Superman's birthplace
Else clues• Doomed fictional planet
• Doomed planet of comics
• Fission product
• Gas in fluorescent lamps
• Green planet of the comics
• Inert gaseous element
• Its atomic number is 36
• Jor-El's planet
• Kal-El's birthplace
• Neon cousin
• Superman's home
• A colorless element that is one of the six inert gasses
• Occurs in trace amounts in air