These entrancing patterns are created by soapy molecules attracted to the surface of liquid crystal droplets in water.
Liquid crystals, fluids with aligned phases of constituent molecules, are used in everything from computer and television displays to mood rings. Since liquid crystals are made of rod-like molecules, they have special optical properties, such as changing color as they interact with electrical signals or light.
Surfactants like soap are attracted to the oil-like liquid crystals, changing the arrangement of the liquid crystal molecules and creating the striking patterns. Adding more soap to the solution changed the patterns (see animation below), while adding water reversed the changes.
Researcher Lisa Tran, a graduate student at the University of Pennsylvania in the US, also noted that – while the detailed patterns can only be seen under a microscope – changing the concentration of soap produced changes in the solution that were visible to the naked eye. This means the technique has potential for use in testing liquids for poisons or other contaminants.
Read science facts, not fiction...
There’s never been a more important time to explain the facts, cherish evidence-based knowledge and to showcase the latest scientific, technological and engineering breakthroughs. Cosmos is published by The Royal Institution of Australia, a charity dedicated to connecting people with the world of science. Financial contributions, however big or small, help us provide access to trusted science information at a time when the world needs it most. Please support us by making a donation or purchasing a subscription today.