Report: Solutions for Construction of a Lunar Base (Starship as base structure)

[su27k]

https://starship1.onuniverse.com/

The Team Project “Solutions for Construction of a Lunar Base” is the product of 9 intense weeks of collaboration during the Space Studies Program 2021 - Strasbourg, at the International Space University.

Executive Summary: https://drive.google.com/file/d/1WRNi4FlcZ9OuNg00Y-rpQET0nqrMpLzy/view

Report: https://drive.google.com/file/d/1x1ujpGR43BbIr6Bp_hEzYuVFCCp-hYGo/view

IAC-21 Paper: https://drive.google.com/file/d/14IYC0k8-W6ZrS9WXilLuYNw2ZQzItKmj/view

Returning to the Moon and establishing a permanent human presence is the next step in
human space exploration. This necessitates the development of lunar infrastructure capable
of sustaining a permanent human presence. This team presents a supporting framework for
rapid, cost-efficient, and supporting construction of a permanent and modular lunar base within
the scope of what is technically feasible today in space law paradigms.

The proposed lunar base concept uses the SpaceX Starship Human Landing System as base
infrastructure which will be placed horizontally on the lunar surface and transformed into a habitable
volume. A crew of modular rovers will aid astronauts by supporting the construction process.
Countermeasures are presented to protect the astronauts from the effects of exposure to
radiation, lunar dust, extended hypogravity are identified. Psychological and psychosocial factors
are included to enhance individual well-being and crew dynamics. Physical and cognitive
workloads are defined and evaluated to identify countermeasures, including specific spacesuit
parameters.

The construction is to be organized as a multi-national public-private partnership to establish an
international authority, a concept that has been successful on Earth but has yet to be applied
to space activities on a multi-national level. A public relations and communications strategy
built around the value proposition is provided as a way to ensure sustained public, private, and
political support for the project. A roadmap is provided, incorporating each part of the construction
from human and technical perspectives. Other aspects which are critical to mission
success include the cultural significance of the project, legal aspects, developments, budget,
financing, and potential future uses. These solutions rely mainly on existing technologies and
limited modifications to the lunar lander vehicle, making it a viable solution for the construction
of a lunar base in the near future.

[BZHSpace]

The fliping phase will caused some issues IMO.

-> First issue consists in the fixing points on the Lunar soil to support starship during the flip :

How the fixing point will be enough robust for supporting a Starship ?

-> Second issue is about in the Starship motion when it fliped :

How the ground surface will be enough planar to not caused a roll motion of the Starship ?

-> Third issue is about the inner space arrangement :

How will they reconvert the fuel tank into a living space and installed a life support system ?

[nacnud]

How the fixing point will be enough robust for supporting a Starship ?

Google ground anchor. There are lots of options for this including for use in regolith and soils including equalised ground pins, deadman (normally used in snow), glued or mechanical bolts for hard rock etc You'd just need to test and characterise each anchor before determining how many would be needed. You could hold a support at the fulcrum of the tip in the same way.

[SweetWater]

I understand that this is just a study, based on pretty much just the physical dimensions on Starship and some basic requirements of a lunar base, and it isn't an official proposal or anything. That said, I'm not convinced this is the best solution for establishing a lunar base.

It isn't indicated what version of Starship might be used for this or how many engines it might use - the 3x Raptors and 3x vacuum Raptors that are usually shown on renders of the Mars landing version, those with the addition of the ring of lunar landing engines partway up that show up on the HLS version, or something else - but either way the engines are expensive and bulky and useless once the Starship has been converted into a base. I suppose they could be removed and returned to Earth (or at least Earth orbit) to be re-integrated into another Starship, but that would seem to be pretty involved for a quick and dirty solution like this.

As BZHSpace indicated above, moving the Starship to a horizontal position and converting the tankage to living space would present challenges. I don't think there's any reason to think they are insurmountable with sufficient time/money, but they are significant issues to be resolved.

It would be interesting to see a study comparing the possible costs of using Starship to transport purpose-built modules to the moon vs. both the time, money, and labor that would be needed to design a Starship that is intended to be converted into a habitat and then actually launch and convert it.

I do understand that any future lunar base will probably require some crew time for construction. However, if future astronauts' time on EVAs on the lunar surface is limited for dust exposure and radiation concerns, is that time best spent converting a Starship to a habitat vs. using something purpose built that requires less on-site construction?

[nacnud]

I can see the advantage of using expendable landers in this way but to do the same with a reusable lander before it is end of life seems foolish.

Just land your base in multiple 100 ton loads until the lander is worn out, then this might be a good idea.

[spacenut]

Starships could be constructed with door plates that can be unbolted from each of the fuel tanks after they are vented to vacuum.  Then repressurized with oxygen/nitrogen atmosphere.  The astronauts can then construct the insides in shirtsleeves making it much easier.  Astronauts on the surface can use excavation equipment to cover with regolith.  This seems easy enough. 

Maybe a special Starship can be built with thrusters to lower it horizontal after landing and even have some small legs along the side to stabilize when lowered.  Also, fresh water and waste water can be stored in the ceiling to add some radiation protection along with the regolith on the outside. 

Purging methane should be easier since it will be lighter than oxygen and nitrogen.  The lox tank wouldn't have to be purged as such, but some nitrogen added to make it less volatile to fires. 

A prebuilt special Starship could well be used.  The engines might be able to be disconnected and brought back on return Starships. 

[Robotbeat]

Starships could be constructed with door plates that can be unbolted from each of the fuel tanks after they are vented to vacuum.  Then repressurized with oxygen/nitrogen atmosphere.  The astronauts can then construct the insides in shirtsleeves making it much easier.  Astronauts on the surface can use excavation equipment to cover with regolith.  This seems easy enough. 

Maybe a special Starship can be built with thrusters to lower it horizontal after landing and even have some small legs along the side to stabilize when lowered.  Also, fresh water and waste water can be stored in the ceiling to add some radiation protection along with the regolith on the outside. 

Purging methane should be easier since it will be lighter than oxygen and nitrogen.  The lox tank wouldn't have to be purged as such, but some nitrogen added to make it less volatile to fires. 

A prebuilt special Starship could well be used.  The engines might be able to be disconnected and brought back on return Starships.

Skylab was supposed to be a wet workshop like this. Where is exploring the literature that NASA has produced for that.

Instead of thrusters, a crane (or pulley and ropes anchored to the ground, far away) would be much better. They will need a crane for all kinds of other stuff. The lower gravity means the crane can be much lighter than on Earth, and they could make it out of carbon fiber struts to reduce weight. NASA Langley has done significant work on that sort of lunar or Mars crane.

[jak Kennedy]

The rocket would flop to the ground uncontrolled without using something like an A frame between the rocket and anchors to increase in height of the pivot point of the cables. I am surprised something so basic was left out.

[DanClemmensen]

I think the mass of a pair of sheer legs would be less than the mass of the anchors and cables, and sheer legs would actually work, while those cables will be at a horrible mechanical disadvantage at the low angle shown.

[oldAtlas_Eguy]

Start with a one way cargo to moon Starship. This cargo Starship would carry 200t of equipment all the way from Earth. This includes all the equipment to lower the Starship horizontally (whatever that may be) as well as everything to outfit it completely. Ending habitat space some approximately 2500m^3. Other items such as ground vehicles and regolith(earth) movers would be shipped by another method since they have more usage than for just this task/end item. Depending on leftover payload mass capability as much solar array hardware as will fit to make up the total of 200t. Else the solar array farm would be shipped separately and setup likely in stages some prior and other parts after the specialty cargo Starship arrival.

Specifics as to what the exact hardware for the tip over and cradles would be is simple engineering to come up with a solution that is easy to implement as well as moderate to low mass. KISS

One of the primary tools to include is a stainless steel welder that operates in vacuum. The three side entrances are shipped as compact sets of stainless steel that just need a few bolts to hold their shape while seal welds are made with the welder. Airlocks that are very large can be constructed simply in vacuum such that large 3mX3m size containers can be swapped in and out of the habitat. This is so that it is easy to not only resupply the habitat but to throw out the trash.

The habitat volume would support a crew size of 30 such that about every 3 months a total of 5 such containers 45m^3 would be being swapped in and out of the habitat. Think about what you would need in containers if you could only get a 1m cube container in and out it would take 45 such containers in and out of the airlocks to resupply the habitat. You need at lest 1 very large airlock. You are not going to ship a prebuilt airlock that large or likely even one that is smaller. Such would have to be constructed and attached to the three points. An extra internal dome bulkhead with a large 3mX3m airlock door so that the space can be sealed up to cut a 3mX3m opening in the LCH dome to then attach another door to make a temporary airlock so that the pressure tight tanks can be quickly set up as habitats and large equipment containers of equipment to be installed can be moved from the Starship payload section into the tanks sections.

Lots of things and lots of careful procedure steps orchestration to be able to handle vacuum and pressurized volumes without loosing all of the gasses that may be useful. Plus also the packing of the payload space so that items are accessible in the order in which they would be used. It is not just the hardware designs but also designing it for being able to be manipulated and installed on the Moon. Prior to anything like this would be a simple HLS Lunar Starship that is landed and used as is without any modifications for a habitat until a larger more highly usable solution is devised.

[DreamyPickle]

It would be interesting to see a study comparing the possible costs of using Starship to transport purpose-built modules to the moon vs. both the time, money, and labor that would be needed to design a Starship that is intended to be converted into a habitat and then actually launch and convert it.

Purpose build modules would have a volume much smaller than the full Starship and one-way flights to the moon would also require fewer refueling flights. If optimizing dollars per pressurized volume then expending starships (and optionally returning engines) would probably win by a factor of 5 or 10.

It's not clear that pressurized volume would be a major limitation, indeed a single permanently landed Starship would be sufficient as a permanent base by itself. Keeping all of that volume habitable over the lunar night would be a major challenge, even if all you use it is as a garage or for growing plants.

I think we are likely to see many one-way flights carrying only cargo so the ground around the base will end up littered with empty starships anyway which will eventually be scrapped.

[Oersted]

When asked about laying down Starship on its side on the Moon, Elon tweeted "no". Why do people keep going back to this harebrained idea?

