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#51 2024-05-02 15:19:21

Calliban
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From: Northern England, UK
Registered: 2019-08-18
Posts: 3,777

Re: Para Terra formation in Orbit, with orbital services.

Void, that is interesting.  I hadn't seen that graphic before, but it does suggest that there is plenty of space around Ceres to orbit things.  A Ceres synchronous orbit is 722km above its surface.  That would be a good place for an orbital ring, with space elevators descending to the surface.  Ceres gravity is so weak that elevators could be made from steel.

I think the idea of Ceres being tunnelled out like Swiss cheese is feasible eventually, as it is the single largest water body in the inner solar system, Earth included.  That water will have value.  An orbital ring attached to space elevators, allows that water to be transfered to low thrust spacecraft docked at the ring without wasting propellant.  I think ultimately, the ring will have a number of rotating habitats tethered to it.  Workers in the Ceres mines would probably live in these habitats and ride the elevator down to the surface each day.  The ring also allows propellant free transport between any two habitats.

Last edited by Calliban (2024-05-02 15:25:29)


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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#52 2024-05-02 18:51:16

Void
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Registered: 2011-12-29
Posts: 7,778

Re: Para Terra formation in Orbit, with orbital services.

You have stimulated my thinking, you and Isaac Arthurs video.  What I was working with may be less attainable and/or stable than I would like.  It was an attempt to conserve volatiles.  But if the human race eventually develops fusion of isotopes of Hydrogen and perhaps Helium, or if they learn how to beam power extremely long distances, then, and endless flow of volatiles can come inward from the Kuiper belt and even the Oort Cloud.

So, conservation of volatiles does not have to be quite so stringent.  This then allows the entertainment of what you have suggested, and perhaps also some embellishments of it.

A practical path is to make something that can be in harmony with its surroundings, and also which is not too vulnerable to terrorists, and idiot savants who may see a path to a parasitic damage of what is built to benefit themselves.

Unfortunately, we will likely always have some people who refuse to walk on their two hind paws.

So, you suggest a "Nulled Ring" where gravitation of Ceres and the centrifugal spin will balance to keep stability.

Looking at Isaac Arthurs work, I notice that Ceres has a 4-degree tilt of axis, and it thought to be variable in that aspect between 2 to 20 degrees tilt.

We might consider building a mini version of what he suggested without artificial gravity induced on the ring, but rather artificial gravity on spin gravity devices attached to the ring.  If the ring is properly built than spinners with axis parallel to the axis of Ceres could spin for artificial gravity but mirrors also on the ring could convey light into them if that was desired.  In a similar manner, solar power devices could swivel on such an axis as well, but only one spin per rotation of Ceres, synchronous, so that much of the time they gather solar energy.

But we have another game we can play.  If we move mass from Ceres out to the ring, then the spin should be reduced.  But then you need to expand the circumference of the ring to compensate, but the gravity of Ceres is reduced, and the spin rate of Ceres may be reduced.

Here are some images of Banks Orbit, but what is being discussed here has similarity but are not Banks Orbitals: https://www.bing.com/images/search?q=Ba … C3&first=1

So, one could go as far as they like, even eventually consuming all of Ceres to build a very big one.  So, then the gravitational field would be dispersed.  But perhaps only a partial conversion would make sense.

If we say that Ceres or another asteroid has a north and south rotational pole, then the ring would have a north and south edge/mooring point.  Then the Satellite axis of the individual devices would have bearings one on the north edge of the ring and one on the south edge of the ring.  This could be true for synthetic gravity machines, and for solar power devices, whatever type you like of those.

And the ring being like a ladder with rungs connecting the north and south rims, could allow sunshine to these devices much of the time.  In the case of the solar devices, they may pivot once for each orbit of Ceres, and in the case of the space habitats, mirrors might convey light into them much of the time, and maybe it can be a bit like variations in sunlight during a partly cloudy day.  So, you might fake a day/night balance.

Does that seem to be reasonable?

Done

Last edited by Void (2024-05-02 19:13:36)


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#53 2024-05-03 09:19:30

Void
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Posts: 7,778

Re: Para Terra formation in Orbit, with orbital services.

Well, I feel that that segway stimulated by Calliban helped in the formation of a "Ladder" geostationary hoop.  Such would be two rigid rails, a north and a south, that would be joined by rigid ladder rungs.  And swiveling devices could be connected by some sort of bearing to the two rails, in places between the rigid ladder rungs.  This would be a form of "Nesting" of small elements into a larger superstructure.

Some Finish people have suggested a Megga Satellite around Ceres which would also foster "Nesting": https://www.sciencealert.com/could-huma … anet-ceres
Image Quote: satellite-1.jpg
Quote:

(P. Janhunen, arXiv, 2020)

But these are not "Hill Sphere Shells".  I wonder if other asteroids could support such shells.

https://en.wikipedia.org/wiki/List_of_e … _asteroids
Quote:

List of exceptional asteroids

Scrolling down:
The "S", "M", and "X" asteroids may well lack an abundance of volatile substances, but the others may have much.
But even volcanic Vesta is thought to be covered with Carbonaceous dust on much of its surface.

Some questions emerge.

A hill sphere shell may be easier with a smaller asteroid.  And also, the notion of perhaps a "Beyond Hill Sphere" shell.

You could even have a shell that has no world inside of it at all.

If such shells were thought of as a digestive system, they might ingest small asteroids and process them.

Unless I am in a mistake(s), then I think that a shell equal or larger than a hill sphere, will not suffer from gravity induced warping and collapse, if the world object contained can be kept centered.

