If we want to explore the farthest reaches of our Solar System, current rocket speeds are just not up to scratch.
Even with our fastest engines, it’s a three-year round trip to Mars – and that’s our closest neighbour.
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Stepping up to the plate to tackle this problem are scientists at Ohio State University.
With NASA funding, they are developing a rocket which they say can cut the time it takes to get to the Red Planet by half.
The key element to achieving this? Liquid uranium.
A new way to get into space?
Called the centrifugal nuclear thermal rocket (CNTR) system, instead of relying on chemical combustion or solid nuclear fuel rods to heat rocket propellant (like those used in engines tested at the beginning of the Space Race), the engine spins the uranium at very high speeds to keep it in liquid form.
Propellant is then bubbled through this molten uranium, reaching a very high temperature before it is fired out of the engine nozzle.
This, they say, can produce three to four times the thrust of a chemical rocket.
"You could have a safe one-way trip to Mars in six months, for example, as opposed to doing the same mission in a year," says engineering PhD Spencer Christian, who is leading the construction of the prototype.
The CNTR rocket can also use a range of propellants, including those that are commonly found in space, such as ammonia, methane, hydrazine and propane.
As these can be found in asteroids and other space objects, this could open up the possibility of refuelling en route, extending the rocket’s range.
The system is still in the early stages of development, explains Dean Wang from the project team: "We have a very good understanding of the physics of our design, but there are still technical challenges we need to overcome.
"We need to keep space nuclear propulsion as a consistent priority in the future, so that the technology can have time to mature."
