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
Superman beyond the comic books. Superman, Inc. merged with DC Comics in October 1946. After DC Comics merged with Warner Communications in 1967, licensing for Superman was handled by the Licensing Corporation of America. The Licensing Letter (an American market research firm) estimated that Superman licensed merchandise made $722 million in sales globally in 2017. 44.7% of this revenue came from the North American market. For comparison, in the same year, Spider-Man merchandise made $1.4 billion and Star Wars merchandise made $2.4 billion globally. The earliest paraphernalia appeared in 1939: a button proclaiming membership in the Supermen of America club. The