My intention for these shells would not be that they would hold a high air pressure, but rather thin gasses subject to molecular flow.
https://en.wikipedia.org/wiki/Free_molecular_flow
Quote:

Free molecular flow

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From Wikipedia, the free encyclopedia
Free molecular flow describes the fluid dynamics of gas where the mean free path of the molecules is larger than the size of the chamber or of the object under test. For tubes/objects of the size of several cm, this means pressures well below 10−3 mbar. This is also called the regime of high vacuum, or even ultra-high vacuum. This is opposed to viscous flow encountered at higher pressures.[1] The presence of free molecular flow can be calculated, at least in estimation, with the Knudsen number (Kn). If Kn > 10, the system is in free molecular flow,[2] also known as Knudsen flow.[3]

So, a bit like an exosphere, but perhaps a thick one.

In this condition a hole in the shell will let some gas escape, but not from collective molecular motion but just because that hole was in the path the molecule was traveling in a straight line.

There is a question as to if the pressures from solar emissions will push the shell outward.  Photons, and the Solar Wind.  I don't know the answers yet.  I suspect that there is an aligning force from the major planets that may tend to keep objects in place, if their gravity dimple is large enough, relative to the other forces exerted on the object, such as from the sun.  So, there may be value in anchoring on a large enough of the tiny worlds, if that is true.

The purposes of such a shell are to contain things, to provide a solar exposed surface for solar power devices, and a sphere where nested objects can be associated into.

And I am not sure of all of this.  A shell on its own may not have a large enough gravity dimple to be "Noticed" by the larger objects of the solar system, so it may be free to obey the solar wind and the photon pressure on it.  So, an advantage may exist for holding a significant mass inside of it, so that perhaps the shell and the mass it encloses, may stay in an appointed orbit.

But as I have said I am not sure.  This is where perhaps we learn more.

If a shell is solar locked, with one side facing the sun and the other facing the outwards from the sun, then considerable cold may exist on the outward portions of the shell.  This may be used to condense molecules of gas that are in Molecular flow inside of the shell.  Adsorption could be used.

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

OK, perhaps sorption then: https://en.wikipedia.org/wiki/Sorption
Quote:

Sorption is a physical and chemical process by which one substance becomes attached to another. Specific cases of sorption are treated in the following article

So, then an object in the shell could be heated as desired to gas off, but not at a rate faster than your sorption methods can handle.

And this leaves the problem, how do you keep the treated object centered in the shell?  Magnetics might work.  Maybe some complex mechanical method,   The object may likely spin and we do not want to spin this shell.

Possibly air pressure might help, if you could shoot jets of compressed air from the inside of the shell, or inversely have a second interior shell that encases the object and spins with it, and then that shell emits jets of gas into the region between shells. 

I would like to see if magnetics could do it.

In process, I guess.

Done

Keep in mind that one of the values of the shell is the amount of sunlight it can intercept.

Done

Last edited by Void (2024-05-03 10:24:51)


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#54 2024-05-04 07:11:43

Void
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Registered: 2011-12-29
Posts: 7,778

Re: Para Terra formation in Orbit, with orbital services.

So, it begins to seem to me that the ? (Not quite density) of an object determines the ratio of solar forces vs gravitational force.

As far as the solar wind is concerned the Earth is less dense with a magnetic field than without one.

As far as to total amount of force photons exert on the Earth, the Earth's magnetic field does not exist.

Smaller objects seem to have fewer stable orbits than larger ones.  Dust might be swept out of the solar system if it is of the correct size.

I you converted Ceres into a giant shell completely, it would have the same total gravitation but that would be distributed differently.  But the force of Photons and Solar wind would be greater.  So, to some degree gravitation allows objects to communicate with each other to maintain orbital patterns developed early in the solar system, but at some point if you change the ratio of gravitation of an object to forces that are exerted on an object, then it is possible that an object might deviate from its orbit.

That is why a solar sail might work.  It does not have sufficient gravity to be locked into place.

But maybe I don't have it right just yet.  Tell me so it you think that.

Anyway, for a Dyson Sphere, if you made it of hollow spheres, that would be interesting, but would the solar wind spin them up to higher orbits, or could they be locked into stable orbits, by gravitation?

The way I look at it now photons may not be that much trouble as they would more equally give additive and subtractive thrust to a hollow sphere.  But the solar wind spirals out, it might give a force to push hollow spheres with insufficient gravity, to higher orbits.

As I have said maybe I don't have the correct model in my head, but this is what I am thinking.

But a sphere with a significant mass, might be kept locked into place by the influences of the larger objects of the solar system.

A sphere allows interception of a lot of photons from the sun.  It would also have a hollow space within with a modified space environment.
And you could have travel paths over the interior or exterior surface of the sphere, and also you could have line paths within the sphere, such as cables or trusses which could connect one point on the interior of the sphere with another.

Any thoughts?

Done

If we get borged with spheres, perhaps a cube?

Done

Last edited by Void (2024-05-04 07:23:35)


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#55 2024-05-06 07:19:26

Void
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Registered: 2011-12-29
Posts: 7,778

Re: Para Terra formation in Orbit, with orbital services.

Well, I have a little time to goof around.  I have been thinking of both gravity and "Flatoids".  Gravity as expected has not been solved.  But I can play with flatoids instead.

A coin or washer might be what I would call a Flatoid.  Having 3 dimensions, but with one dimension much shorter than the other two.  The shape of a healthy red blood cell, might be considered as "Flatoidish". smile  The shape would facilitate the reception of light transmitted from a light source such as the sun, and the reverse side to be facing the universe can be an emitter of low energy photons.

So, I have thought that converting a small world(s) to a Flatoid might be interesting.

I have been thinking how converting a planet to a Dyson Sphere might redistribute mass in such a way that the other planets might notice as far as orbits, and inertia.  It could be a problem.  Maybe upset the balance previously established.  World in collision would not be good, or to be flung away, or dump into the sun.

But converting tiny worlds into Flatoids might be more acceptable.

The mass of an asteroid would still be centered to the center or a flatoid.  The nature of the gravitational field would alter, but should be the same intensity.