[AC in NC]

When asked about laying down Starship on its side on the Moon, Elon tweeted "no". Why do people keep going back to this harebrained idea?

It makes me insane.   

You know what's absolutely required to construct a Lunar Base using 2 PY's of Fully Burdened Lunar Astronaut Labor over 6 months?  Answer:  A Lunar Base.   

Why one would waste those PY's to turn one lunar base into another lunar base totally escapes me.  It's a subject ripe for the "Eliminate Dumb Requirements" analysis.

[AU1.52]

When asked about laying down Starship on its side on the Moon, Elon tweeted "no". Why do people keep going back to this harebrained idea?

It makes me insane.   

You know what's absolutely required to construct a Lunar Base using 2 PY's of Fully Burdened Lunar Astronaut Labor over 6 months?  Answer:  A Lunar Base.   

Why one would waste those PY's to turn one lunar base into another lunar base totally escapes me.  It's a subject ripe for the "Eliminate Dumb Requirements" analysis.

Let an unmanned Starship dig its own hole on landing and then cover it with regolith with it still upright!

[volker2020]

When asked about laying down Starship on its side on the Moon, Elon tweeted "no". Why do people keep going back to this harebrained idea?

The question was answered in regard to the normal landing of Starship on the moon, and as Elon tweeted it does not make any sense.
This proposal is about the cheapest way, to build a large moon station with enough radiation shielding by digging it in.
I would judge not exactly the same use case.

[AC in NC]

When asked about laying down Starship on its side on the Moon, Elon tweeted "no". Why do people keep going back to this harebrained idea?

The question was answered in regard to the normal landing of Starship on the moon, and as Elon tweeted it does not make any sense.
This proposal is about the cheapest way, to build a large moon station with enough radiation shielding by digging it in.
I would judge not exactly the same use case.

No, it was not.

https://twitter.com/elonmusk/status/1298452372704894979

[wheedude]

I understand that this is just a study, based on pretty much just the physical dimensions on Starship and some basic requirements of a lunar base, and it isn't an official proposal or anything. That said, I'm not convinced this is the best solution for establishing a lunar base.

It isn't indicated what version of Starship might be used for this or how many engines it might use - the 3x Raptors and 3x vacuum Raptors that are usually shown on renders of the Mars landing version, those with the addition of the ring of lunar landing engines partway up that show up on the HLS version, or something else - but either way the engines are expensive and bulky and useless once the Starship has been converted into a base. I suppose they could be removed and returned to Earth (or at least Earth orbit) to be re-integrated into another Starship, but that would seem to be pretty involved for a quick and dirty solution like this.

...

I agree with much of this.  I don't see a point in tipping over a starship to create a permanent habitat.  I do however see value in salvaging engines in this manner.  Could be useful if you find a recently landed Starship has an engine anomaly torn fuel line or something.  If society/NASA/SpaceX/Other Agencies are serious about returning to the moon and establishing any sort of permanent presence, maintenance of long term equipment/reusable landers is going to be a key issue.  While an established base could possibly wait for new parts/supplies to be sent, having the ability to perform some repairs or equipment swap-outs will be huge.  I realize lunar regolith presents a problem, but surely someone can find ways to clean off/strip parts for reuse.  Maybe a well used cargo starship could be stripped for parts and scrap metal after it's last landing (or if one should suffer a landing accident and not be able to take off again).  Just like using local lunar resources will be a game changer for fueling/water/manned spaceflight; reusing/repurposing junk/crashed equipment and will eventually prove worthwhile. 

[gpm]

It isn't indicated what version of Starship might be used for this or how many engines it might use - the 3x Raptors and 3x vacuum Raptors that are usually shown on renders of the Mars landing version, those with the addition of the ring of lunar landing engines partway up that show up on the HLS version, or something else - but either way the engines are expensive and bulky and useless once the Starship has been converted into a base. I suppose they could be removed and returned to Earth (or at least Earth orbit) to be re-integrated into another Starship, but that would seem to be pretty involved for a quick and dirty solution like this.

Expensive? 6 raptors should cost less than 2 million dollars new. I can't imagine removing them and returning them to earth will be cheaper than that: https://twitter.com/elonmusk/status/1420826978102435845?s=21

Bulky? They're outside on the moon, you have an entire celestial body, a few extra engines aren't going to be in the way.

Useless - maybe - but you needed them to get you there. wheedude points out that they might be useful as spare parts. I'd add that if nothing else they're scrap metal that can easily be recycled into something else.

I don't think returning them to earth makes sense as an end goal.

[Oersted]

3) This seems to be a student paper, so maybe we could be a little understanding of that.

University students, supposedly.

I'd say suggesting horizontal Starships would be grounds for immediate remedial training in Physics 101.

[geekesq]

I don't see a point in tipping over a starship to create a permanent habitat.  I do however see value in salvaging engines in this manner.  Could be useful if you find a recently landed Starship has an engine anomaly torn fuel line or something.

I think it would be easier to de-engine (and re-engine) a Starship the way they do it on Earth: with the Starship vertical on a stand.  For that, you ship to the moon and assemble the lunar equivalent of an LR11000 crawler crane -- which would have a lot of other uses.

[wheedude]

I don't see a point in tipping over a starship to create a permanent habitat.  I do however see value in salvaging engines in this manner.  Could be useful if you find a recently landed Starship has an engine anomaly torn fuel line or something.

I think it would be easier to de-engine (and re-engine) a Starship the way they do it on Earth: with the Starship vertical on a stand.  For that, you ship to the moon and assemble the lunar equivalent of an LR11000 crawler crane -- which would have a lot of other uses.

Kind of what I'm saying... definitely would need some sort of crane or pad lift setup eventually either way.  While a fresh engine would be best, salvaged spares (and their plumbing/mounts/literal nuts and bolts) still have value. 

[kevindbaker2863]

Since  HLS  is going to send a test flight to the moon anyway and could use a payload? maybe these guys (ICON)https://www.iconbuild.com/technology/space would want to create an automated system to build a habitat that fits inside the HLS?  with enough resin to mix with lunar regolith to get a test of the system? then NASA would pay them to build habitats that were proven to work.  they build product get a free ride and everyone wins?

[daveklingler]

I can see the advantage of using expendable landers in this way but to do the same with a reusable lander before it is end of life seems foolish.

Just land your base in multiple 100 ton loads until the lander is worn out, then this might be a good idea.

There's a factory in Boca Chica producing lunar and orbital habs at the rate of about one a month.  Kudos to SpaceX for cleverly making sure the design doubles as a rocket.

Seriously, when it's relatively straightforward to build a big enclosed space by leaving a rocket on the lunar surface, why not?  What would you propose be done with those multiple 100t (or 200t) loads? 

Remember, if you set out to design a purpose-built hab from scratch, it will most likely not be mass-produced or optimized in any other way for cost or speed of fabrication.  How many years would it take for NASA to issue an RFP for a hab (presumably that fits aboard a Starship), then review proposals, then fund a few, then weather the ensuing protests, then finally launch the thing? 

In the mean time, Starship Canolunis (my preferred name) could be completed and functional.

Admittedly, if we find a likely-looking lava tube, we may need to have some future class do a design study on sealing it off and designing an airlock for it, as that could be even easier.

[kevindbaker2863]

I can see the advantage of using expendable landers in this way but to do the same with a reusable lander before it is end of life seems foolish.

Just land your base in multiple 100 ton loads until the lander is worn out, then this might be a good idea.

There's a factory in Boca Chica producing lunar and orbital habs at the rate of about one a month.  Kudos to SpaceX for cleverly making sure the design doubles as a rocket.

Seriously, when it's relatively straightforward to build a big enclosed space by leaving a rocket on the lunar surface, why not?  What would you propose be done with those multiple 100t (or 200t) loads? 

Remember, if you set out to design a purpose-built hab from scratch, it will most likely not be mass-produced or optimized in any other way for cost or speed of fabrication.  How many years would it take for NASA to issue an RFP for a hab (presumably that fits aboard a Starship), then review proposals, then fund a few, then weather the ensuing protests, then finally launch the thing? 

In the mean time, Starship Canolunis (my preferred name) could be completed and functional.

Admittedly, if we find a likely-looking lava tube, we may need to have some future class do a design study on sealing it off and designing an airlock for it, as that could be even easier.

looks like you could fit 2 of these in a SS and have lots of room to spare?  https://www.aispacefactory.com/marsha

[Ionmars]

Moon base 10-30—21

To see why a lunar or Mars base proposal might include Starship shells (cargo sections and propellant tanks) , it may be helpful to review the components of base construction.

1. Habitats will be pressurized enclosures, usually in round shapes that emulate pressurized containers on Earth. Globes or cylinders with rounded ends are efficient for this purpose.

2. Habitats will require protection from solar and galactic radiation and meteorites. This will usually entail ground cover or underground construction.

3. A base or colony will encompass a variety of structures used as homes and workplaces with earth-like air pressure and temperature control.

4. Habs will include airlocks for access to and from the exterior surface.

5. For efficient operation, habs should be interconnected with hallways that contain the same air environment as habs. This avoids frequent use of airlocks where much time would be consumed donning and un-donning spacesuits.

Using these basic principles, it is natural to consider SS shells as base components to fill some of these requirements at low cost. A landed starship with pressurized crew space is already a habitat. A landed starship with pressurized cargo space can be unloaded and reused as habitat volume. Also, each SS provides ready-made tanks for storing cryogenic liquids.

ISTM these metal cylinders may also be as hallways.

Before you go crazy, please consider that these lightweight cylinders lying in horizontal position would not be employed as structures by themselves,  but as frameworks for constructing chambers around them. One would begin by pushing loose regolith under the bottom side of the cylinder and compressing it into place. If necessary,  a small amount of epoxy resin could be mixed with regolith to ensure hardness (or water if the site is shaded). Regolith fill consisting of sand and rock would be built up along the sides and compacted, then continued over the top of the cylinder. The object is to build a self-supporting structure with an interior steel shell to provide the pressurized volume. Additional framework inside the cylinder would provide support for floors and walls.

However, if you love Starship for its tall beautiful shape alone, then no engineering requirement will justify its placement in horizontal position.

