Campbell-Stokes sunshine recorder. This instrument design has been used worldwide for many years. The recorder here (a back-up for a more modern desig

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Campbell-Stokes sunshine recorder. This instrument design has been used worldwide for many years. The recorder here (a back-up for a more modern design) is over 90 years old. It is used to record daily sunshine duration. Sunlight passing through the glass ball, which is mounted at an angle adjusted for the latitude, is focused onto a recording card mounted on the other side of the metal bowl (lower centre). The movement of the Sun across the sky chars a trace along the recording card. Different shaped recording cards, marked by hour divisions, are used for different seasons. Photographed at SMHI, the Swedish Meteorological and Hydrological Institute, Norrkoping, Sweden.

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Size: 3413px × 5120px
Photo credit: © DAVID HAY JONES/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: astronomy, cosmology, joshua, monument, nat., natl., science, star, stellar, trail, trails, tree