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.