BY ONE well-known (if fictitious) criterion, the purpose of a space programme is to boldly go where no man has gone before. China, however, has a different plan: to boldly go back where men have already been. Specifically, with the release on December 29th of an official space-policy paper, it has said it wants to send people to the moon.

The last earthling to leave a footprint on the lunar surface, Eugene Cernan, did so in 1972. He was (and is) American. According to the new paper—the first of its kind since 2006—the next print in the regolith is likely to be Chinese. The country's experts have long discussed the possibility of such a mission, but this is the first official acknowledgment of a decision to proceed.

The document is, however, more than a mere claim to vainglory. It outlines a programme that will, if fully implemented, make China a space power equal to America and Russia.

One goal for the next five years is to improve China's Long March rockets, the workhorses that launch its satellites. The Long March-5, in particular, is intended to be able to lift 25 tonnes into low Earth orbit. (Perhaps significantly, this is 600kg more than America's space shuttles could manage.) Another part of the plan is to upgrade the country's satellite networks. A series of high-resolution Earth-observation satellites is to be launched over the next five years, and by 2020 the Beidou global-positioning and navigation system, a set of 35 satellites equivalent to America's Global Positioning System, should be in place. That will provide a boost to the command and control capabilities of China's armed forces. Progress was also promised on Tiangong-1, China's newly launched space station. And there will be unmanned flights to the moon, including sample-return missions, and manned orbital flights to test life-support systems.

The one place China does seem unlikely to be going, ironically, is the so-called International Space Station. This is an American-led venture and the United States seems reluctant to extend the term “International” to include China. That is partly because of paranoia about sharing technology with China, according to John Pike, the head of GlobalSecurity.org, an American think-tank. But it is also possible to detect a sense of pique that China is willing to do things (like going to the moon, and even just having a space programme that can put humans into orbit) which America, at the moment, can't.

Ultimately, manned space flight is futile. All the scientifically and practically important stuff can be done by robots. Nevertheless, symbols count. If the next man (or woman) on the moon is Chinese, many people will see it as a sign that America has been surpassed again.