The Japanese H-II Transfer Vehicle-7 (HTV-7), as seen on Sept. 14, 2018, during preparations for its launch.

The Japan Aerospace Exploration Agency (JAXA) unexpectedly delayed a vital cargo launch to the International Space Station just an hour before the rocket was scheduled to lift off.

The agency has not yet provided a new launch date or an explanation for the delay. The mission had already been postponed from a liftoff originally scheduled for Sept. 10 (Sept. 11 local time) by a typhoon near the launch site at Tanegashima Space Center in southern Japan. After the weather delays, the agency calculated a range of launch windows lasting through the end of October.

The vehicle, an H-II Transfer Vehicle called HTV-7, is carrying critical supplies for the six astronauts currently living aboard the orbiting laboratory. The cargo includes six new batteries, which astronauts will install on the exterior of the space station during spacewalks currently scheduled for later this month. The spacecraft is also carrying a host of experiment supplies for the scientific research currently being conducted on the space station.

The launch attempt was scheduled for today at 4:59 p.m. EDT (2059 GMT, 5:59 a.m. local time on Sept. 15). JAXA announced the delay on Twitter about an hour before that time.

After the cargo ship finally takes off, it should take approximately two and a half days to reach the space station. Both the launch and the docking will be broadcast online by NASA TV, with a schedule to be announced pending the new liftoff time.

Email Meghan Bartels at mbartels@space.com or follow her @meghanbartels. Follow us @Spacedotcom, Facebook and Google+. Original article on Space.com.