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Building in sections is also a huge advantage in that you don't have to pay to envelope the entire moon at one time; you can pay as you go.

Your suggested internal air pressure is far in excess of the air pressure actually used in existing structures (well over 100 times as great). This actually is a huge problem too. Even a 1 km square structure would require impossible strength to keep the roof (or the sides of the dome) from destruction as it would have a net lift of over 10 million tonnes.

Standard PVC does not have near the operating temperature range that you would need for lunar use. -- it becomes soft and distorts, and may even melt at the top daily lunar temperature (2 week long days and nights)

Even without temperature problems, PVC would not last last due to oxygen degradation from the inside of the dome, esp. at high temperatures that accelerate the oxygen reactions, and photo degradation from the abundant ultraviolet light during the day.

Other materials would be more durable, but are going to be more expensive and likely require more research. For example, glass has many desirable characteristics including transparency at visible wavelengths. Some modern flexible glass display materials might serve or could be adapted. On a large scale, air pressure could certainly be support such a structure, were it not for the high pressure that would destroy it.

1. How to build -- no need to bother, since it will break apart once you inflate it

2. How to maintain, you must build it in sections, or invent new tech to repair your roof in situ, but for safety you must build it in sections. Actually, even when built in sections, you will still want the automated repair bots to handle most of the maintenance without closing the sections.

3. Any sort of airlock design would be acceptable for access to the pressured region. Presumable a mix of large and small airlocks of various designs would ultimately be desirable. [1]: https://en.wikipedia.org/wiki/Air-supported_structure

8000 meters worth of atmosphere means you already have a significant fraction of the atmospheric mass needed for the whole moon. On earth, about 65% percent of the atmosphere is in the lowest 8000 meters. Due to the lower lunar gravity, the pressure drop with altitude will be slower than on earth, but if you add enough air, you eventually get a nice breathable atmosphere.

Sure, it leaks into space, but the rate will slow enough to be usable perhaps. Some people have calculated that you would only need to top off such a lunar atmosphere only once per 10,000 years or so. You could add a solar wind shield to the moon to slow the rate of air loss too.

Terraform the moon by drop plenty of comets, etc. selectively to get the lunar spin back to a decent day duration that provide as well as the oxygen, nitrogen, etc. If you have high enough tech, you get all the replacement oxygen you needed from a couple of icy comets. You also want inert gas to add to the overall mass of the atmosphere. There is probably no better choice for this than nitrogen and there is plenty of ammonia in some planets, moons, and comets to fill this need.

There are a few big complications, once you add atmosphere, the oxygen will start reacting with the existing lunar surface -- think lots of rust being formed, so you many need to wait a few thousands years after initial terraforming for things to settle down.

Building in sections is also a huge advantage in that you don't have to pay to envelop the entire moon at one time; you can pay as you go while you expand. The 8000 meter high is a pretty strong constraint on the smallest individual dome size (as the vertical extent is 8000m, as you would probably want the horizontal dimension to be at least 8000m, so you are probably 100 sq. km. or so for the individual domes -- thus you need about 380,600 domes to cover the moon.

Your suggested internal air pressure is far in excess of the air pressure actually used in existing inflated structures (well over 100 times as great). This actually is a huge problem too; even a 1 km square structure would require impossible strength to keep the roof (or the sides of the dome) from destruction as it would have a net lift of over 10 million tonnes.

Standard PVC does not have near the operating temperature range that you would need for lunar use. -- it becomes soft and distorts, and may even melt at the top daily lunar temperature (2 week long days and nights).

Even without temperature softening problems, PVC would not last long due to oxygen degradation from the inside of the dome, esp. at high temperatures that accelerate the oxygen reactions, and photo degradation from the abundant ultraviolet light during the day. Micro-meteors and ablation from solar wind won't help the dome much either.

Other materials would be more durable, but are going to be more expensive and likely require more research. For example, glass has many desirable characteristics including transparency at visible wavelengths. Some modern flexible glass display materials might serve or could be adapted. On a large scale, air pressure could certainly be able lift such a structure, were it not for the high pressure that would destroy it.

1. How to build -- no need to bother, since it will break apart once you try to inflate it

2. How to maintain -- you must build it in sections, or invent new tech to repair your roof in situ, but for safety you must build it in sections. Actually, even when built in sections, you will still want the automated repair bots to handle most of the maintenance without closing the sections.

3. Any sort of airlock design would be acceptable for access to the pressured region. Presumable a mix of large and small airlocks of various designs would ultimately be desirable. [1]: https://en.wikipedia.org/wiki/Air-supported_structure

8000 meters worth of atmosphere means you already have a significant fraction of the atmospheric mass needed for the whole moon. On earth, about 65% percent of the atmosphere is in the lowest 8000 meters. Due to the lower lunar gravity, the pressure drop with altitude will be slower than on earth, but if you add enough air, you eventually get a nice breathable atmosphere with earth normal pressure at ground level.

