Best path to lunar provenance propellant?

[Frank]

Getting stuff to space is very expensive, about $2 million per ton to LEO (currently).  ~$150 million for 63.8t, so ~$2.3 million per tonne on falcon heavy expendable.  Capabilities & Services | SpaceX:  http://www.spacex.com/about/capabilities

Assuming we don't want to wait for BFR or SLS, what CAN be done with Falcon Heavy, lowest budget, fastest kickstart of propellant mining and delivery to LEO?

Do we NEED to have people ON the moon or can robots do the job?  I haven't seen robots that can do this yet, so is it faster/better to start on a moon base or work on robots, or do both?

Are there pieces of infrastructure that can be laid down right away, machines that can be operated tele-robotically?

 

How would you do it?

 

[Area54]

I am somewhat confused by your post. Perhaps you can help me remove that confusion, one point at a time. Let's start with paragraph 1.

• The link specifies $90m to LEO with Falcon Heavy with a load of 63.8t. That's ~$1.4m/t, not $2.3
• The only way I can see that you got ~$150 million for 63.8t was to add the charge for the Falcon 9 to that for the Falcon Heavy. If you did that, why? If not, how did you come by your $150 million figure?
• Why did you desrcibe the Falcon Heavy as the Falcon Heavy expendable? The whole point of the Space-X rockets is that they are reusable.

I look forward to your clarificatrion.

[Endy0816]

Probably look at obtaining Oxygen from the dust and rocks. Multiple ways to use the Oxygen(energy storage, breathing) and useful byproducts.

[Frank]

7 hours ago, Area54 said:

I am somewhat confused by your post. Perhaps you can help me remove that confusion, one point at a time. Let's start with paragraph 1.

• The link specifies $90m to LEO with Falcon Heavy with a load of 63.8t. That's ~$1.4m/t, not $2.3
• The only way I can see that you got ~$150 million for 63.8t was to add the charge for the Falcon 9 to that for the Falcon Heavy. If you did that, why? If not, how did you come by your $150 million figure?
• Why did you desrcibe the Falcon Heavy as the Falcon Heavy expendable? The whole point of the Space-X rockets is that they are reusable.

I look forward to your clarificatrion.

It's $90m for a reusable falcon heavy (landed boosters) which has a reduced payload capacity because fuel must be reserved for landing and also legs and grid fins must be lifted, taking away payload capacity.  We can only guess at the price, but $2.3m/t is a conservative and known number.  I was using $2m/t, but even $1m/t isn't out of the realm of possibility, given reuse ability, better performance and enhancements.

 

 

[Area54]

2 minutes ago, Frank said:

It's $90m for a reusable falcon heavy (landed boosters) which has a reduced payload capacity because fuel must be reserved for landing and also legs and grid fins must be lifted, taking away payload capacity.  We can only guess at the price, but $2.3m/t is a conservative and known number.  I was using $2m/t, but even $1m/t isn't out of the realm of possibility, given reuse ability, better performance and enhancements.

Thank you for the clarification although it creates further puzzlement. As far as I am aware the data in the link you provided is for a resuable Falcon Heavy and the price ($90m) takes account of the reduced payload capacity. Consequently my figure of $1.4 million/t is valid. I would aslo dispute your statement that "we can only guess at the price". Space-X have provided a specific price on that link. No guessing is required.

On 14/03/2018 at 6:33 PM, Frank said:

Assuming we don't want to wait for BFR or SLS, what CAN be done with Falcon Heavy, lowest budget, fastest kickstart of propellant mining and delivery to LEO?

Next point of confusion. (My apologies for not following your argument properly.) Your propellant mining appears to be in relation to the moon, so what is the relevance of placing payload in LEO? Again, I look forward to your clarification.

[Frank]

3 hours ago, Endy0816 said:

Probably look at obtaining Oxygen from the dust and rocks. Multiple ways to use the Oxygen(energy storage, breathing) and useful byproducts.

Extracting Oxygen from lunar dust (regolith) is possible.  I was assuming that we will have confirmed accessible water in the deep craters of the (south) pole, making water, air and some other gases available on the moon.

