dpm

The Drop Physics Module has been developed so scientists can study several fluid physics phenomena: a simple surface, such as the sphere formed by a liquid drop in the absence of gravity; how a drop reacts to different forces (drop dynamics); and how surfaces and compound drops - a drop of one liquid surrounding a drop of a different liquid - interact.
Payload on STS-50, Spacelab/USML-1

The Drop Physics Module has been developed so scientists can study several fluid
physics phenomena: a simple surface, such as the sphere formed by a liquid drop in
the absence of gravity; how a drop reacts to different forces (drop dynamics); and
how surfaces and compound drops - a drop of one liquid surrounding a drop of a
different liquid - interact.

Payload on STS-73, USML-2 (DPM-2)
Payload on STS-50, Spacelab