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COLLOQUIUM
SPEAKER:
Dr G Reitz, Department of Radiation Biology, Institute of
Aerospace Medicine, German Aerospace Center (DLR),
Linder Hoehe, 51147 Koeln, Germany.
DATE & Time:
Tuesday 19 June 2007 at 11:00
VENUE:
Auditorium
TITLE:
Radiation Measurements on the International Space
Station and in Interplanetary Missions
ABSTRACT:
Attached
CONTACT FOR MORE INFORMATION:
Dr Ricky Smit (021 843 1301 or smit@tlabs.ac.za)
Radiation Measurements on the International Space Station
and in Interplanetary Missions
G. Reitz
Department of Radiation Biology, Institute of Aerospace Medicine, German Aerospace
Center (DLR), Linder Hoehe, 51147 Koeln, Germany.
For area monitoring several active and passive dosemeters in the frame of the DosMap
experiment were flown as part of NASA's Human Research Facility in Increment 2 of
the ISS. This was the first time a mapping of the radiation distribution inside the US lab
and Node 1 could be provided. Further measurements inside the ISS are planned with
the experiment DOSIS using similar instrumentation. To relate these quantities to
radiation protection quantities measurements needs to be performed using
anthropomorphic phantoms. The ESA multi-user facility MATROSHKA was designed to
provide accurate information on the radiation doses in human organs during EVA and
IVA activities. The key part of MATROSHKA is a human phantom upper torso,
equipped with numerous radiation detectors at the surface and inside the phantom. The
MATROSHKA facility therefore allows the determination of the empirical relations
between measurable absorbed doses at the skin and the tissue absorbed doses in
different depth inside the phantom. Once the ratios for the tissue- and surface
absorbed doses are known for a given radiation field around the human body, these
values may be used in future exposures during long haul space flights e.g. a flight to
Mars to determine the required tissue absorbed doses from measurements of surface
absorbed doses.
For future manned missions to Mars actual measurements needs to be provided in
precursor missions, since until now only approximate dose values from model
calculation are obtainable. To characterize the radiation environment on the cruise to
Mars and on its surface two instruments are planned, one as part of the NASA MSL
(Mars Science Lab) mission, the Radiation assessment detector (RAD) and one as part
of the European ExoMars mission, the Ionizing Radiation Sensor (IRAS). Both
instruments are silicon detector telescopes using scintillators with anti coincidence
techniques; RAD in addition uses a CsI calorimeter.
This presentation intends to give a short overview of the instrumentation used in the
DosMap experiment and inside the MATROSHAKA facility together with selected
results and finally describes the instruments and the measurements planned in the near
future on ISS and on missions to Mars.
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