Truth serum, zero-G and the Vomit Comet: the hunt for deep space flight solutions

Posted on: 25 September 2018

Engineers from Trinity are among an elite team of researchers with a unique tale to tell, having recently returned from a research expedition to France where they rode the ‘Vomit Comet’ – a modified aeroplane that, when put through unusual paces by expert pilots, can create a zero-gravity environment. The zero-G is critical as it enables the team to simulate outer space-like conditions and conduct experiments that could offer solutions to allow people to travel with spacecraft when exploring deep space.

The research team, which guides and advises the European Space Agency (ESA), is primarily concerned with better understanding how water behaves in the absence of gravity (in space). This is because water (or steam, specifically) is seen as the golden bullet for powering spacecraft deep into space. In contrast to solar energy, or other options, steam holds by far and away the greatest potential as there are megawatts of power that could be unlocked.

In addition, the team is keen to better understand how water behaves in zero-G because there are many other critical roles it could play if we learn how to properly manage it. For example, we need to be able to tightly regulate its condensation, humidification and dehumidification. This is because astronauts need to work in an air-conditioned, hygienic environment, water needs to be purified for consumption, and electronic equipment needs to be cooled to prevent heat stress.

A number of experiments on the recent trip were led by Trinity’s Dr Tony Robinson and Dr Seamus O’Shaughnessy. Dr Robinson is Associate Professor in Trinity’s School of Engineering, and a Funded Investigator with CONNECT, the Science Foundation Ireland Research Centre for Future Networks, and Dr Seamus O’Shaughnessy is Ussher Assistant Professor in Energy & Sustainable International Development. Their team collaborated with others from the University of Pisa, led by Professor Paolo Di Marco.

The teams from Trinity and the University of Pisa spent two weeks planning and executing experiments on their latest venture aboard the Novespace Zero-G ‘Vomit Comet’. The researchers involved make use of this specially modified A310 plane, which cruises at 24,000 ft before making a sudden 45? angle ascent to 32,000 ft, where it levels off. At this point, everyone on board experiences 25-30 seconds of zero-G before the nose of the plane makes the opposite 45? angle descent and ultimately levels off at cruising altitude once more. The manoeuvre is known as a parabola, and is so unorthodox that the computers on modern-day planes of that size do not permit pilots to make it.

Despite the uniqueness of the parabola, Dr O’Shaughnessy explained that the manoeuvre is safe when conducted by the right hands, but it is so physically jarring that many people experience extreme nausea – hence the plane being nicknamed the “Vomit Comet”. So, what’s the solution to preventing this debilitating sickness? A dose of scopolamine – an agent previously used in interrogation as a “truth serum” – which thankfully is also a powerful antidote for severe motion sickness.

After two successful campaigns, and many months of data processing and analysis, the researchers have discovered some key fundamental mechanisms of evaporation that were previously unknown, and this knowledge is being prepared for publication in top scientific journals. Onward from here, they intend to use this new knowledge to fly again to explore the effects of intense electric fields on evaporation, as it now appears possible to use electric stresses to control evaporation, and this could eventually lead to highly engineered intelligent and compact thermal equipment on spacecraft, which is the ultimate goal.

Dr Robinson said: “Ultimately we want to engineer thermal equipment for spacecraft and satellites, but we are still grappling with the science of how liquids evaporate and condense in weightlessness. It’s a tough multi-scale and multi-physics problem and we have very little hard data in the space environment.”

“Basically we are trying to drill down to the very basic physics of how water evaporates in space, and the idea is we keep building upward from here until we know enough that we can engineer really lean equipment for spacecraft. In space there is no room for overdesign and certainly no room for mistakes.”