Description This diagram illustrates the Moon's phases in relation to its distance from the Sun. The Earth at center is surrounded by three concentric rings. Along the inner ring are seven discs showing the phases of the waxing and waning moon, indicated by pale yellow wash emanating from the Sun, at right. As the diagram makes clear, and as medieval authorities recognized, the Moon's phases are determined by the extent of its illumination by the Sun. The cycle begins with the new, crescent Moon at upper right (approximately 2 o'clock) and moves counterclockwise, with the days of the lunar cycle given in red. It ends when the Moon is not visible -- that is, when it lies directly between the Earth and Sun, the latter labeled "Sol XXX."
Provenance Gruel and Englemann Collection, Paris ; acquired by Henry Walters, Baltimore, 1903; by bequest to Walters Art Museum, 1931.  no. 131, bookplate on inside upper board
Credit Acquired by Henry Walters, 1903
Download Image Add to Collection Share on Twitter Share on Facebook Creative Commons License