Career
He started observing in the 1930s. After the Second World War he founded the Association of Lunar and Planetary Observers (ALPO) and served there as the executive director between 1947 and the mid-1980s.
He started observing in the 1930s. After the Second World War he founded the Association of Lunar and Planetary Observers (ALPO) and served there as the executive director between 1947 and the mid-1980s.
Since then he had been a member of the board of directors as the Director Emeritus.