A new MIT study suggests that a manned mission to Mars may lighten its launch load considerably by refuelling on the Moon.
Previous studies have suggested that lunar soil and water ice in certain craters of the Moon may be mined and converted to fuel.
Assuming that such technologies are established at the time of a mission to Mars, the Massachusetts Institute of Technology (MIT) group has found that taking a detour to the Moon to refuel would reduce the mass of a mission upon launch by 68 per cent.
The group developed a model to determine the best route to Mars, assuming the availability of resources and fuel-generating infrastructure on the Moon.
Based on their calculations, they determined the optimal route to Mars, in order to minimise the mass that would have to be launched from Earth.
They found the most mass-efficient path involves launching a crew from Earth with just enough fuel to get into orbit around the Earth. A fuel-producing plant on the surface of the Moon would then launch tankers of fuel into space, where they would enter gravitational orbit.
The tankers would eventually be picked up by the Mars-bound crew, which would then head to a nearby fuelling station to gas up before ultimately heading to Mars.
The MIT team proposes that missions to Mars and other distant destinations may benefit from a supply strategy that hinges on “in-situ resource utilisation” – the idea that resources such as fuel, and provisions such as water and oxygen, may be produced and collected along the route of space exploration.
Materials produced in space would replace those that would otherwise be transported from Earth.
To see whether fuel resources and infrastructure in space would benefit manned missions to Mars, Takuto Ishimatsu, who conducted the work as part of his PhD thesis and is now a postdoc at MIT, developed a network flow model to explore various routes to Mars – ranging from a direct carry-along flight to a series of refuelling pit stops along the way.
Ishimatsu said the research demonstrates the importance of establishing a resource-producing infrastructure in space.
He emphasises that such infrastructure may not be necessary for a first trip to Mars. But a resource network in space would enable humans to make the journey repeatedly in a sustainable way.
“The optimisation suggests that the Moon could play a major role in getting us to Mars repeatedly and sustainably,” said Olivier de Weck, a professor of aeronautics and astronautics and of engineering systems at MIT.
“People have hinted at that before, but we think this is the first definitive paper that shows mathematically why that’s the right answer,” he said.