Radiation dosimetry on board the International Space Station (ISS) is very important for investigating biological effects in a space radiation environment. The radiation environment of the ISS varies complexly depending on the stage of the solar activity cycles, the occurrence of large solar flares, and shielding conditions (i.e., walls of the ISS and its contents, such as payload racks). The radiation dose inside the ISS is thus greatly influenced by the radiation environment. Therefore, by installing area dosimeters at fixed locations inside the Japanese Experiment Module Kibo, JAXA performs continuous area radiation monitoring throughout the ISS Kibo program. Area PADLES is the series program to perform area radiation monitoring in Kibo. The first Area PADLES started on 1 June 2008 during Increment 17 just after Japanese Pressurized Module (JPM) attachment to the ISS operations. 17 area dosimeters in fixed locations on JPM and the Experiment Logistics Module-Pressurized Section (ELM-PS) are replaced every 6 months or every increment. In increment 25/26 17area dosimeters for #4 Area PADLES were recovered from JPM and new 17 ones for #5Area PADLES have been launched and installed inside Kibo by Space Shuttle Mission STS-133/ULF5.Principal Investigator(s)
Japan Aerospace Exploration Agency (JAXA), Tsukuba, , Japan
Japan Aerospace Exploration Agency (JAXA)Sponsoring Organization
Information PendingResearch Benefits
Information PendingISS Expedition Duration:
September 2010 - September 2014Expeditions Assigned
25/26,27/28,29/30,31/32,33/34,35/36,37/38,39/40Previous ISS Missions
From Increment 17, five experiments using the PADLES system started in 2008: area radiation monitoring in Kibo (Area PADLES); dose measurements of biological samples exposed to space radiation (Bio PADLES); personal radiation dosimetry for Asian astronauts (Crew PADLES); various kinds of international cooperative experiments with ISS partners, such as the Matroshka project conducted by the German Aerospace Center in Cologne, and the ALTCRISS project conducted by the National Institute of Nuclear Physics (Dosimetric PADLES); and measurement of the directional dependence of radiation doses inside the Kibo module (Exp PADLES). Past Area PADLES schedule are shown as follows:
Area PADLES #1: Jun 1 2008 to Mar 29 2009 over Increment 17-18,
Area PADLES #2: Mar 16 2008 to Sep 12 2009 over Increment 18-19,
Area PADLES #3: Aug 29 2009 to Apr 18 2010 over Increment 19-22,
Area PADLES #4: Apr 5 2010 Aug 29 2009 to Mar 9 2011 over Increment 23-26,
Area PADLES #5: Apr 5 2011 Aug 29 2009 to May 22 2011 over Increment 26-27,
Area PADLES #6: June to Nobember 2011 over Increment 28-29 (Planed),
Area PADLES #7: December 2011 to May 2012 over Increment 30-31 (Planed),
Area PADLES #8: June to Nobemver 2012 over Increment 32-33 (Planned).
Area PADLES #9: September 2012 to March 2013 over increment 33-34.
JAXA Area PADLES dosimeter consists of seventeen area dosimeters and the pieces of Velcro, each of which is labeled with the deployment location on the wall inside the JPM and JLP.
They are fixed to Kibo walls with tape and the tether of their casing holder. The Area PADLES holder size is 4.6 cm(w) , 4.6 cm(l) , 9 cm(t) and the weight is 24g. These are assembled and analyzed by the PADLES Group on JAXA TKSC. In the PADLES system, the CR-39 PNTDs measure space-radiation fluence as a function of LET in a LET range above 10keV/um, while the TLDs measure absorbed doses of low LET radiation (less than 10keV/um). These data can be read only after they return to Earth. A series of programs named AUTO PADLES was also developed for the rapid and systematic analysis of the PADLES dosimeters. The package preparation and method for calculating the total absorbed dose, dose equivalent, and mean quality factor over an entire LET range were described in previous papers listed in Section Publications.
Information PendingEarth Applications
The dosimetry technique has already used for dose management of radiation worker in high enery accelelation. The high-speed microscope scaning image technique are used for diagnostic cytology of cancer.
Mentioned above article about Unique investigation constraints. Since dosimeters can be analyzed in a terrestrial laboratory (JAXA TKSC), so dosimeters return must be needed. No observation and downlink aren't needed during measurement.Operational Protocols
Ttwo task are needed, Area PADLES Installation and Removal.
NASA Image: ISS028E007155 - Expedition 28 Flight Engineer Satoshi Furukawa posing for a photo with Matroshka-R PADLES (Passive Dosimeter for Lifescience Experiment in Space) Area Dosimeters int the Service Module (SM).