What can be done by scientists is to create an artificial environment that simulates one or more of the conditions that may be faced by astronauts, and conduct appropriate experiments to evaluate the possible effects on the human physiology.
For example, scientists at the University of Alabama in Birmingham, USA have done exactly this in relation to the possible effects of cosmic radiation on the human heart, details published April 6 2011, in the journal Radiation Research.
Researchers analysed the effect of exposure to iron ion radiation on mice, a radiation commonly occurring in Space, to see if exposure promotes the development of arterial disease (atherosclerosis).
According to Prof. Dennis Kucik, associate professor in the department of pathology, UAB, “It's well known that prolonged exposure to radiation sources here on Earth, including those used in cancer treatment, excessive occupational exposure and atomic bombs, are associated with an increased risk for atherosclerosis. But cosmic radiation is very different from X-rays and other radiation found on Earth. The radiation risks of deep-space travel are difficult to predict, largely because so few people have been exposed."
Results from the research found that permanent damage to the aorta and carotid arteries in mice did take place, which suggests that deep Space missions, such as those to Mars, might present health risks for astronauts from radiation that could give rise to heart problems.
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