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#1 2019-02-05 13:11:12

Void
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Registered: 2011-12-29
Posts: 3,564

Rubble Piles, Asteroids, Moons, the inhabitation of.

I am really thinking Phobos, as the first effort.  A method for learning the method to inhabit and use such rubble piles.

It is not really a terraform, so I will do this here, as it does require an extensive "Life Support" in order to live inside/outside/and around such objects.

Some background on "Rubble Piles":
http://www.daviddarling.info/encycloped … eroid.html
https://en.wikipedia.org/wiki/Rubble_pile
Quote:

Moons[edit]
The moon Phobos, the larger of the two natural satellites of the planet Mars, is also thought to be a rubble pile bound together by a thin regolith crust about 100 m (330 ft) thick.[11][12] Spectroscopy of Phobos' composition suggests that Phobos may be a captured main-belt asteroid.[13][14]

Ok it is either a captured asteroid, or in part rubble from an asteroid and Mars.  In either case there may be hydrated minerals (Clays), Rare Earths, and perhaps heavy metals.  And it in itself, a method to have a habitation parallel to that of Mars, which also pioneers methods to inhabit and mine asteroids.

Maybe Phosphorous: https://scitechdaily.com/phosphorus-con … ar-system/

We know that quite a few people want to visit and inhabit Mars.  We do not know the health implications of the Martian surface and subsurface potential habitat locations.  We can speculate that synthetic gravity inside of a rubble pile, (Phobos), may give required or desired health benefits, and may provide material goods, and should show the way to inhabit other rubble pile objects.

Some plans from the Web:

This article shares a little, but not a lot.
https://www.newscientist.com/article/21 … e-station/
I am not really that interested in mounting engines on Phobos.

Well, that's good enough for now.

My version would have a triple shell method.
1)Outer shell (Inside rubble object), non-spinning, pressurized.
2)Vacuum shell inside outer shell.  non-spinning, evacuated to a rough vacuum.
3)Synthetic gravity shell.  Almost as big as vacuum shell. Inside of vacuum shell, pressurized, spinning.
*On the exterior of the rubble pile solar activated devices, also docking locations for spacecraft.
A magnetic field may be included, to help draw and hold human devices to the rubble pile.

My view is that for people like Jeff Bezos, Mars actually may provide a great environment.  That is materials from Mars itself being brought to orbit, and the two moons Phobos and Demos being available.

And of course Starship of SpaceX should be able to implement both habitation of Mars and Phobos, and maybe Demos.

Done

Last edited by Void (2019-02-05 13:37:03)


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#2 2019-02-05 18:25:48

SpaceNut
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Re: Rubble Piles, Asteroids, Moons, the inhabitation of.

Its sad that we do not have another launch vehicle readied with another insight and curiosity to send to the moons of mars....

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#3 2019-02-05 21:38:54

Void
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Re: Rubble Piles, Asteroids, Moons, the inhabitation of.

Yes, it is sad, but my thinking is that we have to be ready for contingencies.

It may be that at first certain long term medical results prohibit extended stays on Mars.  In that case we would provide for periodic stays on Mars for adults at least, and maybe even some children.  Maybe not pregnant women and young babies.  We don't know.

Having the ability to make synthetic gravity in orbit is the plan B that needs to be in place.

And as I have speculated, orbital Mars may be very important, for space to live and for minerals.

We may encounter a case where political forces can interfere with the emplacement of a settlement on Mars.  In that case, I would insist that the powers causing the trouble must pay for the alternative, to build habitat in conjunction with the Martian moons.

While it might be argued that there is a moral principal about planetary protection, there is also a moral principle about not consigning the human race to poverty and risk of extinction.  So, those who propose to have powers of ownership of Mars and other planets to use it according to their desires, must pay compensation to the interests of the human race, if they want to dilly dally pondering about life on other planets.  They are going to have to make a compromise, and they are going to need to pay for their intention to have power to restrict the human races progress.  They should not get what they want for free.  There are other interests to consider.  Important ones.

Should we not get satisfaction then I recommend rebellion.  Seriously.

At the minimum I want the Earth, Luna, Phobos, and Demos for the human race.  And really they are going to have to get off the pot and find their evidence of life on Mars.  They need to quit wasting our time.