Here is a pretty good paper on extracting lunar water for propellant.  It's a 16 year plan.  http://www.spudislunarresources.com/Papers/Affordable_Lunar_Base.pdf  Interesting to note, this 2010 paper pegs launch cost at $5m/t.

 

 

2 minutes ago, Area54 said:

Thank you for the clarification although it creates further puzzlement. As far as I am aware the data in the link you provided is for a resuable Falcon Heavy and the price ($90m) takes account of the reduced payload capacity. Consequently my figure of $1.4 million/t is valid. I would aslo dispute your statement that "we can only guess at the price". Space-X have provided a specific price on that link. No guessing is required.

Next point of confusion. (My apologies for not following your argument properly.) Your propellant mining appears to be in relation to the moon, so what is the relevance of placing payload in LEO? Again, I look forward to your clarification.

OK, it's not my understanding, but I'm happy to use $1.4m/t as a baseline.  With competition, prices may drop further.

Putting propellant directly into LEO costs a certain amount.  Presumably, it is cheaper to send propellant from the moon, because delta-v is much lower.  So the question was, how soon and how would this be accomplished?

Another way to look at it is, instead of building another space station (Deep Space Gateway) in low lunar orbit, it might be better to build a moon base so that water, oxygen, etc.  don't need to be sent from earth to it and at a later time, propellant can ALSO be returned to LEO reducing the cost of sending people and cargo to the Moon and Mars.  So, what's the fastest way to get this chicken-egg thing going?

 

[Endy0816]

2 hours ago, Frank said:

Extracting Oxygen from lunar dust (regolith) is possible.  I was assuming that we will have confirmed accessible water in the deep craters of the (south) pole, making water, air and some other gases available on the moon.

Here is a pretty good paper on extracting lunar water for propellant.  It's a 16 year plan.  http://www.spudislunarresources.com/Papers/Affordable_Lunar_Base.pdf  Interesting to note, this 2010 paper pegs launch cost at $5m/t.

Yeah, I'm thinking from the minerals themselves. Oxygen is crazy common and we don't have to worry about losses.

Hydrogen is a pain in the arse gas.

Edited March 16, 2018 by Endy0816

[Frank]

6 minutes ago, Endy0816 said:

I'm thinking from the minerals themselves. Oxygen is crazy common and we don't have to worry about losses.

Losses?  I'm a bit confused, can you elaborate a bit?  A process for extracting oxygen while sintering regolith into bricks exists, as does a process while smelting regolith for its resources IIRC.  Oxygen is also the heaviest part of 6:1 in a hydrolox propellant, so even extracting oxygen might kickstart the process.

Methalox is interesting because the amount of hydrogen needed is reduced, replaced by Carbon, CH4, and COx is also found in the lunar ice.

 

[Frank]

3 hours ago, Endy0816 said:

Hydrogen is a pain in the arse gas.

Oh, hydrogen boil-off and insulation requirements - gotcha.  Methane helps there too.

 

[Endy0816]

Possible for this stuff to escape into space. Low gravity, solar wind.

I'm concerned a human colony could deplete the entire supply. Colony will never be perfectly sealed and using it as a fuel will deplete it even more rapidly.

I'm thinking Oxygen would be better all around.

[Frank]

24 minutes ago, Endy0816 said:

Possible for this stuff to escape into space. Low gravity, solar wind.

I'm concerned a human colony could deplete the entire supply. Colony will never be perfectly sealed and using it as a fuel will deplete it even more rapidly.

I'm thinking Oxygen would be better all around.

If I understand the process, gases are blown by solar winds from the earth to the moon, so it's trapped earth gases and not a finite resource.  Also, if we don't use it, who will?  Is there any benefit to anyone not using lunar ice?   I have to admit, this wasn't something I gave much thought...

 

[Frank]

A good point has been made that oxygen is certainly available on the moon, so that a kickstart process might go for the perhaps more straightforward but more energy intensive path to resources than trying to figure out how to extract water from a resource of unknown state, ice or hydroxyl, concentration etc...

