  The first large length-scale capillary rise experiments were conducted by R.
Siegel using a drop tower at NASA LeRC shortly after the 1957 launch of Sputnik
I. Siegel was curious if the wetting fluid would expel from the end of short
capillary tubes in a low-gravity environment. He observed that although the
fluid partially left the tubes, it was always pulled back by surface tension,
which caused the fluid to remain pinned to the tubes' end. By exploiting tube
geometry and fluid properties, we demonstrate that such capillary flows can in
fact eject a variety of jets and drops. This fluid dynamics video provides a
historical overview of such spontaneous capillarity-driven droplet ejection.
Footage of terrestrial and low earth orbit experiments are also shown. Droplets
generated in a microgravity environment are $10^6$ times larger than those
ejected in a terrestrial environment. The accompanying article provides a
summary of the critical parameters and experimental procedures. Scaling the
governing equations reveals the dimensionless groups that identify topological
regimes of droplet behavior which provides a novel perspective from which to
further investigate jets, droplets, and other capillary phenomena over large
length scales.
