Video: Cyclone in a soap bubble

IT LOOKS like a snap from Hubble’s cosmic collection. But this iridescent storm isn’t whirling on an alien planet – it has formed on the surface of a soap bubble.

Led by Hamid Kellay, a group of physicists at the University of Bordeaux, France, heated soap bubbles from underneath to create large vortices like the naturally colourful one pictured. By varying the temperature and rotating the bubbles, they studied how these spinning, storm-like structures develop under different conditions using a camera that shoots up to 500 frames per second.

(Image: Hamid Kellay)


Kellay’s colleague Patrick Fischer is part of a collaborating group of mathematicians that modelled the behaviour of the bubble surfaces. “From birth to death, the vortices reach a peak intensity in the middle of their lives,” says Fischer. This pattern is also seen in tropical cyclones in Earth’s atmosphere, as well storms further afield, such as Jupiter’s Great Red Spot (Scientific Reports, doi.org/qxk).

Although the physics governing soap bubbles is simpler than cyclone science, the models can be used as a starting point for exploring more complex systems. “If we had a better understanding of how the vortices are created, how they move and how they die, we would be able to provide better predictions for cyclone alerts,” says Fischer.

This article appeared in print under the headline “Storm in a soap bubble”