A Flatoid would have an inside and an outside just like a sphere or a cube, but would more effectively intercept light from a light source, such as the sun.

A flatoid may present less disturbance to the flow of the solar wind than would a sphere or cube.  (That is subject to surface area as well though).

Photons mostly hitting strait on to a flat surface might not increase or decrease the orbit of the Flatoid, but of course you could "Sail" it just a bit on photon flow.  (This would take enormous amounts of time to have any significant effect).

The Trojan L4 and L5 locations may be interesting, particularly for Jupiter.  Many small worlds in there.  While the light intensity is maybe ~3% of Earth's, is there a reason to care?  If is an energy source.  Concentrating mirrors could be used.

Around and inside of a Flatoid you could have "Organs" for various purposes.  Such as Spin Gravity Habitats, and Seas, and such things.  Also, microgravity farms as well, or perhaps very low gravity worlds.

In a Sun/Planet "L4 or L5" location, these might become so big as to have notable gravitational force.  That along with the envelope provided by the Lagrange zone, "L4 & L5" may tend to keep loose stuff from drifting away to become collision hazards.

Something fun to think about.

For a world like Venus or Mars, a ballistic capture method might allow capture of an asteroid to an orbit of one of those planets, and then perhaps it does not take that much energy to move some of the materials to a "L4 or "L5" location.

This is for fun of course, to think about.

Done

Last edited by Void (2024-05-06 07:44:24)


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#56 2024-05-06 07:47:46

Void
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Registered: 2011-12-29
Posts: 7,778

Re: Para Terra formation in Orbit, with orbital services.

As per my last post, let us not forget our bygone membership: https://newmars.com/forums/viewtopic.php?id=7092

Not the same exactly, at all, but a shell which does not enclose a world.  In the family, perhaps a "Shirt Sleeve" relative.

Not Flatoid though.

Done

Last edited by Void (2024-05-06 07:49:28)


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#57 2024-05-07 09:38:40

Void
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Registered: 2011-12-29
Posts: 7,778

Re: Para Terra formation in Orbit, with orbital services.

It is just a alternate notion of what may be of value.

The Jupiter Trojans and Greeks, are significant and have a gravitational pocket they exist in.  So, more mass and less energy.  The Mars L4 and L5 have less mass and more energy.

Layering may be the method.

Done


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#58 2024-05-08 10:20:53

Void
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Registered: 2011-12-29
Posts: 7,778

Re: Para Terra formation in Orbit, with orbital services.

So quiet on the site!

Anyway, here is a sort of drawing that suggests making a FlatBox, or maybe the word Flatoid is allowed, where you provide a nested method where layering is also used to cope with harsh environments such as the space environments.

cXYjJgV.png

While photovoltaics or heat engines might be used, I am hopeful that Anti-Solar cells may have merit to generate electricity from heat radiating away to the universe from inside of the nested structures.

Of course, synthetic gravity devices could be included into this nested system.

I don't know what the limits would be as far as the spread of the flat structure.

Possible ways to generate electricity from the emission of photons are considered:
https://en.wikipedia.org/wiki/Thermopho … conversion

https://thehill.com/changing-america/su … %20a%20day.

https://scitechdaily.com/anti-solar-cel … -at-night/

Well, maybe it will become possible to capture sunlight and then use the deep cold of the universe to generate electricity.

Various methods may come to mind of how to do that.  But as I have said heat engines and photovoltaic cells may also be options.

Done

I will add this low spin gravity garden notion (Cut-Away) drawing.  Such might be put inside of the FlatBox Structures: 02zMiIL.png

Because of a low spin rate, you may not need a vacuum to allow the rotor to spin and generate synthetic gravity of some small fraction of a g force.

Done

Last edited by Void (2024-05-08 10:50:33)


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#59 2024-05-08 19:42:19

Void
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Posts: 7,778

Re: Para Terra formation in Orbit, with orbital services.

(th) posted: https://newmars.com/forums/viewtopic.ph … 67#p222867

Quote:

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 17,349
Email
For Void re post showing interesting drawings ...

https://newmars.com/forums/viewtopic.ph … 64#p222864

The bottom drawing in this long post caught my eye ....

The concept deserves support ....


(th)

The above quote is incomplete, as I was getting Internal Server Error.

Your ideas are interesting (th). 

I purposely left an incomplete architecture so that others could consider how they might improve it.  So, welcome.

Keep in mind that these structures would most likely be at 2 AU or even the orbit of Jupiter, 5.2 or so AU.  Sunlight at these locations would range from ~.25 that of Earth to ~.03 that of Earth.  The Trojan and Greek Asteroids will be at ~.03 that of Earth.

Shifting technologies suggest that various solutions to potential overheating are possible.

For instance, if you had a window that absorbed UV and Infrared, then that window could get hot, and you could use it to push a heat engine.  A radiator on the reverse side of the FlatBox, could have radiator fins and radiate heat off into the universe.

Or, you could have solar cells in the window that absorbed wavelengths that plants don't use.

If you had air filled conduits that people could pass though that would connect various pressurized nested habitats, those could serve as radiators.

Another likely bend in reality that is likely to occur is robots.  If they reduce the price of a $1.00 device to $.01, then economic thinking will change radically.

For instance, with low cost of hardware to produce power, and low cost of produced LEDS, you might not bother with windows at all but have LED lighted gardens.  Heat buildup would not be so bad with those.

Previously that was considered too expensive for the produce you might get, but if hardware prices deflate by 100, then the calculation is likely changed.  Same for solar power device hardware.  If you want more you just make more, it should be almost dirt cheap.

Your comments are desired.

Done

Last edited by Void (2024-05-08 19:59:22)


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#60 2024-05-09 08:38:29

Void
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Registered: 2011-12-29
Posts: 7,778

Re: Para Terra formation in Orbit, with orbital services.

