Kibō (ISS module)

Interior of the pressurized module

Astronaut Leland Melvin near the port windows

The Pressurized Module (PM) is the core component connected to the port hatch of Harmony. It is cylindrical in shape and contains twenty-three International Standard Payload Racks (ISPRs), ten of which are dedicated to science experiments while the remaining thirteen are dedicated to Kibō's systems and storage.[3] The racks are placed in a 6-6-6-5 format along the four walls of the module. The end of the PM has an airlock and two window hatches. The exposed facility, experiment logistics module, and remote manipulator system all connect to the PM. It is the location for many of the press conferences that take place on board the station.

Exposed facility

The Exposed Facility (EF), also known as "Terrace", is located outside the port cone of the PM (which is equipped with an airlock). The EF has twelve Exposed Facility Unit (EFU) ports which attach to Payload Interface Unit (PIU) connectors on EF-equipment exchange units (EF-EEUs). All experiment payloads are fully exposed to the space environment. For proper functioning of these experiments, the payload requires an orbital replacement unit (ORU), consisting of the electrical power system (EPS), communications and tracking (CT), and the thermal control system (TCS). Of the twelve ORUs, eight are replaceable by the JEMRMS while the other four are EVA-replaceable.

Experiment logistics module, pressurized section

The experiment logistics module (ELM) includes two sections:

• The pressurized section (ELM-PS), also called the JLP (Japanese logistics pressurized), is a pressurized addition to the PM. It is used as a storage facility, providing storage space for experiment payloads, samples and spare items.[4]
• The unpressurized (external) section (ELM-ES) serves the EF as a storage and transportation module.

The JEM remote manipulator system (JEMRMS) is a 10 m (33 ft) robotic arm, mounted at the port cone of the PM. It is used for servicing the EF and for moving equipment to and from the ELM. The JEMRMS control console was launched while inside the ELM-PS, and the main arm was launched with the PM. The small fine arm, which is 2 m (6 ft 7 in) long and attaches to the end effector of the main arm, was launched aboard HTV-1 on the maiden flight of the HTV spacecraft. Once HTV had docked, the small fine arm was assembled by the crew and deployed outside the airlock to test it. The JEMRMS grappled the arm and unfolded it to flex the joints before stowing it onto the EF.[5] The free end of the JEMRMS is able to use the same type of grapple fixtures that the Canadarm2 uses.[6]

• MAXI – X-ray astronomy from 0.5 to 30 keV.[16] Exposed Facility Slot 1.
• CREAM – Cosmic Ray Energetics and Mass Experiment. Launched on SpaceX CRS-12. Exposed Facility Slot 2.
• OCO-3 – Monitoring of carbon dioxide in the Earth's atmosphere using a flight spare from OCO-2.[17] Exposed Facility Slot 3 port originally held SMILES.
• NREP – Nanoracks External Platform. NREP-2 is the current mission on this pallet. Exposed Facility Slot 4.
• i-SEEP – IVA-replaceable Small Exposed Experiment Platform (JAXA). Mounted to Exposed Facility Slot 5.[18] It is a platform to support small-to-medium (less than 200 kg) payloads. Experiments on the i-SEEP platform are HDTV-EF2 (since 2017), GPSR/Wheel,[19] and SOLISS (since 2019).[20]
• GEDI – Global Ecosystem Dynamics Investigation on ISS Exposed Facility Slot 6 port originally held HREP.
• HISUI – Hyperspectral Imager Suite (METI) replacement for HREP which ended its mission in 2017.[21] Exposed Facility Slot 8 port originally held MCE.
• CALET – CALorimetric Electron Telescope (JAXA), observation for high energy. Launched aboard Kounotori 5 (HTV-5).[22] Mass: 2500 kg.[23] Exposed Facility Slot 9 port originally held SEDA-AP.
• ExHAM 1 and 2 – External Facility Handrail Attach Mechanism (JAXA).[24] Mounted to the deck on handrails in the forward and aft locations next to slots 7 and 10.
• ECOSTRESS – Ecosystem Spaceborne Thermal Radiometer Experiment on Space Station.[25] Exposed Facility Slot 10 port originally held the ELM-ES and the HTV Transfer Pallet.

Deorbited with Kounotori 5 (HTV-5):

• SMILES – Observes and monitors very weak sub-millimeter wave emission lines of trace gas molecules in the stratosphere.[26]
• MCE – Multi-mission Consolidated Equipment (NASA).

Deorbited with SpaceX CRS-15:

• HREP – Hyperspectral Imager for the Coastal Ocean (HICO) and Remote Atmospheric and Ionospheric Detection System (RAIDS) experimental payload.[27]

Deorbited with SpaceX CRS-17:

• CATS – Cloud-Aerosol Transport System (LiDAR, NASA).[28] Originally held in Slot 5, will be replaced by MOLI.

Jettisoned into orbit by ISS robotic arm:[29][30]

• SEDA-AP – Space Environment Data Acquisition equipment-Attached Payload. Measures neutrons, plasma, heavy ions, and high-energy light particles in the station's orbit.
• ICS-EF – Inter-orbit Communication System-Exposed Facility, Japanese communication system. Originally at the Exposed Facility Slot 7.

Japanese:

• RYUTAI Rack – Fluid Physics Experiment Facility (FPEF), Solution Crystallization Observation Facility (SCOF), Protein Crystallization Research Facility (PCRF), Image Processing Unit (IPU)
• SAIBO Rack – Cell Biology Experiment Facility (CBEF), Clean Bench (CB)
• KOBAIRO Rack – Gradient Heating Furnace (GHF)
• MPSR-1 – Multi-Purpose Small payload Rack-1
• MPSR-2 – Multi-Purpose Small payload Rack-2, housing Electrostatic Levitating Furnace (ELF)

American:

• EXPRESS Rack 4 – Biotechnology Specimen Temperature Controller (BSTC), Gas Supply Module (GSM), Space Acceleration Measurement System-II (SAMS-II), Biotechnology Specimen Temperature Controller (BSTC), Nanoracks NanoLab
• EXPRESS Rack 5
• MELFI-1 – two −80° freezer racks
• Life Sciences Glovebox (LSG)

• MOLI – Multi-footprint Observation Lidar and Imager (JAXA) (external)
• JEM-EUSO (internal)