The X-37 is not a highly maneuverable space vehicle, Bakos noted. NASA’s Space Shuttle glided back from space “almost like a rock basically gliding down very steeply and plopping on the runway.” According to media reports on China’s tests, the vehicle was able to maneuver when it returned from space into the atmosphere “and be more aggressive in terms of its cross range,” he said. “That would be new in terms of technology.”

If one is to believe the Chinese government’s explanation that this was just a reusable space vehicle technology demonstration, “in and of itself that would be a very significant demonstration, not trivial by any means,” Bakos said. If China’s vehicle after reentering “maneuvered in some way that a typical space vehicle does not, that would be alarming.” But he cautioned that whether or not this was a weapon or a nuclear-warhead delivery system being tested is impossible to know without seeing the test data.

“If you see a vehicle make a hard left turn at high speed, that’s pretty interesting because it’s hard to do that with a typical space vehicle,” Bakos said. “They’re not designed aerodynamically to have that capability.”