Blowing Bubbles at the ISS
While playing around on the
International Space Station, astronaut-scientist Donald Pettit discovered that in
the absence of gravity, ordinary water would maintain itself in a thin film stretched
across a ring similar to a child's bubble wand. When shaken, the film held, and
would sometimes eject a droplet or two of water - causing the film to get even thinner.
On Earth, the surface tension of plain water is too weak to withstand the gravitational
force. Adding soap to the water greatly increases its surface tension, allowing
the film to persist in a gravitational field. This newfound phenomenon is being
studied now for its application in computational fluid dynamics and turbulence.