SpaceX going it alone to harvest water

[Vultur]

I don't see SpaceX getting into the Lunar water business at scale. I do see some entrepreneur developing a cost effective extraction method at some point that changes the trades.

Maybe. I am not 100% sure that its being cost effective is possible though.

The energy cost of launch from the Moon is certainly less than that of launch from the Earth. But this is only an advantage in terms of cost-effectiveness if the energy of launch is a significant part of the cost of propellant in orbit. Do we know sufficiently well how the lunar polar ice is physically arranged (glacier sheets, frozen mud, something else?) to be able to determine the energy cost of mining it? If it's not convenient, cost-effective might just not be possible.

Another factor is the lifetime cost of the equipment working in the (probably pretty challenging) lunar polar crater environment.

--

Now, if the concern is that thousands/tens of thousands of tanker launches just won't be allowed (for environmental reasons, etc) then it may make sense. But not for *cost effectiveness* reasons.

And even then, is the Moon the obvious best source? If this is an environment where a massive Mars infrastructure exists, and if you have zero boiloff technology, maybe the propellant gets made on Mars (if easier access to ice + mining/propellant making infrastructure already existing matters more than higher lauhch delta-V requirement). Or maybe Deimos (lower delta V requirement than Moon)..

[OTV Booster]

Does the moon even have enough water to seriously mine for rocket fuel? 

Lox I can see due to oxygen being in the soil, but water would be needed for a lunar colony for human use, not broken down into hydrolox rocket fuel.  Break down the soil for rocks and use what water the moon has for the colony as water will be a precious commodity on the moon.  Hydrogen or methane can be brought from earth for rocket fuel, and maybe lox made on the moon since oxygen is has more mass as a liquid than hydrogen or methane.

How much and in what concentration are the big questions.


Opinion: basic survival use: hydration, cooking and hygiene, will use but not consume water. Losses will come from air lock cycling residuals and leaks. Industrial processes and products will be a mixed bag and rocket propellant will be total loss.


AIUI hydrogen from solar wind is available in surface rocks, and of course O (and OH?) Don't know about carbon or concentrations. Getting water precursors from rocks would take more infrastructure and energy than raw water but it's not impossible.


Economics is a funny thing. It's sensitive to circumstances. Raw water in time of little infrastructure has more *immediate* value than holding it back for speculative future use. Very short sighted but very human.


With the implicit but unproven assumption that we are going to the moon to stay, it makes a type of sense to use the cheap water now to enable the infrastructure that can harvest the expensive water tomorrow.

Once there is supply infrastructure in place using Lunar water/fuel means there is ready market for Asteriod water. Its lot easier to great a business case for Asteriod mining when there is existing market for mined resources. ie mt of H2O delivered to EML1 is worth $$mt.

That's a pattern. There's no market for a product but a visionary inventor/entrepreneur keeps plugging away until it's perfected and builds a market out of an idea.


Fifteen years ago the idea of reusable rockets was an industry joke. Five years ago the idea of a shortage of orbital lift didn't exist. Today we have both with one company adept at reuse, a second coming on line, several in the wings and a bunch of dinosaurs watching an incoming comet not even sure that it's a problem.


Asteroids will absolutely be Earths mining district in 50 years or less. Until then the moon is handy. That brings us back to the point of this discussion.


Will SpaceX/Musk go it alone if necessary to support their Mars ambitions?

[meekGee]

That's a pattern. There's no market for a product but a visionary inventor/entrepreneur keeps plugging away until it's perfected and builds a market out of an idea.


Fifteen years ago the idea of reusable rockets was an industry joke. Five years ago the idea of a shortage of orbital lift didn't exist. Today we have both with one company adept at reuse, a second coming on line, several in the wings and a bunch of dinosaurs watching an incoming comet not even sure that it's a problem.


Asteroids will absolutely be Earths mining district in 50 years or less. Until then the moon is handy. That brings us back to the point of this discussion.


Will SpaceX/Musk go it alone if necessary to support their Mars ambitions?

You could say that IF lunar mining could support a Mars campaign, they would have.

But it can't, so they won't.

That Ceres will become a key asset one day, I don't doubt for a minute, but that (as you say) is some 50 years later.

Will SpaceX go to the moon if not part of Artemis? Not sure. "It's complicated".

Will SpaceX send a water harvester/converter to Ceres within a decade?  That's interesting to me a lot more - since that's a key to so many things.

[redneck]

I don't see SpaceX getting into the Lunar water business at scale. I do see some entrepreneur developing a cost effective extraction method at some point that changes the trades.

Maybe. I am not 100% sure that its being cost effective is possible though.

..