I actually think that space medicine such as genetic overwriting of existing humans, (But not their germ line perhaps), and other space medicine will eventually make it possible for humans to have better health in low g situations, but I do fear the growing children will be much harder to revise.  I think that it could be that adults for the most part will live and work on Mars for extended periods.  But maybe procreation will occur in orbit.

Done.

Last edited by Void (2019-02-05 21:52:03)


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#4 2019-02-24 15:37:04

Void
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Re: Rubble Piles, Asteroids, Moons, the inhabitation of.

Here are materials on rubble pile asteroids that I easily accumulated with a simple query.  I have not reviewed it all yet, and so will.

https://www.bing.com/videos/search?q=co … &FORM=VIRE
https://www.nasa.gov/directorates/space … _with_AoES
https://en.wikipedia.org/wiki/Rubble_pile

But I will speculate on the origins of Phobos.  I am open minded.  It could be a splash off of Mars with an inclusion of C type asteroid, or a captured asteroid.

I will offer speculation on how a rubble pile asteroid could be captured into a circular orbit by tidal effects.  This is entirely speculation.  I do not present it as fact at all, but something that could be pondered.

Simply put, I think that the general difference in altitude between the Southern "Higher" hemisphere and Northern "Lower" hemisphere could do it.  I think that if a rubble pile moon travels in a circular equator orbit, will bleed off the least amount of orbital energy.

I feel that if Phobos had a polar orbit, since it probably is a rubble pile, it would encounter a higher gravity field when flying over the southern hemisphere than the northern hemisphere.  This should cause it to squeeze and then relax.  This also could perhaps suggest why phobos is less dense than rubble pile asteroids.  I cant say, but perhaps orbiting Mars will cause it to puff up more.

But really as a potential object to inspect and perhaps inhabit, I really don't see it as a show stopper any case which produced Phobos.

Done.

Last edited by Void (2019-02-24 15:43:13)


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#5 2019-02-24 16:52:50

Void
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Re: Rubble Piles, Asteroids, Moons, the inhabitation of.

OK, so I know just a little bit more.

I am attracted to Phobos.  I am not sure that I have a plan that would work, but I will propose one.  I think Phobos should be given a good look.

I currently think I like a pseudo "Starship" to start activity on Phobos.  I modification of it.  I have been following the teachings of GW about heat shielding for the ship.  I am glad he anchors us to reality.  Other than that I will not presume to judge SpaceX or Elon.  I guess the moral of the story is there can be a heat shield of some kind, but it will cost some trouble to produce it in reality.

As I have elsewhen here on this site suggested, I like the idea SuperHeavy to be coupled to an intentional mutation of Starship.  I would call that variant "Starshell".  It would be the 2nd stage, and unfortunately it will need a propulsion unit in order to complete to orbit of Earth, but then it may be practical to recover the propulsion unit to further use, so hopefully to avoid a cost which is excessive.

GW has proven to be very useful in instruction.  I believe he at one point suggested that two "Starships" coupled together end to end and spun could generate .5 g.  And so of course I want to link 2 or more "Starshells" into a synthetic gravity machine.  It is conceivable that "Starshell" could be as short as "Starhopper", and so maybe 4 of them linked could make a 1g max synthetic gravity baton.

I would not suggest this investment until an assessment of biology was made on the Moon.  Human biology of adults, and reproductive biology for small mammals.  Since it appears that the direction of space activities will include the Moon, then we should hope to profit the Mars effort this way.  Perhaps .5 g or some other value would be quite enough.  I am afraid I feel it may be unwise to assume that the human species can prosper in the ~.38 g field of Mars.  I don't like being a wet blanket, but it is quite an assumption to think so, after what has been learned about microgravity's effects on humans.  And we have not tested pregnancy or childhood either at this point.

Done.

Last edited by Void (2019-02-24 17:06:35)


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#6 2019-02-24 17:02:53

SpaceNut
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Re: Rubble Piles, Asteroids, Moons, the inhabitation of.

