like our sun is huge compared to the planets.

The International Astronomical Union/Martin Kornmesser, CC BY 4.0 , via Wikimedia Commons

The sun is not just made of sun stuff, and the nucleus is not just a nucleus.  We can get even smaller than that.  Think of a group of two kinds of small dots inside this middle.  The first are protons, one of the parts that make up the nucleus.  Some atoms have more of them and some atoms have only one.  All of these look the same, so you will not need to draw something different for each one.  Wait, we are talking about one of the smallest things we know, so how small are these parts?  If an atom, which you cannot see, were the size of a football stadium, a proton would be smaller than a marble.  So make the lightest touch you can with the tip of your pencil right in the middle of your picture.  Tap, tap, tap.  Do this a few times.


Neutrons are the other part that makes up a nucleus.  They are just as small as protons.  Each of them are also all the same.  We believe that they are there to help keep everything together.  Most of the time there are just as many neutrons as there are protons.  You might want to get a different colored pencil out for these.  Put them next to and around your first dots.  Remember . . . light taps, tiny dots.  Great.  You have got your nucleus. 

Protons and neutrons could look like this star cluster with a lot fewer stars.

NASA, The Hubble Heritage Team, STScI, AURA, Public domain, via Wikimedia Commons

Now we can leave the center part of our atom behind.  Let's look at the space around the outside.  Electrons are tiny parts that move around the nucleus and can move from atom to atom as electricity.  Because they are what make up electricity, they move around a lot.  Just as the sun pulls in the Earth, the middle of the atom pulls in the electrons and keeps them moving around it.  You get to decide how these little things move around your picture.  What color are you going to use?  You might want to make it a fast color. 

Electrons moving around the nucleus of an atom may look like this,

ESA, NASA, and L. Calcada (ESO for STScI), Public domain, via Wikimedia Commons

It is not easy to draw something you have never seen before.  But that is often the job of a scientist.  We know some things about atoms.  We know that they have a nucleus, a middle, which is made up of neutrons and protons and that these are about the same size.  We also know that it has electrons, or pieces of electricity, moving around it.  So . . . what did you draw?  Does it look like our galaxy?  Does it look silly?  Trust me, it's no more silly than what others have dreamed up.  And who knows?  Your picture could be right.



References:

School For Champions.  "Structure of the Atom"  School For Champions, 2007.  <http://www.school-for-champions.com/science/atom.htm>

Science For Kids.  "Protons"  Science For Kids, 2012.  <http://scienceforkids.kidipede.com/chemistry/atoms/proton.htm>

Science For Kids. "Neutrons" Science For Kids, 2012.  <http://scienceforkids.kidipede.com/chemistry/atoms/neutron.htm>

Science For Kids.  "Electrons"  Science For Kids, 2012.  <http://scienceforkids.kidipede.com/chemistry/atoms/electron.htm>

Ducksters.  "The Atom"  Science For Kids, 2009.  <http://www.ducksters.com/science/the_atom.php>