A Chinese citizen will walk on the surface of the Earth's moon in a mission carried out by the government of mainland China. These footsteps will occur on or before the Chinese New Year of January 25, 2020, and will be reported as fact by at least three major non-Chinese news sources.
Note that even in 2003, some people still doubt that the U.S. ever made it to the moon. In the event of a dispute, the judge may assume that a widely reported Chinese moon landing actually occurred _unless_ a major and credible international news source reports that there is evidence to the contrary. It should be easy enough for major world governments to track the progress of the Chinese vessel to make sure that it does indeed make it to the moon; if the Chinese were to try to fake a landing, it should be obvious enough that there would be a large international outcry.
In case of a revolution in China between now and 2020, this claim will still be valid if a moon landing is made by the sovereign government in any part of China's borders in 2003, provided that such government is independent of other major world powers such as the U.S., E.U., and Russia.