Mars’ Moon Phobos is Slowly Falling Apart. Orbiting a mere 3,700 miles (6,000 kilometers) above the surface of Mars, Phobos is closer to its planet than any other moon in the solar system. Mars’ gravity is drawing in Phobos, the larger of its two moons, by about 6.6 feet (2 meters) every hundred years. Scientists expect the moon to be pulled apart in 30 to 50 million years.

Your theory is contained in Phobos May Have Come from Massive Impact on Mars

THE COMPOSITION OF THE MARTIAN MOONS PHOBOS AND DEIMOS IN A GIANT IMPACT SCENARIO.

https://dailygalaxy.com/2018/09/endurin … nd-deimos/

THE COMPOSITION OF PHOBOS AND DEIMOS: CONSTRAINTS AND QUESTIONS.

So if it came from mars we will get a feel for what we might find is Global mineral distributions on Mars

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#7 2019-02-24 17:09:28

Void
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Re: Rubble Piles, Asteroids, Moons, the inhabitation of.

OK, thanks Spacenut.

It appears that rubble pile asteroids are presumed to have hydrated minerals in them in many cases.  This is because the parent asteroids would have had underground liquid water from the decay of an isotope of aluminum, and so clays would have formed.  impacts may also have created liquid water in them.  If Phobos is also in part made of Mars we might also presume that early Mars had clays as well.  But if not, Mars is near to get water from.  Not my greatest hope, but still a way.

While I understand that the Zubrinites on this site want Mars and Mars only, unfortunately that is not where the herd of cats wants to go.  Unfortunately that is not a process that can be enforced without dickering.  We can't just get what we want because we want it.

So, for Mars, you have to piggy back onto the direction that the cats want to go, since they are not inclined to be herded by goose step method.  To get your ducks in a row, you may have to swim how the ducks swim, and perhaps find a way to get your objectives included into the process.

We hope that synthetic gravity can simulate real gravity per reproductive needs.  We actually don't know that.  But I am willing to think it is likely.

My post #5 of this topic contains reference to "Starshell", which I suppose is my attempt to find a way to generate synthetic gravity machines from the spaceware that SpaceX currently proposes to create.  Of course I have asked for a mutation of it.

I hope for a chance to unify purpose in space.  The Zubrinites want Mars, and I have no intentions of getting in their way.  The Loonies want the Moon.  And the people who want asteroid mining want to do something like what I want to do with Phobos.  And of course there are those who what to block human access to Mars at all, or for a very long time.  I personally suspect the blockers as being Communist/Atheists who want to make a change in human religious philosophy.  I don't appreciate them trying to exploit human ambitions in order to establish themselves as the high priests of a new and evil religious order.  I do have reasonable sensitivity to the Mars life issue.  At some point a decision will have to be made.  Do or don't do Mars with humans.  But Mars may not be suitable for human offspring.  Nothing is tested or proven on that.

I'll be back!

Done.

Last edited by Void (2019-02-24 17:26:16)


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#8 2019-02-24 19:04:03

Void
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Re: Rubble Piles, Asteroids, Moons, the inhabitation of.

Oh, I bet I will catch some hell for this!

https://www.youtube.com/watch?v=ESQ1bKd7Los

Sanity check?

Well throw me out if you can't take a joke. smile


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#9 2019-02-24 22:01:23

Void
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Re: Rubble Piles, Asteroids, Moons, the inhabitation of.

So, by "Starshell", I desire components for space stations.  Granted some could be in LEO, some could go to NEO's, but for now at least I have some loyalty to the Mars dream.  So, I choose to explore the Phobos option.

How to get the shells where we might want them and then how to go from seed to blooming?

And as I have already said before, this is conversation not heresy.  That is unless there is a holy church of Mars this or that way.

We really don't know the dynamics of working with something like Phobos.  But I will start with the possibility that "Starshells" could be propelled to Mars orbit by efficient and effective methods whatever they could be.  Something to ponder.

The Earth has a magnetic field to protect space stations in LEO.  Mars has Phobos and Demos.   I am guessing that Phobos is the primary candidate. 

Maybe SpaceX will wave to us from the ground on Mars.  If so then congratulations!  It will be better for me to be judged a fool in that case.
Hurray for them then, and no feelings of the bitter.  Well done.  But, I am exploring plan "B".

