Fluid Mechanics and Systems Biology for Understanding the Cosmic Distribution of Life: A Review

Abstract

Due to progress in instrumentation both in cryogenics and in space exploration, the 20th century witnessed the extension of fluid mechanics applications in two novel systems. While the major aim for the first of these two cases—low temperature physics—was to understand the underlying microscopic theory, in the second case of fluid mechanics in the outer Solar System the major problem was, and still is, one of instrumentation, rather than theory. This second kind of environments may provide hints regarding the central problem of astrobiology, namely the search for life outside our own planet. The Galileo Mission (1995–2003) allowed closer probing of the Jovian satellite Europa, both with imaging techniques, as well as with spectroscopy of its icy surface over a deep ocean that is covered with chemical elements. Other examples of oceans are found in Ganymede and Callisto, two other icy Galilean moons, but possibly these oceans are not in contact with a silicate core, as in the cases of the life-friendly world: the Earth. In addition, Europa, with possibly the same internal geological structure as our planet, is also potentially a life-friendly world. These appealing phenomena are currently the source of plans for the next European mission to Europa that will provide a baseline for the search of life. For this purpose knowledge of our oceans will guide us in the search of life in other solar system oceans. These possibilities have encouraged underlining technologically feasible proposals for delivering small missiles (“penetrators”) with appropriate instrumentation. Whenever compatible with the available payloads, one objective of these instruments has been to identify bioindicators. We are interested essentially in understanding the surficial sulfur stains of Europa’s icy surface. Although not included in the most recent approved mission for Europa, penetrators remain a valid alternative in lunar research that we have shown to be relevant to the basis of astrobiology. In this context we have argued that already existing miniaturized mass spectrometers are particularly relevant. The arguments of this work bring together fluid mechanics, systems biology, and feasible cutting-edge technology.