I just previously said that FlatBox structures might be suitable between approximately 2 AU and 5.2 AU (Jupiter and Trojans and Greeks).  But really there are other places.  It more or less requires a distribution of needed materials for our kind of organic and inorganic processes.

So, I consider that Deimos and Phobos may apply as what they do not have Mars may have.

A Box is not necessarily Square like or Rectangle like.  Some boxes can have a circular shape.  A washer shape may do.  A washer has a thickness to it that we could assign the dimension of depth to if we want to.  And then length and height are defined by the inner edge and outer edge of the washer shape.  The washer shape could hold a moon such as Deimos or Phobos inside of its inner open space, which is a hole.

To some extent then this would resemble the mining method proposed by Calliban, a sort of hoop.

Methods to anchor the structure to such a moon could involve pinching insertions, and/or a lasso.

We sometimes speak of space elevators, so a cable that can lasso a moon may not be that silly.

As for insertions, I guess if you had one at each pole of spin on the axis of the object that may also be helpful.  You could put bearings on each pole, allowing the Washer Type FlatBox, to pivot against the moons inertia to face the sun all the time, only being occulted by this moon and Mars on occasion.

Deimos being smaller may be easier to master in this way.

Done for now.

Last edited by Void (2024-05-09 08:43:38)


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#61 2024-05-09 10:19:32

Void
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Registered: 2011-12-29
Posts: 7,778

Re: Para Terra formation in Orbit, with orbital services.

The purposes of the "Skin" of a FlatBox, can be considered.
-To keep lose parts from drifting away.
-To modify the internal temperatures.
-To control internal lighting and block UV.

Last edited by Void (2024-05-09 10:21:12)


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#62 2024-05-09 10:25:07

Void
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Registered: 2011-12-29
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Re: Para Terra formation in Orbit, with orbital services.

I am getting Internal Service Error, and am not able to complete the previous post.

To continue the previous post........
-To protect from impactors.

An old trick to use for impactors is to have a double wall.  The outer wall penetrated, but then the impactor possibly vaporized of turned into dust.  Then being less a threat for the inner wall.  Possibly the skin is magnetic, so that robots can drive on it, to patch holes that occur.

I guess that is progress in the description of options.

Done

Yet another function of the skin would be to assist in recapture of gas molecules that escape into the enclosure.  Typically, a very thin gas level, unless there is a major leak.  Some sort of sorption aided by cold may work to capture escaped gas molecules.

It will be necessary to have blowout sections in the skin in the case that something explosively decompresses inside of the FlatBox.

Done

Last edited by Void (2024-05-09 10:44:43)


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#63 2024-05-09 19:58:25

Void
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Registered: 2011-12-29
Posts: 7,778

Re: Para Terra formation in Orbit, with orbital services.

There have been opinions all along, about a "Best" power system.  Everyone has their opinion.

As an example, Mars is considered by some to be a poor location for solar.  Some case can be made for that, particularly due to unpredictable dust storms, and also the seasons are almost twice as long as Earth's, and the amount of sunlight to a surface area is less than half of Earth.  Mars may or may not have sufficient fission fuels.  It does have a lot of concentration of fusion fuel.

But this topic is about "Para Terra formation in Orbit, with orbital services.".  And that is a different situation.  There should be no dust storms in orbit, and most of the time the sun is available unless you go behind a shading object such as a planet.

So, in orbit even of Mars, sunlight duration of a time period is almost 100% in many cases unless you are in a very low orbit.  And we do not expect dust storms in orbit or precipitation to block light.

Last edited by Void (2024-05-09 20:09:17)


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#64 2024-05-09 20:17:06

Void
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Posts: 7,778

Re: Para Terra formation in Orbit, with orbital services.

ISE is bothering me again, I cannot complete a post.

Continuing then.............

We can use mirrors on Earth or in orbit of Earth.  Similarly, out to the orbit of Saturn (Just a guess), mirrors will also work.  The sunlight is spread out, so the mirrors have to become larger.

And in the case where robotics may drop the cost of hardware by a factor of 100 eventually, the cost of such a mirror system may not be a showstopper.

I am very in favor of the development of various types of nuclear as well though.

Just like on Earth, it may be best if several types of power sourcing can be implemented and perfected.

Done

Last edited by Void (2024-05-09 20:21:10)


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#65 2024-05-10 09:41:54

Void
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Posts: 7,778

Re: Para Terra formation in Orbit, with orbital services.

Here is some material that it seems was poorly placed, in my opinion.  It has no future where it is, so I will transplant it to here:
https://newmars.com/forums/viewtopic.ph … 91#p222891
Quote:

This may suggest possibility(s): zjcWSKG.png

https://newmars.com/forums/viewtopic.ph … 94#p222894
https://newmars.com/forums/viewtopic.ph … 96#p222896
Quote:

Here are some axial tilts included: https://en.wikipedia.org/wiki/Axial_tilt

I think that this may matter for the simplicity of Heliostats:
Quote:

Mercury    0.03
Jupiter    3.13
Moon    6.68
Earth    23.44
Mars    25.19

Some of these can be variable over time though.  I don't think moons are very variable, but I am not positive about it.

Ceres is currently 4 degrees but can vary over 2-20 degrees.

So, for smaller worlds, such a method might be looked the asteroid belt may provide materials for Fission but it also reasonably can have solar energy.

Although Phobos and Deimos may well not be asteroids, they certainly be adopted into the asteroid "Kind".

Where free floating solar power methods could be done in various places in the solar system, it may be convenient to associate them with the mass of a small world.

Here again is a list of exceptional asteroids: https://en.wikipedia.org/wiki/List_of_e … _asteroids

This asteroid does not have a favorable axis tilt for the above materials of this post, but might be preferable to Ceres, if it has a bit of Nitrogen in its materials.   If space elevators might work for Ceres, I would expect that they would work on this world.

This little world will have such a low gravity that I expect that robotically manipulated mirror systems would work just fine, but would have more degrees of freedom built in than the more static version I suggested earlier in this post.