Edit: spelling

[Ludus]

Since  HLS  is going to send a test flight to the moon anyway and could use a payload? maybe these guys (ICON)https://www.iconbuild.com/technology/space would want to create an automated system to build a habitat that fits inside the HLS?  with enough resin to mix with lunar regolith to get a test of the system? then NASA would pay them to build habitats that were proven to work.  they build product get a free ride and everyone wins?

I could be wrong, but based on commercial crew contracts I think after fulfilling the Artemis contract requirements to land on the moon once, SpaceX will own both fully reusable Artemis Starships outright and they will form part of a lunar transport infrastructure along with the Dear Moon Starship and the established refilling capacity using cargo/tanker Starships.

NASA controls whatever is on them the first time and can do as it pleases but is unlikely to further complicate the missions.

Since SpaceX plans to keep making Starships in quantity, it makes sense that a permanent base proposal like this would involve ordering several more Starship variants built to these design specs.

Systems for making structures out of regolith based concrete would likely be added in at some point since this design requires shaping regolith around airlock entrances and of course at launch and landing pads. If they worked well they’d have clear use as the base grows.

[Ludus]

When asked about laying down Starship on its side on the Moon, Elon tweeted "no". Why do people keep going back to this harebrained idea?

The question was answered in regard to the normal landing of Starship on the moon, and as Elon tweeted it does not make any sense.
This proposal is about the cheapest way, to build a large moon station with enough radiation shielding by digging it in.
I would judge not exactly the same use case.

No, it was not.

https://twitter.com/elonmusk/status/1298452372704894979

That’s a pretty unambiguous answer, but it’s still not obvious what the reasons are. Elon’s thinking on a lot of things has evolved over time.

Do you think the basis is structural, that Starship is just not designed to handle loads horizontally for use like this, even in Lunar gravity? That tinkering with this is not worth the effort required?

[punder]

Older renderings of Starship on its way to Mars showed a fan-shaped solar array near the base. I’ve wondered where this array is stowed; I think it will require a long, narrow aerocover along the leeward side.

Anyways. Lunar Starships could deploy this array for the cruise to the Moon, stow it for landing, then deploy it again—permanently—after landing.

So each permanent “hab” Starship brings its own power as a matter of course, eliminating or at least decreasing the need for arrays carried as cargo that must be unshipped, transported, erected and cabled.

Just a thought.

Edit, heh. Completely forgot the wraparound array on the LS nose. NEVERMIND!

[AC in NC]

That’s a pretty unambiguous answer, but it’s still not obvious what the reasons are. Elon’s thinking on a lot of things has evolved over time.

Do you think the basis is structural, that Starship is just not designed to handle loads horizontally for use like this, even in Lunar gravity? That tinkering with this is not worth the effort required?

Basically "Yes" to the bolded question.  The question posed to Elon cannot be answered as unequivocally as he did because SS clearly "would" be able to lay down given sufficient effort and adaptation. 

Truthful interpretations of what he meant by "No" are:

1)  "No, Not AS-IS. It would require adaptation" 
2)  "No, are you insane?  The notion is specious.  The amount of work would be off-the-charts not worth it"

Assuming the Questioner meant (1) seems sort of Strawman-ish, so I think (2) is what he meant.

Personally, I think people improperly handwave away and totally underestimate how difficult and time-consuming it will be to accomplish things like this off-earth for a long, long time.

[Alberto-Girardi]

When asked about laying down Starship on its side on the Moon, Elon tweeted "no". Why do people keep going back to this harebrained idea?

The question was answered in regard to the normal landing of Starship on the moon, and as Elon tweeted it does not make any sense.
This proposal is about the cheapest way, to build a large moon station with enough radiation shielding by digging it in.
I would judge not exactly the same use case.

No, it was not.

https://twitter.com/elonmusk/status/1298452372704894979

That’s a pretty unambiguous answer, but it’s still not obvious what the reasons are. Elon’s thinking on a lot of things has evolved over time.

Do you think the basis is structural, that Starship is just not designed to handle loads horizontally for use like this, even in Lunar gravity? That tinkering with this is not worth the effort required?

I would like a lot to see SS used to construc a lunar base, but I think that Elon response wasn't a joke, and knowing how Spacex is innovtive the answer makes me quite sure that they won't do that. But the final word isn't said.

[Ionmars]

When asked about laying down Starship on its side on the Moon, Elon tweeted "no". Why do people keep going back to this harebrained idea?

The question was answered in regard to the normal landing of Starship on the moon, and as Elon tweeted it does not make any sense.
This proposal is about the cheapest way, to build a large moon station with enough radiation shielding by digging it in.
I would judge not exactly the same use case.

No, it was not.

https://twitter.com/elonmusk/status/1298452372704894979

That’s a pretty unambiguous answer, but it’s still not obvious what the reasons are. Elon’s thinking on a lot of things has evolved over time.

Do you think the basis is structural, that Starship is just not designed to handle loads horizontally for use like this, even in Lunar gravity? That tinkering with this is not worth the effort required?

I believe Elon will eventually reconsider because there is a strong argument for employing SS hulls in the pioneering stages of a new base..

[AstroWare]

When asked about laying down Starship on its side on the Moon, Elon tweeted "no". Why do people keep going back to this harebrained idea?

The question was answered in regard to the normal landing of Starship on the moon, and as Elon tweeted it does not make any sense.
This proposal is about the cheapest way, to build a large moon station with enough radiation shielding by digging it in.
I would judge not exactly the same use case.

No, it was not.

https://twitter.com/elonmusk/status/1298452372704894979

That’s a pretty unambiguous answer, but it’s still not obvious what the reasons are. Elon’s thinking on a lot of things has evolved over time.

Do you think the basis is structural, that Starship is just not designed to handle loads horizontally for use like this, even in Lunar gravity? That tinkering with this is not worth the effort required?

I believe Elon will eventually reconsider because there is a strong argument for employing SS hulls in the pioneering stages of a new base..

I think most of the objections are to putting a starship HORIZONTAL. Not that suppose can't be used for long periods of time on the surface as part of a base.

From an engineering and logistics perspective, It's more than just tinkering. I think that was why Elon responded the way he did.

From a more fundamental perspective, why? I think you (and others) are trying to find reasons that bases should be made of horizontal cylinders. There are plenty of advantages to keeping the ships vertical besides structural.

Sent from my Pixel 5a using Tapatalk

[Okie_Steve]

Here is an off the wall question. If we hand wave that ballooning the tanks will prevent buckling and collapse, how much oomph would the RCS need to:

1) Tip Starship over

2) Limit the angular momentum to something "safe"

 

Edit - Tongue well out in cheek since I actually agree with the previous post. Why mess with curved floors etc in a gravity well?

[AC in NC]

Just tip the Starship over, then have the astronauts from the Blue Origin Lander transit over to a Starship horizontally. 

This solves a lot of issues for both HLS concepts.  Especially the ladder issue with the Blue Origin HLS Lander as well as the tip over/vertical stability issue with the Starship.

Centuries from now, this will be another site as marvelous as the ancient pyramids.

"Just [fill in the blank]" is almost always a major, major red flag. 

I can't help but think you are joking with this nonsense.  Look at what you did:  You "solved" arguably non-existent (or easily solvable) issues with something super challenging with extraordinarily limited benefit.

[volker2020]

There are 3 basic questions:

a) Has a horizontal cylinder advantages over a vertical one?
The answer is a clear yes. You can dig it in much easier to give radiation shielding, and you don't need lifts to enter.

b) Would it be possible, to bring a Starship into horizontal orientation?
Again, the answer is a clear yes. With a minimal adapted Starship (Having some hardpoints, worst case some structural reinforcements and suitable winches on the ground, it is clearly possible.

c) Is it easier to use a dig in horizontal Starship, than build the base using other prefabricated parts, or let is stay vertically?
Tougher question. That clearly depends on the radiation protection that you envisage. If you claim that  a standard Spaceship has enough protection for a long term stay, why spend time with it. If not I assume that it would be easier to create a base using a salvaged Starship. For sure that is no question, that you can easily solve with a No, so I doubt that this was, what Elon had in mind, when he gave that answer. But what I totally agree with, would be saying, that bringing Starship horizontally will never be standard procedure.

[tenkendojo]

There are 3 basic questions:

a) Has a horizontal cylinder advantages over a vertical one?
The answer is a clear yes. You can dig it in much easier to give radiation shielding, and you don't need lifts to enter.

Based on current scientific evidence concerning radiation risks for human missions on the lunar surface, I do not share this widespread impulse towards horizontality and "bury under rocks/regolith" approach to lunar surface base design.

We have very interesting results from the Germany's Lunar Lander Neutron and Dosimetry (LND) onboard the Chang'e 4 lander, which measures simulated equivalent of hourly radiation exposure of human in EVA suit on lunar surface. See here for the published study: https://link.springer.com/epdf/10.1007/s11214-020-00725-3?sharing_token=yM0G6YRGkeahID9_CL-LV_e4RwlQNchNByi7wbcMAY4KW2Ew4jw801Oflt5mNq37bh9zawC-7RQo2hqPn4gELrSWmoHiMETDQYVkdzno21dJkw4BY4ZYsMtodj7Wd3bvfoTEGYVJ1wYUOP6VLT6jZcCph1NK9Dq3i8hrt8Lrcsg%3D

So based on data from the LND instruments, we have calculated the 'equivalent dose' of an astronaut working on the lunar surface to be about 60 microsieverts of radiation per hour. Note that this number reflects the per hour exposure approximation while working outside with protection of the EVA suit only. This number is only about 5-8 times higher than the radiation exposure we get from a transatlantic flight. At 60 microsieverts per hour, an astronaut could spend almost two years, just with EVA suit level radiation protection, on the lunar surface before violating the current lifetime exposure limit. That's why I think the actual radiation risks for lunar surface base do not warrant horizontal and buried habitat architecture.

[AC in NC]

"Just [fill in the blank]" is almost always a major, major red flag. 

I have to admit, I don't know how all of these habitats and rovers arrive in the conceptss over the ages (by November 2029).  Somehow, they just reorient from a vertical lander into the horizontal configuration.