I used the term "At some point" for reasons you point out. I don't see it being cost effective for someone right now to focus exclusively on Lunar water extraction. My "At some point" could be a decade or a century away and very dependent on economics at that time. It could be never.

It will be strongly dependent on proved reserves and available extraction techniques on the moon when we get that far. And on the alternatives available at that time. If a comet as suggested elsewhere in the thread is brought to Lunar orbit, it may be never. Or restrictions on Earth launch could drive the price of Lunar LOX through the roof. Everything is speculative at this point.

[Vultur]

I don't see SpaceX getting into the Lunar water business at scale. I do see some entrepreneur developing a cost effective extraction method at some point that changes the trades.

Maybe. I am not 100% sure that its being cost effective is possible though.

..

I used the term "At some point" for reasons you point out. I don't see it being cost effective for someone right now to focus exclusively on Lunar water extraction. My "At some point" could be a decade or a century away and very dependent on economics at that time. It could be never.

It will be strongly dependent on proved reserves and available extraction techniques on the moon when we get that far. And on the alternatives available at that time. If a comet as suggested elsewhere in the thread is brought to Lunar orbit, it may be never. Or restrictions on Earth launch could drive the price of Lunar LOX through the roof. Everything is speculative at this point.

.

Yeah. I was just saying that its being profitable depends on more than technology development, it probably also depends on the exact state of the water resources on the Moon which we don't know in detail.

Even given an environment where total Earth launch is constrained, the state of/difficulty of accessing Lunar water (vs asteroid water or whatever) would probably determine whether the Moon makes sense as a source vs Mars or Deimos or asteroids. (Comets are probably too delta v intensive.)

[Twark_Main]

Does the moon even have enough water to seriously mine for rocket fuel? 

Lox I can see due to oxygen being in the soil, but water would be needed for a lunar colony for human use, not broken down into hydrolox rocket fuel.  Break down the soil for rocks and use what water the moon has for the colony as water will be a precious commodity on the moon.  Hydrogen or methane can be brought from earth for rocket fuel, and maybe lox made on the moon since oxygen is has more mass as a liquid than hydrogen or methane.

How much and in what concentration are the big questions.


Opinion: basic survival use: hydration, cooking and hygiene, will use but not consume water. Losses will come from air lock cycling residuals and leaks. Industrial processes and products will be a mixed bag and rocket propellant will be total loss.


AIUI hydrogen from solar wind is available in surface rocks, and of course O (and OH?) Don't know about carbon or concentrations. Getting water precursors from rocks would take more infrastructure and energy than raw water but it's not impossible.


Economics is a funny thing. It's sensitive to circumstances. Raw water in time of little infrastructure has more *immediate* value than holding it back for speculative future use. Very short sighted but very human.


With the implicit but unproven assumption that we are going to the moon to stay, it makes a type of sense to use the cheap water now to enable the infrastructure that can harvest the expensive water tomorrow.

See Andy Weir's second book, Artemis. No relation!   

[Slarty1080]

Are SpaceX going it alone to harvest water? Not if they can help it, but I fear they may not be able to help it. No doubt Congress / NASA are going to faff about a lot and will be extremely safety conscious over something like ISRU on Mars. Landing opportunities will be used to test the process in various ways and as the opportunities tick past at some point Elon Musk will realize that his 60th birthday is approaching (or has arrived) and will lose patience.

He won't be entirely reckless, but he will be a lot more adventurous and open to some risk than NASA ever would. At that point he should be able to afford to try it out. Maybe Congress could be persuaded to pay for a lot of the tech development under the guise of a human mission in 2045 or whenever. That way if or when anything goes wrong they can blame Musk for going to early or if it all works out, bask in the reflected glory.

There might even be (depending on the Administration in power) a tacit approval. Just as long as Musk gets enough money to make it easy plus cover for nuclear (if used) and Planetary protection (if there are any questions).

[DanClemmensen]

Maybe Congress could be persuaded to pay for a lot of the tech development under the guise of a human mission in 2045 or whenever.

So far, Congress has been very reluctant to fund SpaceX. Congress funded CRS, CCP, and Artemis. In each case, NASA made competitive contract award. In each case SpaceX made a low bid and won it. for CCP some congressfolks were unhappy it was not sole-source to Boeing. For Artemis, Congress went ballistic when only SpaceX won, so they gave extra money to NASA for what was effectively a directed second-source contract to Blue Origin.

I think the best we can hope for is for congress to allow NASA to contract for transportation services to Mars. In a rational world, Congress would also direct NASA to contract for end-to-end transportation services to the Moon, but the SLS/Orion pork machine is too entrenched.

