You might not recognize Ken Libbrecht on the street, but the odds are good you’ve seen his handiwork. Libbrecht is a physicist specializing in snowflakes, and his passion for ice crystals has made him something of a hot commodity.

Libbrecht’s interest in snowflakes came to him relatively late in life, well into his physics career. He was in North Dakota visiting family when a trip outside inspired a deceptively simple question, he told Smithsonian in 2013. “I suddenly thought, ‘Why don’t I understand more about these snowflakes?’”

The reason, it turned out, was that science in general doesn’t understand a lot about how snowflakes form. So Libbrecht started examining, photographing, and cataloging the snowflakes he found. His stunning snowflake pictures have been collected into a number of popular coffee table books.

Still, he had questions, so Libbrecht built a snow machine. But rather than spewing feet of precipitation, the equipment grows a single snowflake at a time. "I call them 'designer snowflakes,'” he told Smithsonian, “because you can change the conditions as you grow them and predict what they'll look like.” The snowflake generators have indeed led to advances in crystallography and snow science, and Libbrecht’s work caught the attention of Disney animators, who brought him on board to ensure that their fairy tale flakes were true to life.

There’s one question that dogs Libbrecht wherever he goes: Is it true that no two snowflakes are alike? Here, he gets philosophical. “It depends on just what you mean by ‘alike,’” he wrote on his website, “and on just what you mean by ‘snowflake.’”

Listen to Libbrecht talk about his work and gaze at some gorgeous snowflakes in the video from Great Big Story above.

Header image from YouTube // Great Big Story