Asked by: Luke Anderson, Tonbridge
Without gravity, there is no density gradient within the drink, so its bubbles float around randomly inside the liquid. Occasionally a bubble strikes another with enough force to overcome the surface tension and they merge, so over time the bubbles coalesce into a few large bubbles that squash the others into a sort of static foam.
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Authors
Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.