Such a little world could host multiple space elevators, and those could lead to orbital mirrors where energy may be collected and transferred to target locations by microwaves.

And then there are the Trojans and Greeks of Jupiter and Mars: https://en.wikipedia.org/wiki/Trojan_(celestial_body)
Image Quote: InnerSolarSystem-en.png

Isaac Arthur may have suggested structures that could be built inside of each of the two pockets.
https://isaacarthur.net/video/statites- … -quasites/
Quote:

Statites, Lagites, and Quasites
Jan 7, 2024

The lighting inside of the Jupiter Trojans and Greeks will be similar to that of Jupiter.  So, you probably has to do quite a bit of concentration to bring the collected light to useful intensity of focus.

Here is another video that is significant to the materials: https://www.bing.com/videos/riverview/r … &FORM=VIRE
Quote:

34:07

Lagrange Point Space Settlement
YouTube
Isaac Arthur
118.7K views
3 months ago

My interest at this time is the L4 & L5 Sun/planet pockets for Jupiter and Mars.  But after looking at Isaac Arthur's videos, L3 and maybe L2 and L1 interest me.

The Jupiter L4 and L5 have a very large number of asteroids in them, and it is likely that those have a suitable distribution of materials.
If you for some reason decided to build a singular structure in each of those gravitational pockets, they would be able to intercept a very large amount of sunlight, even though sunlight is spread out quite a lot.

While the Trojans and Greeks would be materials to build stuff from in those pockets, the Hilda's might also be accessed.

https://en.wikipedia.org/wiki/Hilda_ast … 53%20Hilda.

Anyway, using FlatBox structure, with nested substructures, then you have a mass that you may install propulsion devices on.  Isaac Arthur has mentioned some of them.

I have indicated that I am interested in other planetary "L" locations.  But there are few captured objects in them naturally.  Mars has a few stony objects.  https://en.wikipedia.org/wiki/Mars_troj … understood.

And they are rather small.

But from the "Super Stations" which might be created in Jupiter L4, L5, and L3 locations, you may have mass driver propulsion and also power beam propulsion.  I don't suggest power beaming that crosses the solar system, but rather a collection of lasers or other energy device that could allow a delta-V change by vaporizing matter to propel a load towards a more inward location.

A combination of Mass Driver and then power beam might work.  But it would not be for humans but for cargo.  The cargo's could be robotic solar sails that unfold after launch and then navigate to a Mars or ever more inward "L" location.

These might be composed in part of organic materials, so that they could deliver useful materials to the locations sent to.  They would not be the most effective and thin solar sails, as their purpose would be to deliver themselves as a material resource, and we may not care if it takes years for them to arrive at their destination.

But once you have built up the Martian L3, L4, and L5 locations then you might start transferring materials to the L3, L4, and L5 locations for the Sun/Earth.  And then maybe even those for Venus, and I don't know but maybe for Mercury?

But you see the potential, rather than building a Dyson Sphere, do this and really get enough of what you want.

And other asteroids could be involved in this process as well.

Done

Last edited by Void (2024-05-10 11:39:50)


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#66 2024-05-10 13:13:37

Void
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Registered: 2011-12-29
Posts: 7,778

Re: Para Terra formation in Orbit, with orbital services.

In the use of the Jupiter Trojans and Greeks, while it might be nice to send loads inward to the inner solar system it may also be sensible to send loads out to places like the Saturn system.

If mass drivers were to be used for this, then they may be very long ones.

One option to deal with delivery of loads to Saturn, Uranus, and Neptune might be to simply impact an icy moon with metals or whatever you were sending.

But I generally think that to go beyond Saturn, nuclear of some kind will be preferred, if not actually needed.

But I do wonder for the Jupiter Trojans and Greeks just how large a single "FlatBox", structure could be.

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#67 2024-05-10 19:21:34

Void
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Registered: 2011-12-29
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Re: Para Terra formation in Orbit, with orbital services.

One thing that has been in my mind at the edge of my attention is impactors and a FlatBox.

A thing that I think is important in this is to collect the results of an impact, and to less-so shed more materials into space.

Here first is at least on article where more professional people have considered the matter: https://ntrs.nasa.gov/citations/20080004653
I suppose that this is nicely worded, quote:

In the event of exposure to a hypervelocity impactor, the sacrificial impactor disrupting/shocking layer is perforated while shocking the impactor breaking it into fragments, and/or melting it, and/or vaporizing it, thus providing a dispersion in the form of an expanding debris cloud/plume which spreads the impact energy of the impactor over a volume formed by the primary spacing element between the sacrificial impactor disrupting/shocking layer and the spacecraft surface. This significantly reduces impact lethality at the spacecraft surface.

But the nature of the FlatBox, the thickness, materials, and the nature of the impactor will greatly influence the results of an impact event.
Speeds of impact would be less in a "L" location as differential speeds expected are less,

As for LEO, of course these can be very dangerous impacts.  Never-The-Less, I am tempted to consider how an Aluminum balloon might perform to collect certain types of space junk.  If it were large, then the penetration from the outside would travel fairly far, spreading as it went, and perhaps the other side could hold the results in its interior.  This of course would be influenced by the nature of the impactor, and the nature of the capture Shell/FlatBox.

I will attempt to draw something:  P1XDj09.png

A very simple first try, lots of baffles inside.  This would need a means of electric power and some kind of propulsion.  And it would likely need to be refilled periodically with materials.

Robots that travel in pairs may repair holes.  They may be on each side of a sheet of metal and to attract each other.

As for the shell itself we want something that will react to an impact by allowing the impactor in and yet shattering it or vaporizing it or melting it or all of the above.

The interior of this would not be pressurized.

Other methods are in process of being developed and they will have their places, mostly by getting rid of big chunks.  In this case we may hope to sweep orbits of smaller very annoying pieces.

