Space

Lunar detour could lighten the launch load for manned missions to Mars

Lunar detour could lighten the...
An MIT study says a detour to the Moon could make repeated trips to the Red Planet more sustainable
An MIT study says a detour to the Moon could make repeated trips to the Red Planet more sustainable
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An MIT study says a detour to the Moon could make repeated trips to the Red Planet more sustainable
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An MIT study says a detour to the Moon could make repeated trips to the Red Planet more sustainable

Early last year, researchers at MIT floated the idea of "gas stations" in space that have the potential to cut the costs of future missions to the Moon considerably. Now a new study out of MIT says that, although possibly a little out of the way, the Moon would make a worthwhile refueling pit stop for manned missions to Mars by reducing the mass of a launch from Earth by 68 percent.

Every gram of mass launched from Earth into space costs serious money, so any reduction in launch weight can mean major savings. If a mission were able to top up on fuel at the Moon for its long trip to the Red Planet, then that fuel would not need to be launched from Earth and the mission could launch with a fraction of the fuel it would actually need.

However, as you might know, the Moon isn’t home to any refueling depot just yet – there’s not even a Starbucks there yet – so the study makes a few assumptions about what technologies may be established on the Moon by the time a manned mission to Mars is ready to get of the ground.

Namely, the study assumes the lunar soil and water found on the Moon could be mined and converted into fuel by infrastructure yet to be built on the lunar surface and that this fuel could then be launched in tankers from the Moon to depots at Lagrange points, where a Mars-bound crew would rendezvous with them and use them to refuel before heading on their way.

"This is completely against the established common wisdom of how to go to Mars, which is a straight shot to Mars, carry everything with you," says Olivier de Weck, a professor of aeronautics and astronautics and of engineering systems at MIT. "The idea of taking a detour into the lunar system … it’s very unintuitive. But from an optimal network and big-picture view, this could be very affordable in the long term, because you don’t have to ship everything from Earth."

Such an approach would replace the "carry-along" method used by the Apollo missions to the Moon, where everything was carried with the crews at all times, and the "resupply approach," like that used by the International Space Station (ISS), where resources are replenished on a regular basis. Called “in-situ resource utilization,” crews would make use of materials produced in space, such as rocket fuel produced from water ice, which has been found on the Moon and Mars.

The study is based on the PhD thesis of Takuto Ishimatsu, now a postdoc at MIT, who believes the results demonstrate the importance of developing infrastructure in space to produce resources. While such infrastructure wouldn’t be necessary for a single trip to Mars, it would make repeated journeys much more sustainable.

"Our ultimate goal is to colonize Mars and to establish a permanent, self-sustainable human presence there," says Ishimatsu. "However, equally importantly, I believe that we need to 'pave a road' in space so that we can travel between planetary bodies in an affordable way."

Source: MIT

13 comments
Gavin Roe
and transporting the payload to the moon ? we can use the space ladder or elevator and there would be no loss of momentum in the brief stop to the moon nor would a second launch be required would you be considering a nuclear launch ?
Chris White
But you then need some fuel to escape the moon. That is the problem with the moon, while it is small, it does have gravity, and fuel will be spent to escape it. It's one of the key reasons we haven't been back. It doesn't really offer any advantage in relation to the effort to get to and from.
Your fuel up stations should be orbital stations where fuel for escape velocity is much much less significant. Also, something closer to earth decreases amount of fuel needed by that much more.
Also, departure windows will probably be much more frequent.
RelayerM31
I'm thinking, just have multiple launches, assemble the Mars ship in orbit and head out. The Moon? Seriously, these guys need some engineer friends to bring their heads back down to planet Earth, so to speak.
zevulon
so the bvious thing for some time now about going back to the moon first with human beings , for the first time in 40 years, makes more sense than the nonsense lies sold to the public about the remote possibility of going to mars, make even MORE sense. who would have thought?
humans on mars is a lie before we either learn how to colonize and roboticize the moon with some human presence on the moon, or a major revolution in physics allowing for massless space engines.
bobcat4424
This is far from new information. Back in the 1960's, NASA scientists wanted two things after Apollo: a space station at the Earth-Moon LaGrange Point and a Big Dumb Lifter that would balance safety, throw weight, and cost. The military wanted the ISS and the Space Shuttle, both disasters, to be used for reconnaissance, command and control, and as weapons platforms. In fact the Shuttle bay was designed around a KH-series reconnaissance satellite. The first is still needed and SpaceX is working on the second.
One aspect that everyone is missing about SpaceX is that their upper stages are refuelable and reprogrammable. By NOT recovering them (as will eventually happen with the boosters) they could remain in space to be refueled and reused either as "space tugs" and Lunar/Mars landers.
Other technology that is going to help in addition to hugely reducing launch costs, will be 3D-printing, which will reduce the amount of spares necessary to be carried, metal extrusion, which can vastly increase the practicality of major components (such as long beams, and inflatable modules, which are far more cost effective than "tin cans."
Stephen N Russell
Use Moon as Fwd & rescue base. See Iwo Jima used in WW2 as base for B29s back from bombing Japan for Rescue IF warranted, same for Moon for missions coming Back from Mars. & build base on Moon to support Mars & asteroid mining alone
JoshuaDwayneBarnes
I guess they haven't watched enough anime smh. This idea has been solved eons ago. Space stations at the Lagrange points. duh! Minimal fuel needed to launch from there.
Wolf0579
I've been saying it to anyone who would listen, we should not have given up on the Moon. It's the "highest Ground" with respect to earth, and having a strong US presence there will reduce the chances of Chinese or Russian attempts to dominate other nations through intimidation. (They could literally throw moon rocks at any spot on the Earth. It would be like a nuclear bomb going off on impact.)
Lunar orbit is also the most logical place to build and fuel long-distance spacecraft, being at the top of the "gravity well" created by the Earth.
vidbeldavs
What Ishimatsu's analysis misses is that ISRU will be much more than fuel and water for life support. See -http://strategic.mit.edu/JSR_Final_Manuscript_Ishimatsu.pdf Since his analysis makes a strong case for lunar ISRU where ISRU is limited to fuel and life support an even stronger case emerges when ISRU is used to produce structures as well as photovoltaic systems such as proposed by Peter Schubert - https://ildwg.files.wordpress.com/2015/03/energy-resources-beyond-earth-ssp-from-isru-schubert.pdf . Structural elements of interplanetary spacecraft and radiation shielding are likely to be early targets due to large mass and no requirement for aerodynamic design. Thermal barrier shields from lunar basalts are also likely to be early targets for entry into the Martian atmosphere. 3D printing in space will develop very rapidly. The fuel depots, interplanetary craft including Earth to Moon transporters are likely to be largely built from lunar materials. Clearly, industrial development of the Moon-cislunar space needs to be a very high priority. The International Lunar Decade provides a framework for international collaboration to achieve breakthrough to sustainable operations in space. See - https://ildwg.wordpress.com/
the.other.will
"Our ultimate goal is to colonize Mars and to establish a permanent, self-sustainable human presence there"? Just who did these MIT people include in their "we"? This sort of speculation is just static years before the very 1st manned Mars mission.