Because they are "conceptions" which is basically synonymous with "fiction".  Go back and figure out how they reorient and you'll have the answer to why "just" is so disingenuous.

[livingjw]

If water is available on the Moon, a water wall on a vertical Lunar Starship might be easier. If there isn't any water mining going on, I doubt we will have a large permanent base.

John

[volker2020]

There are 3 basic questions:

a) Has a horizontal cylinder advantages over a vertical one?
The answer is a clear yes. You can dig it in much easier to give radiation shielding, and you don't need lifts to enter.

Based on current scientific evidence concerning radiation risks for human missions on the lunar surface, I do not share this widespread impulse towards horizontality and "bury under rocks/regolith" approach to lunar surface base design.

We have very interesting results from the Germany's Lunar Lander Neutron and Dosimetry (LND) onboard the Chang'e 4 lander, which measures simulated equivalent of hourly radiation exposure of human in EVA suit on lunar surface. See here for the published study: https://link.springer.com/epdf/10.1007/s11214-020-00725-3?sharing_token=yM0G6YRGkeahID9_CL-LV_e4RwlQNchNByi7wbcMAY4KW2Ew4jw801Oflt5mNq37bh9zawC-7RQo2hqPn4gELrSWmoHiMETDQYVkdzno21dJkw4BY4ZYsMtodj7Wd3bvfoTEGYVJ1wYUOP6VLT6jZcCph1NK9Dq3i8hrt8Lrcsg%3D

So based on data from the LND instruments, we have calculated the 'equivalent dose' of an astronaut working on the lunar surface to be about 60 microsieverts of radiation per hour. Note that this number reflects the per hour exposure approximation while working outside with protection of the EVA suit only. This number is only about 5-8 times higher than the radiation exposure we get from a transatlantic flight. At 60 microsieverts per hour, an astronaut could spend almost two years, just with EVA suit level radiation protection, on the lunar surface before violating the current lifetime exposure limit. That's why I think the actual radiation risks for lunar surface base do not warrant horizontal and buried habitat architecture.

One of the authors did come to another conclusion:
from https://phys.org/news/2020-09-moon.html:

Astronauts would get 200 to 1,000 times more radiation on the moon than what we experience on Earth—or five to 10 times more than passengers on a trans-Atlantic airline flight, noted Robert Wimmer-Schweingruber of Christian-Albrechts University in Kiel, Germany.

"The difference is, however, that we're not on such a flight for as long as astronauts would be when they're exploring the moon," Wimmer-Schweingruber said in an email.

Cancer is the primary risk.

"Humans are not really made for these radiation levels and should protect themselves when on the moon," he added.

[tenkendojo]

There are 3 basic questions:

a) Has a horizontal cylinder advantages over a vertical one?
The answer is a clear yes. You can dig it in much easier to give radiation shielding, and you don't need lifts to enter.

Based on current scientific evidence concerning radiation risks for human missions on the lunar surface, I do not share this widespread impulse towards horizontality and "bury under rocks/regolith" approach to lunar surface base design.

We have very interesting results from the Germany's Lunar Lander Neutron and Dosimetry (LND) onboard the Chang'e 4 lander, which measures simulated equivalent of hourly radiation exposure of human in EVA suit on lunar surface. See here for the published study: https://link.springer.com/epdf/10.1007/s11214-020-00725-3?sharing_token=yM0G6YRGkeahID9_CL-LV_e4RwlQNchNByi7wbcMAY4KW2Ew4jw801Oflt5mNq37bh9zawC-7RQo2hqPn4gELrSWmoHiMETDQYVkdzno21dJkw4BY4ZYsMtodj7Wd3bvfoTEGYVJ1wYUOP6VLT6jZcCph1NK9Dq3i8hrt8Lrcsg%3D

So based on data from the LND instruments, we have calculated the 'equivalent dose' of an astronaut working on the lunar surface to be about 60 microsieverts of radiation per hour. Note that this number reflects the per hour exposure approximation while working outside with protection of the EVA suit only. This number is only about 5-8 times higher than the radiation exposure we get from a transatlantic flight. At 60 microsieverts per hour, an astronaut could spend almost two years, just with EVA suit level radiation protection, on the lunar surface before violating the current lifetime exposure limit. That's why I think the actual radiation risks for lunar surface base do not warrant horizontal and buried habitat architecture.

One of the authors did come to another conclusion:
from https://phys.org/news/2020-09-moon.html:

Astronauts would get 200 to 1,000 times more radiation on the moon than what we experience on Earth—or five to 10 times more than passengers on a trans-Atlantic airline flight, noted Robert Wimmer-Schweingruber of Christian-Albrechts University in Kiel, Germany.

"The difference is, however, that we're not on such a flight for as long as astronauts would be when they're exploring the moon," Wimmer-Schweingruber said in an email.

Cancer is the primary risk.

"Humans are not really made for these radiation levels and should protect themselves when on the moon," he added.

I am not suggesting radiation isn't considered a risk, but our unserstanding of radiation risk must placed in a proper context: what is the nature and function of lunar base? How long should an astronaut expect to stay on the moon for a typical mission to the lunar base? Would the base be more similar to a scientific outpost with a small rotating crew or are we talking about a lunar colony with permanent inhabitants? I agree for permanent lunar colony we absolutely need buried/underground habitats for long term radiation shielding. But we have a long way to go, if ever, to build any permanently inhabitanted lunar colony.

 So for a more realistic lunar base, how long should we expect a typical stay be? Probably from a few months to up to a year maybe, possibly a little longer for exceptional cases. Like I said before, the radiation level would allow most astronauts to work on lunar surface for up to two years without significant health risks. That is more than sufficient in this realistic mission context. If we are letting astronauts to remain on the lunar base for longer than two years, I would be more worried about serious health risks from long exposure to low gravity environment than radiation. Again context matters.

[Robotbeat]

If water is available on the Moon, a water wall on a vertical Lunar Starship might be easier. If there isn't any water mining going on, I doubt we will have a large permanent base.

John

Even with water mining, what are you even doing with the water mining that will save you more money than the base costs to operate?

[daveklingler]

When asked about laying down Starship on its side on the Moon, Elon tweeted "no". Why do people keep going back to this harebrained idea?

https://twitter.com/elonmusk/status/1298452372704894979

I think this answer is very ambiguous, and leaves plenty of room for interpretation.  It's entirely possible that Musk was answering the question, "Would starship be able to lay down..." without giving a lot of detail.  There's no doubt in my mind that a pressurized Starship could be laid down as it is right now, although I think there's a good chance it would collapse if it lost pressure. That will need to be taken into account during modifications, but it's not a showstopper.

Regarding radiation protection, pack the Starship in question with polyethylene Whipple walls, and lay them over the top half after you tip it over. 

[daveklingler]

If water is available on the Moon, a water wall on a vertical Lunar Starship might be easier. If there isn't any water mining going on, I doubt we will have a large permanent base.

John

Even with water mining, what are you even doing with the water mining that will save you more money than the base costs to operate?

Beyond the questionable assumption that water mining is only desirable to offset base costs, let's not get off-topic.

Edit: I'm having trouble imagining a water wall "on" a vertical Starship, so I might need someone to elucidate how that might work.  But I have no trouble imagining how a polyethylene shield might lay over the top half, with the bottom half protected by regolith.  It's entirely possible that the top half might also be capable of taking the weight of 4 or 5 meters of lunar soil, but that might require a little bit of study (or googling).

[daveklingler]

Regolith is about 1.5g/cm³, so about 1.5t/m³.  Assuming a relatively adequate 5 meters of depth, that's (7.5t/6)/m², or 2750 lbs/39.37² in²= 1.77 psi, which shouldn't affect the structural integrity of a Starship.

In other words, a 5m layer of regolith over the surface of a horizontal Starship should be well within its structural capability. My polyethylene shield is utterly unnecessary.  Just bring an electric bulldozer.  Or plenty of shovels. Maybe both.

I think that the university students have established that a Starship should be straightforward to tip over. Covering it with an adequately-thick layer of soil doesn't seem like much of an issue, and there are plenty of papers out there about installing an airlock on a pressurized tank without losing pressurization. What's left?

[daveklingler]

I think that the university students have established that a Starship should be straightforward to tip over. Covering it with an adequately-thick layer of soil doesn't seem like much of an issue, and there are plenty of papers out there about installing an airlock on a pressurized tank without losing pressurization. What's left?

How precisely did they "establish" that?  What they've asserted below [draining, pressurization, hinge, elevator cables, anchors, scissor lift, piled regolith] is complete and utter handwaving.  They didn't even bother to estimate of what it would take to install one of their anchors.

I don't think they should be required to reinvent mechanical and civil engineering.  Further, various ASCE members have been studying these problems with lunar soil simulants since at least the early eighties.

Klosky, J.L., Sture S., Ko, H.Y. and Barnes, F. (1998). “Helical anchors for combined
anchoring and soil testing in lunar operations.” Proc. Sixth Inter. Conf. Exp.
Engrg, Constr. Op. in Space, pp. 489-494.
McKay, D.S. (2009). “The lunar regolith.” Proc. 70th Anniversary of Hanyang Univ.
Inter. Dist. Scholars Symp. Seven Future Tech., June 11, Seoul, Korea.
Murray E.J. and Geddes J.D. (1987). “Uplift of anchor plates in sand.” J.
Geotechnical Engineering, Vol. 113 (3), pp. 202-215.
Zacny, K. (2009). “Lunar excavation and mining.” Proc.of the 2009 Dasan
Conference – Space Development and Exploration, Oct. 7, Ansan, Korea.
Chang Byung Chul, Bernold, Leonhard E. and Lee, Tai Sik (2010). Pro. 12th Biennial International Conference on Engineering, Construction, and Operations in Challenging Environments and the 4th NASA/ARO/ASCE Workshop on Granular Materials in Lunar and Martian Exploration. Experimental Study of Lunar Regolith Anchoring Forces. pp. 1418 - 1422.

What's left?  Give the task to 12 guys somewhere comparable and see if they can do it without the burden of pressure suits but using the kinds of equipment they would be required to use on the moon.

