A selection of photographs by astronomer George Willis Ritchey (1864-1945) are among the highlights of Bonhams' History of Science sale on October 22.
The collection, valued at $450,000-550,000, contains over 1,000 images by the man considered the father of astronomical photography.
Starting out as a carpenter, Ritchey invented the revolutionary Ritchey-Chretien telescope in the early 1900s along with Henri Chretien.
The design, which allowed for a wider field of view, remains in use today.
He also worked on the telescopes at the Mount Wilson Observatory in California, which were used by Edwin Hubble.
Bonhams commented: "Ritchey is arguably the greatest astronomical photographer in history, and is one of the most significant telescope designers.
"At his core, he was a photographer, and he saw the telescope as a lens through which to take ever better celestial photographs.
"Through his efforts in improving the design and construction of telescopes and observatories, and advancing the chemistry of astronomical photography, Ritchey left a legacy that continues today."
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