Halos represent a common and imposing atmospheric optics phenomenon whose displays are caused by tiny air-borne ice crystals. Their variety stems from a certain set of orientation classes to which these crystals belong. We present a robust and inexpensive device, made of modular components, that allows for the replication of most of these orientation classes in the laboratory. Under the illumination of light, the corresponding artificial halo counterparts emerge. The mechanical realization of this device allows a thorough understanding and demonstration of these beautiful atmospheric optics phenomena.
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Most electronic stores will have these parts, for instance: <https://www.adafruit.com>.
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See supplementary material at http://dx.doi.org/10.1119/1.4953342 for additional images, including the spherical projection screen setup.
© 2016 American Association of Physics Teachers.
2016
American Association of Physics Teachers
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