Water in space. 1 Experiments in micro gravity

On November 23th, Diego Pozo, a Spanish space engineer, offered to the Young Water Professionals network a fantastic webinar about “Water in Space”.

In this series of 4 articles Diego explains us the content of his webinar for the people who couldn’t assist and for the not YWP members. Was a great webinar and is a great series of articles, so, in the name of all YWP’s all over the world, thank you Diego!!


Water is one of the key elements of human life, and of life as we know it, and as we search for it. The Space endeavor of Mankind has thus needed to privilege the study of water needs as a necessity to reach for the stars, be it in the first expeditions of Gagarin, Tereshkova or Shepard, the Apollo journeys to the Moon, or as an integral part of the MIR and International Space Station (ISS) ventures with the Environmental Control and Life Sustain System (ECLSS). Furthermore, the development of Satellite and Remote Sensing Technology has given humankind the possibility of monitoring vital resources for its existence, and water applications such as ocean, climate and pollution surveillance come as some of the very primary and fundamental applications for the funding governments of the public programs.

There are several reasons for which Water is important for the Space industry. Let’s start with the most basic one: we are humans, thus we need water.

The current Space context is dominated by a Hashtag, as most things in our time, and this is #JouneyToMars. As a former member of the International Space Station operations team, I received a bi-weekly dispatch from NASA on the current state of affairs. Every single email was written around that hashtag: latest developments on the European Service Module (ESM) developed by Airbus Defence and Space (ADS) for the Orion capsule Mission to the Moon and Mars; news on the privatization of the Space and especially the launcher sector to allow SpaceX, BlueOrigin, Orbital ATK or Sierra Nevada Corporation to build their new prototypes to take human to the ISS, the Moon and beyond; plans and experiments performed for Human Colonization of space bodies, etc. Not to forget the commercial endeavors for Space Tourism led by Virgin Galactic, among others. But, what does humanity need to first make it and then be able to sustain life on Mars?

We find answers in the first orbits around Earth performed by Russian Cosmonauts in the 60s. It was definitely a trial and error project, including the fly of the very famous dog Laika, Alexey Leonov’s first Spacewalk (nearly fatal due to the stiffness of its spacesuit in vacuum, which he managed to bend with a release valve in extremis to get back into his Soyuz capsule), or several unmanned and proof of concept missions, that we still launch today e.g. LISA Pathfinder for gravitational waves detection, as preparation of the LISA missions. When it comes to Space and human beings, the tests have been performed on ISS, and on human bodies as those of Astronauts and Cosmonauts, as well as of Taikonauts but well, not much data has been shared about those this far.

When you think of the daily routine of an ISS Crew Member, you may think of floating around, gazing at the beauty of our boundary and frontier-less (round) Earth seen from above (its orbital space, to be precise), which is pretty much what they do but in the frame of an 9 hour journey, with the weekend devoted to Voluntary Tasks, Repairs if needed, or just relax and fun (again, floating around like an Ang-Lee film ninja). Their days start with breakfast, followed by a Morning DPC (debrief) by Mission Control in Houston, Moscow, Munich and Tsukuba (followed also by many Payloads -on board experiments- operational centers, and at times related Principal Investigators and Scientists whose experiments they will be manipulating). The day is closed by an evening DPC. Each day, they need to perform at least 2h of exercise to avoid Muscular and Osteo atrophy and alterations. After all, we are not made to be in Space. But that may evolve, as we have done for centuries on the surface or Earth.

The way operations are performed, is through On Board Procedures, sort of instruction manuals, that they must follow step by step, informing the Operators on Ground either via the Voice Loop or via video (if requested), of how far ahead they are on the steps. Taking Europe as an example, the Flight Control Team (FCT) is based in Oberpfaffenhoffen (Munich), with several Payload Operations Facilities in different countries. The experiments are classed as Class 1, 2 or 3. Class 1 takes basic resources (power, water, gases, electricity) from ISS, class 2 are branched to Class 1, and Class 3 are mostly stand-alone, asocial dudes. Water and fluids experiments are so important, that on the European Columbus Module (EC-1), one of the 4 Class 1 Payloads is devoted to if: the Fluid Science Laboratory (FSL), and many other fluid related experiments are connected to other Class 1 facilities, such as the European Drawer Rack (EDR), where the Facility for Adsorption and Surface TEnsion Research (FASTER) experiment found its home.

