China’s mysterious SJ-17 satellite

The extensive maneuvers in space of China’s SJ-17 satellite, launched in December 2016 on the maiden flight of China’s Long March 5 rocket, have satellite trackers and defense officials intrigued and concerned.

Now China, as far as we know, hasn’t done anything nefarious with this satellite. But it has approached to within “a couple of hundred meters” to an apparently dead Chinese communications satellite recently parked in the so-called graveyard orbit. That is incredibly close by space standards. (Also, that comsat may or may not actually be a dead satellite.) And, as space geeks can tell from the above chart, it has executed “proximity operations” with at least four Chinese satellites.

What does all this mean? Are the Chinese testing space war maneuvers to allow them to get close an enemy satellite to move it or disable it? Since the maneuvers to service a satellite — giving it new fuel or trying tor repair it, for example — are virtually indistinguishable from an offensive maneuver, we don’t know. We do know that Strategic Command’s Gen. John Hyten has made it clear China and Russia are building weapons that include satellites, lasers and other ground-to-space weapons. Russia has deployed three Kosmos satellites that appear designed to approach other nations satellites and destroy them. China has launched Shiyan satellites, reportedly able to use a grappling arm to move satellites.

SJ-17 could be testing anti-satellite capabilities, where either it approaches close enough to a target so that when it explodes it takes the target with it, or it grabs that satellite to take it over. Or it could be testing robot orbital maneuvering for the purpose of future satellite servicing missions.

In either case, China is demonstrating that its future satellites will have very sophisticated maneuvering systems, capable of doing any number of things in orbit.