A demonstration is well beyond the scope of the study and well beyond the means of a handful of university students, not to mention well beyond any reasonable requirement.  The paper also proposed "MORACAS", purposed-designed robots, for the task, so it's not reasonable to ask a dozen guys to borrow a Starship and presumably take video. 

If you just want to see people manipulating Starships, you might look at the Boca Chica threads. 
If you want to watch civil engineers do their stuff, go watch a construction project. 

And if you want more enlightening reading in the same vein as this discussion, check out some of the thousands of papers from the ASCE since the first 1988 ASCE Space: Engineering, Construction and Operations in Space Conference in Albuquerque. Be sure to hit papers by TD Lin, David McKay and Larry Taylor, not to mention Leonhard Bernold's many papers on electric bulldozers for lunar development.

3.3 Horizontalization

Once the MOROCAS have deployed the external systems and drained the excess fuels, the load on the vehicle will be reduced significantly as it is being tilted. The pressure inside the vehicle will be high enough to maintain structural integrity but low enough to reduce the vehicle’s unnecessary mass. The horizontalization system will have several elements and concepts that are designed to reduce the load on the vehicle at different angles of tilt (Fig. 4). A hinge mechanism will be installed by the MOROCAS to prevent the vehicle from slipping and ensure the vehicle is being tilted in the appropriate direction. The cables of the elevators (seen in Fig. 2) coming down from the airlock will be disconnected from the platform and connected to anchors. These cables will carry most of the load on the vehicle at the earlier stages of the tilting procedure. A scissor lift mechanism will be deployed to transfer some of the loads to the ground on the last phase of the process. The vehicle will settle between two parallel ridges of piled regolith to prevent it from rolling and to support the horizontal structure.

Edit: Hey, you deleted your post.  Well...heck.

[AC in NC]

Edit: Hey, you deleted your post.  Well...heck.

Sorry about that.  Prematurely panicked.  I was reading their entire IAC paper (not impressed) and then realized I'd missed that they had another entire 100+ page paper.  Went back to review that and again, totally not impressed (not even a full page on horizontalization).  They say absolutely nothing meaningful about how any of this gets done.  Just a magical "invent a MOROCAS" and it all works (and works with a Single Drill Bit).

You've quoted the text that I deleted so the record is there.

No, they don't need to reinvent mechanical and civil engineering.  But when you don't cite anything meaningful as to engineering figures (as done a hundred times per week in posts here), the paper essentially boils down to a idea that could've been covered in a paragraph or two.  About all they've got is an Appendix Table on Cable Tension that they cite as requiring their Scissor Lift.

If you just want to see people manipulating Starships, you might look at the Boca Chica threads. 
If you want to watch civil engineers do their stuff, go watch a construction project. 

I want to see someone attempt a proposed task or two on earth using similar equipment as proposed.  That's not happening at Boca.  And were it to happen (let's do a thought exercise), I think we would readily see that a handful of guys and robots ain't accomplishing that task in anything like the proposed timeline even under benign earth conditions.

There's no doubt it could be done.  The entire exercise lacks a critical look at whether all the effort necessary to make it doable is worth it.  Despite the propaganda about a "novel look" at "reusability", the entire exercise reeks of old-space.  A New Space approach would be to conceptualize SS-enabled version of an Intermodal Container that could be readily unloaded, and Lego-ized into a base to be covered.

[DistantTemple]

There are 3 basic questions:

a) Has a horizontal cylinder advantages over a vertical one?
The answer is a clear yes. You can dig it in much easier to give radiation shielding, and you don't need lifts to enter.

Based on current scientific evidence concerning radiation risks for human missions on the lunar surface, I do not share this widespread impulse towards horizontality and "bury under rocks/regolith" approach to lunar surface base design.

We have very interesting results from the Germany's Lunar Lander Neutron and Dosimetry (LND) onboard the Chang'e 4 lander, which measures simulated equivalent of hourly radiation exposure of human in EVA suit on lunar surface. See here for the published study: https://link.springer.com/epdf/10.1007/s11214-020-00725-3?sharing_token=yM0G6YRGkeahID9_CL-LV_e4RwlQNchNByi7wbcMAY4KW2Ew4jw801Oflt5mNq37bh9zawC-7RQo2hqPn4gELrSWmoHiMETDQYVkdzno21dJkw4BY4ZYsMtodj7Wd3bvfoTEGYVJ1wYUOP6VLT6jZcCph1NK9Dq3i8hrt8Lrcsg%3D

So based on data from the LND instruments, we have calculated the 'equivalent dose' of an astronaut working on the lunar surface to be about 60 microsieverts of radiation per hour. Note that this number reflects the per hour exposure approximation while working outside with protection of the EVA suit only. This number is only about 5-8 times higher than the radiation exposure we get from a transatlantic flight. At 60 microsieverts per hour, an astronaut could spend almost two years, just with EVA suit level radiation protection, on the lunar surface before violating the current lifetime exposure limit. That's why I think the actual radiation risks for lunar surface base do not warrant horizontal and buried habitat architecture.

One of the authors did come to another conclusion:
from https://phys.org/news/2020-09-moon.html:

Astronauts would get 200 to 1,000 times more radiation on the moon than what we experience on Earth—or five to 10 times more than passengers on a trans-Atlantic airline flight, noted Robert Wimmer-Schweingruber of Christian-Albrechts University in Kiel, Germany.

"The difference is, however, that we're not on such a flight for as long as astronauts would be when they're exploring the moon," Wimmer-Schweingruber said in an email.

Cancer is the primary risk.

"Humans are not really made for these radiation levels and should protect themselves when on the moon," he added.

I am not suggesting radiation isn't considered a risk, but our unserstanding of radiation risk must placed in a proper context: what is the nature and function of lunar base? How long should an astronaut expect to stay on the moon for a typical mission to the lunar base? Would the base be more similar to a scientific outpost with a small rotating crew or are we talking about a lunar colony with permanent inhabitants? I agree for permanent lunar colony we absolutely need buried/underground habitats for long term radiation shielding. But we have a long way to go, if ever, to build any permanently inhabitanted lunar colony.

 So for a more realistic lunar base, how long should we expect a typical stay be? Probably from a few months to up to a year maybe, possibly a little longer for exceptional cases. Like I said before, the radiation level would allow most astronauts to work on lunar surface for up to two years without significant health risks. That is more than sufficient in this realistic mission context. If we are letting astronauts to remain on the lunar base for longer than two years, I would be more worried about serious health risks from long exposure to low gravity environment than radiation. Again context matters.

Ideally space workers of the near future should not be using up their lifetime exposure limit too fast. To have to retire to Earth after a few years work, just when their skills and experience would qualify them to take leading roles on Mars missions etc.! This is not emergency work, its a career. Spending $ and effort on a bit of shielding is part of a commitment to the astronauts, their profession, and confidence in the coming expansion.

[livingjw]

If water is available on the Moon, a water wall on a vertical Lunar Starship might be easier. If there isn't any water mining going on, I doubt we will have a large permanent base.

John

Even with water mining, what are you even doing with the water mining that will save you more money than the base costs to operate?

Beyond the questionable assumption that water mining is only desirable to offset base costs, let's not get off-topic.

Edit: I'm having trouble imagining a water wall "on" a vertical Starship, so I might need someone to elucidate how that might work.  But I have no trouble imagining how a polyethylene shield might lay over the top half, with the bottom half protected by regolith.  It's entirely possible that the top half might also be capable of taking the weight of 4 or 5 meters of lunar soil, but that might require a little bit of study (or googling).

I was envisioning a polyethylene wall or curtain designed to contain water around the inside walls. Once landed it is filled with Lunar sourced water.

John

[Ionmars]

SS landing to base site

When deploying SS as a component of an initial moon base there will be engineering problems to solve along the way. One of these will be the transit of the SS from its landing site to the planned base location.

If we are just visiting the moon to show how it can be done, there is no need to transit anywhere; the landing site will be the base site for just one Starship. However, landing two or more ships to construct a base introduces more considerations. There will be a landing site and a base site separated by a safe distance because the plume of a Raptor during landing will discharge a significant amount of loose regolith and propel it at high speed in all directions. The safe distance between facilities will be determined by what measures are taken to protect personnel and equipment that are already landed. For example, equipment could be covered or buried in regolith before a second landing. Or a berm could be built around equipment to intercept debris flying horizontally. Or a berm could be built around the landing area for the same reason. Or equipment and the base itself could be located in a small crater so the sides of the crater could serve as a natural berm to intercept flying particles. Or the landing site could be located inside a small crate for the same reason. But before we jump on one of these solutions we should also consider relative elevations.

The SpaceX development site at Boca Chica may exemplify the elevation problem. When an SPMT carrying a Starship or propellant cylinder is moved from the production site onto State Highway 4 it is a smooth transition because SpX engineers had the foresight to build the surface of the production area to be the same elevation as the existing highway. The same is true at the intersection of Highway 4 with the launch area. Now consider how these smooth transitions could be accomplished on the Moon, between a landing site and a base site. This will involve building a smooth roadway between two areas with potential changes in elevation.

The design of the roadway between landing site and base will be affected by the choice of moving SS in vertical or horizontal position. Using SPMTs or equivalent to carry SS vertically will require a relatively smoother road surface with few or no abrupt bumps or dips and with modest slope. OTOH carrying SS horizontally will require clearing or avoiding boulders to a distance of 25m or more on both sides of the road.

The transit problem is one of many to address when planning a Moon base. Every decision affects every other decision about how to proceed. Both horizontal and vertical positioning affects everything and both approaches have advantages and disadvantages along the way. It will be helpful to plan the entire base-building process in some detail before committing to any one option.

[DanClemmensen]

SS landing to base site

When deploying SS as a component of an initial moon base there will be engineering problems to solve along the way. One of these will be the transit of the SS from its landing site to the planned base location.

