The US military wants to place a vast array of satellites between Earth and the moon using an experimental ‘nuclear thermal propulsion’ engine.
Using nuclear propulsion in space is not a new concept, with Freeman Dyson’s proposed ‘Super Orion’ nuclear rocket from the 1960s being just one example. Now, the US military is hoping to reignite the nuclear space race with a new form of propulsion currently under development.
According to The Daily Beast, the Pentagon is hoping to deploy a highly manoeuvrable fleet of satellites powered by ‘nuclear thermal propulsion’ in the cislunar region between Earth and the moon. Most importantly, it aims to beat Chinese technological efforts following China’s historic landing on the so-called ‘dark side of the moon’ in 2019.
In a budget proposal, the military’s research division, known as DARPA, said nuclear thermal propulsion will “expand the operating presence of the US in space to the cislunar volume and enhance domestic operations to a new high-ground, which is in danger of being defined by the adversary”.
DARPA has asked for $21m as part of its Demonstration Rocket for Agile Cislunar Operations (DRACO) programme for 2021. For 2020, it received $10m in backing, allowing it to test the engine before it can be passed on to the US Air Force.
DRACO has been described as a “high-assay low-enriched uranium nuclear-thermal propulsion system”. This means it will include a small nuclear reactor sitting atop a rocket. As the reactor heats up the chemical fuel– such as hydrogen – it pushes the propellant through a nozzle to change the rocket’s direction.
Shorter mission times
Elsewhere, America’s desire to occupy cislunar orbit continues through the actions of US president Donald Trump and NASA, with plans to potentially build a $30bn crewed space station, acting as a staging base for future moon missions.
A spokesperson for NASA said that compared with existing chemical propulsion, nuclear thermal propulsion “can enable shorter total mission times and enhanced flexibility for crewed Mars missions”.
Nuclear thermal propulsion is not the only proposed means of getting around the vastness of space. ESA, for example, has built and fired an electric thruster to ingest scarce air molecules from the top of the atmosphere.
By replacing onboard propellant with atmospheric molecules as fuel, a whole new class of satellites could be sustained in orbit for extremely long periods of time.
Meanwhile, NASA’s famous ‘EmDrive’ uses electromagnetism to propel itself forward in a vacuum at an unparalleled speed.