Dose Distribution Inside ISS - Dosimetry for Biological Experiments in Space (DOSIS-DOBIES) - 10.21.14
ISS Science for Everyone
Science Objectives for Everyone
The Dose Distribution Inside ISS - Dosimetry for Biological Experiments in Space (DOSIS-DOBIES) provides documentation of the actual nature and distribution of the radiation field inside the ISS and develops a standard method to measure the absorbed doses in biological samples onboard the ISS.
Science Results for Everyone
I’ll see your radiation dose and double it. Two active and two passive radiation detectors collected data from different locations in the space station. Data from the passive detectors were analyzed on the ground while monthly downlinks collected data from the active detectors. The passive thermoluminescence detectors (TLD) yielded data on daily dose rate measured with both neutron sensitive 6LiF and non-neutron sensitive 7LiF. The data showed that the absorbed dose rate inside the Columbus module can vary up to 50 percent depending on location.
European Space Agency (ESA), Noordwijk, , Netherlands
German Aerospace Center (DLR), Cologne, , Germany
Sponsoring Space Agency
European Space Agency (ESA)
ISS Expedition Duration
March 2009 - September 2011
Previous ISS Missions
DOSIS-DOBIES first began operations on ISS Expedition 18.
- DOSIS will use both passive and active radiation measurement devices to measure the radiation environment inside of the Columbus module.
- DOBIES will study the responses of different detector types in space radiation fields. This will lead to a unique recommendation and description on dosimetric systems for radiobiologocal experiments in space.
- A total number of 64 measurement positions are allocated to the DOSIS-DOBIES investigations.
Dose Distribution inside ISS (DOSIS): The proposed experiment will provide documentation of the actual nature and distribution of the radiation field inside the spacecraft. Integral measurements of energy, charge and LET spectra of the heavy ion component will be done by the use of different nuclear track detectors. TLDs deliver mission averaged absorbed doses. Different neutron dosimeters allow for measurement of the neutron dose.
Dosimetry for Biological Experiments in Space (DOBIES): The objective of this project is to develop a standard Dosimetric method (as a combination of different techniques) to measure the absorbed doses and equivalent doses in biological samples, as a contribution to DOSIS in EPM and COL, and EXPOSE-E and EXPOSE-R payloads.
DOSIS-DOBIES will consist of active radiation detectors: two DOSTEL silicon detectors, Alteino, tissue equivalent proportional counter (TEPC), Pille thermoluminescent detector (TLD) reader, passive radiation monitoring instruments and nuclear track detector packages (NTDP).
The results of the radiation absorption data collection carried out in 2006 aboard the Columbus module on the ISS showed that the radiation environment is very complex and requires multiple types of passive detectors to create a complete picture of the LET and Tracked Etched Detectors TED contributions to absorbed dosage. Both Thermoluminescence TL and Optically Stimulated Luminescence OSL detectors were used for low LET radiation and TED for High LET radiation in order to create a characteristic profile of absorbed radiation. The observed dose rates inside the Columbus varied as much as 50% depending upon locations. Doses of LET particles obtained using TLDs on the ground and in space both were consistent in showing up to 10% in uncertainty. It is believed that some of the uncertainties involved with the TED results is a factor of different detection thresholds and readout methods for the different materials. A more detailed comparison between different lab and ground based experiments is needed. (Vanhavere 2008)
Ground Based Results Publications
Bilski P, Berger T, Hajek M, Hajek M, Twardak A, Koerner C, Reitz G. Thermoluminescence fading studies: Implications for long-duration space measurements in Low Earth Orbit. Radiation Measurements. 2013 September; 56: 303-306.
NASA Image: ISS015E12110 - View of the Tissue Equivalent Proportional Counter (TEPC) Radiation Detector (gold cylinder) and the TEPC Spectrometer (gold box) in the U.S. Laboratory, Destiny during Expedition 15. The TEPC will be one of several radiation measurement devices used for DOSIS-BOBIES.
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