Blink Comparator
date: label: date made
content: 1920s
notes: label: Description
content: Astronomers compare different photographs of the same region of the sky taken at different times, in order to discover and measure minute movements of celestial objects. Frank Schlesinger, director of the Yale University Observatory, designed this blink comparator in the early 1920s, and had it built at Yale for the Harvard College Observatory. Rather than placing two photographs side-by-side—as was done with the Zeiss blink comparator—Schlesinger’s instrument put one photograph above the other.
label: Description
content: Willem Jacob Luyten, a Dutch astronomer who became a professor at the University of Minnesota, brought this comparator with him when he moved to Minneapolis in 1931. He used it to detect and measure the proper motions of 94,263 stars.
label: Description
content: Ref: Frank Schlesinger, “A Simple Machine for Comparing Two Celestial Photographs,” <i>Astronomical Journal</i> 37 (1926): 45-47.
label: Description
content: Arthur R. Upgren, “Willem Jacob Luyten (1899-1994),” <i>Publications of the Astronomical Society of the Pacific</i> 104 (1995): 603-605.
place: label: place made
content: United States: Connecticut, New Haven
topic: label: Subject
content: Science & Scientific Instruments
setName: label: See more items in
content: Medicine and Science: Physical Sciences
creditLine: label: Credit Line
content: Space Science Center, University of Minnesota
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: 1992.0110.01
label: catalog number
content: 1992.0110.01
label: accession number
content: 1992.0110
objectType: label: Object Name
content: blink comparator