NEW YORK — Japan’s first unmanned spacecraft to haul cargo to the international space station (ISS) is nearly ready for its maiden launch.

The cargo ship is poised to launch toward the station Sept. 10 from the Tanegashima Space Center in southern Japan on a shakedown cruise. If all goes well, the inaugural spacecraft, called the H-2 Transfer Vehicle 1 (HTV-1), should arrive at the station on Sept. 17.

The spacecraft was built by the Japan Aerospace Exploration Agency (JAXA) and will launch atop the country’s brand new H-2B rocket.

“JAXA is ready to carry out the important HTV-1 mission as a new contribution to the ISS program,”  Masazumi Miyake, a JAXA director detailed to NASA’s Johnson Space Center in Houston, said during  a Sept. 2  briefing.

JAXA mission managers were expected to hold a series of final readiness reviews for HTV-1 and its rocket booster between Sept. 3 and launch day.

“There’s very little work to be done,” said Mike Suffredini, NASA’s space station program manager. “We’re all on schedule and we’re not working any issues relative to this launch.”

 Suffredini said the new spacecraft, like cargo ships built by Europe and Russia, will be vital to supporting the space station’s six-person crew once NASA’s space shuttle fleet retires in the next year or so.

The HTV-1 cargo ship is Japan’s latest contribution to the international space station. Astronauts completed construction of JAXA’s enormous Kibo laboratory, a $1 billion facility the size of a tour bus, in July with the addition of an exterior experiment porch.

The spacecraft is a solar-powered cylinder about 10 meters long and 4.4 meters wide. It can haul up to 6 tons of pressurized and unpressurized cargo to the station, but will only be packed with about 3.5 tons for its debut flight.

Unlike the automated cargo ships built by Russia and Europe, which can dock themselves at the station, the HTV-1 is designed to fly close to the orbiting laboratory and be grabbed by its robotic arm. Astronauts inside the outpost will monitor the approach and rendezvous.

Miyake said JAXA has spent about $680 million since 1997 to develop the HTV spacecraft.

The new H-2B rocket launching the HTV-1 cargo ship is a more powerful booster derived from Japan’s workhorse H-2A rocket, which the country has been flying since 2001.

The HTV spacecraft will be controlled from JAXA’s Tsukuba Space Center, which is also home to the agency’s Kibo mission control center.

Japan has until Sept. 30 to try and loft the HTV-1 mission from its seaside launch site before its window closes due to the country’s off-shore fishing season. The next opportunity to launch the spacecraft after September is in February 2010, Suffredini said.