Japan's first unmanned space freighter reached the International Space Station Sept. 17, marking another milestone in international space cooperation. Hovering approximately 30 feet away from the ISS, the Japanese cargo pod was grasped by a Canadian-built robotic arm with European and American astronauts at controls. The entire operation was overseen by a Russian commander.
"It's really true international cooperation," European astronaut Frank De Winne said.
The Japanese H-II HTV (Transfer Vehicle) launched Sept. 10 from the Tanegashima Space Center in southern Japan. While other automated freighters from Europe and Russia have been used to re-supply the space station, the Japanese spacecraft is first to arrive with both pressurized and unpressurized cargo.
The freighter's unpressurized cargo bay includes a NASA experiment aimed at mapping the upper atmosphere and a Japanese experiment to study the effects of trace gases on the ozone layer. Both will be loaded on the newly installed external porch of the space station's Kibo lab module.
The 23,000-pound, $217 million unmanned spacecraft will stay at the space station for about a month before being detached and sent to a fiery death as it enters the earth's atmosphere.
In addition to hauling both pressurized and unpressurized cargo, the HTV also differs from European and Russian models by not directly docking with the ISS. After grabbing the pod with one of the space station's robotic arms, the HTV was pulled to the vehicle and bolted in place with 16 motorized bolts.
The use of unmanned spacecraft to re-supply the station is considered critical to the future of the ISS, particularly with the United States currently scheduled to end the space shuttle program at the end of next year. While developing new rockets to reach deeper into space than the low orbit space station, NASA plans to hitch rides with the Russians for missions to the ISS.