General Atomics Electromagnetic Systems (GA-EMS) has successfully tested a new radioactive fuel that can survive the harsh environment of a nuclear rocket reactor. This is a positive development for powering spacecraft in the future.
To date, the common way of propelling spacecraft is through chemical rockets, which put the first satellite into space, the first man on the Moon, and sent the first deep space probes out of the solar system.
However, chemical rockets have also reached the limits of their capabilities. Since the first German V-2 rocket reached space in 1942, rockets have tended to be made larger, or made more efficient through innovations peripheral to the rocket engine itself.
On the other hand, ion drives and solar sails are also alternatives to chemical rockets, but these produce minuscule thrust and have limited applications.
Space engineers need something at least a third more powerful than the best chemical rocket’s performance to meet ambitious projects. Such an engine would allow for fast shuttles between low Earth orbit and the Moon, quickly shift orbits at short notice, and implement missions to send large crewed spacecraft to Mars and other planets in a reasonable time frame.
The most advanced candidate is currently the Nuclear Thermal Propulsion (NTP) system or nuclear rocket, which removes the burning chemical fuel method and replaces it with a nuclear reactor that is used to heat a propellant. The propellant is hydrogen or another material, including water, as the propellant doesn’t provide any power itself. It’s just reaction mass to be expelled to thrust according to Newton’s First Law.
However, the process requires a reactor to operate at very high temperatures – 2,326 °C (4,220 °F), and withstand strong vibrations.
The recent tests made at NASA’s Marshall Space Flight Center at Redstone Arsenal, Alabama demonstrated that the newest fuel could survive without erosion or degradation at operational temperatures up to 3,000 °K (4,940 °F, 2,726 °C).
Through trials, the fuel was subjected to full reactor heat and hydrogen gas for 20 minutes, which is also about what a nuclear engine would have to endure during a boost maneuver.
