Illustration depicting a Pyrheliometer, an instrument for the measurement of direct beam solar irradiance. Sunlight enters the instrument through a window and is directed onto a thermopile which converts heat to an electrical signal that can be recorded. Dated 19th century

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Size: 3246px × 6461px
Location:
Photo credit: © World History Archive / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: 1873, 19th, archival, archive, beam, century, conversion, direct, electrical, heat, historical, history, illustrated, illustration, instrument, irradiance, measure, measurement, measuring, pyrheliometer, science, signal, solar, sunlight, technology, thermophile