On Jan. 3, the China National Space Administration successfully landed a lunar exploration vehicle on the far side of the moon. It was a remarkable technical achievement, possible only because China had already managed to put a relay satellite into a halo orbit some 40,000 miles (64,000 kilometers) beyond the moon, from which it can bounce signals from Earth down to the exploration vehicle (and vice versa), getting around the problem that the moon blocks direct communications with its far side.
China was a latecomer to outer space, launching its first satellite only in 1970. It also operates on the cheap, spending less than one-fifth as much on its programs as the United States, according to the Organization for Economic Cooperation and Development. However, China is now the world's second-greatest space power, and strategists are increasingly talking about a second space race, paralleling the original race between the United States and...