Matroshka experiments

Matryoshka, Eng. Matroshka (after the eponymous Russian wooden dolls), is the name of an experiment of the European Space Agency (ESA ) and the German Aerospace Center (DLR ) for the measurement of radiation exposure for a human being on the International Space Station (ISS ) at 300 km altitude.

Matryoshka is a structured into separable slices Phantom of human greatness, the components of a similar beam interaction point as the organs of a human being. It 68 kg, 1.1 m high and has a diameter of 60 cm. It contains real human bones and plastics that mimic the absorption behavior of human organs. Recessed in the disks are approximately 600 sensors. A carbon fiber outer structure encasing the Phantom and a constant oxygen atmosphere.

The Matryoshka doll was transported on 24 January 2004 with a Progress spacecraft to the ISS and installed on March 15, 2004 to August 18, 2005 outside the ISS, in order to measure the radiation exposure (MRT -1). December 2005 put it away (MTR -2), the measurements inside the ISS. The Phantom 2009 returned back to Earth.

Due to the combination of different particle and photon radiation with different energy and linear energy transfer ( LET) is the dosimetry in space difficult; the body is not loaded homogeneously. The Matryoshka phantom was outside the station 0.9 mGy / d on the surface ( skin) and 0.2-0.4 mGy / d in the range of the deeper organs. The equivalent dose was 1.3 mSv / d outside the station and about 0.5 mSv / d within; to a large extent the exposure arose during the passage times through the South Atlantic anomaly. For comparison, the natural background radiation on Earth's surface in Germany is about 0.006 mSv / d