500 Yen - Heisei Antarctica

Issued to mark the 50th anniversary of Japan's participation in the International Geophysical Year (1957–58), which established the Showa Station on East Ongul Island in Antarctica — a base that has operated continuously, with only a brief interruption in the early 1960s, ever since. Japan was one of twelve nations conducting coordinated geophysical research during that program, and the Antarctic research mission became a point of considerable national prestige during the postwar recovery period.