Maunder's study of canals on Mars. Drawings of Mars used in an experiment by the British astronomer Edward Walter Maunder (1851-1928) to show that the

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Maunder's study of canals on Mars. Drawings of Mars used in an experiment by the British astronomer Edward Walter Maunder (1851-1928) to show that the \canals\" observed on Mars were an optical illusion. The results of the experiment were published in 1902 and 1903 in volume 63 of the Monthly Notices of the Royal Astronomical Society. The top image is the drawing Maunder asked his experimental subjects to redraw, with the subjects placed at varying distances from the drawing. The bottom drawing shows the \"canals\" observers had reported seeing on Mars. The results of the experiment can be seen in image V700/337. Maunder concluded that the \"canals\" were an optical illusion."

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Size: 2997px × 5953px
Photo credit: © ROYAL ASTRONOMICAL SOCIETY/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

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