Pulsar Fusion wants to use nuclear fusion to make interstellar space travel a reality

Image credits: Pulsating Fusion

Space propulsion company Pulsar Fusion has begun construction of a large nuclear fusion chamber in England as it races to become the first company to launch a nuclear fusion propulsion system into space.

Nuclear fusion propulsion technology, arguably a golden goose of the space industry, could cut travel time to Mars in half and cut travel time to Saturn’s moon Titan to two years instead of 10 Sounds like science fiction, but Pulsar CEO Richard Dinan told TechCrunch in a recent interview that fusion propulsion was inevitable.

You have to ask yourself, can humanity do fusion? he said. If we can’t, then all of this is irrelevant. If we can and can, then fusion propulsion is totally inevitable. It is irresistible to human space evolution. This is happening, because the application is irresistible.

For much of its 11-year history, the Oxfordshire, UK-based company has focused primarily on fusion research. More recently, Pulsar has begun developing products that could bring in revenue as research continues: an electric Hall-effect thruster for spacecraft and a second-stage hybrid rocket motor. The company also received funding from the British Space Agency in 2022 to develop a nuclear fission-based propulsion system, together with the Nuclear Advanced Manufacturing Research Center and the University of Cambridge.

But for Pulsar, the future of deep space travel lies firmly in fusion propulsion. Fusion for space propulsion is probably much simpler than fusion for electricity generation here on Earth, in part because very cold conditions in space and a near-perfect vacuum favor fusion reactions. The incredible energy density of those reactions would produce super-fast travel speeds and require only a fraction of the fuel of existing propulsion systems.

While such systems are very expensive, speed in space is fungible with money, Dinan said.

If I can save you X many days in space, I can charge you for it, he said.

One good thing about this technology, even if it hasn’t yet been demonstrated in a system, is that the underlying physics is well understood: fusion works similar to our sun, confining an ultra-hot plasma within an electromagnetic field. The challenge for the scientists was stabilizing that plasma for any significant amount of time. That’s Pulsar’s next task: to build an eight-meter fusion chamber to bring plasma to ultra-hot temperatures and create exhaust velocities fast enough for interstellar travel.

The difficulty lies in learning how to hold and confine the superheated plasma within an electromagnetic field, Pulsar CFO James Lambert explained in a statement. Plasma behaves like a weather system in terms of being incredibly difficult to predict using conventional techniques.

The company has already started construction on that reaction chamber in Bletchley, England. It has partnered with New Jersey-based Princeton Satellite Systems to use supercomputer simulations to better understand how plasma will behave under electromagnetic confinement. The pair will also shape how plasma would behave exiting a rocket engine, and that data will help inform the design of the Pulsar rocket engine. The next step would be an in-orbit demonstration, in which the company would attempt to launch a nuclear fusion propulsion system into space for the first time.

If we were to leave our solar system within a human lifetime, there is no other technology we know of that can do it, Dinan said.