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Tom Kalbfus

Banned

Registered: 2006-08-16

Posts: 4,401

Building a globe around the Moon

What if we build this around the Moon using lunar materials?
Except we make this globe a solid surface quarter scale model of the Earth, excavating the material of the Moon to make it s smooth sphere so this globe can rotate around it with ease, establish an axial tilt that points to the star Polaris, then would build a larger sphere around it to hold in atmosphere. The result would look something like this:

SpaceNut

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From: New Hampshire

Registered: 2004-07-22

Posts: 29,001

Re: Building a globe around the Moon

The circumference of the Earth is 40,070 kilometers, speed is 1670 kilometers/hour ( 1037 miles/hr). This decreases by the cosine of your latitude so that at a latitude of 45 degrees, cos(45) = .707 and the speed is .707 x 1670 = 1180 kilometers/hr. The Moon's Circumference 10,921 kilometers, rotation nearly matches its orbital period of 28 days. https://en.wikipedia.org/wiki/Orbit_of_the_Moon one complete revolution every 8.85 Earth years, or 3,232.6054 days, as it rotates slowly in the same direction.

https://en.wikipedia.org/wiki/Moon

Surface area   3.793×107 km2  (0.074 Earths)
Volume          2.1958×1010 km3  (0.020 Earths)
Mass            7.3477×1022 kg  (0.012300 Earths)

Assuming the globe dome is glass; plenty thick and is suspended to the new world.

So what would the shell thinkness be for such a world?

What would be the Atmospheric height to the outer globe dome?

Are we looking at a liquid water surace?

Tom Kalbfus

Banned

Registered: 2006-08-16

Posts: 4,401

Re: Building a globe around the Moon

The circumference of the Earth is 40,070 kilometers, speed is 1670 kilometers/hour ( 1037 miles/hr). This decreases by the cosine of your latitude so that at a latitude of 45 degrees, cos(45) = .707 and the speed is .707 x 1670 = 1180 kilometers/hr. The Moon's Circumference 10,921 kilometers, rotation nearly matches its orbital period of 28 days. https://en.wikipedia.org/wiki/Orbit_of_the_Moon one complete revolution every 8.85 Earth years, or 3,232.6054 days, as it rotates slowly in the same direction.

https://en.wikipedia.org/wiki/Moon

Surface area   3.793×107 km2  (0.074 Earths)
Volume          2.1958×1010 km3  (0.020 Earths)
Mass            7.3477×1022 kg  (0.012300 Earths)

Assuming the globe dome is glass; plenty thick and is suspended to the new world.

So what would the shell thinkness be for such a world?

What would be the Atmospheric height to the outer globe dome?

Are we looking at a liquid water surface?

There are two spheres, one that rotates over the actual surface of the Moon about once every 24 hours at an axial tilt identical to the Earth's, and the outer sphere which holds in the atmosphere. Since the troposphere ends approximately at the height of Mount Everest, which is 5 miles in altitude, then on the Moon, the breathable layer of atmosphere would extend upwards to 30 miles in altitude, we might also want to have 6:1 vertical exaggeration on the topography. I figure the ground sphere would rest in magnetic currents like a maglev train on a maglev track, that means the Moon has to be smoothed out to become a near perfect sphere, all the mountains and craters would have to be leveled or filled in, a superconducting surface would be laid on top, and the independently rotating sphere would be held suspended on magnetic fields. The roof sphere which holds onto the atmosphere simply rests on top of the atmosphere and rotates with the bottom sphere. I suppose there would have to be landing platforms on top of the roof sphere, and airlocks to allow passage inside.

The main advantage of the Moon is its position in the Solar System, it orbits in the same orbit as the Earth, and it receives the same amount of light, it is the largest object in Earth's orbit besides the Earth.

We can build these instead, but it seems to me that it would be much easier to build a double shell around the Moon and rely on the Moons gravity that to build these Bishop Rings that are 2000 km in diameter, which relies on carbon nanotubes to hold itself against centrifugal force. the materials of the shell around the Moon would not need to be quite so exotic, as they have to counter the inward force of gravity, rather than an outward centrifugal force. We would probably need to import water and other volatiles, the shell could be made out of aluminum.

Last edited by Tom Kalbfus (2015-10-15 06:18:58)

SpaceNut

Administrator

From: New Hampshire

Registered: 2004-07-22

Posts: 29,001

Re: Building a globe around the Moon

The atmosphere thickness can be even less as we can presurize it to what ever level that we want but its the inner sphere that must take the added mass of those living on it and the mass of the air.

I like the idea of a varying topicgraphic land scape.

The power source to keep the sphere spinning and suspended above the moons surface should be seperate from the one that the colonist use for daily usuages and also seperate from the life support unit.

Not really in favor of the second concept as a lunar location but it might prove to be a better one or deep space..

Tom Kalbfus

Banned

Registered: 2006-08-16

Posts: 4,401

Re: Building a globe around the Moon

The atmosphere thickness can be even less as we can presurize it to what ever level that we want but its the inner sphere that must take the added mass of those living on it and the mass of the air.

I like the idea of a varying topicgraphic land scape.

The power source to keep the sphere spinning and suspended above the moons surface should be seperate from the one that the colonist use for daily usuages and also seperate from the life support unit.

Not really in favor of the second concept as a lunar location but it might prove to be a better one or deep space..

The power source can be a giant solar array located at L4 or L5, it will stay in a fixed position relative to the Moon, the energy can then be beamed to a collector dish suspended above a walled off hole in the sphere centered around the North Pole or the South Pole. Life support would be plants and animals of the ecosystem.