Positron Dynamics will develop a project for a rocket with a nuclear fragmentation engine. It is reported by Universe Today.
For any rocket engine, the key parameter is the specific impulse. The higher it is, the more acceleration a rocket with the same mass of fuel can develop. It is the too low specific impulse of chemical rocket engines (kerosene or hydrogen) that makes flights to Mars and Jupiter so difficult, and to Uranus and Neptune – almost impossible along the shortest trajectory (requiring a lot of fuel). Because of this, engineers are looking at alternative ways of propulsion, such as solar sails or nuclear rocket engines.
The nuclear fragmentation rocket engine, the concept of which the company will develop, uses the energy of fission of uranium nuclei to heat and create thrust. However, unlike a traditional nuclear engine, which heats hydrogen in a reactor and ejects its nozzles, plants of this type must eject nuclear fuel itself – fissile uranium. This allows you to heat it up to a temperature of several thousand degrees, and the higher the temperature, the greater the specific impulse.
However, traditional materials will not withstand such temperatures, so the engineers plan to use a number of innovations. For example, nuclear fuel particles are planned to be embedded in aerogels, ultralight materials with very low thermal conductivity. The airgel will allow fission products to be held together without the use of bulky structures. In addition, it will be necessary to create a magnetic nozzle using superconducting magnets. Since uranium (and the surrounding matter) will become hot and ionized, it will be possible to control the magnetic field by sending it flying in one direction, creating thrust.
This project is still at an early stage of theoretical study and can be implemented only after many years.