Consider that the nucleus of an atom can hold all kinds of electrons in moonlike orbit. Yet the nucleus is so tiny we cannot even see it.
“Consider that the nucleus of an atom can hold all kinds of electrons in moonlike orbit.”
It doesn’t hold them in orbit with gravity though, that is electromagnetism.
Possibly manifestations of the same basic force, but we haven’t established that connection yet.
So, atoms are held together by gravity?
You are mistaking gravity with electromagnetic force.
http://www.answers.com/Q/What_force_holds_the_electrons_around_the_nucleus_of_an_atom
fascinating