Browse Items (26 total)

Reaves, Gibson, W.H. Pickering, Milton Humason, and the Discovery of Pluto, 1983-07-22

"W.H. Pickering, Milton Humason, and the Discovery of Pluto." Talk given by Gibson Reaves at Lowell Observatory, July 22, 1983

Slipher, Vesto Melvin, Letter from V.M. Slipher to Albert Einstein, January 14, 1931, 1931-01-14

A letter from V.M. Slipher to Albert Einstein, inviting Einstein to visit Lowell Observatory and northern Arizona.

Tags: Albert Einstein

Sykes, Stanley, Stanley Sykes small sketchbook, ca. 1950s

A small sketchbook owned by Stanley Sykes. This sketchbook features various landscape drawings of places in California. Sketchbook courtesy of Diana…

Sykes, Stanley, Stanley Sykes large sketchbook, Unknown

Large sketchbook owned by Stanley Sykes. This sketchbook includes drawings of places in Flagstaff, Arizona and unidentified photographs. Courtesy of…

Tombaugh, Muron, Telegram to Clyde Tombaugh from his parents, 1930-03-14

Telegram to Clyde Tombaugh from his parents congratulating him the day after the announcement that he discovered a planet (Pluto)

Tags: Clyde Tombaugh, Pluto

United States Department of the Interior, Map of the Arizona Territory, 1892, 1892

Map of the Arizona Territory used by Andrew Douglass on his trip to find a site for Percival Lowell's observatory in 1894. Douglass' handwritten notes…