Supersonic Laser-Propelled Spacecraft Could Allow Astronauts to Explore the Universe

Can you imagine flying through space with a laser-powered rocket? It seems like something more about of science fiction than reality, right? Yet a new method for improving the thrust generated by laser-propulsion systems could bring laser-powered rockets closer to reality.

Currently, the maximum speed of a spacecraft is limited by the amount of solid or liquid fuel that it can carry. Achieving higher speeds means that more fuel needs to be burned-fuel that needs to be carried into space. In theory, though, these loads could be reduced with the help of laser propulsion.

One of the most promising proposed systems for laser propulsion involves a process called laser ablation. This occurs when a pulsed laser beam strikes a surface, heats it up, and burns off material to create what is known as a plasma plume. The outflowing from the plasma plume generates additional thrust to power the spacecraft.

This new method, though, integrates a laser-ablation propulsion system with the gas blasting nozzles of a spacecraft. Combining the two systems can increase the speed of the gas flow out of the system to supersonic speeds while reducing the amount of fuel burned.

That said, this new system is limited. The supersonic gases can be unstable as they flow through the gas nozzle, and shock waves and "choke" the inlet of the nozzle, reducing thrust. These effects and be reduced, though, with the help of a laser-ablation plasma plume that is redirected so that it will flow close to the interior wall of the nozzle.

"Summarizing the data obtained, we can forecast the applications of the supersonic laser propulsion techniques not only for launching small satellites to Earth orbits but also for additional acceleration of supersonic aircrafts to achieve Mach 10 and more," said Yuri Rezunkov, one of the researchers, in a news release.

The findings could be a huge step forward for space travel. By increasing the speed of spacecraft, we can travel further afield in less time, opening up the universe for further exploration.

The findings are published in the journal Applied Optics.