Lets pretend that I have something to offer that you would ever really consider.

Well then these shells would achieve orbit of Mars.  Obviously directed propulsion would be a required component.  You may include methods of navigation that are popular as may achieve something of value to the purpose.  For me there is a preference for the use of ballistic capture methods, as these shells will be uncrewed I expect.  I understand that such a method as ballistic capture may or may not involve some interaction with the atmosphere of Mars.  I am ignorant on the bounds of those possible options.

In this, I make the case that I don't think there is a practical case for a small population of humans to flee to Mars and establish a heroic, valent republic of the free.  Ha Ha.  I do like representative republics though.

As always the vampires and demons will follow us wherever we may go.  They must feed off of the weak after all.  And they exist to prompt something better, however bitter that reality may be.  We will deal with the dead corpse zombies from the ancient world as long as we exist, but must always fight for the chance of new birth and life to exist.

So, as a "Dry Run" I speculate on methods to work with rubble piles.  And I don't expect to have achieved anything near perfection.  I am not a creature of perfection at all.  I do think I understand how to respond to stimulus.  I would rather gain than loose.  That should be a natural instinct I would think.

I by no means intend to establish a necessary set of methods.  I think this is such a alien way to live that we would be very stupid to impose rules at this point.  But if we could find worlds with materials useful and associate them with artificial manufactured worlds that simulate the reality that we have on Earth, I think this may be worth a look.

So the starting point would be a seed, or a birth if you prefer that.  Things sent from the Earth/Moon realm.  Those associated then with each other and in proximity with a Martian moon, probably Phobos.

The mature point would be a great city in orbit of Mars.

It's late.  I think that can be B.S.'ed about later smile :0 smile

Nite Nite.

Done.

Last edited by Void (2019-02-24 22:34:56)


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#10 2019-02-25 04:13:15

Terraformer
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Re: Rubble Piles, Asteroids, Moons, the inhabitation of.

Some thoughts from Hop David on the potential of Phobos - http://hopsblog-hop.blogspot.com/2015/0 … solar.html

Cities have almost always, with the exception of the last century, grown up around transport nexus's. Perhaps the main employment on Phobos will be in handling cargo that's going between interplanetary space and the Martian surface. There might be other opportunities in that - shipyards, refuelling etc. Maybe even reconditioning for those going from Mars to Terra, who will have to spend some time in higher gravity than Mars can provide.


"I guarantee you that at some point, everything's going to go south on you, and you're going to say, 'This is it, this is how I end.' Now you can either accept that, or you can get to work." - Mark Watney

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#11 2019-02-25 09:13:18

Void
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Re: Rubble Piles, Asteroids, Moons, the inhabitation of.

A very interesting set of materials Terraformer.  I will study it more.

Lots of things moving through my head.

A thing I would want to include would be a "World" magnetic field for Phobos.  This would serve many potential purposes.  Radiation protection could be a benefit for the surface of Phobos.  It might also tend to keep construction objects from be ejected into orbit.  And I think a very big thing would be to be able to modulate/throttle the size of the field.  In effect per the documents previous, Phobos is already the equivalent of a flywheel.  We may be able to make it into a motor as well, by selectively sailing on the solar wind.  This might allow PHobos to be sailed up or down in the Martian gravity well.  Within the limits of it's safety.

I would also want to encompass the entirety of Phobos with a cage.  It could be composed of electrical conductors, solar panels, struts, ect.  And it might be something to attach tethers to.  The cage then would also be a garage where you could service spacecraft and do construction projects, and perhaps some types of materials processing.  The cage would also serve to reduce the amount of space junk that might get ejected to orbit.  But you would want to consider the potentials for explosions.  That could really mess up the Mars orbitsphere.
Certain environmental conditions could be controlled in that garage.  The interior may have a moderated thermal environment.  Lighting might be controlled.  There should be some protection from micrometeoroids.

The magnetic field and tethers may each have the potential to extract gasses from the Martian atmosphere.  I do not stand against those who see tethers for deploying cargos.  They have covered that aspect well.  One thing that I have some concern for would be that by dangling a tether into the Martian atmosphere, their could be electrical discharges.