So land solar panels, a chariot rover bulldozer, maybe a robot arm + android (cherry picker and human analog) and extra batteries, plus an oxygen extraction "machine".  If this machine can either make bricks or sinter the regolith surface in place, while extracting oxygen, we can tele-robotically prepare the landing pad, habitat foundation, and roads while extracting oxygen. 

Hydrogen would have to be sent from earth.  delta-v to EML1 or EML2 is 2.52 km/s, so it would take less than 1/5th the mass in hydrogen to bring lunar oxygen to EML points.  Assuming 450s Isp and 5% ship mass (rough estimate).

At the very least, oxygen won't need to be sent from earth.  Hydrogen instead of water (8:1) mass savings or 11% the mass.  Fuel for a return trip is 6:1, so 15% the mass compared to bringing hydrogen AND oxygen.

Once humans land on the moon, tele-robotics lose the 3 second delay and 3d printing can be used to adapt machines to extract resources.

 

 

Transportation Architecture for Cislunar Space ssp2015-sowers.pdf: https://www.mtu.edu/ece/department/faculty/full-time/zekavat/pdfs/ssp2015-sowers.pdf

[Frank]

Adding communication equipment to the list, of course.

This Robert Zubrin op-ed - How to build a moonbase in four years - should really get the discussion going

Op-ed | Moon Direct: How to build a moonbase in four years - SpaceNews.com:  http://spacenews.com/op-ed-moon-direct-how-to-build-a-moonbase-in-four-years/

 

[Frank]

On 3/16/2018 at 2:06 PM, Area54 said:

Thank you for the clarification although it creates further puzzlement. As far as I am aware the data in the link you provided is for a resuable Falcon Heavy and the price ($90m) takes account of the reduced payload capacity. Consequently my figure of $1.4 million/t is valid. I would aslo dispute your statement that "we can only guess at the price". Space-X have provided a specific price on that link. No guessing is required.

Next point of confusion. (My apologies for not following your argument properly.) Your propellant mining appears to be in relation to the moon, so what is the relevance of placing payload in LEO? Again, I look forward to your clarification.

Finally found the quote for FH partly reusable: Elon Musk on Twitter: "Side boosters landing on droneships & center expended is only ~10% performance penalty vs fully expended. Cost is only slightly higher than an expended F9, so around $95M.… https://t.co/Wx1Q0nS5dr   So $95 million/(63.5*0.9) = $1.66 million/t

Placing payload into LEO is for the closest refuelling point.  Either propellant launched as extra ballast when possible, or ferried from the moon (only works under special circumstances).  I'm thinking meet in the middle as much as possible, maybe (also) a propellant depot at EML-1 or EML-2.

 

[Frank]

"In Situ Heat Shield Fabrication at Phobos/Deimos for Earth-bound Mars Return Spacecraft and Mars EDL of Surface Exploration Craft" - Wow!  If Mars' moons dust composition is similar to our moon's, it means that tech that works on the moon should work (if gravity isn't a factor) on other moons.  So Oxygen production at Mars' moon should also be possible.  Another reason to start a moon base, and another reason to start with oxygen from regolith once there.

Regolith Derived Heat Shield for Planetary Body Entry and Descent System with In Situ Fabrication: https://www.nasa.gov/pdf/744615main_2011-Hogue-Final-Report.pdf

 

[Frank]

Zubrin's moon direct transport plan uses existing tech plus a redo of an Apollo-era Lunar Excursion Module.  It also introduces (to me anyway) a microwave based ice melting and collection scheme.  Basically, a trip to the lunar surface and back requires 2 Falcon heavy launches plus a Falcon-9 launch for crew.  No BFR, no SLS needed.

Moon Direct - Robert Zubrin - International Space Development Conference - Saturday, May 26, 2018 - YouTube: 

 

Discussion on redit:  https://www.reddit.com/r/spacex/comments/8my4tf/moon_direct_robert_zubrin_international_space/

 

Edited June 13, 2018 by Frank