Nucleon is the name given to particles within the nucleus of an atom (i.e. protons and neutrons). The 247th element, discovered by the crew of the USS Voyager in the ring of a gas giant in the Delta Quadrant, is a stable element with an unusually large atomic mass and over 550 nucleons. (VOY: "Emanations") In the script of the Star Trek: Deep Space Nine pilot episode "Emissary" , Chief O'Brien mentions that stray nucleonic emissions needed to be found aboard Deep Space 9 before the transporter systems could be used.