The Chinese are up to something new in space.

In August, data released by the U.S. military showed that two Chinese satellites had appeared to perform a rather complex "rendezvous" in space, and may have even touched.

"On-orbit rendezvous is a complex operation," wrote Brian Weeden for the Space Review, an industry journal. "The rendezvous of two Chinese satellites demonstrates that China is broadening its space capabilities."

According to the data, the rendezvous occurred on or around Aug. 19. It's unclear whether the two satellites actually touched or just managed to come within a couple hundred metres of each other.

If they touched, Weeden says, it would be a first.

Analysts are still poring over the data, but observers have noted that close-range manoeuvre like this are key to development of more complex space programs like space-stations.

New Scientist magazine also pointed out that such technology is also used to help clear out space junk, an increasingly problematic collection of trash in orbit around the planet.

A Chinese policy expert told that magazine that the actual reason is likely to be a test-run for proximity sensors to be used when China launches its first module for the Chinese space station in 2011. That space station is scheduled to add two more modules before 2015.

"Although the purpose behind the rendezvous is unclear at this time, the technical details of the event suggest that it could have been done to develop orbital rendezvous or satellite inspection techniques, which other countries are also developing," Weeden wrote.