Lunar crater 'Gassendi', 1840-1860

Lunar crater 'Gassendi', 1840-1860. Pastel sketch (obverse), undated, by James Nasmyth (1808-1890) in crayon of the lunar crater, 'Gassendi'. Working directly from the eyepiece of his 20 inch reflecting telescope, he used his considerable artistic skill to produce this portrayal of the lunar surface. Nasmyth a successful industrialist and engineer made extensive observations of the Moon. Using his drawings he calculated the height of the lunar features by measuring the length of their shadows. He then made relief models that were photographed to produce results better than could be then achieved using direct lunar photography. Nasmyth photographed a series of these models, which were used to illustrate the book, 'The Moon' that he co-published with James Carpenter in 1871. ©SSPL/Science Museum