[freddo411]

This is an outgrowth of https://forum.nasaspaceflight.com/index.php?topic=50806.msg2738114#msg2738114
where harvesting water for propellant struck me as reason enough for SpaceX to continue their lunar endeavors even if they were cut from the Artemis program. ISTM the issue was far enough removed from the discussions intent that it warranted its own discussion.

The topic says it all. Is a lunar mission in SpaceX's long term interest? Does it further their Mars aspirations?

Make it make economic sense.

..snip

The deltaV from lunar polar surface to LEO is 5.7km/sec. 

..snip

The only way LOX production makes sense on the Moon is to directly support a Moon colony, in an identical manner to the proposals for Mars - and mostly for "going home".

Measuring by comparing costs is the right metric.   However, your math is missing an efficient architecture.

A good architecture would be:

Mars bound Starships arrive in LEO, then refuel enough to travel to NRHO or other very high orbit.   
NRHO would host an oxygen propellent depot.   
Starships would refuel there for the Mars transfer orbit.
Starships would use an efficient oberth maneuver to start toward Mars

[InterestedEngineer]

Mars bound Starships arrive in LEO, then refuel enough to travel to NRHO or other very high orbit.   
NRHO would host an oxygen propellent depot.   
Starships would refuel there for the Mars transfer orbit.
Starships would use an efficient oberth maneuver to start toward Mars

That won't work.  You'll spend more fuel de-orbiting from a circular to an elliptical orbit than you would get benefit from the Oberth maneuver.

"always be in elliptical orbit" - including the propellant.

[wes_wilson]

Lunar point to point would be another use case to consider.  Any long term human establishment is going to want to have mobility around the surface.  Absent roads, tunnels, and other infrastructure, Starship P2P may be an efficient mode of moving material around the moon.

[spacenut]

SpaceX's ultimate goal is Mars.  Except for the Artemis lander for the moon, I don't think SpaceX is at all interested in the moon.  Once a colony is established on Mars, SpaceX in the distant future might mine asteroids and will need water harvesting at Ceres.  That is at least 50-100 years out.  Mars is the goal.  Moon is secondary. 

[DigitalMan]

It would be interesting if you could make a hopper that uses kinetic energy to move around, like a frog.

You could potentially take samples with every hop and quickly create a large collection

[DanClemmensen]

SpaceX's ultimate goal is Mars.  Except for the Artemis lander for the moon, I don't think SpaceX is at all interested in the moon.  Once a colony is established on Mars, SpaceX in the distant future might mine asteroids and will need water harvesting at Ceres.  That is at least 50-100 years out.  Mars is the goal.  Moon is secondary.

SpaceX built Crew Dragon in response to NASA's CCP program, but they also offer service to anyone who will pay for it. they have flown twelve crewed CCP missions and seven crewed non-NASA missions.

I suspect that SpaceX will offer private missions to the Moon, assuming they have customers. This will require SpaceX to develop a mission plan that uses only SpaceX vehicles, not SLS/Orion. A mission that uses Crew Dragon to get crew to LEO Is likely too expensive for any customers except governments. I would love to see a mission by four crew, one each from (say) south Korea, Singapore, Indonesia, and Taiwan. Basically a "flags and footprints" mission, just not the flags you were thinking of.

A cost-effective private Moon mission may need to wait until a crewed EDL Starship is certified as part of the Mars development effort. This mission would land as many as 20 crew on the Moon, using the EDL Ship plus an HLS Ship, Depot, and tankers.

[scientist]

Mars bound Starships arrive in LEO, then refuel enough to travel to NRHO or other very high orbit.   
NRHO would host an oxygen propellent depot.   
Starships would refuel there for the Mars transfer orbit.
Starships would use an efficient oberth maneuver to start toward Mars

That won't work.  You'll spend more fuel de-orbiting from a circular to an elliptical orbit than you would get benefit from the Oberth maneuver.

"always be in elliptical orbit" - including the propellant.

This is no longer true once you get far enough that your orbit is at the edge of the body's gravitational influence. See for example Escapade's orbit:

[InterestedEngineer]

Mars bound Starships arrive in LEO, then refuel enough to travel to NRHO or other very high orbit.   
NRHO would host an oxygen propellent depot.   
Starships would refuel there for the Mars transfer orbit.
Starships would use an efficient oberth maneuver to start toward Mars

That won't work.  You'll spend more fuel de-orbiting from a circular to an elliptical orbit than you would get benefit from the Oberth maneuver.

"always be in elliptical orbit" - including the propellant.

This is no longer true once you get far enough that your orbit is at the edge of the body's gravitational influence. See for example Escapade's orbit:

Interesting.  So you'd presumably toss LOX into this orbit and figure out how to rendezvous with it.

