HAMLET—Human Model MATROSHKA for Radiation Exposure Determination of Astronauts

Kurzfassung

The exploration of space as seen in specific projects from the European Space Agency (ESA) for example, the search for life on Mars (ExoMars), acts as groundwork for human long duration space missions. One of the main constraints for long duration human missions, besides the psychological factors and the impact of microgravity on the human physiological system, is radiation. The radiation load on astronauts and cosmonauts in space (as for the ISS) is a factor of ~ 100 higher than the natural radiation on earth. This radiation load will further increase should humans travel to Mars. In preparation for long duration space missions it is important to evaluate the impact of space radiation in order to secure the safety of the astronauts and minimize their radiation risks. To determine the radiation risk on humans one has to measure the radiation doses to radiosensitive organs within the human body. One way to approach this is the European Space Agency’s (ESA) facility MATROSHKA (MTR) under the scientific and project lead of DLR. It is dedicated to determine the radiation load on astronauts within and outside the International Space Station (ISS), and was launched in January 2004. MTR is currently in its fourth experimental phase. MTR, which mimics a human head and torso, is an anthropomorphic phantom containing over 6,000 radiation detectors to determine the depth dose and organ dose distribution in the body. It is the largest international research initiative ever performed in the field of space dosimetry and combines the expertise of leading research institutions around the world. It consequently generates a huge pool of data of potentially immense value for research. Aiming at optimal scientific exploitation, the collaborative project HAMLET is bringing together a European expert committee, consisting exclusively of members of the MTR consortium, to process and compile the data acquired individually by the participating laboratories. Based on experimental input as well as on radiation transport calculations, a three-dimensional model for the distribution of radiation dose in an astronaut’s body will be built up. The results will describe the exposure conditions both for extra-vehicular activities (MTR-1, 2004–2005) and inside the ISS (MTR-2A/B/KIBO, 2006–20010). The scientific achievements contribute essentially to radiation risk estimations for future interplanetary space exploration by humans, putting them on a solid experimental and theoretical basis. Maximum public outreach is assured by making the carefully processed data and related reports directly available to the scientific community and the public via a web-based database. The HAMLET project is funded by the European Commission under the EU´s Seventh Framework Programme (FP7) under Project Nr: 218817 and coordinated by the German Aerospace Center (DLR) http://www-fp7-hamlet.eu