This plate is from a deluxe 12-volume atlas of the moon created by astronomers Maurice Loewy and Pierre Henri Puiseaux. The atlas remained the most accurate reference of the moon’s surface until the age of space travel. The duo captured thousands of images at the Paris Observatory through a telescope that Loewy invented. It was equipped with a mechanism that tracked the moon’s movements during the exposures. Given weather conditions, they were only able to photograph 50 to 60 nights per year; the project thus took 15 years to complete and contained nearly 100 large-scale photogravures.