Fluid transport and handling in extraterrestrial conditions, i.e. microgravity, require
significantly different system engineering than here on Earth. On Earth, a notable part
of fluid processing units inherently relies on buoyancy to transport and handle fluids. In
space, however, buoyancy effects are negligible due to the strong diminishment of gravity,
resulting in the domination of surface tension forces. Surface tension forces are also
dominating micro-scale processes in gravity, making microfluidics a promising technology
for fluidic transport and handling in microgravity. Recently, three different microfluidicssuitable
fluid behavior phenomena have been studied on the ISS that might further facilitate
the manipulation of fluids in space: capillary-driven flow, thermocapillary Marangoni forces,
and electrolytic gas evolution-driven flow. Furthermore, attention is drawn for strategies to
eliminate unwanted bubbles from liquid bodies in space, as they can damage sensitive
equipment: Mesh-screen capillarity and open wedge channels have been identified as
promising approaches. Finally, the relevance of fluid handling in space is illustrated with
everyday activities during space missions, such as drinking, plant watering, and gathering
biometric data