Japan’s new space truck

There's been a lot of fretting in space policy circles about the launch "gap" after the U.S. space shuttle retires, and how NASA will manage to ferry astronauts to the space station when it has no space vehicle of its own. Equally important is how cargo will be delivered. Now that six people are living on the station and it's finally open for business as a research laboratory, the crew needs lots of equipment, food and other stuff. Tons of it, in fact.

Which is why today's first launch of Japan's HTV cargo vehicle is so important. The HTV will be one of the principal moving vans for carrying supplies up to the station, along with Europe's ATV, Russian Progress capsules, the shuttle (until its retirement), and eventually, commercial cargo vehicles. The shuttle has the most capacity—14 metric tons. The ATV carries 7.5 tons, the HTV 6 tons, and the Progress 2.5 tons.

The HTV is scheduled to dock automatically with the station next Friday, September 18. Follow its progress here.