As I have said LEO is much more a problem than is a "L" location.  Isaac Arthur said so. smile

Last edited by Void (2024-05-10 19:47:40)


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#68 2024-05-11 10:18:59

Void
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Re: Para Terra formation in Orbit, with orbital services.

Continuing a bit more, I found this: https://www.timeanddate.com/astronomy/s … n%20indeed.  Quote:

3.7%
Sailing deeper into space, we encounter the mighty gas giant Jupiter at 5.2 AU, so we are able to calculate that Jupiter experiences around 3.7% of the light that reaches Earth, a weak Sun indeed.

I think that the "L3", "L4", and "L5" locations for Sun/Jupiter will be that amount +/- some factor as things wandering in the "L" locations will be at times closer or further from the sun.

https://en.wikipedia.org/wiki/Jupiter_trojan
Image Quote: InnerSolarSystem-en.png

For "L4" and "L5", if you made a triangle that had a corner on the sun and a corner on the most forward and backward Trojan, or Greek, then you would sort of describe a "Cone of Light".

The intensity of the light has not so much attenuated as it might from passing though dust or clouds, but it has spread out.  It is nearly all still there, minus a small amount that solid objects or gas molecules may have blocked.

But if using mirrors to Un spread it, the mirrors can only have a certain amount of efficiency.

A perfect mirror or close to perfect mirror would be very expensive I suspect: https://en.wikipedia.org/wiki/Perfect_mirror

And in space erosion from micro-impactors would erode the surface of a mirror reducing its efficiency.  Having no data, I will suppose that mirrors used in the "L" zones might be 80% efficient.  Just a number I took as a guess.

So, 3.7 * .80 = 2.96, I will round that up to 3.00, as my number of efficiencies was just a guess anyway.

But unlike for planets or moons, the light is just about 24/7 all year long, I expect, so really the delivered light usable is about 6.00 that you might get on the surface of the Moon, on average, which has no atmosphere.

So, if we divide 100/6 = 16.66666666666667 mirror size, to bring the value back up to Moon average sunlight received.  I will round that up to 17, just cause I spose I can, this is my post after all.

So, if you were to build mirrors into a FlatBox structure, then you would have a considerable volume within, that you could nest substructure into.

A question I have is could you build a singular FlatBox, that occupied all of the cone of light of the Trojans or Greeks?  That would involve expending it down below and above the plane of Jupiter's orbit.  Probably their are limits to force tolerance for that, but even though at about 5.2 AU, that is the interception of a whole lot of light.  And of course we think that the Trojan and Greeks may each have a significant distribution of materials with which to make such huge FlatBoxes.

This would then represent a vast power supply, in the inner "Ice Belts" of the solar system.  That could be valuable.  Not a Dyson sphere, but really something that may not be subject to the danger of a mass run-away of collisions.  (Kessler Syndrome sort of).

But perhaps having the GDP capable of mounting missions out of the solar system.

As for power beaming.............

For spacecraft: https://en.wikipedia.org/wiki/Laser_propulsion
Keep in mind that synthetic gravity nested habitats could be used for power storage so that a burst of needed energy could be procured.

But could you beam power from the inner solar system to the FlatBox assemblies that may be in the "L4", "L5" and maybe even "L3" locations?

I think that due to the potential of large surface area you could.  It would not matter so much if the light were to spread out, and so also aiming might not be that critical.

In fact, you might want very poor focus, not more than the sun gives.

The downside is that overlapping laser projections could generate hot and less hot spots.  But if your flatBox mirror system were made as not Gracile, but Robust, it may be able to handle it.

So, if it were economic, then indeed inner solar system locations might project light out to "L4", "L5" and "L3" locations.  In return desired materials might be sent inward to the solar system but means of Mass Drivers, and Beam propulsion and then Solar Sails, perhaps.  Perhaps some other methods will emerge as well.

That is enough.

Done

Last edited by Void (2024-05-11 10:59:08)


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#69 2024-05-11 16:35:59

Void
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Re: Para Terra formation in Orbit, with orbital services.

So, I wonder if microwaves would be a way to transmit power from the inner solar system to "L" locations.

I wish I understood microwaves better.  But such projections might allow the pushing of materials wanted in the inner solar system from the outer solar system.

Mars/Sun "L" locations would not be as big as the Jupiter ones, but still would be significant.  But to build them up most materials would have to be transported to them.

Done

Last edited by Void (2024-05-11 16:37:48)


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#70 2024-05-12 09:34:27

Void
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Re: Para Terra formation in Orbit, with orbital services.

This is a rather nice video about "L" points from Scott Manley, and is about 2 years old: https://www.youtube.com/watch?v=7PHvDj4TDfM
Quote:

What Makes Lagrange Points Special Locations In Space

Scott Manley
1.67M subscribers

Subscribe

For the Jupiter "L4" and "L5", it appears to me that it might not be that hard to push materials from the asteroid belt into them.  With patience Solar propulsion may be usable, particularly sailing the solar wind.  It may also be possible that materials from the moons of Jupiter might be moved there.

Large platforms put in the "L4" and "L5" might send loads out both the inner solar system and the outer solar system.

For power at these "L" points I have focused on solar, but in reality, nuclear of many sorts might also be used as it may develop.  Even "Orion" type propulsion might be used.

But from an electrical source(s), also Linear Mass Driver, Spin Launch, Power Beam propulsion, and Tether release methods might be used.  While the "L4" and "L5" locations tend to hold objects in their pockets, balancing the materials launched to outer and inner solar locations may make that work better.

So, from Mars to the Asteroid belt and then the Jupiter "L4" and "L5" may open the whole solar system. That would be even better if fusion power becomes practical.