That could be interesting though, if you could keep it from wrecking your machinery.  That would be strange if you could get an electric current between the two bodies.  The friction of your "Probe" in the atmosphere would then slow Phobos down in it's orbit.  Also if you could capture atmospheric gasses from Mars to Phobos, that would lower down the orbit of Phobos.  But since we would turn Phobos into a solar sailing motor, it could speed back up and climb to a higher orbit.

And that could suggest another toy.  Perhaps part of Phobos could be constructed into a big space hab with lots of inertia, and it too could have a magnetic field and tether, but since it would be constructed of processed materials that are much stronger than a rubble pile, and since it would be smaller, perhaps it could fly down to 50-100 miles over the surface?  Much smaller tether then.

As far as Phobos and Demos themselves, I am wanting to see if they would have needed materials.  Rare Earths, Platnum Group and Gold, Water.  And of course there should be common construction materials.  Very likely they will contain fragments of the crust of Mars from long ago that will have value for science.  Water could occur several ways.  But Tars, and Clays seem like something that could be possible.

My thinking is that if Mars/Phobos/Demos gets going well, then more people and materials will arrive from the Earth/Moon.  Then the empty cargo space going back might bring useful mined materials back to the Earth/Moon.

Mars is going to need some of those materials as well.

As for habitats in orbit, I still like a low g outer shell, with interior spinning synthetic gravity machines.  I intend that each of them would have vacuum bells around them, probably just a bit larger than the spinning hab.  The interface between the low g non spinning portion, and the spinning portions might actually just be a sort of airlock(s) at the rotation points.  There would be air seals where the joins at the bearings would be.  In this setup, even if the seals sprung a leak, the volume of the vacuum chamber would not be enough to cause deadly harm to the inhabitants.


…..

I am away that all of this is very grandiose.  The picture painted is the a partially thought out version of a possible desired outcome.  And so would be the Point "B".

But we need a Point "A" to start from as a "Seed Method", and that has to be able to grow and metamorphically evolve through many changes to achieve something like what can be suggested as a point "B".

Done.

Last edited by Void (2019-02-25 13:43:08)


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#12 2019-02-25 11:40:14

tahanson43206
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Re: Rubble Piles, Asteroids, Moons, the inhabitation of.

For Terraformer:

Thank you for this (impressive to me) blog sequence from Hop David.  Because I've been trying to understand how a tether might support sailplane excursions to the atmosphere of Mars to deliver or to pick up packages, I was interested to see that possibility mentioned.

A useful figure provided is a taper ratio of teflon for a tether of 11.  I gather that that tether would reach to the surface of Mars.

The blog sequence also considers the eccentricity of Phobos orbit, and the presence of mountainous terrain along the equator of Mars.

This is a great find!

(th)

Terraformer wrote:

Some thoughts from Hop David on the potential of Phobos - http://hopsblog-hop.blogspot.com/2015/0 … solar.html

Cities have almost always, with the exception of the last century, grown up around transport nexus's. Perhaps the main employment on Phobos will be in handling cargo that's going between interplanetary space and the Martian surface. There might be other opportunities in that - shipyards, refuelling etc. Maybe even reconditioning for those going from Mars to Terra, who will have to spend some time in higher gravity than Mars can provide.

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#13 2019-02-25 12:41:06

tahanson43206
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Re: Rubble Piles, Asteroids, Moons, the inhabitation of.

Continuing from #12 .... One of the five concerns addressed in the Hop David blog is the contamination levels of perchlorates in the Martian regolith.  He characterizes Mars as a "superfund" site, along the way.

Before undertaking this post, I ran a search on the forum for "perchlorate and harvest".  That combination does not appear to exist, but there were several posts containing the word perchlorate, and one (by Void) which included consideration of exploiting perchlorate.

I'd like to toss into the hopper here the possibility of a full time full force mining operation to recover oxygen from perchlorate, and export the chlorine, or (perhaps) to find a non-injurious use for it.

This activity would (I presume) be carried out some distance from places of habitation.  The export of oxygen would have economic value for sure, and it is likely someone will think of an application for the chlorine.

