Nuclear fusion propulsion technology has the potential to revolutionize space travel in terms of both speeds and fuel usage. The same kinds of reactions that power the Sun could halve travel times to Mars, or make a journey to Saturn and its moons take just two years rather than eight.

It's incredibly exciting, but not everyone is convinced this is going to work: the tech needs ultra-high temperatures and pressures to function.

To help prove the viability of the technology, the largest ever fusion rocket engine is now being built by Pulsar Fusion in Bletchley, in the UK.

The chamber, some 8 meters (26 feet) long, is scheduled to start firing in 2027.

As you might expect, replicating the Sun inside a rocket isn't easy. At the center of nuclear fusion propulsion is an ultra-hot plasma locked inside an electromagnetic field, and scientists are continuing to figure out how to do this in a stable and safe way.