Term: AM 0 sunlight
https://doi.org/10.1351/goldbook.A00312

Definition:
Solar irradiance in space just above the atmosphere of the earth on a plane perpendicular to the direction of the sun (air mass, AM, zero). Also called extraterrestrial irradiance.

Related Terms:
1) am 1 sunlight (http://doi.org/10.1351/goldbook.A00313).
2) irradiance (http://doi.org/10.1351/goldbook.I03254).

Source: PAC, 2007, 79, 293. 'Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)' on page 302 (https://doi.org/10.1351/pac200779030293)

Citation: 'AM 0 sunlight' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.A00312

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