London: A new research has revealed that cosmic radiations might not be as harmful as previously thought, making space travelling relatively safer for future.
The analysis comes from the MATROSHKA experiment data, the first comprehensive measurements of long-term exposure of astronauts to cosmic radiation, which has now been completed and the experiment was carried out on board and outside of the International Space Station.
Among the many life-threatening hazards to the space traveller, cosmic radiation is a major one, considerably limiting the time astronauts may spend in space without incurring excessive risk to their health from too high a dose of this ionizing radiation.
To determine the actual doses of radiation which astronauts undergoing long-term space travel are exposed to, the European Space Agency (ESA) in collaboration with research institutions from Germany, Poland, Austria, Sweden and Russia, designed and carried out the MATROSHKA experiment.
A phantom closely mimicking the human body was fitted with several thousand detectors, most of which were manufactured at the Institute of Nuclear Physics of the Polish Academy of Sciences (IFJ PAN) in Krakow, Poland.
The main hazard to the astronaut's health due to exposure to cosmic radiation is the increased probability of developing cancer in his or her body. This probability however is quite dependent on the type of radiation the astronaut is exposed to. Most of the natural sources of ionising radiation on Earth produce electromagnetic radiation of high energy - gamma rays.
On the other hand, in cosmic rays, energetic protons or heavier ions dominate, which are much more effective in creating cancer cells. Thermoluminescent detectors are unable to distinguish between gamma rays or ions, therefore the phantom was also equipped with plastic track detectors in which tracks of protons or heavier ions could be measured.
From the results of the MATROSHKA experiment the scientists conclude that travel of astronauts to the Moon or to Mars may be somewhat safer in terms of their radiation hazard than presumed so far. Nevertheless, the doses the space travellers are likely to receive, even though being lower than thought earlier, would still remain dangerously high.