HTV-X Arrives at ISS For the First Time
After its launch from the Yoshinobu Launch Complex at the JAXA Tanegashima Space Center on October 26th at 9:00 AM JST, Japan’s HTV-X1 resupply mission arrived at the ISS, where it was berthed at roughly 1:00 AM JST on October 30th. The HTV-X spacecraft is now, at time of publishing, berthed to the nadir port of the station’s Columbus module. During the capture process, Japanese Astronaut Kimiya Yui operated the station’s Canadarm2, to capture and guide the vehicle to its intended position. Astronauts opened the hatch to the HTV-X spacecraft to begin offloading supplies later that same day.
This is the first flight of the HTV-X spacecraft, the successor to Japan’s H-II Transfer Vehicle (HTV) which flew nine resupply flights to the ISS between 2009 and 2020. The spacecraft’s primary role in service of the space station is delivering experimental payloads for the Japanese Experiment Module, Kibō (also “JEM”), the largest of ISS’ pressurized modules. The HTV-X Spacecraft can carry nearly 9,000 lb of internal cargo, and up to 3,000 lb of externally mounted cargo.
HTV-X1, as a test flight of the vehicle, did not utilize the full cargo capacity of the design, carrying only minimal external payload. Among the deliveries to the ISS was the Demonstration System for CO₂ Removal (DRCS). DRCS is a carbon removal system for maintaining atmosphere conditions inside pressurized spacecraft, and is a pathfinder for future systems that JAXA aims to provide in service of the Lunar Gateway and Artemis’ Pressurized Rover. HTV-X1 also carried consumable supplies such as food and water for the station’s crew. HTV-X1’s food supply included fresh produce such as apples and pears, a delivery which was enabled in part by the spacecraft’s late cargo access capability.
The vehicle launched aboard Japan’s new flagship launch vehicle, the H3 rocket, on its seventh flight. H3 and HTV-X are the latest capabilities Japan has added to its civil space program as the nation seeks to expand its participation in international aerospace efforts such as NASA’s Artemis Program alongside its own domestic capabilities. In service of Artemis, an upgraded version of the HTV-X spacecraft is anticipated to resupply NASA’s Lunar Gateway under the Gateway Logistics Services program.
HTV-X follows other new additions to the broader capabilities of the International Space Station’s service fleet. In September, SpaceX demonstrated a new capability for the cargo variant of the company’s Dragon 2 spacecraft, which allows it to reboost the station’s orbit in conjunction with Russian Progress cargo vehicles. And prior to the launch of HTV-X1, Northrop Grumman’s Cygnus spacecraft was berthed at the same port, debuting its new XL configuration which allows the vehicle to carry an increased cargo payload.
Before its departure from the International Space Station, as with many visiting cargo ships, HTV-X will be loaded with waste products from the ISS for disposal purposes. However, the HTV-X1 mission will not be over yet, as the spacecraft is expected to perform a three month free-flying mission wherein it will deploy small satellites and perform laser-based altimetry observations.
