Exposure Experiment of Thermal Control Material for Radiator (ExHAM-Radiator Material Degradation) - 07.11.18

Overview | Description | Applications | Operations | Results | Publications | Imagery

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Science Objectives for Everyone
The Exposure Experiment of Thermal Control Material for Radiator (ExHAM-Radiator Material Degradation) investigates how well heat and radiation-resistant materials can withstand simultaneous exposure to ultraviolet radiation (UV), atomic oxygen (AO), electrons, protons, and other species in the space environment 400 km above Earth. The experiment consists of sample plates mounted with conductive paints, and other materials, that are exposed to the space environment outside the International Space Station over a period of one to three years. The experiment uses an automated photographic apparatus to monitor the samples, which are ultimately returned to Earth-based labs for detailed analysis.
Science Results for Everyone
Information Pending

The following content was provided by Yasuko Shibano, and is maintained in a database by the ISS Program Science Office.
Information provided courtesy of the Japan Aerospace and Exploration Agency (JAXA).
Experiment Details


Principal Investigator(s)
Yasuko Shibano, JAXA/ISAS, Sagamihara, Japan

Information Pending

Tsukuba Space Center, Tsukuba, Ibaraki, Japan

Sponsoring Space Agency
Japan Aerospace Exploration Agency (JAXA)

Sponsoring Organization
Japan Aerospace Exploration Agency

Research Benefits
Scientific Discovery

ISS Expedition Duration
September 2016 - September 2017

Expeditions Assigned

Previous Missions
Information Pending

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Experiment Description

Research Overview

  • In the Exposure Experiment of Thermal Control Material for Radiator (ExHAM-Radiator Material Degradation), electrically conductive white paints, rigid and flexible Optical Solar Reflectors (OSR), and newly developed materials are exposed to the low-Earth orbit environment.
  • While on orbit, the surface of the exposed material is imaged and observed periodically. After completion of the exposure experiment, the samples are returned to Earth and studied in detail in ground-based laboratories.
  • The results of the study can lead to the development of more durable radiator materials for spacecraft thermal control systems for future space missions.

Information Pending

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Space Applications
The ExHAM-Radiator Material Degradation tests paints and other materials that have critical properties necessary for long-term space exploration. Results from these experiments can improve thermal control system performance, which ultimately provides greater protection for lives and equipment in space.

Earth Applications
ExHAM-Radiator Material Degradation establishes performance and constrains failure modes for next-generation thermal materials. Understanding the durability of materials in extreme environments supports their utilization and incorporation into new technologies on Earth. Radiation-resilient materials, for example, can help protect outdoor communication infrastructure and lower the risk of failure during solar events.

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Operational Requirements and Protocols
Sealed bags are launched with each bag containing a sample plate protected by a plastic cover, and a pack of desiccant. The test specimens are mounted on the sample plate. The plastic cover is removed from the sample plate before it is attached on the Handhold Experiment Platform. The plastic cover, the desiccant, and the bag are re-used when returned to Earth. The sample plates are exposed to the space environment for one or two years. Digital imagery, using the high resolution camera on the robot arm, if possible), is taken several times a year. After completion of the exposure phase of the experiment, the samples are removed from the Handhold Experiment Platform, plastic covers are attached, and the samples placed into the storage bags containing the desiccant, and returned to Earth.

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Decadal Survey Recommendations

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Results/More Information

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Related Websites

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