Krypton, for one, is a GAS, PLANET, ELEMENT, raregas, inertgas, and noblegas. It is a chemical ELEMENT with the symbol Kr and atomic number 36. It is a colorless, odorless, tasteless noble GAS that occurs in trace amounts in the atmosphere and is often used with other rare gases in fluorescent lamps. Krypton is also the name of a fictional PLANET in the DC Comics universe, home to Superman. Krypton is also the name of a fictional PLANET in the Star Wars universe, home to the Sith species.