Page 61 - International Space Station Benefits for Humanity, 3rd edition.

research team found that protein expression associated
with auxin signaling was decreased while stress
response proteins increased (Mazars et al., 2014). The space station provides an
A series of plant experiments performed on the space excellent platform for testing
station showed that the development cycle of plants,
their genetic status, morphological and biometric and developing devices called
indicators, and basic processes (i.e., photosynthesis, dosimeters that detect and
gas exchange, formation of generative organs) do not quantify radiation exposure.
depend on the spaceflight conditions (Sychev et. al,
2011; Sugimoto et. al, 2014). Higher plants’ seeds
formed in microgravity were biologically full-featured,
and the plants obtained from these seeds did not differ
from ordinary “earth” plants. Results also showed that station revealed a substantial lack of uniformity in the
at least four successive generations of higher plants can depth-dose and surface-dose distributions for spherical
grow and develop in spaceflight conditions. Developing “phantom” that simulated an astronaut’s body, thus
technology for cultivation of higher plants will offer the giving an indication of impacts on an actual astronaut’s
possibility of introducing greenhouses as typical human body. The effectiveness of the radiation protection
life support systems during exploration-class missions. properties of materials containing hydrogen to reduce
the doses of charged particles and neutrons was
demonstrated while using additional protection in
Radiation crew quarters. The radiation exposure rate in ISS
As astronauts will soon start exploring outside Earth’s compartments was assessed for the period of active
protective magnetic field, they will be exposed to more sun near the maximum of the solar activity in the final
space radiation such as cosmic rays or solar particles. stage of its growth (Ambrožová, et al., 2017; Khulapko
The space station provides an excellent platform for et. al, 2015; Khulapko et. al, 2014; Khulapko 2016).
testing and developing devices called dosimeters that Several attempts to study radiation used living
detect and quantify radiation exposure. A combination organisms as “biological dosimeters,” which revealed
of passive and active dosimeters on the space station genetic mutations within the nematode C. elegans,
show how the radiation environment—both total and contributed to understanding how DNA is affected
absorbed dose and radiation spectrum—inside the by space radiation exposure (Zhao et al., 2006; Jamal
ISS Columbus module changes through the course et al., 2010). Radiation damage is one of the major
of the solar cycle, as well as solar events and with risks of deep space missions; therefore, data collected
alterations in the ISS attitude (Berger et al., 2016). on the space station and technologies developed by
Furthermore, the effects of spacecraft attitude, vehicle the international community will play a major role in
docking and local shielding effects on the radiation ensuring the safety of space exploration.
environment have been observed. This helps in
understanding how the radiation environment is affected Kevlar fabric material studied on the space station
both by the space environment and by the spacecraft, had comparable shielding properties with polyethylene
which is valuable information for the ISS as well as material, which is a traditionally favored radiation
future space exploration missions. Neutron “bubble shielding material. These results suggest that the
detector” dosimeters have characterized neutron impact resistance and flexibility make Kevlar an optimal
doses and energy within the ISS over several years. candidate as a performing element in an integrated
Results showed that despite large differences in solar shielding approach (Narici et al., 2017).
activities, the neutron environment was fairly constant
in ISS modules (Smith et al., 2012; Smith et al., 2015).
The data will also support the development of effective Materials, Fluids and Combustion
protective measures for deep space missions. Much of our understanding of physics is based on the
Results of studies that preceded the ISS quantified inclusion of gravity in fundamental equations. Using a
radiation exposure to keep astronauts safe while laboratory environment found nowhere else, the ISS
outside the ISS, and found that they received more provides the only place to study long-term physical
radiation to the skin, eyes and blood-forming organs effects in the absence of gravity—without the
than when inside the spacecraft’s protective shielding complications of gravity-related processes such as
(Thomson, 1999). Another investigation on the space convection and sedimentation. This unique microgravity

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