Kounotori 9 (こうのとり9号機), 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).[4][5] It was launched on 20 May 2020, at 17:31:00 UTC.[6]
Kounotori 9 is the last HTV of the original model, with following missions replaced with the HTV-X.[4][7]
Spacecraft
Major difference from the previous Kounotori are:[8]
Camera assembly unit and Wireless LAN communication unit (WLD), described below.
Wireless LAN Demonstration
Wireless LAN Demonstration, or WLD (pronounced wild)[8] is an experiment that will be performed during Kounotori 9's flight. During the test, a video taken by Kounotori 9 will be broadcast in real time on board the space station, via a wireless LAN (WLAN) datalink.[9] The experiment will be conducting during Kounotori 9's approach, departure, and while berthed to the ISS.[10] For WLD, the spacecraft has a camera attached to its propulsion module, while a data processor and WLAN antenna is located at the Unpressurized Logistics Carrier's aperture.[8] The technology to be tested by WLD will enable ISS crews to monitor approaching vehicles during an autonomous docking.[11] According to JAXA, if successful this will be the first time for two spacecraft to communicate using WLAN during a rendezvous.[8]
Cargo
Kounotori 9 carried about 6200 kg of cargo mass, consisting of 4300 kg in the pressurized compartment and 1900 kg in the unpressurized compartment.[8] In addition to food items and crew commodities, the pressurized compartment (Pressurized Logistics Carrier; PLC)'s cargo consists of:[8]
JAXA cargo:
Solid Combustion Experiment Module (SCEM)
Integrated Standard Imager for Microsatellites (iSIM), a commercial technology demonstration payload by Satlantis
Equipment for the space media business collaboration (Space Frontier Studio KIBO)
On departure from ISS, Kounotori 9 was loaded with the Exposed Pallet of Kounotori 8 (EP8) carrying the replaced nickel-hydrogen batteries. It was left on ISS due to the missed extravehicular activity during the Kounotori 7 mission for the launch failure of Soyuz MS-10 in 2018. The Exposed Pallet of Kounotori 9 (EP9) was left on ISS, and subsequently, it was disposed of by jettisoning into orbit on 11 March 2021 using Space Station Remote Manipulator System (SSRMS), carrying old nickel-hydrogen batteries.[1][12]
The Exposed Pallet of Kounotori 9 (EP9) reentered to Earth atmosphere on 8 March 2024. An object from this cargo survived the reentry, damaged a house in Naples, Florida.[13][14]
Operations
Launch
Kounotori 9 was launched aboard the ninth and final launch of H-IIB rocket on 20 May 2020, at 17:31:00 UTC.[2] The launch took place amid the COVID-19 pandemic, so that the usual launch viewing places were closed to spectators, and the local town offices requested not to visit for launch observation.[15]
After the successful launch, the Kounotori 9 arrived to the proximity of the International Space Station on 25 May 2020, and it was captured by SSRMS at 12:13 UTC.[16] It was mated to the Harmony's Common Berthing Mechanism (CBM). Berthing operation completed at 18:25 UTC.[17]
Operation while berthed to ISS
ISS crew opened the hatch of the Kounotori's PLC, and entered at 19:24 UTC.[18] Cargo transfer of the pressurized cargo by the crew began on 26 May 2020.[19]
Exposed Pallet (EP9), which carries lithium-ion batteries, was extracted from the ULC by the ground-operated SSRMS on 1 June 2020.[20] Then, Kounotori 8's Exposed Pallet (EP8), carrying old nickel-hydrogen batteries, was stowed into the ULC on 02:48 UTC, 2 June 2020.[21]
Departure and reentry to the Earth atmosphere
On 18 August 2020, Kounotori 9 was detached from Harmony's CBM by the SSRMS, and it was released into orbit at 17:36 UTC. It was disposed by the destructive reentry to the Earth atmosphere at around 07:07 UTC, on 20 August 2020.
Launches are separated by dots ( • ), payloads by commas ( , ), multiple names for the same satellite by slashes ( / ). Crewed flights are underlined. Launch failures are marked with the † sign. Payloads deployed from other spacecraft are (enclosed in parentheses).