In the 21st century race to the moon, there is a question that engineers must ask: what happens when the main engine fails? China and the United States are answering this in contrasting ways. Their answers could reveal the value they place on human life. From the Apollo Lunar Module in the 1960s to Nasa’s new Orion spacecraft for the Artemis programme, the American architecture relies on a single, powerful main engine to do the heavy lifting. On the descent stage, one main engine controls the...

As the United States quietly pulls its most precious military assets away from the coasts of Asia, they are falling back to places like Guam in Micronesia, a US island territory far beyond the reach of most conventional missiles. It sounds like a retreat but for the Chinese military it is actually a much trickier problem. In modern warfare, distance can become a shield and dispersion a weapon. This is the puzzle a team of Chinese defence scientists has been solving. Their answer, published...