Nevertheless, it is possible to see them. To do this, scientists use electronic microscope which has a fine needle with a tip that is made up of a single atom. The surface of atoms under observation is scanned with this sharply pointed tip which, being atom, has electrons in various orbits. Likewise, atoms it surveys also have electrons around the nucleus. As is well-known, electrons are negatively charged, prone to mutual repulsion. Therefore, if the needle is directly above an atom, both the electron sheaths repel one another. The needle stays at a higher level. In the space between two atoms, however, it can penetrate deeper into the object before it moves on to the next atom. Many atoms are sized up in this manner and based on it, a visual image is created.