An unprecedented microgravity observation of maximal shape oscillations of a suifactant-bearing water drop the size of a ping pong ball was observed during a mission of Space Shuttle Columbia as part of the second United States Microgravity Laboratory-USML-2 (STS-73, October 20-November 5, 1995). The observation was precipitated by the action of an intense sound field which produced a deforming force on the drop. When this deforming force was suddenly reduced, the drop executed nearly free and axisymmetric oscillations for several cycles, demonstrating a remarkable amplitude of nonlinear motion. Whether azising from the discussion of modes of oscillation of the atomic nucleus, or the explosion of stars, or how rain forms, the complex processes influencing the motion, fission, and coalescence of drops have fascinated scientists for centuries. Tberefore, the axisymmetric oscillations of a maximally deformed liquid drop are noteworthy, not only for their scientific value but also for their aesthetic character.
Apfel, R.E., Tian, Y., Jankovsky, J., Chen, X., Shi, T., Holt, R.G., Trinh, E., Croonquist, A., Thornton, K.C., Sacco, Jr., A., Coleman, C., Leslie, F.W., Matthiesen, D.H., Drops in Space: Super Oscillations and Surfactant Studies, 3rd Microgravity Fluid Physics Conference, NASA Lewis Research Center, Cleveland, OH, CP 3338, pp. 585-590, June 13, 1996.