Lunar halos like this one, captured in Mogilev, Belarus, appear only when there’s substantial numbers of ice crystals in the atmosphere. Most often they’re from very thin cirrus clouds hovering at or above 20,000 feet. All those hanging bits of moisture refract light from the moon (or the sun, in a solar halo), making it appear as if there’s a halo around it. Mikhail Kapychka
Sara Chodosh was an editor at Popular Science for more than 5 years, where she worked her way up from editorial assistant to associate science editor. In that time she slowly took over running the Charted section of the now-defunct print magazine. Her love of graphics eventually led to her current job as a graphics editor at the New York Times. Contact the author here.
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