If we are just visiting the moon to show how it can be done, there is no need to transit anywhere; the landing site will be the base site for just one Starship. However, landing two or more ships to construct a base introduces more considerations. There will be a landing site and a base site separated by a safe distance because the plume of a Raptor during landing will discharge a significant amount of loose regolith and propel it at high speed in all directions. The safe distance between facilities will be determined by what measures are taken to protect personnel and equipment that are already landed. For example, equipment could be covered or buried in regolith before a second landing. Or a berm could be built around equipment to intercept debris flying horizontally. Or a berm could be built around the landing area for the same reason. Or equipment and the base itself could be located in a small crater so the sides of the crater could serve as a natural berm to intercept flying particles. Or the landing site could be located inside a small crate for the same reason. But before we jump on one of these solutions we should also consider relative elevations.

The SpaceX development site at Boca Chica may exemplify the elevation problem. When an SPMT carrying a Starship or propellant cylinder is moved from the production site onto State Highway 4 it is a smooth transition because SpX engineers had the foresight to build the surface of the production area to be the same elevation as the existing highway. The same is true at the intersection of Highway 4 with the launch area. Now consider how these smooth transitions could be accomplished on the Moon, between a landing site and a base site. This will involve building a smooth roadway between two areas with potential changes in elevation.

The design of the roadway between landing site and base will be affected by the choice of moving SS in vertical or horizontal position. Using SPMTs or equivalent to carry SS vertically will require a relatively smoother road surface with few or no abrupt bumps or dips and with modest slope. OTOH carrying SS horizontally will require clearing or avoiding boulders to a distance of 25m or more on both sides of the road.

The transit problem is one of many to address when planning a Moon base. Every decision affects every other decision about how to proceed. Both horizontal and vertical positioning affects everything and both approaches have advantages and disadvantages along the way. It will be helpful to plan the entire base-building process in some detail before committing to any one option.

As proposed to NASA, the Starship HLS has hot-gas cosine thrusters mounted toward the bow be used instead of the Raptors when HLS is "within tens of meters" of the surface, specifically to avoid plume impingement by the Raptors. Elon made a later comment that these may not even be needed, but they are still in the design as proposed and accepted by NASA.

[KSHavre]

If water is available on the Moon, a water wall on a vertical Lunar Starship might be easier. If there isn't any water mining going on, I doubt we will have a large permanent base.

John

Even with water mining, what are you even doing with the water mining that will save you more money than the base costs to operate?

Beyond the questionable assumption that water mining is only desirable to offset base costs, let's not get off-topic.

Edit: I'm having trouble imagining a water wall "on" a vertical Starship, so I might need someone to elucidate how that might work.  But I have no trouble imagining how a polyethylene shield might lay over the top half, with the bottom half protected by regolith.  It's entirely possible that the top half might also be capable of taking the weight of 4 or 5 meters of lunar soil, but that might require a little bit of study (or googling).

I was envisioning a polyethylene wall or curtain designed to contain water around the inside walls. Once landed it is filled with Lunar sourced water.

John

I was with you John; much like a double hull ship that uses the gap between hulls for a storage tank. EDIT: {I am an ancestor of} Otto Sverdrup. He was the captain and then commander of a triple hull design Polar Expedition ship the Fram. I think they used the gap for storing fuel.

[Ionmars]

SS landing to base site

When deploying SS as a component of an initial moon base there will be engineering problems to solve along the way. One of these will be the transit of the SS from its landing site to the planned base location.

If we are just visiting the moon to show how it can be done, there is no need to transit anywhere; the landing site will be the base site for just one Starship. However, landing two or more ships to construct a base introduces more considerations. There will be a landing site and a base site separated by a safe distance because the plume of a Raptor during landing will discharge a significant amount of loose regolith and propel it at high speed in all directions. The safe distance between facilities will be determined by what measures are taken to protect personnel and equipment that are already landed. For example, equipment could be covered or buried in regolith before a second landing. Or a berm could be built around equipment to intercept debris flying horizontally. Or a berm could be built around the landing area for the same reason. Or equipment and the base itself could be located in a small crater so the sides of the crater could serve as a natural berm to intercept flying particles. Or the landing site could be located inside a small crate for the same reason. But before we jump on one of these solutions we should also consider relative elevations.

The SpaceX development site at Boca Chica may exemplify the elevation problem. When an SPMT carrying a Starship or propellant cylinder is moved from the production site onto State Highway 4 it is a smooth transition because SpX engineers had the foresight to build the surface of the production area to be the same elevation as the existing highway. The same is true at the intersection of Highway 4 with the launch area. Now consider how these smooth transitions could be accomplished on the Moon, between a landing site and a base site. This will involve building a smooth roadway between two areas with potential changes in elevation.

The design of the roadway between landing site and base will be affected by the choice of moving SS in vertical or horizontal position. Using SPMTs or equivalent to carry SS vertically will require a relatively smoother road surface with few or no abrupt bumps or dips and with modest slope. OTOH carrying SS horizontally will require clearing or avoiding boulders to a distance of 25m or more on both sides of the road.

The transit problem is one of many to address when planning a Moon base. Every decision affects every other decision about how to proceed. Both horizontal and vertical positioning affects everything and both approaches have advantages and disadvantages along the way. It will be helpful to plan the entire base-building process in some detail before committing to any one option.

As proposed to NASA, the Starship HLS has hot-gas cosine thrusters mounted toward the bow be used instead of the Raptors when HLS is "within tens of meters" of the surface, specifically to avoid plume impingement by the Raptors. Elon made a later comment that these may not even be needed, but they are still in the design as proposed and accepted by NASA.

Oh good point! 
I had forgotten about the change in landing technique, so maybe SS could land right beside the base and obviate the need for a road.

[Alberto-Girardi]

When asked about laying down Starship on its side on the Moon, Elon tweeted "no". Why do people keep going back to this harebrained idea?

https://twitter.com/elonmusk/status/1298452372704894979

I think this answer is very ambiguous, and leaves plenty of room for interpretation.  It's entirely possible that Musk was answering the question, "Would starship be able to lay down..." without giving a lot of detail.  There's no doubt in my mind that a pressurized Starship could be laid down as it is right now, although I think there's a good chance it would collapse if it lost pressure. That will need to be taken into account during modifications, but it's not a showstopper.

Regarding radiation protection, pack the Starship in question with polyethylene Whipple walls, and lay them over the top half after you tip it over.

I agree. It is possible that Musk understood that the original tweet meant that the SS would lay down itself withut other equipment. He could have answered that question that he found on his twitter homepage without thinking too much. Do you think that the future experience with catch arm might help with figuiring out if laying down a ship is possible?

[Oersted]

I wonder why old supertankers on Earth aren't repurposed as skyscrapers? Just stand them up on one end. I mean, it would be ten times easier than laying a spaceship on its side on another planet...

[DanClemmensen]

I wonder why old supertankers on Earth aren't repurposed as skyscrapers? Just stand them up on one end. I mean, it would be ten times easier than laying a spaceship on its side on another planet...

I know you are being faceteous, but there is a big difference. A Supertanker is not designed to support itself on its stern. A However, a Starship is designed to support itself against a lateral load of > 1 g, which it does during re-entry as it flies with the windward side facing the direction of motion.

[ThatOldJanxSpirit]

Three of my key principles are being violated here:

1) Keep it simple
2) Do as much work as you can on Earth where labour is orders of magnitude cheaper.
3) Proportionate consideration of risk.

Outfit your base on Earth in the gigantic fairing volume. If the stack is too wobbly to move, and/or the cargo lift is too much of a pain to use then get a big crane (you’ll probably want one anyway) and detach the nose section.

With regards to radiation exposure the expected unmitigated doses of around 0.5 Gy per year are high, but well within NASA career limits. Burying everything under 5m of regolith sounds good, but you’d need to do it all with remote controlled diggers to get an actual reduction in astronaut risk as EVA is a high risk activity. I’d expect to see localised shielding in high occupancy areas to control doses, rather than major civil engineering or spacecraft modifications as such measures are likely to be at best grossly disproportionate. 

[volker2020]

Three of my key principles are being violated here:

1) Keep it simple
2) Do as much work as you can on Earth where labour is orders of magnitude cheaper.
3) Proportionate consideration of risk.

Outfit your base on Earth in the gigantic fairing volume. If the stack is too wobbly to move, and/or the cargo lift is too much of a pain to use then get a big crane (you’ll probably want one anyway) and detach the nose section.

With regards to radiation exposure the expected unmitigated doses of around 0.5 Gy per year are high, but well within NASA career limits. Burying everything under 5m of regolith sounds good, but you’d need to do it all with remote controlled diggers to get an actual reduction in astronaut risk as EVA is a high risk activity. I’d expect to see localised shielding in high occupancy areas to control doses, rather than major civil engineering or spacecraft modifications as such measures are likely to be at best grossly disproportionate.

Keep it simple sounds good, than you have no access to that gigantic fairing volume on moon. If you want to move this station out, in one go, you need equally big doors. The method they want to use in orbit won't cut it on moon, because you need a way to stabilize the ship, when the center of gravity changes, or remove the complete nose, even when you have this very large crane (which by itself would be quite a complex piece of hardware).
2 winches sound rather straight forward compared to this.

ps. 80cm of regolith should do the trick, according to the paper referenced above.
pps. The horizontal station that is within the nose, could be finished on earth. (and would by definition be equally big). The part that might become harder, is using the tank area as additional storage. But in a direct comparison, that should be regarded an extra option.

[ThatOldJanxSpirit]

Three of my key principles are being violated here:

1) Keep it simple
2) Do as much work as you can on Earth where labour is orders of magnitude cheaper.
3) Proportionate consideration of risk.

Outfit your base on Earth in the gigantic fairing volume. If the stack is too wobbly to move, and/or the cargo lift is too much of a pain to use then get a big crane (you’ll probably want one anyway) and detach the nose section.

With regards to radiation exposure the expected unmitigated doses of around 0.5 Gy per year are high, but well within NASA career limits. Burying everything under 5m of regolith sounds good, but you’d need to do it all with remote controlled diggers to get an actual reduction in astronaut risk as EVA is a high risk activity. I’d expect to see localised shielding in high occupancy areas to control doses, rather than major civil engineering or spacecraft modifications as such measures are likely to be at best grossly disproportionate.