The activity of extracting perchlorate from regolith would (presumably) lead to economic activity related to other compounds found in the regolith, some of which (I gather) would also have economic value.

(th)

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#14 2019-02-25 13:51:33

Void
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Re: Rubble Piles, Asteroids, Moons, the inhabitation of.

Again Terraformer, thanks so much.


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#15 2019-02-25 15:44:47

Terraformer
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Re: Rubble Piles, Asteroids, Moons, the inhabitation of.

And that could suggest another toy.  Perhaps part of Phobos could be constructed into a big space hab with lots of inertia, and it too could have a magnetic field and tether, but since it would be constructed of processed materials that are much stronger than a rubble pile, and since it would be smaller, perhaps it could fly down to 50-100 miles over the surface?  Much smaller tether then.

For a tether, longer is better. If you're orbiting 100 miles up, you're moving at orbital velocity. If you're orbiting at 1000 miles up, a tether dropped down to 100 miles will be moving significantly slower than orbital velocity at its foot - it has the same rotational period around Mars as your counterweight, but the path is smaller. Which is why the required delta-V to dock with the tether is lower.

If the tether tip is only going at 0.6km/s, building a robust reusable rocket vehicle to dock with it would be a lot easier than building one that can reach orbit. The cost of getting stuff off Mars could get quite low. Maybe even enough that water could  be  economically mined from it (though I will hopefully ensure that's not the case, by undercutting such suppliers with my Cererean Water Company and our elevators).


"I guarantee you that at some point, everything's going to go south on you, and you're going to say, 'This is it, this is how I end.' Now you can either accept that, or you can get to work." - Mark Watney

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#16 2019-02-25 18:17:49

SpaceNut
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Re: Rubble Piles, Asteroids, Moons, the inhabitation of.

Part of the issue is topic creep when trying to find a key word such as perchlorate search
It is one of the contaminants that effect growing of food and getting onto you so clean is a requirement of suits used for EVA's.

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#17 2019-02-25 19:05:34

Void
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Re: Rubble Piles, Asteroids, Moons, the inhabitation of.

SpaceNut,

Um....I am sure that the regolith of Phobos and Demos will require some cautions on toxic effects.  It is conceivable that some perchlorates might be present.  We don't know the exact composition of the parent bodies.  Is there some other thing you want to draw attention to on this topic?

Life support is sort of an odd place for this except my aim in dealing with small bodies such as rubble piles, is to make them into life support machines of great complexity.  I guess you could move this to some other section if you want to.

Done.

Last edited by Void (2019-02-25 19:08:51)


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#18 2019-02-25 19:11:25

Void
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Posts: 3,564

Re: Rubble Piles, Asteroids, Moons, the inhabitation of.

Terraformer,  I see what you are getting at, (I think), but would like to argue that we may be splitting hairs over apples and oranges smile

Please review what I will say, and give me back what I need to improve my grasp.

Quote:

And that could suggest another toy.  Perhaps part of Phobos could be constructed into a big space hab with lots of inertia, and it too could have a magnetic field and tether, but since it would be constructed of processed materials that are much stronger than a rubble pile, and since it would be smaller, perhaps it could fly down to 50-100 miles over the surface?  Much smaller tether then.

For a tether, longer is better. If you're orbiting 100 miles up, you're moving at orbital velocity. If you're orbiting at 1000 miles up, a tether dropped down to 100 miles will be moving significantly slower than orbital velocity at its foot - it has the same rotational period around Mars as your counterweight, but the path is smaller. Which is why the required delta-V to dock with the tether is lower.
If the tether tip is only going at 0.6km/s, building a robust reusable rocket vehicle to dock with it would be a lot easier than building one that can reach orbit. The cost of getting stuff off Mars could get quite low. Maybe even enough that water could  be  economically mined from it (though I will hopefully ensure that's not the case, by undercutting such suppliers with my Cererean Water Company and our elevators).

Let me start by saying what I think you described.

