Photograph by Kenneth G. Libbrecht.
The snowflakes grew under carefully controlled conditions. You may see a movie of the snowflakes forming in the Times article cited in the caption. They seem to be clearing out an area in which to grow; the surrounding dots are water droplets. For more photographs, see here. For an explanation of why all snowflakes are not identical and more, see here. For an answer to the question, “What’s it good for?” see here. The photograph was backlighted, with no phase contrast or other specialized techniques. Photograph copyright 2016 by Kenneth Libbrecht. All rights reserved. Used by permission.