FSL Facility. Source: European Space Agency

FSL has a Thermal exchange module, an Experiment Container (EC) module for fluid cells with dedicated video surveillance and ECH20 cooling system, a diagnosis module with halogen lamp, interferometers for Electronic Speckle Pattern, holographic, Wollaston and Schlieren; and a laser unit. An additional module is the Microgravity Vibration Isolator Subsystem (MVIS) to isolate the experiment from residual ISS perturbations.

FSL’s EC. Source: European Space Agency

FSL Interacts with Columbus module, being a Class 1 Payload, with an N2 gas input, the waste as output, and the different connections for the EWACS (Emergency, Warning and Caution System), power, video and data.

FASTER experiment. Source: Europan Space Agency

But fluidic experiments can not only be performed in FSL. Other facilities provide the means for them. FASTER experiment (Figure 2) was one of the most complicated ones I’ve dealt with, due to the need for real-time following of the mixture of two liquids on ground by the operations and the scientific team. The reason being, a bad mixture or equipment reaction could endanger the whole facility, and bring an end to the experiment. And you cannot just order new supplies on Amazon (yet) when you are out there (not up or down there). It must be borne in mind that the Space one is very conservative industry, where if something works fine you just do not change it: we still use the Soyuz capsule Gagarin used, the Proton rocket from the Space Race, and Columbus recorded on Tape until 2012, just to mention a few. That is partly why, we ensure and reassure that water and human survival will not be a problem on ISS, the Moon, Mars or anywhere.

Contained in the EDR Class 1 Payload, the experiment in itself had as purpose, for several liquid samples, to study the links between the physical chemistry of the droplets interface, the liquid films and the collective properties of an emulsion in the absence of gravity. As for its operational concept, a drop of liquid is created in a matrix chamber made of another liquid (non- miscible with the drop) and stimulated with different kinds of stimuli (pressure variation) by means of an actuator, which can be in turn the active compensation piston or the Piezoelectric transducer. The difference of pressure across the drop interface is calculated from the pressures sensors readings acquired in the two chambers. In addition a camera is acquiring the profile of the drop. The experiment had to be repeated at several fluids temperatures (the maximum temperature range is 10-40°C) and at several surfactants concentrations (by mean of the surfactant injection). Eventually two magnification ratios were available.

There were companies behind FASTER, to improve their understanding and modelling of the forces that result from liquid interaction, in order to update their processes and production accordingly.


Next article: Water in space. 2 Water and wastewater



  1. Status of ISS Water Management and Recovery; L. carter, C. brown, N. Orozco, NASA Marshall Space Flight Center, for the American Institute of Aeronautics and Astronautics
  2. Upgrades to the ISS Water Recovery System; M. Pruitt, L. Carter, R. M. Bagdigian and M. J.. Kayatin, NASA Marshall Space Flight Center, for the  45th International Conference on Environmental Systems, 2015
  3. NASA Science: Water on the Space Station. Link: 
  4. ESA’s Moon Village article. Link:
  5. Austrian Space Forum for analog Astronauts. Link:
  6. ESA’s JUICE. Link: 
  7. Exoplanets list within the habitable zone in Wikipedia. Link: ]; as well as the quest for Exoplanets, link:
  8. ESA’s Rosetta main website. Link:
  9. Rosetta wakes up from hibernation. Link: 
  10. Rosetta unveils comet’s water cycle. Link: 
  11. ROSINA instrument and comet’s water cycle. Link:
  12. ROSINA instrument website. Link:
  13. Evolution of water production of 67P/Churyumov–Gerasimenko: an empirical model and a multi-instrument study; various authors; September 2016; Monthly Notices of the Royal Astronomical Society, Volume 462, Issue Suppl_1, 16 November 2016, Pages S491–S506. Link:
  14. GSA website. Link: