Assuming that's the nucleus of an atom, the answer is "electrons". They are in
"clouds", sort of, around the nucleus of atoms.
An electron is the particle that moves around the nucleus of an atom in specific energy levels or orbitals.
"electrons"
An atom contains protons, neutrons, and electrons, electrons being the one that moves around the nucleus. The other two are in the nucleus.
an electron
Elements do not move around the nucleus since the nucleus is at the core of the element.
The negatively charged subatomic particle that moves around the nucleus is the electron. The proton, along with the neutron, comprises the nucleus.
electrons
Electron(s)
electron
ROFLCOPTER
The electron
The name given to a particular space around the nucleus in which an electron moves is Orbital