This set of two original photographic plates is of the globular cluster Messier 13 (M13), one of the brightest clusters of its type in the northern skies. These plates were obtained by astronomer Wayne Osborn in July 1968, working with other astronomers as part of an extensive systematic series of photographic and photoelectric observations in the 1960s through 1980s searching for stars that vary in light in the cluster. Known as Cepheid variables, their variation reveals their intrinsic brightnesses, which yields a measurement of distance to the cluster. The photographic observations were made at the 61-inch (1.5 meter) astrometric reflector at the U. S. Naval Observatory Flagstaff Sation.
Display Status
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.
Object Details
Type
INSTRUMENTS-Scientific
Owner
Pisgah Astronomical Research Institute
Photographer
Wayne Osborne
Dimensions
3-D: 17 × 12.7 × 0.1cm (6 11/16 in. × 5 in. × 1/16 in.)
2-D - Unframed (H x W) (Paper Sleeve): 19 × 14cm (7 1/2 × 5 1/2 in.)
Materials
Glass with photographic emulsion, within paper folder
Inventory Number
I20171422002
Credit Line
On loan from Pisgah Astronomical Research Labatory (PARI), Rosman, NC
Data Source
National Air and Space Museum
Restrictions & Rights
Usage conditions apply
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