pyrheliometer
Quick Summary
A pyrheliometer is an instrument used to measure the sun's radiant energy as it reaches Earth. This measurement is part of pyrheliometry, the study of the sun's heat. Sunlight itself is solar radiation visible at Earth's surface and is composed of visible light, ultraviolet light, and infrared radiation.123
The Eppley pyrheliometer, for example, measures both the duration and intensity of sunlight. It works by comparing the heating of a blackened ring versus a whitened ring, which generates an electromotive force proportional to the sunlight's intensity.3
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