Keep it simple sounds good, than you have no access to that gigantic fairing volume on moon. If you want to move this station out, in one go, you need equally big doors. The method they want to use in orbit won't cut it on moon, because you need a way to stabilize the ship, when the center of gravity changes, or remove the complete nose, even when you have this very large crane (which by itself would be quite a complex piece of hardware).
2 winches sound rather straight forward compared to this.

ps. 80cm of regolith should do the trick, according to the paper referenced above.
pps. The horizontal station that is within the nose, could be finished on earth. (and would by definition be equally big). The part that might become harder, is using the tank area as additional storage. But in a direct comparison, that should be regarded an extra option.

No need to extract the habitat through doors; the fairing is the habitat.

There is nothing straightforward about conducting a controlled topple of a gigantic steel cylinder using winches and with workers in spacesuits. A crane is significantly simpler, and can be used for a range of other lifting operations.

[sebk]

Using a vertical Starship as a base has big advantages. You have your solar panels up so it's actually feasible to have them permanently lit (there are quite a few spots around the rim of Shackleton Crater which are within couple dozens of meters of permanently lit). As @livingjw said, use water to create shield. Just fill 50cm thick circumferential "pocket" with water and together with the walls, solar panels etc would form about 70g/cm^2 of shielding which is decent.

You don't even have to mine the water. Just land it in visiting ships. The shield would be 200t, so for example filling up the resupply ships to the to nominal 100t would solve the issue in a few resupply flights (I'm certain we won't be shipping exactly 100t of supplies on every flight, to the contrary I'd expect most supply flights to deliver less than half of that. So instead of letting the capacity unused, bring water).

Especially that the Starship-Base is useful even without filling the walls, just that radiation doses are higher and would limit stays to 2 years of a career. After the filling it could be extended multifold, as GCRs would be about halved compared to outside moon surface environment while solar particles would be filtered to negligible levels.

[Ionmars]

A lightbulb has turned on in my head. Employing Starship in horizontal position on another planet is a bad idea for a very good but non-engineering reason: It has become symbolic.

Most of us that follow SS development believe that SS will eventually be successful. It will land people on Mars; It will begin colonization of Mars: it will make possible our exploration of Europa, Titan, Eceladus, and further into the Solar  System and beyond.

In a nutshell:
Starship has become the symbol for Mankind’s entry into the Galaxy.

For this reason:
Starship, I salute thee. I shall never again suggest that you should lie supine on any planet.

[SkyRate]

For radiation protection, land or park the vertical ships in a ring, run a superconducting cable around that ring (at some to-be-determined optimum altitude) and power it. Now you have a torus-shaped magnetosphere. Essentially an inside-out van Allen belt.

[volker2020]

Three of my key principles are being violated here:

1) Keep it simple
2) Do as much work as you can on Earth where labour is orders of magnitude cheaper.
3) Proportionate consideration of risk.

Outfit your base on Earth in the gigantic fairing volume. If the stack is too wobbly to move, and/or the cargo lift is too much of a pain to use then get a big crane (you’ll probably want one anyway) and detach the nose section.

With regards to radiation exposure the expected unmitigated doses of around 0.5 Gy per year are high, but well within NASA career limits. Burying everything under 5m of regolith sounds good, but you’d need to do it all with remote controlled diggers to get an actual reduction in astronaut risk as EVA is a high risk activity. I’d expect to see localised shielding in high occupancy areas to control doses, rather than major civil engineering or spacecraft modifications as such measures are likely to be at best grossly disproportionate.

Keep it simple sounds good, than you have no access to that gigantic fairing volume on moon. If you want to move this station out, in one go, you need equally big doors. The method they want to use in orbit won't cut it on moon, because you need a way to stabilize the ship, when the center of gravity changes, or remove the complete nose, even when you have this very large crane (which by itself would be quite a complex piece of hardware).
2 winches sound rather straight forward compared to this.

ps. 80cm of regolith should do the trick, according to the paper referenced above.
pps. The horizontal station that is within the nose, could be finished on earth. (and would by definition be equally big). The part that might become harder, is using the tank area as additional storage. But in a direct comparison, that should be regarded an extra option.

No need to extract the habitat through doors; the fairing is the habitat.

There is nothing straightforward about conducting a controlled topple of a gigantic steel cylinder using winches and with workers in spacesuits. A crane is significantly simpler, and can be used for a range of other lifting operations.

I guess we agree to disagree. If the fairing is the habitat, you need a way to decouple those 2, which in my books would end up a rather complex problem.

To construct a crane capable of lifting ~20T with a height of at least 50m, would in itself be a major task. What do you think
how many separate modules would you need (you have to bring them down using the lift).

Using winches to topple a high object is old news even for the old Egyptians, and once you fixated the 2 or 3 winches and the hinge, there is not much human interaction needed.   

[Alberto-Girardi]

A lightbulb has turned on in my head. Employing Starship in horizontal position on another planet is a bad idea for a very good but non-engineering reason: It has become symbolic.

Most of us that follow SS development believe that SS will eventually be successful. It will land people on Mars; It will begin colonization of Mars: it will make possible our exploration of Europa, Titan, Eceladus, and further into the Solar  System and beyond.

In a nutshell:
Starship has become the symbol for Mankind’s entry into the Galaxy.

For this reason:
Starship, I salute thee. I shall never again suggest that you should lie supine on any planet.

Interesting phylosphical thought, but I could turn this around saying that is a symbol of the importance of sleep for humanity.

[Ionmars]

If Starship were to be employed only in vertical position, could an inter-ship hallway system still be employed?

I think yes. Crew Starships to be reused as habitats could be placed next to each other so that their doors face each other. An inter-ship connector ring would be placed over and around each door and welded to each ship, airtight. The outer edges of the ring would be curved to match the exterior of each ship (a chord of a circle with 4-1/2 m radius). A person would exit through the door of one ship, pass through the ring and enter through the door of the second SS. This would serve as a very short inter-ship hallway.

To connect multiple ships into a base-wide hallway system, a special variant  of cargo SS would sport four doors facing four directions, as suggested by the sketch below. There could be a series of 4-door units connected together in a line. The side doors would connect to habitat SS's or pressurized cargo units reused as greenhouses, laboratories, and repair shops.

In this particular example the habs and cargo sections of SS were not separated from their respective propellant tanks and propulsion units. So the hallway system and living quarters are elevated 20+ m above ground. In effect, Each SS hab would have its own basement consisting of empty  CH4 and O2 tanks, which could also be converted into living and working space over time.

The sketch shows the initial base cluster of SS's surrounded by a berm or wall built of regolith. This would have to be built up over time to eventually cover the base.

Like other alternatives this approach would have its advantages and disadvantages. A detailed analysis of alternatives will be needed to determine which could be constructed faster and at less expense.

More discussion of this type of approach may be found in the thread "Amazing Mars Habitats." See entries by TheRadicalModerate and others.

[Yggdrasill]

Having considered the different options, I think I would prefer constructing a fully functional lunar base on earth and simply landing it. With sufficient orbital refilling, in stages between LEO and LLO, a Starship could land several hundred tons of payload on the moon. That's enough to include sufficient radiation shielding internally in the fairing, and all the internal hardware of the base.

You would have to transfer some payload in space for this to work. A Starship lunar base could reach LEO with a maximum of around 200 tons of payload, and if you need 200 tons of water for the radiation shield, two reusable Starship launches would be required to launch the water into LEO, and then you would dock and pump the water over into the base.

There might be some added complication in trying to land a ~600 ton Starship lunar base on the moon, rather than the 300 (?) tons of an HLS landing, but this should be solvable with added thrusters. I'm guessing you would land it on a pre-scouted position that's almost perfectly flat, and maybe have radio-beacons to guide it in, which would reduce the complexity of the landing.

Edit: This also works quite well with @lonmars suggested construction method. With the four-port version, you could reduce the radiation shielding on the sides, while keeping the shielding on the top, and maybe shrink the propellant tanks for added habitation volume. With two variants of Starship you could construct a pretty massive and well-shielded base, if desired.

[Pitpen]

My 2 cents on the topic:

1) A lunar habitat module is not being built at the moment and using Artemis and Gateway as a measuring stick it translates into at least 5 years of lead time at best;

2) Starship should be already suitable for long term (months) space environment due to its intended purpose of sending people to Mars, so I think that 6 months lunar shifts would do the trick until a permanent solution will be developed and installed;

3) No need to put it horizontally thus removing the ability to escape Moon in case of emergency, but just use it as it is. NASA has already trusted its high habitat concept and deemed it safe enough to assign 3B$ to transport humans onto it;

   

[Yggdrasill]

The sketch shows the initial base cluster of SS's surrounded by a berm or wall built of regolith. This would have to be built up over time to eventually cover the base.

Just thought of a method for adding regolith between the vertical Starships, or covering any lunar base design really, without needing the regolith to be compacted to allow a bulldozer to drive on top of it. It also allows for steeper slopes than a bulldozer-based solution.

You could actually use something similar to a snow cannon to eject regolith skyward and raining it down on the structure. The relatively low density of regolith, and the low gravity on the moon means it shouldn't rain down with too much force, while also allowing for good throwing distances and height. It's also aided by the lack of an atmosphere. The actual device might be nothing more than a controllable high speed conveyor belt, with probably also some mechanical separators on the input-side, to filter out rocks that are too big/heavy and might damage the structure.

Using such a mechanism for regolith deposition makes it very easy to gather the regolith. You would just need to push regolith into the rotating blades of the input. Or you could have an input suitable for a dumptruck.

[edzieba]

In this concept, the Starship is being used as little more than a cylindrical hollow within a regolith berm. All other work of burying and fitout is the same as if you'd created that hollow in any other manner. If you have an alternate method to create that hollow that can be carried within a Starship, you obviate the need to expend one in the first place.
Barring ISRU methods (not impossible, but simply not demonstrated so low TRL), the two most obvious alternatives are an pressure-supported inflatable bladder (pros: light, compact, you need to pressurise the structure anyway. cons: fail-unsafe in event of pressure loss) or a deployable structure e.g. concrete canvas (pros: fail-safe in event of pressure loss so can be used for airlocks and vehicle garages, durable, a viable structure for operational use even before burying. Cons: greater upmass than pure inflatable membrane, requires some quantity of water to be carried if ISRU not an option).

