In TSJ 31.3's "On the Bubble," Mike Stewart (@mikestewart) consults with dark matter physicists about the mechanics of wave vortices. To read the full feature, pick up a copy of our latest issue.⁠ ⁠ "In a more practical application for surfers," writes Stewart, "I’ve broken down some of these images to hopefully serve you when you find yourself in or around the tube. The first step in avoiding calamity is to have a better understanding of the playing field, in this case the hazards and dynamics of a breaking wave."⁠ ⁠ Photo and annotations by Stewart.