Some phenomena that appear to be well understood are much more mysterious than it seems. In spite of the numerous applications that rely on the presence or absence of bubbles, no advanced scientific studies had been carried out so far into how bubbles form (video). A team of researchers tackled this question and developed a self-sustaining bubble machine in the laboratory. The researchers have managed to determine the minimum speed at which air must be blown on a soap film to form bubbles, under various experimental conditions.