Researchers note that China's lunar lander is equipped with three backup engines, in contrast to the US design that depends on a single primary power source.
China and the United States are addressing this challenge in different ways. Their approaches could indicate the importance each country places on human life.
During the descent phase, a single main engine manages the entire journey from lunar orbit to the surface. For the ascent phase, one main engine serves as the only means of returning home.
If that single engine malfunctions, there is no alternative. This configuration, according to a peer-reviewed paper published in March in the journal *Chinese Space Science and Technology*, "has some obvious flaws."