Superman (1939). Certain materials such as lead can block his X-ray vision. Superman can project beams of heat from his eyes which are hot enough to melt steel. He first used this power in "Superman" #59 (1949) by applying his X-ray vision at its highest intensity. In later stories, this ability is simply called "heat vision". Superman can hear sounds that are too faint for a human to hear, and at frequencies outside the human hearing range. This ability is introduced in "Action Comics" #11 (1939). "Action Comics" #1 (1938) explained that Superman's strength was common to all Kryptonians because they
Origin of Superman time in "Superman" #61. "Action Comics" #158 retold the origin again, this time acknowledging the adventures of Superboy. After Mort Weisinger took over as editor of the Superboy comics in 1953, the mythology of Superman began growing, starting with the introduction of Superboy's pet Krypto the Superdog, the first survivor of Krypton in comics other than Kal-El himself. When Weisinger became editor of the entire Superman line in 1958, the Superman mythology began expanding even more rapidly. Producing over a hundred Superman stories a year, Weisinger aimed to introduce a new element to the character's mythology every six months. By