Sure, it leaks into space, but the rate will slow enough to be usable perhaps. Some people have calculated that you would only need to top off such a lunar atmosphere only once per 10,000 years or so. You could add a solar wind shield to the moon to slow the rate of air loss too, though there is disagreement on how much difference it actually makes.

Terraform the moon by dropping plenty of comets, etc. selectively to get the lunar spin back to a decent day duration that provides the oxygen, nitrogen, etc. If you have high enough tech, you get all the oxygen you needed from a icy comets, moons, etc. You also want inert gas to add to the overall mass of the atmosphere. There is probably no better choice for this than nitrogen and there is plenty of ammonia on some planets, moons, and comets to fill this need.

There are a few big complications, once you add atmosphere, the oxygen will start reacting with the existing lunar surface -- think lots of rust being formed, so you many need to wait a few thousand years after initial terraforming for things to settle down. That's not too bad, since you have to wait a long time for the moon to cool from the cometary bombardment anyway.

To be specific re: your questions.

If you have high enough tech, you get all the replacement oxygen you needed from a couple of icy comets. You also want inert gas to add to the overall mass of the atmosphere. There is probably no better choice for this than nitrogen and there is plenty of ammonia in some planets, moons, and comets to fill this need.

There are a few big complications, once you add atmosphere, the oxygen will start reacting with the existing lunar surface -- think lost of rust being formed, so you many need to wait a few thousands years after initial terraforming for things to settle down.

But, wouldn't it be great to look up in the sky and see another blue marble.

Just thought of another big problem -- the huge windstorms inside the dome. Due to the month long days and corresponding temperature changes, there will be very active internal storms systems.

To be specific re: your questions.

Terraform the moon by drop plenty of comets, etc. selectively to get the lunar spin back to a decent day duration that provide as well as the oxygen, nitrogen, etc. If you have high enough tech, you get all the replacement oxygen you needed from a couple of icy comets. You also want inert gas to add to the overall mass of the atmosphere. There is probably no better choice for this than nitrogen and there is plenty of ammonia in some planets, moons, and comets to fill this need.

There are a few big complications, once you add atmosphere, the oxygen will start reacting with the existing lunar surface -- think lots of rust being formed, so you many need to wait a few thousands years after initial terraforming for things to settle down.

But, wouldn't it be grand to look up in the sky and see another blue marble.

1. How to build -- no need to bother, since it will break apart once you inflate it

2. How to maintain, you must build it in sections, at invent new tech to repair your roof in situ, but for safety you must build it in sections

3. Any sort of airlock design would be acceptable for access to the pressured region. Presumable a mix of large and small airlocks of various designs would ultimately be desirable. [1]: https://en.wikipedia.org/wiki/Air-supported_structure

1. How to build -- no need to bother, since it will break apart once you inflate it

2. How to maintain, you must build it in sections, or invent new tech to repair your roof in situ, but for safety you must build it in sections. Actually, even when built in sections, you will still want the automated repair bots to handle most of the maintenance without closing the sections.

3. Any sort of airlock design would be acceptable for access to the pressured region. Presumable a mix of large and small airlocks of various designs would ultimately be desirable. [1]: https://en.wikipedia.org/wiki/Air-supported_structure

How about a better idea. It would be better just be forget the dome entirely, and just add an atmosphere to the moon.

8000 meters worth of atmosphere means you already have a significant fraction of the atmospheric mass needed for the whole moon. On earth, about 65% percent of the atmosphere is in the lowest 8000 meters. Due to the lower lunar gravity, the pressure drop with altitude will be slower than on earth, but if you add enough air, you eventually get a nice breathable atmosphere.

Sure, it leaks into space, but the rate will slow enough to be usable perhaps. Some people have calculated that you would only need to top off such a lunar atmosphere only once per 10,000 years or so. You could add a solar wind shield to the moon to slow the rate of air loss too.

If you have high enough tech, you get all the replacement oxygen you needed from a couple of icy comets. You also want inert gas to add to the overall mass of the atmosphere. There is probably no better choice for this than nitrogen and there is plenty of ammonia in some planets, moons, and comets to fill this need.

There are a few big complications, once you add atmosphere, the oxygen will start reacting with the existing lunar surface -- think lost of rust being formed, so you many need to wait a few thousands years after initial terraforming for things to settle down.

But, wouldn't it be great to look up in the sky and see another blue marble.