, also known as HTV-8 was the 8th flight of the
H-II Transfer Vehicle, a robotic cargo spacecraft to resupply the
International Space Station
The International Space Station (ISS) is the largest modular space station currently in low Earth orbit. It is a multinational collaborative project involving five participating space agencies: NASA (United States), Roscosmos (Russia), JAXA ( ...
. It was launched on 24 September 2019, 16:05:05 UTC.
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]
Spacecraft
Major changes from previous Kounotori are:[
* Replacement of Earth sensor with ]star tracker
A star tracker is an optical device that measures the positions of stars using photocells or a camera.
As the positions of many stars have been measured by astronomers to a high degree of accuracy, a star tracker on a satellite or spacecraft may ...
for spacecraft attitude control
Attitude control is the process of controlling the orientation of an aerospace vehicle with respect to an inertial frame of reference or another entity such as the celestial sphere, certain fields, and nearby objects, etc.
Controlling vehicle ...
* New cargo racks developed for HTV-X
, tentatively called HTV-X, is an uncrewed expendable cargo spacecraft under development by Japan Aerospace Exploration Agency ( JAXA) as the successor of H-II Transfer Vehicle (HTV). the first flight is planned to be launched in January 202 ...
which allows 30% more Cargo Transfer Bags (CTB) to be carried in the Pressurized Logistics Carrier (PLC). (316 CTBs for Kounotori 8, compared to 248 CTBs of Kounotori 6)
Cargo
Kounotori 8 carries about 5300 kg of cargo, consisting of 3400 kg in the pressurized compartment and 1900 kg in the unpressurized compartment.[
Cargo in the Pressurized Logistics Carrier (PLC) include:][
* JAXA experiment Cell Biology Experiment Facility-Left (CBEF-L)
* JAXA experiment Sony Optical Link for ISS (SOLISS), a satellite optical communication demonstration co-developed with
* JAXA experiment Hourglass, which will investigate the behavior of soil and rock particles under low gravity conditions
* Gas bottle for JAXA experiment
* Experiment materials for Electrostatic Levitation Furnace (ELF)
* ]CubeSat
A CubeSat is a class of miniaturized satellite based around a form factor consisting of cubes. CubeSats have a mass of no more than per unit, and often use commercial off-the-shelf (COTS) components for their electronics and structure. CubeSats ...
s to be deployed from ISS: NARSSCube-1, AQT-D, RWASAT-1
* NASA system supply cargo: new water tank for Water Storage System (WSS)
* NASA system supply cargo: tank for Nitrogen Oxygen Recharge System (NORS)
In the Unpressurized Logistics Carrier (ULC), Kounotori 8 carries six lithium-ion batteries Orbital Replacement Units (ORUs) for replacing the ISS's existing nickel-hydrogen batteries. The transportation of replacement batteries is a continuation from the previous Kounotori 6 and 7, and will continue through to Kounotori 9
, also known as HTV-9 was the 9th flight of the H-II Transfer Vehicle, a robotic cargo spacecraft to resupply the International Space Station (ISS). It was launched on 20 May 2020, at 17:31:00 UTC.
Kounotori 9 is the last HTV of the original ...
.[
]
Operation
Launch
The H-IIB
H-IIB (H2B) was an expendable space launch system jointly developed by the Japanese government's space agency JAXA and Mitsubishi Heavy Industries. It was used to launch the H-II Transfer Vehicle (HTV, or ''Kōnotori'') cargo spacecraft for ...
launch vehicle carrying Kounotori 8 was initially scheduled to be launched at 21:33:29 UTC, 10 September 2019. During launch preparation, a fire broke out at the launch pad at around 18:05 UTC (T minus 3.5 hours), and the launch was called off. The cause of fire was attributed to the static electricity on the heat resistant material under the mixture of liquid oxygen and gas oxygen for the engine pre-cooling.[ but the collision avoidance check revealed that the 2nd stage of the launch vehicle might approach near the ]Soyuz MS-15
Soyuz MS-15 was a Soyuz spaceflight launched on 25 September 2019, transporting two members of the Expedition 61 crew and a short duration visiting crew member to the International Space Station. Soyuz MS-15 was the 143rd flight of a Soyuz spac ...
which was scheduled to be launched on 25 September 2019. A revised launch schedule was set for 16:05 UTC, 24 September 2019. On 24 September 2019, 16:05:05 UTC, the Kounotori 8 aboard H-IIB was launched successfully.[
]
Operation while berthed to the ISS
Kounotori 8 was captured by the Space Station Remote Manipulator System (SSRMS) at 23:13 UTC, on 27 September 2019, and berthed at Harmony's nadir
The nadir (, ; ar, نظير, naẓīr, counterpart) is the direction pointing directly ''below'' a particular location; that is, it is one of two vertical directions at a specified location, orthogonal to a horizontal flat surface.
The direc ...
Common Berthing Mechanism
The Common Mechanism (CBM) connects habitable elements in the US Orbital Segment (USOS) of the International Space Station (ISS). The CBM has two distinct sides that, once mated, form a cylindrical vestibule between modules. The vestibule is ...
(CBM) by 17:55 UTC, on 28 September 2019.
The External Palette (EP8), which carries the lithium-ion battery
A lithium-ion or Li-ion battery is a type of rechargeable battery which uses the reversible reduction of lithium ions to store energy. It is the predominant battery type used in portable consumer electronics and electric vehicles. It also s ...
Orbital Replacement Unit
Orbital replacement units (or on-orbit replaceable unit) (ORUs) are key elements of the International Space Station that can be readily replaced when the unit either passes its design life or fails. ORUs are parts of the main systems and subsystems ...
s (ORU), was extracted from the Kounotori 8's Unpressurized Logistics Carrier (ULC) by the SSRMS (Canadarm2) on 29 September 2019.
The External Palette of Kounotori 7 (EP7) was placed in the Kounotori 8's ULC. EP7 was left on the ISS after the departure of Kounotori 7 due to the schedule change of extravehicular activity
Extravehicular activity (EVA) is any activity done by an astronaut in outer space outside a spacecraft. In the absence of a breathable Earthlike atmosphere, the astronaut is completely reliant on a space suit for environmental support. EVA inc ...
after the launch failure of Soyuz MS-10
Soyuz MS-10 was a crewed Soyuz MS spaceflight that aborted shortly after launch on 11 October 2018 due to a failure of the Soyuz-FG launch vehicle boosters. MS-10 was the 139th flight of a Soyuz spacecraft. It was intended to transport two me ...
.
Departure and reentry to the Earth atmosphere
On 1 November 2019, Kounotori 8 was detached from Harmony's CBM by the SSRMS (Canadarm2), and it was released into orbit at 17:20 UTC.
It was disposed by the destructive reentry to the Earth atmosphere
The atmosphere of Earth is the layer of gases, known collectively as air, retained by Earth's gravity that surrounds the planet and forms its planetary atmosphere. The atmosphere of Earth protects life on Earth by creating pressure allowing for ...
at around 02:09 UTC, on 3 November 2019.
References
External links
JAXA HTV page
{{Orbital launches in 2019
H-II Transfer Vehicles
2019 in Japan
Spacecraft launched in 2019
Spacecraft which reentered in 2019