Radiation Risk Of Space Tourists
- Paper number
IAC-07-A1.9.-A2.7.04
- Author
Mr. Peter Szanto, Hungarian Academy of Sciences KFKI Atomic Energy Research Institute, Hungary
- Coauthor
Mr. Yu. A. Akatov, Russia
- Coauthor
Mr. István Apáthy, Hungarian Academy of Sciences KFKI Atomic Energy Research Institute, Hungary
- Coauthor
Mr. V. V. Arkhangelsky, Russia
- Coauthor
Dr. Sándor Deme, Hungarian Academy of Sciences KFKI Atomic Energy Research Institute, Hungary
- Coauthor
Mr. Charles Simonyi, United States
- Year
2007
- Abstract
Astronauts working and living on ISS are only partly protected from the cosmic radiation by the magnetosphere of the Earth and the wall of the space station. The dose of the ionizing radiation they are exposed to has to be measured and taken into account as a source of risk, as it is two orders of magnitude over the dose levels typically encountered on the Earth’s surface due to natural radiation. The KFKI Atomic Energy Research Institute of the Hungarian Academy of Sciences has developed an onboard thermoluminescent dosimeter (TLD) system called Pille to measure and evaluate the dose rate on board space vehicles. The different versions of the Pille system have provided personal dose and dose distribution data on all space stations since 1980.
The long-term average dose rate on the ISS measured by the Pille varies between 6 µGy/h and 8.5 µGy/h at different locations while the short-term dose rate may be much higher. It depends on the shielding of the location, the orbital altitude and the attitude of the space station, the temporary solar events and the solar cycle. The influence of the South Atlantic Anomaly on the doses can be seen clearly as well: the dose rate inside the anomaly is 50-60 times higher than outside.
The lifetime dose limit for astronauts is defined as the dose equivalent that doubles the risk of fatal cancer. This dose limit is between 0.4 Sv-2.9 Sv depending on the sex and the age of the astronaut. The 1.1 mGy dose/week measured by Pille is equivalent to 3.3 mSv dose equivalent/week if both the radiation weighting factor and the radiation components not measured (neutron radiation, LET > 10 keV/µm, etc.) due to the limitations of the TL technique are taken into account as well. For example, a male astronaut aged 35 has a dose limit of 0.9 Sv. This limit is reached approximately in five years on the ISS so in case of space tourists spending typically 7-10 days on orbit the health risk due to radiation is negligible. Nevertheless, space travel operators need the information in order for customers to give their "informed consent" that they are aware of risks associated with rocketing into the space environment.
In this paper the information on the doses aboard ISS measured by the Pille system and the dose limits of astronauts are summarized. The results of the measurements during the flight of space tourist Charles Simonyi’s are given as well.
- Abstract document
- Manuscript document
IAC-07-A1.9.-A2.7.04.pdf (🔒 authorized access only).
To get the manuscript, please contact IAF Secretariat.