Rotating Skyhook:
-A sub-orbital rocket launch.  At its height it will be going slower than a circular orbit.  In my view orbits have energy of altitude, and energy of motion.  In a non circular orbit there is an oscillation where at the apex (Apogee) it will be moving slower than would a object traveling in a more circular orbit where altitude does not change.  So, to grab it with a tether, I think you have to have a rotating tether, one that rotates in the same direction of circle that the flywheel/momentum anchor orbits.  This then causes the tether hook end to have a better chance of connecting with the ballistic rocket at its apogee without intolerable differential speed.  So the hook is traveling backwards relative to the direction of orbit.  That must be sufficient in speed to compensate for a shorter tether.

Non-Rotating Skyhook:
Must be longer so that its hook speed will as I think you indicated match the rockets apogee speed at the point of interception.

Space Elevator as a Non-Rotating Skyhook:
And then we can probably argue that a space elevator is probably the longest sort of non-rotating skyhook we might care to think about.  And probably not think about because for Earth and probably Mars it requires too much effort for the probable results.

…..

I am really happy about the work you guys are doing on Skyhooks for manipulating "Solid" objects.  But I am of another sort on this.  What I want to manipulate is Atmosphere, Ions, and Plasma if possible.  So this could loosen or change the rules for the types of implementations that I want to try.

I think to begin, I will describe a atmosphere capture device.  Should we lower a tube down into the thinnest heights of the atmosphere, we might get away with a fairly large differential speed between our "Hook" and the item we want to hook.  If we only use vacuum from the top, that will do us no good.  But lets suppose that we can send power through our tether and our tether is a serial set of tubes with air pumps between them.  Or if you like maybe just one ram intake at the bottom so that even though you are at the high altitudes of the atmosphere, I will just say 50 miles, I think you can get what I am after.  You could choose what works.  On Mars that changes a lot.

So, you have this scoop, and a differential speed between the scoop and the item to pick up which is atmosphere.  If you can pressurize the lower end of the tube-tether to 6 mb, then you can probably make the atmosphere rise more then 50 miles up the tube, as actually the gravitation will fall off a bit traveling 50 more miles up.  And then so you would hope to condense this gas using any means possible.  Compression or cold and Else.  Maybe a combination.  As you suck atmosphere up, your apparatus will loose orbital altitude and perhaps speed.  My plan is to have a magnetic field that gets pushed by the solar wind, to give make-up energy to the whole process.  The magnetic field will be throttled up and down, depending on if the wind is at your back (More Magnetic Field Then), or against you (Less Magnetic Field Then.  It is even possible that you might manipulate the magnetic portions of the plasma of the upper atmosphere, with your magnetics.  But that wanders from my current paragraph's apparent method.

Actually I am not that serious about the last paragraph.  It is an interesting illustration of what I want, but I think real implementation will require a different sort of tether.

For now I can think of perhaps three methods to struggle with.

1) Lower a device on a tether, into the atmosphere, that will adsorb atmosphere into a substance.  Pull it up and desorb the molecules, repeat.  I am not so sure that is practical.  Maybe with a rotating tether.  It dips down adsorbs gas, rotates up, the you desorb the gas and somehow deliver the gas to a storage device.  I suppose your device might be able to travel to the hub periodically for this delivery of gasses.  I don't really think this is what I want, but it needs to be kept on a chalk board somewhere in the mind, for the possibility that someone will make a variant of it that could actually be practical.

2) Electrical Tethers: (I don't feel I have a full grasp of this, but I am interested in struggling with it further).
https://www-istp.gsfc.nasa.gov/Education/wtether.html
Here I think we might be dealing with Ions.  If we suck ions up to the main body of the device electrically we will loose share orbital energy with the accumulated mass of the Ions.  If we instead push Ions down electrically, we can boost the orbit energy.  That is what I think so far.  But I want to accumulate mass, I want (+) ions to travel up, I think.  If that generates electrical power but puffs up the mass then I hope that that situation will be handled around Mars, by the modulated Magnetic sail of the parent device in the solar wind.  We may get away with that for Mars and Venus, if we can surf/sail on the interface between atmosphere and solar wind.  There is a problem though, as I want to collect this mass of electrically charged ions.  That requires some further research, think.  I am guessing it can be done, but if you are lifting up (+) Ions where do you get electrons for them?  If somehow if you can lift up (-) Ions, then I suppose you can use an electron gun to shoot electrons at the lower atmosphere to get rid of them.  I don't feel I have complete comprehension of what might go on with this.  More is needed.  And then if you electrically neutralize your ions to normal atmospheric gas, how do you compress this lean, thin substance?  I have thought of https://en.wikipedia.org/wiki/Piezoelectricity.  Piezoelectric actuators to compress gasses already attracted to a capacitive/Condenser surface.  And that is as far as I have come on this one.  Can anyone help?