Done

This is a question I have had: "Transferring space craft between Varangian points?"
Here is a general response: https://www.bing.com/search?q=Transferi … cc=0&ghpl=

A specific: https://www.spaceacademy.net.au/library … grangp.htm
Image Quote: lpoints.gif

Transferring materials among "L" points: https://space.stackexchange.com/questio … e-utilized  Image Quote: rZJWL.png
Quote:

Yes and yes. You are asking about weak stability boundary trajectories. These offer a significantly reduced delta V trajectory from the Earth to the Moon compared to a direct transfer. Two downsides compared to direct transfer are much longer transit times and rather narrow launch windows.

Done

There is some question about how many Jupiter Trojans there really are.  They may have overestimated the number by far.  But this is typical of certain forces which seek to hobble the human race to serve their selfish desires.  But it might be somewhat true.  The manic-depressive contests are how they divide and conquer.

But just a few good Trojans may matter a lot: https://en.wikipedia.org/wiki/Jupiter_trojan

One Example: https://en.wikipedia.org/wiki/624_Hektor
So, if we allow that 50% of the asteroids mass is suitable to make solid structure a crude estimate could be made of how big of a FlatBox you could make out of it.

Diameter: 225 km, but I will use a cubic 200 km.  200 * 200 * 200 = 8,000,000 cubic km.
50% can go into structure by my arbitrary guess, so 4,000,000 cubic km. 
I will suppose that 1 cubic km can host 100 cubic km of hollow space within, if the solid materials are turned into a shell.

So, then 400,000,000 hollow cubes of 1 km on a side. 

If put into a "FlatBox" arrangement, then a FlatBox square of 20,000 by 20,000 with a 1 km depth.

So then how big is Texas?

https://en.wikipedia.org/wiki/Texas
Quote:

695,622 square kilometers
The size of Texas is approximately 268,581 square miles (695,622 square kilometers)12345.

Slap me up if you see a blatant error.  I was just trying to get a "feel" about relative size.

Done

Last edited by Void (2024-05-12 11:07:26)


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#71 2024-05-13 04:50:02

Calliban
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From: Northern England, UK
Registered: 2019-08-18
Posts: 3,777

Re: Para Terra formation in Orbit, with orbital services.

The Jupiter Trojans appear to be volatile rich bodies.  This makes them more attractive targets for human settlement than stony asteroids.  Solar energy will still be cheap at that distance from the sun, because concentrating mirrors can be extremely thin in low gravity conditions.  Even the largest Trojan has surface gravity no greater than 0.01g.

I think the Trojans could be valuable resources to support Mars terraforming in the longer term.  Their orbital speed is 13.1km/s.  Using mass drivers, it would be possible to launch packages of icy material onto elliptical orbits that cross the orbit of Mars.  The packages would explode as the hit the Martian atmosphere.  Regular deliveries would saturate the upper atmosphere with water vapour.  This would create a warming effect, as water vapour is a greenhouse gas.  Ultraviolet radiation from the sun would break down the water vapour into hydrogen and oxygen, with the former escaping into space.  The oxygen would accumulate within the atmosphere.

Something similar could be done for Venus and the Jovian moons.  Callisto could be bombarded with material launched from the Trojans, creating a water vapour atmosphere.  Photolysis would slowly break this down into hydrogen and oxygen, with the former escaping.  In the case of Venus, we want to include a lot of non-ice components that will create a sun shielding dust in the upper atmosphere.  This will allow the surface to cool and much of the crushing CO2 atmosphere will eventually liquefy on the surface.

All of these project require that humanity achieves a scale of development that dwarfs the present industrial capacity of Earth.  But free space in the inner solar system provides anabundance of uninterupted solar energy.  The Tronans and outer asteroid belt contain all of the materials needed for industrial civilisation.  And the space available for development out there is enormously greater than the surface habitable volume of Earth.  So unbounded industrial development is possible.  A few centuries from now the industrial capabilities of a much greater human civilusation will be orders of magnitude greater than what we have today.

Last edited by Calliban (2024-05-13 05:02:13)


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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#72 2024-05-13 14:09:02

Void
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Re: Para Terra formation in Orbit, with orbital services.

Yes, that is an encouraging set of notions.  The opportunities appear to exist.  Thanks.

Done

Last edited by Void (2024-05-13 14:09:23)


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#73 2024-05-15 17:45:16

Void
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Re: Para Terra formation in Orbit, with orbital services.

I have been considering some ideas: smile
https://www.bing.com/images/search?q=ri … RE&first=1
Not those of course, but perhaps to have as much legacy.

I have previously asked the question, "Why not use the Orion Drive to send payloads around the solar system?".
But of course it is ta a large extent because they are nukes.  I think that someday, collaboration between major powers may allow it.

And then I have wondered if you could use chemical detonations in a similar manner.

For instance, aluminum foil containers, with an explosive paste in them.  Alice is Aluminum powder in water ice.  A paste apparently can be made of Aluminum Powder and LOX.  What if you put a series of those behind a payload and sequentially ignited them with a laser?  (Or set off a nuke to ignite them?).

What I am after is alternatives to things like Mass Drivers or the mass use of valuable volatiles.  (Alice is an exception).

I have been considering a slotted launch tube for rockets.  I am of course considering that this might be in association with large platforms in locations such as the Trojans-Greeks, and the Asteroid belt, as I have recently been posting about that.

Such a tube as I first considered it would be like a tube where you cut a slot down the length of it.  Whereas a rocket is ignited inside of it the plume would be vented through the slot to prevent excessive overpressure.  The idea is to keep the nose of the rocket in a greater partial vacuum than the tail engine would be in.  Something like this might also be possible with a very long hot staging segment such as is on the newer starship between the 1st and 2nd stages.

I have considered a laser that can fire into the segment to further heat the rocket plume.  It would need to be able to follow the rocket as it raced through the plume.

I have considered an inverse Alice, where the tube is coated with a solid propellant substance.  Possibly just a thermal reactive expansion occurring or maybe even a chemical reaction of some kind.

