Exploring Spaceflight Repercussions Upon The Human Body
Beyond the beauty, fascination and the usefulness of spaceflights for the benefit of mankind, there is one dimension that we usually forget: the adverse effects of space upon humans.
The latest findings and achievements in studies about the effects of space on the human body were presented in Shenzhen, the Chinese frontier city of science and technology. Nine astronauts and 150 researchers from 60 countries met there for the 21st IAA Humans in Space Symposium, organized by Beijing Institute of Technology, Space Institute of Southern China and Shenzhen Aviation Association under the aegis of the International Academy of Astronautics, at the end of November.
“We are subject to various medical tests and we conduct experiments in space to test hypotheses developed on earth for the progress of science,” said Dumitru-Dorin Prunariu, retired Romanian astronaut, former president of the Association of Space Explorers, present in Shenzehn as special guest, “we know we are guinea pigs in space.”
Researchers face the challenge of finding solutions to counter the decline of the human body under the extremely demanding conditions of the outer space, especially during the long flights and extra-vehicular activities.
“Microgravity has harmful effects for the human body systems: sharp decline in mechanical loads, alteration of movements biomechanics, increase of inertia, atrophy and structural changes in the skeletal muscles, reduction of the g-load tolerance, disorder in coordination of movements,” explained Inessa B Kozlovskaya and Elena S Tomilovskaya from Russia. “In the 1970s, Russia started to develop countermeasures to be used in space in order to alleviate the condition of the astronauts, such as the treadmill, the bicycle ergometer and the force training devices well as electro-stimulators, the axial loading suit called Penguin and the pneumatic vacuum suit.”
Hans Christian Gunga from Germany said that, “constant brain and body temperature are most important in space”, and “brain temperature decrease with 0.5 degrees leads to impairment of cognitive functions. Changes in body temperature also disable some functions. Humans have a colder nose but warmer face in space due to more infusion of blood. Body temperature increases 60-70% faster in space. Thermoregulation is vital in space. On Earth, we have convection. In microgravity, we have radiation.”
There cannot be life without Sun, explained Gunga, if the Sun forgets to shine for one day, the temperature on Earth would become 0 degrees, and if it forgets to shine for one year, it’ll become – 269 degrees.
Nick Kanas from the US presented in detail the psychological and psychiatric aspects of long duration space flights. He identified many stressors such as “isolation and confinement that do not allow walking outside the spaceship, monotony, and spending too much time with the same people in a confined space, and this is revealed by the diary of cosmonaut Lebedev, for instance, also the high workload stress during dockings and space walks, crew-ground communication…and the 3rd quarter phenomenon, a kind of depression and homesickness”.
The common language may also be a stressor and it matters a lot, “especially during crises, but also when it comes to understanding jokes”! There are also post-return stressors such as “adjustment disorders, mood and thought disorders, asthenization, characterized by physical and emotional fatigue, irritation, appetite ad sleep problems, or attention deficit… Coming back and fame is also something difficult to bear for some astronauts, it totally changes their lives. Buzz Aldrin openly wrote about his depression,” said Kanas.
Interestingly, the findings of the studies conducted on astronauts seem to be culturally linked. For instance, China found no third quarter syndrome during its studies, and asthenization was found only in 50% of cosmonauts while the US does not use this term because it is considered not documented enough scientifically.
Kanas emphasized that these psychological and psychiatric issues must be discussed not only with reference to astronauts working today in space but also in terms of future travelers, such as space tourists, and future long missions for Mars, “when the Earth will be seen no longer like a nearby ball but like a distant dot…” and “astronauts will need 25 minutes to receive an answer to a question when they talk to their families.”
Michel Tognini, French astronaut, former Head of the European Astronaut Centre of the European Space Agency, between 2005 -2011, present in Shenzehn as special guest, explained that, “not too much talk was done in the past about these psychological aspects because flights were short, so astronauts were carefully selected and trained psychologically to cope with the missions. Today, it’s different because of the long flights. A cultural training is also conducted with astronauts so that they could cope with international teams, to know what they can do and what they cannot with their mates during a mission…For instance you don’t touch a Japanese, you allow a distance, and you don’t make jokes like we the French do, while with the Germans, Italians or Spanish, you can make jokes, our cultures are similar….”
