Answer
The $100 Australian banknote featured Sir Douglas Mawson, an Antarctic explorer and geologist. Mawson led several expeditions to Antarctica, including the Australasian Antarctic Expedition (1911-1914) and the British Australian New Zealand Antarctic Research Expedition (1929-1931). His contributions to Antarctic exploration and research earned him recognition and a place on the $100 banknote, which circulated from 1984 to 1996.