We are very used to see diagrams of atoms as being composed by little spheres each one with their own characteristics, such as mass, electrical charge, etc. I have also read and heard in many different scientific divulgation media about the scale of the nucleus’ dimension and the size of the electrons’ orbit. Some authors even compare the size of the nucleus in relation to the size of the atom with an scale analogy as comparing a tennis ball in the center of a football stadium, being the tennis ball the nucleus and the electrons then would move in an orbit at a distance equivalent to the outer walls of the stadium. In other cases we hear about the weight a spoonful of a neutron star material will have on earth (being a “spoonful” a measurement of volume). All this examples and many others give a little hint about we knowing, no just the size of atoms, but also the size neutrons, protons and electrons. Do we really know their size? Are we able to measure it? And if we do know their sizes, do we know their shape?