Dust particles, wind and aerodynamics could steer some flakes toward a three-sided fate
Flurries of questions about mysterious triangle-shaped snowflakes may soon subside, thanks to new research on snowflake formation. Most snowflakes are hexagons because of the arrangement of hydrogen bonds in the water molecule. But the new study, appearing online at arxiv.org (http://arxiv.org/abs/0911.4267) and in an upcoming issue of The Microscope, suggests that after hexagonal flakes, oddball triangular flakes are the most prevalent.
Study coauthors Kenneth Libbrecht and Hannah Arnold of Caltech in Pasadena propose an aeronautical reason for the triangular geometry. The results help solve the very old puzzle of how the unex