[Alberto-Girardi]

The sketch shows the initial base cluster of SS's surrounded by a berm or wall built of regolith. This would have to be built up over time to eventually cover the base.

Just thought of a method for adding regolith between the vertical Starships, or covering any lunar base design really, without needing the regolith to be compacted to allow a bulldozer to drive on top of it. It also allows for steeper slopes than a bulldozer-based solution.

You could actually use something similar to a snow cannon to eject regolith skyward and raining it down on the structure. The relatively low density of regolith, and the low gravity on the moon means it shouldn't rain down with too much force, while also allowing for good throwing distances and height. It's also aided by the lack of an atmosphere. The actual device might be nothing more than a controllable high speed conveyor belt, with probably also some mechanical separators on the input-side, to filter out rocks that are too big/heavy and might damage the structure.

Using such a mechanism for regolith deposition makes it very easy to gather the regolith. You would just need to push regolith into the rotating blades of the input. Or you could have an input suitable for a dumptruck.

The idea is interesting, but I think that separating large rocks to a perfect accuracy and mantaining a simple system might be difficult, expecially because only one too large rock thrown could yeld a lot of damage.

[Yggdrasill]

The idea is interesting, but I think that separating large rocks to a perfect accuracy and mantaining a simple system might be difficult, expecially because only one too large rock thrown could yeld a lot of damage.

I'm pretty sure that's a solved challenge in various industrial plants making gravel, concrete, etc. I believe they use things like grates with different hole-sizes where finer material drops through the grate and coarser material bounces off to the side.

But alternatively you could crush the regolith into the required fineness. That way you also don't need to discard any of the collected regolith. The crushing can for instance be done with a set of rollers, where the opening between the rollers is 1 cm. That way no material higher than 1 cm can pass through without getting crushed.

[Slarty1080]

If Starship were to be employed only in vertical position, could an inter-ship hallway system still be employed?

I think yes. Crew Starships to be reused as habitats could be placed next to each other so that their doors face each other. An inter-ship connector ring would be placed over and around each door and welded to each ship, airtight. The outer edges of the ring would be curved to match the exterior of each ship (a chord of a circle with 4-1/2 m radius). A person would exit through the door of one ship, pass through the ring and enter through the door of the second SS. This would serve as a very short inter-ship hallway.

To connect multiple ships into a base-wide hallway system, a special variant  of cargo SS would sport four doors facing four directions, as suggested by the sketch below. There could be a series of 4-door units connected together in a line. The side doors would connect to habitat SS's or pressurized cargo units reused as greenhouses, laboratories, and repair shops.

In this particular example the habs and cargo sections of SS were not separated from their respective propellant tanks and propulsion units. So the hallway system and living quarters are elevated 20+ m above ground. In effect, Each SS hab would have its own basement consisting of empty  CH4 and O2 tanks, which could also be converted into living and working space over time.

The sketch shows the initial base cluster of SS's surrounded by a berm or wall built of regolith. This would have to be built up over time to eventually cover the base.

Like other alternatives this approach would have its advantages and disadvantages. A detailed analysis of alternatives will be needed to determine which could be constructed faster and at less expense.

More discussion of this type of approach may be found in the thread "Amazing Mars Habitats." See entries by TheRadicalModerate and others.

An interesting idea but Starship is 50m high so the amount of regolith required would be huge. Another problem would be how are the Starships going to be neatly arranged like that? I would have thought that they would need to land some distance away from each other to avoid blast damage and transporting a 50m Starship across the Moon would not be an easy task.

[Vultur]

My 2 cents on the topic:

1) A lunar habitat module is not being built at the moment and using Artemis and Gateway as a measuring stick it translates into at least 5 years of lead time at best;

2) Starship should be already suitable for long term (months) space environment due to its intended purpose of sending people to Mars, so I think that 6 months lunar shifts would do the trick until a permanent solution will be developed and installed;

3) No need to put it horizontally thus removing the ability to escape Moon in case of emergency, but just use it as it is. NASA has already trusted its high habitat concept and deemed it safe enough to assign 3B$ to transport humans onto it;

 

Yes.

Also, what's the goal/purpose?

If medium term missions are desired (say several months to a year, similar to stay times on ISS) with a small number of crew, the Lunar Starship can presumably be a sufficient habitat without being tipped over, and with no special modifications (maybe carrying more life support consumables than a regular Artemis mission, but nowhere near what you'd need for 100 people on a Mars Starship).

For really permanent settlement (same people staying for a lifetime) you might need more shielding, and for a larger scale base or settlement Starships might be inefficient - but are there any current plans/stated goals for anything on that scale for the Moon, comparable to Elon Musk/SpaceX's Mars plans?

[Oersted]

I wonder why old supertankers on Earth aren't repurposed as skyscrapers? Just stand them up on one end. I mean, it would be ten times easier than laying a spaceship on its side on another planet...

I know you are being faceteous, but there is a big difference. A Supertanker is not designed to support itself on its stern. A However, a Starship is designed to support itself against a lateral load of > 1 g, which it does during re-entry as it flies with the windward side facing the direction of motion.

Yes, it can deal with an even lateral load, but how are you going to achieve that on a rocky lunar surface, and
just as important, while placing it horizontally?

[DanClemmensen]

I wonder why old supertankers on Earth aren't repurposed as skyscrapers? Just stand them up on one end. I mean, it would be ten times easier than laying a spaceship on its side on another planet...

I know you are being faceteous, but there is a big difference. A Supertanker is not designed to support itself on its stern. A However, a Starship is designed to support itself against a lateral load of > 1 g, which it does during re-entry as it flies with the windward side facing the direction of motion.

Yes, it can deal with an even lateral load, but how are you going to achieve that on a rocky lunar surface, and
just as important, while placing it horizontally?

First, the lunar gravity imposes only a .16 G load,  which is  lot less than the load during re-entry, and I'm not sure how "even" the forces are during re-entry: I understand it's a bit of a rough ride. Next, I would use a rake to clear the rocks, just as you would when laying a patio on sand. I might even add a conformal squishy layer to the outside of the HLS. The existing TPS would probably work just fine, but a specifically designed layer would work better.  There may be very good reasons to not tilt the ship, but protection from the surface is not one of them.

[Lampyridae]

Land in a 50m+ deep crater. Fill the unused space in the cone with regolith and use the area immediately beneath for sleeping. That deck is basically completely shielded save for albedo neutrons.

[sanman]

I wonder why old supertankers on Earth aren't repurposed as skyscrapers? Just stand them up on one end. I mean, it would be ten times easier than laying a spaceship on its side on another planet...

I know you are being faceteous, but there is a big difference. A Supertanker is not designed to support itself on its stern. A However, a Starship is designed to support itself against a lateral load of > 1 g, which it does during re-entry as it flies with the windward side facing the direction of motion.

Yes, it can deal with an even lateral load, but how are you going to achieve that on a rocky lunar surface, and
just as important, while placing it horizontally?

First, the lunar gravity imposes only a .16 G load,  which is  lot less than the load during re-entry, and I'm not sure how "even" the forces are during re-entry: I understand it's a bit of a rough ride. Next, I would use a rake to clear the rocks, just as you would when laying a patio on sand. I might even add a conformal squishy layer to the outside of the HLS. The existing TPS would probably work just fine, but a specifically designed layer would work better.  There may be very good reasons to not tilt the ship, but protection from the surface is not one of them.

Furthermore, you could pile regolith/dust/sand underneath the sides of an horizontally lying Starship, in order to provide support and stability. That could be done as part of covering it with regolith for protection against micrometeorites & radiation.

Since Lunar Starship HLS would already have signifcant habitable volume, this could be used as a shirtsleeve environment to then convert the tank volume into considerably greater living space. With relatively non-toxic volatiles like LOX & CH4, there shouldn't be any major toxic residues that couldn't be purged to space.

With Lunar Starship HLS being overkill for its role as a lander, this could give it extra margins for structural reinforcement modifications to make it a more durable base on the ground.
Just as vertical Starships could be stacked close to one another, horizontal Starships could similarly be linked to create a larger contiguous volume.

[daveklingler]

While lots of studies have been done in this vein over the past 60-or-so years (the ASCE Aerospace Division's body of work is gigantic by itself), we need to remember that the reason for this particular study is that there is only one pressure vessel designed for use in space in mass production.

The point of this student exercise is that anyone who wants to build a huge lunar base could probably buy ten Starships for an order of magnitude less than just the cost overruns on a bespoke hab from any other company. Ten Starships, ten months.  For anyone else, working 40-hour work weeks, certainly five years, and likely ten, for something that isn't self-launching.

So while most of the civil engineering work has been studied to death, Starship will soon become the $1 hammer in a toolbox containing almost nothing else.  Complain all you want that a beautiful spacecraft is going to waste, or that it's not optimal, but at the end of the day there are no other comparable choices.  "When all you have is a hammer..."

[daveklingler]

In this concept, the Starship is being used as little more than a cylindrical hollow within a regolith berm. All other work of burying and fitout is the same as if you'd created that hollow in any other manner. If you have an alternate method to create that hollow that can be carried within a Starship, you obviate the need to expend one in the first place.
Barring ISRU methods (not impossible, but simply not demonstrated so low TRL), the two most obvious alternatives are an pressure-supported inflatable bladder (pros: light, compact, you need to pressurise the structure anyway. cons: fail-unsafe in event of pressure loss) or a deployable structure e.g. concrete canvas (pros: fail-safe in event of pressure loss so can be used for airlocks and vehicle garages, durable, a viable structure for operational use even before burying. Cons: greater upmass than pure inflatable membrane, requires some quantity of water to be carried if ISRU not an option).

Don't forget that there is no location on the Moon that's not fairly close to a smorgasbord of lava tubes in a variety of sizes up to several hundred meters in diameter.  Once you have an established hab, you go shopping for a lava tube, because it's already up there.  There's an ASCE paper from about 30 years back by Cassandra Coombs mapping all of the most desirable candidates.

Lessee here...whups, looks like she wrote several.

https://ui.adsabs.harvard.edu/abs/1992lbsa.conf..219C/abstract