How Big Is an Atom?

Atoms are certainly not big. They are so small that until recently they couldn’t even be seen with the world’s most powerful microscope.

An atom is so small that it is almost impossible to understand how small a single atom is. It is easier to think about how long a line of 1 million atoms might be. Take a page of a book and hold it between your thumb and forefinger so that you get an idea of how thick the paper is.

One million atoms lined up in a row would roughly equal the thickness of the page you are holding. Even the finest of optical microscopes cannot see an atom.

Only electron microscopes, which “see” with electricity and make a picture like the one you have on your TV set, are powerful enough to magnify an atom so it can be seen.