The issue of 1-2% loss of bone mass per month and the effects of stress during space flights upon the muscles, cardiovascular system, brain and the food and nutrition issues were explained by Alexander Chouker from Germany. If we keep in mind that “every 90 minutes, a new day starts for the astronauts on the space station!,” we understand why “astronauts have a disrupted circadian rhythms.” They may also experience “oral herpes viral reactivation and rash severity.” as well as “brain pressure increase” and “visual impairment” due to stress conditions such as docking for instance.
The purpose of the Chinese research on the active exoskeleton control technology based on 3E+ (EEG, EMG, ECG, eye movement, camera, pressure and angular info), conducted by Xuejun Jiao, Rui Yin, Jin Jiang and Jinda Feng from China, was to provide intelligent power-assistant equipment for astronauts. Therefore, in order to reduce the astronaut’s task load and to provide energy support, to provide a combination of exoskeleton and BCI ( brain-computer interface). The study turns out to be a breakthrough in this field: “in order to improve the application of the EVA space suit, the robotic system in the outer space will identify the astronaut’s motor intention and control the exoskeleton system by brain activity”.
The human-machine collaboration is an operation of the exoskeleton controlled by hybrid BCI, which represents a fusion of execution, perception and decision levels through multi-sensor technology, including physiological signal, biomechanics information and video info and through a recognition algorithm of motor intention and control algorithm of a delicate operation.
Another experiment made by Jin Jiang, Rui Yin, Xuejun Jiao and Jing Jing Pan from China on the BCI and involving six human subjects confirms that humans can control robotic devices only by brain signal. With the advantage of portability, low-cost and non-invasiveness, BCI based on EEG is seen to be one of the best applications in human-machine interaction for spaceflight tasks. Since the accuracy of the BCI ability to distinguish targets is above 70%, the ultimate purpose of this research is to develop real-time intelligent miniaturization BCI for future EVA (extra-vehicular activities) space suit.
Dumitru-Dorin Prunariu, retired Romanian astronaut, and regular delegate to the UN COPUOS in Vienna for 32 years, special guest to the symposium in Shenzehn, confirms that “China is focused on manned space flights!”
The parabolic flights, used for astronaut training but also for physiology, nano-biology and life support studies, were presented by Markus Braun from Germany who described the German studies conducted in Houston, such as cardiorespiratory kinetics and neuroplasticity in HERA, and the latest advanced technology developed by Germany, such as the compact confocal laser spinning disc fluorescence microscope – FLUMIAS for fast live-cell imaging under real microgravity, as well as the experiment on the Controlled Ecological Life Suport System conducted in Shenzhen with the Space Institute of Southern China.
Despite the difficulties in the outer space, researchers and astronauts are dreaming of a Moon Village. Claudie Haignere, French astronaut, presented the concept of a “permanent lunar infrastructure, a total automated environment that will be open to multiple users, for tourism and commercial uses, with a new type of governance”.
To note that the Moon Village has progressed from a vision to a tangible infrastructure currently being designed in detail, which has been possible as a result of cooperation in joint projects between the European Space Agency, JAXA – Japanese Space Agency, CSA – the Chinese Space Agency, and many other entities, both public and private.
With more than 100 papers presented, the 21st IAA Humans in Space Symposium that took place in Shenzhen provided huge amount of scientific data, as well as an overview of the current status of research in this field. International cooperation appears as enhanced. Many references to jointly-conducted comprehensive projects were made during the days of the symposium.
A quick glance over the papers presented during this bi-annual IAA HIS Symposiums over the last years reveals that space research is advancing tremendously – more in-depth, gradually streamlined at the level of the cell, and more diversified, with the purpose to counter the effects of space on the human body. Based on previous findings, researchers resume their work through new approaches and new correlations.
As the number of human space activities is increasing and being expanded into human lunar, asteroid and Mars explorations, and with space tourism also a purpose, scientific research helps in preparing the best conditions.
Moreover, many findings of these space experiments are applied further on in the human medicine such as serious neurological conditions, neuroendocrine or cardiologic.
