Fact Sheet

Text Size

Scientists and payload developers can get more information on International Space Station research facilities by contacting the ISS Payloads Office or at 281-244-6187.

Japanese Experiment Module - Exposed Facility (JEM-EF)


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

Facility Overview

This content was provided by Wakabayashi Yasufumi, and is maintained in a database by the ISS Program Science Office.

Brief Facility Summary

Japanese Experiment Module - Exposed Facility (JEM-EF) is an external platform that can hold up to 10 experiment payloads at a time outside Kibo. The first JAXA instruments are SEDA-AP (Space Environment Data Acquisition Equipment-Attached Payload) and MAXI (Monitor of All-sky X-ray Image). The first NASA instruments will be a hyperspectral imager and an ionosphere detector.

Facility Manager(s)

  • Wakabayashi Yasufumi, Japan Aerospace Exploration Agency (JAXA), Tsukuba-shi, Japan
  • Co-Facility Manager(s)

  • , Japan Aerospace Exploration Agency (JAXA), Tsukuba-shi, Japan
  • Facility Developer(s)

    Japan Aerospace Exploration Agency (JAXA), Tsukuba, , Japan

    Sponsoring Agency

    Japan Aerospace Exploration Agency (JAXA)

    Expeditions Assigned


    Previous ISS Missions

    The JEM-EF will be transported to the ISS with the JEM on STS-122(2J/A) in March 2009.

    ^ back to top

    Facility Description

    Facility Overview

    • The Japanese Experiment Module - Exposed Facility (JEM-EF) will be utilized by Japan Aerospace and Exploration Agency (JAXA) for experiments. The facility may be available for use by all international partners involved in the International Space Station (ISS).

    • The payload interface for the JEM-EF is the Exposed Facility Unit (EFU). There are 12 EFUs on the JEM-EF, 8 of which are available for users. The other three are used for temporary storages and JEM/JEM EF Inter-orbit Communication System (ICS).

    • JEM-EF is expected to contribute to the evolution of science and technology and promote international cooperation.


    The Japanese Experiment Module - Exposed Facility (JEM-EF) is a unique platform on the ISS that is located outside of the Japanese Experiment module (JEM), Kibo (Hope) and is continuously exposed to the space environment. Astronauts exchange payloads/payload facilities from the Kibo through the scientific airlock using the Kibo Remote Manipulator System. Payloads/payload facilities positioned on the exterior platform focus on Earth observation, as well as, communication, scientific, engineering and materials science experiments.

    The JEM-EF can hold up to 9 experiment payloads at a time; it measures 5.6 m x 5 m x 4 m with a mass of approximately 4000 kg. JEM-EF will be operated for approximately ten years on orbit supporting exposed experiments. It will supply electrical power, circulate coolant and collect payload/payload facilities data. Standard payload/payload facility size for the JEM-EF is 1.85 m x 1.0 m x 0.8 m with a mass of 500 kg including all payload accommodations.

    JEM-EF provides utilities, including two channels of 120Vdc power supply for payload normal operation; the wire size for each channel can provide up to 3KW. The survival power supply to each payload is 100W and is provided separately. Payload commands can be processed via standard MIL-STD-1553B data line to each location. Two Ethernet connections are available at payload locations #1, #5, #2 and #6. High rate fiber-optical downlink and active cooling is provided to each payload location. Additional analog lines are available at each payload location to process payload housekeeping data for temperature and pressure. A data line which meets NTSC (image/synchronization control) specification is available at each payload location to process payload video system data.

    The JEM-EF consists of several components:

    • Small Fine Arm (SFA) is the secondary arm which will be attached to the end of JEM - Remote Manipulator System (JEM-RMS), primary arm. The SFA is used for fine manipulation tasks and will be stowed on the JEM-EF when not in use. The JEM-RMS is used to exchange payload/payload facility units.

    • JEM-EF Camera and Light consists of a TV camera, a light and a pan/tilt unit. This component gives a view of payloads/payload facilities when they are being exchanged by the JEM-RMS.

    • Equipment Exchange Unit (EEU) is a mechanism on JEM EF which connects the Payload Interface Unit (PIU) on payload to the JEM-EF. All utilities are provided through this interface from JEM EF to payload.

    ^ back to top


    Facility Operations

    The JEM-EF will be transported to the ISS with the JEM on STS-122(2J/A) in March 2009. JEM-EF payloads and payload facilities will be transported to and from orbit using an ISS program-supplied carrier. Once the carrier is docked, the payload/payload facility will be maneuvered by the robotic manipulators of the ISS to its final operational location on the JEM-EF. At the end of its operational phase, a payload will be transported to the carrier by robotic means and then returned to ground for post-mission inspection and analysis and, possibly, refurbishment.

    ^ back to top

    Results/More Information

    Information Pending

    ^ back to top


  • Onboard ISS
  • ^ back to top

    Results Publications

    ^ back to top

    Ground Based Results Publications

    ^ back to top

    ISS Patents

    ^ back to top

    Related Publications

    ^ back to top

    Related Websites
  • Kibo - Japanese Experiment Module
  • ^ back to top


    image The JEM-EF flight unit under construction at the JAXA facility in Tsukuba, Japan. The JEM-EF provides payloads with electrical power, data, and active thermal control. Image courtesy of JAXA.
    + View Larger Image

    image Computer generated image of the completed International Space Station with external workstations. Image courtesy of NASA.
    + View Larger Image

    Information provided by the investigation team to the ISS Program Scientist's Office.
    If updates are needed to the summary please contact JSC-ISS-Program-Science-Group. For other general questions regarding space station research and technology, please feel free to call our help line at 281-244-6187 or e-mail at JSC-ISS-Payloads-Helpline.