Alas there's not a lot of detail on this orbit on the intarwebs.  Perhaps you could find some?  For example wikipedia says:

hen ESCAPADE will change course to dive within 600 km of Earth for a gravity assist and execute its escape burns to place it on a trajectory to Mars

What's the deltaV for that course change?

What's the orbital period around L2?

How hared to rendezvous with LOX given that orbital period?

What happens if the moon's gravitational influence changes this orbit?

[InterestedEngineer]

answering some of the "moon fuel to L1" questions I raised.

It's about 2.7km/sec from lunar surface to EM-L1 halo orbit.   Since the exhaust velocity of a starship is 3.6km/sec that makes it about half the fuel you have to burn from lunar surface to get it to the fuel keeping station at EM-L1.

Now, it's a trivial < 100m/sec burn to de-orbit to an elliptical earth grazing orbit for an Oberth burn, so that's basically rounding error.  That's the huge advantage of a Lagrange point for parking fuel depots.

So the EM-L1 point is a great place to put fuel depots, whether the fuel is from the moon or the earth.  You can get starships to solar escape speeds quite easily.  Mars transits are less than 100 days and this includes a braking burn at Mars to slow down enough for aerobraking to still work.

Now, it's about 3.2km/sec to get fuel from LEO to EML1.   That's about 65% of the fuel used.

If it costs us in the long run $10/kg to get fuel to LEO, it thus will cost us $28/kg to get it to EML1.

So whatever the Moon's LOX production costs are, they'd better be less than 28/2 = $14/kg or it'll never be economically viable.  Probably less than $10/kg to pay for the development cost.

On Earth LOX is about $0.1/kg so the production costs on earth are rounding error.

Think we can get production costs for LOX on the moon to less than $10/kg?

[OTV Booster]

SpaceX's ultimate goal is Mars.  Except for the Artemis lander for the moon, I don't think SpaceX is at all interested in the moon.  Once a colony is established on Mars, SpaceX in the distant future might mine asteroids and will need water harvesting at Ceres.  That is at least 50-100 years out.  Mars is the goal.  Moon is secondary.

Mars is the goal but if the water works out it might be a means to that end.

[OTV Booster]

answering some of the "moon fuel to L1" questions I raised.

It's about 2.7km/sec from lunar surface to EM-L1 halo orbit.   Since the exhaust velocity of a starship is 3.6km/sec that makes it about half the fuel you have to burn from lunar surface to get it to the fuel keeping station at EM-L1.

Now, it's a trivial < 100m/sec burn to de-orbit to an elliptical earth grazing orbit for an Oberth burn, so that's basically rounding error.  That's the huge advantage of a Lagrange point for parking fuel depots.

So the EM-L1 point is a great place to put fuel depots, whether the fuel is from the moon or the earth.  You can get starships to solar escape speeds quite easily.  Mars transits are less than 100 days and this includes a braking burn at Mars to slow down enough for aerobraking to still work.

Now, it's about 3.2km/sec to get fuel from LEO to EML1.   That's about 65% of the fuel used.

If it costs us in the long run $10/kg to get fuel to LEO, it thus will cost us $28/kg to get it to EML1.

So whatever the Moon's LOX production costs are, they'd better be less than 28/2 = $14/kg or it'll never be economically viable.  Probably less than $10/kg to pay for the development cost.

On Earth LOX is about $0.1/kg so the production costs on earth are rounding error.

Think we can get production costs for LOX on the moon to less than $10/kg?

If tanker can deliver 250t of propellant to LEO at $10/kg that's a launch cost of $2.5m. Is that reasonable? In what time frame?


Transfer from LEO to L1 would be a depot, a tanker or something in between to save dry mass. From lunar surface ultimately a sling. Yeah, it's a new system to develop but the utility of lunar propellant kicks in later as the number of mars ships grows, giving both time and incentive for development.


A question on the 100m/sec burn from EM-L1 to mars. Can it be run in reverse to bring a returning mars ship to L1 with ~100m/sec burn? That would be another trade space to look at. With carbon or CO2, lunar water can make methane. Earth needs to get rid of CO2 but it's also dirt cheap on Mars.

[rsdavis9]

The question of local surface transport.

1. Hop from one location to next ala p2p
2. Continuous thrust to stay aloft and then horizontal movement ala 2001 movie 
3. Surface with wheels and batteries and charging stations.

I think 1 and 3 will be the future for both the moon and mars. They both have flat plains across the majority of the surface. They don't have vegetation or liquid erosion to hamper travel. It will have speed limits but the majority will be fairly easy. Charging stations will be solar panel farm and buried insulated batteries. On mars 12-24 hours of battery storage on the moom 14-28 days of storage.

2 might still be used for surveys where slow and close to surface are needed for some sort of scanning. Or very short distances where fuel use is more important.