3) If we are Surfing/Sailing on the interface between atmosphere and solar wind with a modulated magnetic field, then we might have access to upper atmospheric plasma, existing due to the space environment.  A can we find a way to magnetically reconnect to this magnetic substance, de-energize it to gasses and compress it?  That one is really at the edge of my comprehension so far.  I do wonder about it.

……

Looking forward to feedback.

Done.

Last edited by Void (2019-02-25 20:07:27)


I like people who criticize angels dancing on a pinhead.  I also like it when angels dance on my pinhead.

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#19 2019-02-25 20:47:37

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 19,929

Re: Rubble Piles, Asteroids, Moons, the inhabitation of.

Not quite enough details for the nasa link on the drag length as its not known if its a loop or an unterminated end of a cable.

Here are a couple more links on its effect, just have not had the time to read through them...
https://opentextbc.ca/physicstestbook2/ … ional-emf/
https://opentextbc.ca/physicstestbook2/ … magnetism/
https://en.wikipedia.org/wiki/Electrodynamic_tether

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#20 2019-02-27 22:09:22

Void
Member
Registered: 2011-12-29
Posts: 3,564

Re: Rubble Piles, Asteroids, Moons, the inhabitation of.

KBD512, I have taken something from you.  Liked it so much I also put it here.
https://www.nasa.gov/sites/default/file … apture.pdf
I believe you supplied it in your post #213 of "Index
» Human missions
» Starship is Go...".

Some things I took away from it is that the magnets don't have to be cryogenic, or maybe I misunderstood.  And space radiation problems are partially solved with it.

I will be back, with a shark....

Here it is, and it is in association with someone named Zubrin???  And what is this "Planetary Society".  Sounds snobbish to me.
https://www.nextbigfuture.com/2017/09/i … rence.html


The "Z" associates with the "MuskTusk".  I just don't think we know all things.  We are given crumbs of information, and that is good, because it means that there may be something bigger.  And I like the sound of that.

Anyway, while SpaceX appears to be working on a Rocket Jockey trip to Mars, which I do not mind.  I hope they can pull it off, but there is this other material that suggests a different method, visiting orbit first, and I would say seeing what Phobos and Demos have to offer, but not forbidding Mars.  And I will say will say two strange phrases "Ballistic Capture" and "Aerocapture" (With Plasma bubbles).  I love it.

So, then lets do something, don't mind surprises.

Done.

Last edited by Void (2019-02-27 22:22:27)


I like people who criticize angels dancing on a pinhead.  I also like it when angels dance on my pinhead.

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#21 2019-02-28 19:32:48

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 19,929

Re: Rubble Piles, Asteroids, Moons, the inhabitation of.

Its sort of like putting the capsule in a balloon which is HIAD where the increased surface area provides the entry atmospheric aerobraking. It would increase payload mass to the surface.
The plasma will need to have a permability like steel so that the ac rf energy can line up the field lines.
This was also noted in one of the nasa documents post along time ago but so far I do not think its been built to test.

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#22 2019-03-04 19:53:39

Void
Member
Registered: 2011-12-29
Posts: 3,564

Re: Rubble Piles, Asteroids, Moons, the inhabitation of.

Rubble pile asteroids.  Just an article related to the idea.

https://phys.org/news/2019-03-asteroids … ought.html

Sounds like even rubble pile asteroids may retain a big piece of the original core which may then draw the rubble back after a collision, hiding the core.

One possible nature of Phobos could resemble this, I am guessing.

Done.


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#23 2019-03-27 20:04:00

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 19,929

Re: Rubble Piles, Asteroids, Moons, the inhabitation of.

Was looking for another but this will do as HUMAN SPACEFLIGHT: PHOBOS BASE

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