Pluto discovery glass plate. This glass plate shows several objects (circled) in the same region of the sky, one of a series of photographic plates ob

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Pluto discovery glass plate. This glass plate shows several objects (circled) in the same region of the sky, one of a series of photographic plates obtained by US astronomer Clyde Tombaugh (1906-1997) in January 1930. This plate is the one obtained on 23 January. By comparing the plates and seeing which objects were moving relative to the background stars, Tombaugh was able to identify a new planet which was named Pluto. Pluto was redesignated a dwarf planet in 2006. This glass plate is among the exhibits held by the National Air and Space Museum at the Smithsonian Institution, Washington DC, USA.

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Size: 5280px × 4334px
Photo credit: © National Air and Space Museum, SMITHSONIAN INSTITUTION/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

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