Definition of "actinometry" []

• The measurement of the heating power of electromagnetic radiation, especially that of solar radiation (noun)
• The measurement of the chemical or actinic energy of light (noun)

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• "These is also a photometric photographic catalogue of the stars nearest to the pole in PARKHURST's “Yerkes actinometry” (1912), [11] which contains all stars in B."
• "n. - instrument measuring heating power of the sun's rays; Photography, instrument for calculating exposure times. actinometry, adj."