Astronomy Today

Photography and Photometry

What is photometry?

Photometry is the astronomical measurement of brightness (also known as flux or intensity) and color. Photometric intensity is measured as the amount of light energy that strikes a certain surface area on Earth over a certain period of time—in other words, how bright it appears—and is usually measured in units such as “ergs per square centimeter per second,” or in terms of apparent magnitude.


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