While Mass Drivers are impressive, they are very complex electric devices.  I have hoped for something perhaps a bit simpler.

You perhaps could use a Methane Oxygen device, or CO Oxygen.

Or if you could coat the tube with perchlorate, then the rocket might run a plume with excessive fuel that would react to it.  Of course you would then need to recoat the tube each time.

Probably a lot of things to go to recycling here as per ideas, but you never know maybe someone will get a more practical idea from it.

Enough for now, I guess.

Done

Last edited by Void (2024-05-15 18:07:14)


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#74 2024-05-16 13:16:44

Void
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Re: Para Terra formation in Orbit, with orbital services.

When in doubt, I guess it may not hurt to consult a better authority: https://www.youtube.com/watch?v=HlmKejRSVd8
Quote:

Dyson Spheres

Isaac Arthur
783K subscribers

803K views  6 years ago
A Dyson Sphere, or Dyson Swarm, is a collection of megastructures enclosing a star to gather all of it energy. We will look at myths and misconceptions about Dyson Spheres, as well as a number of additional purposes they can be put to, from allowing interstellar travel to generating black holes …

No big surprise that if you can think of something then someone else may have done it before you.

Ladder worlds is an example.  Umm.........I guess a "Rung World".

https://www.reddit.com/r/IsaacArthur/co … ung_world/
Image Quote: rung-world-v0-1B7ojAPqxPdqgYorNfsbrMCktstgoEHGOdBN86ElQjI.jpg?width=640&crop=smart&auto=webp&s=fea7512451c0ae125baad1a94eda80d4f4706bb1

Quote:

I would suggest building the ring around Earth-Luna Lagrange point 5. That would be fully adjustable. You could keep adding rungs.

But I have had a concern about where to get the organic chemicals to do that, except from difficult sources.

I would think about the L4 and L5 of Sun/Jupiter, and also Mercury, and Mars of course.  Each has their strengths.  But I think you need a full catalog of available materials, and you need energy.  The convenience of low gravity also may matter.

1) L4 and L5 of Sun/Jupiter: Well, you have low gravity, but it is far off.  Actually, since you would not be orbiting a particular world, you might make the ladder a spiral, and just keep growing outward like a snail shell.  You could incorporate a FlatBox structure into it.  There should be Nitrogen available in the Tholen's of the Trojans and Greeks, or from one of Jupiter's moons.

2) Mercury.  Not sure if Nitrogen may be locally available in large amounts.  If it was covered in oceans a long time ago, maybe in the deep rocks.  Definitely has no shortage of energy.  Maybe Nitrogen from Venus.

3) Mars has some Nitrogen, but not a huge amount.  It lacks good solar energy so that a "Rung World" might work well for it.  Sources of materials could be Phobos and Deimos, Mars itself, asteroids.  In the case of some asteroids it may be possible to Ballistic Capture some materials into Martian orbit from those that are terrestrial crossing asteroids.

4) Ceres or another large asteroid might host one of these as well, as they are sort of on the way to the L4 & L5 of Sun/Jupiter, and it is thought that Ammonia is available.

5) Callisto?  Well, maybe.  But maybe would rely on nuclear more than the others.

6) Titan?  Well, similar to #5 but solar may not be impossible with mirrors.  Lots of Nitrogen to spare.

Done

Last edited by Void (2024-05-16 13:36:18)


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#75 2024-05-16 20:20:56

Void
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Re: Para Terra formation in Orbit, with orbital services.

So, maybe for Mars, in the long run?

Ladder worlds is an example.  Umm.........I guess a "Rung World".

https://www.reddit.com/r/IsaacArthur/co … ung_world/
Image Quote: rung-world-v0-1B7ojAPqxPdqgYorNfsbrMCktstgoEHGOdBN86ElQjI.jpg?width=640&crop=smart&auto=webp&s=fea7512451c0ae125baad1a94eda80d4f4706bb1

Supposedly, the CO2 in the Martian ice caps could double the surface pressure of the atmosphere.  So, that would indicate that where the pressure is now 5.5 mbar, it could be 11.0 mbar.  The pressure calculator indicates that that would be a boiling point of 8.5 degrees C.

https://www.mathscinotes.com/2012/10/ea … llibars%29
Quote:

The Wikipedia gives two points of reference for the atmospheric pressure on Mars:

Peak of Olympus Mons: 30 pascals (0.3 millibars)
Hellas Planitia: 1,155 pascals (11.5 millibars)

But when 5.5 might shift to 11.0 mbar, 0.3 mb on Olympus Mons will not double, and 11.5 mbar in Hellas Planitia will more than double, as the increased atmosphere will compress. 

So, highest pressure will be more than 23 mbar.  So, a boiling point of >19.8 in the best case.

If you had a rung world plus energy assets in orbit you might send both microwaves and reflected sunlight to places where water might pool.  And you could send them to places where ice could be melted to flow to where it might pool.  The water would mostly be ice covered, but under those conditions occasional small amounts of open water might occur.  Streams can run where they are mostly covered in ice, and lakes can exist where they are mostly covered in ice.

Microwaves could be useful as they may penetrate the ice even if a bit dusty.  Then sunlight reflected to the ice would possibly cause accumulated dust to sink though the ice over time.

But also microwave receivers could create useful power, and then the waste heat from processes could be dumped into the lakes.

So, pretty much tucking waste heat into water to help thaw the planet, and provide a living biome.

Manipulation of weather might be possible by directing energy from space to drive it to a favorable purpose such as to make snow fall in Hellas, so that it could melt.  The use of dust may help nucleate dust as is desired, again perhaps Hellas.

It is just a proposal.  But you would have a whole lot of habitat in orbit of Mars and the conditions of that habitat may be favorable.

I think that developing the orbits of Mars and the surface of Mars should go together to go better.

Just one persons opinion.

Done

Last edited by Void (2024-05-17 09:56:05)


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