https://www.defensenews.com/opinion/commentary/2021/07/08/maneuver-warfare-in-space-the-strategic-imperative-for-nuclear-thermal-propulsion/
Traditional chemical propellants used in current satellite designs are only designed to last for a limited life span, increasing the likelihood an adversary could “run them dry” by forcing more defensive maneuvers than their energy stores can sustain. Thanks to advances in technology, nuclear thermal propulsion would provide a solution to this challenge. Even though it sounds straight out of science fiction, advances in materials, testing and technology are now able to provide crucial space propulsion options for defense space applications.
Nuclear thermal propulsion provides much higher thrust and twice the propellant efficiency of legacy chemical systems. It works by transferring heat from the nuclear reactor to a liquid propellant. The heat converts the liquid into a gas, which expands through the engine nozzle to provide thrust for the spacecraft. An added benefit is the reactor can also electrically power mission payloads, greatly extending battery life and eliminating reliance on solar recharge.
This technology is not new: U.S. experts have been working on maturing these capabilities for the past 50 years. The field has now advanced to the point where nuclear propulsion will provide the rapid maneuver and presence needed for both defensive and offensive space applications — the very attributes that speak to today’s threat-driven mission requirements.