Solid-fuel rockets contain cylinders of fuel that, depending on the manufacturing method, can take weeks to cure. Plus, it’s complicated to design the fuel so that the propulsive force varies in a predictable way as it burns. Keith Button spoke to researchers who think they have a better way to make solid fuel.

The term has been a handy label since the Apollo era, but a space race is not what’s playing out today between the United States and China. Space analyst John Logsdon offers a more nuanced view of the dynamic and what it might mean in the years ahead.

Maggie Wintermute, 30, systems engineer for Honeywell Aerospace