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#26 2016-09-04 12:40:15

Tom Kalbfus
Banned
Registered: 2006-08-16
Posts: 4,401

Re: Terraforming putative Proxima Planet

Void wrote:

I think the greatest danger of solar flares is that the worst ones are speculated to be damaging to any ozone layer, and after that, life on the day side would be at risk of U.V.  So, if that is so, the danger would be after the flare.  And that presumes that you would have a ozone layer in the first place.  On the other hand it is supposed that Mars had Oxygen in it's atmosphere when it was younger, that from the splitting of water molecules by U.V. light.  Oxygen in the atmosphere might promote the formation of an Ozone layer then.  So, a flare might destroy ozone which would facilitate the formation of more Oxygen, and the more Oxygen would facilitate the formation of ozone, so, it's possibly a double edge sword.  Maybe you could have a N2/O2 atmosphere without life.

...

Sectioning off the dark side ice cap, I then ponder the Katabatic winds.
https://en.wikipedia.org/wiki/Katabatic_wind
https://en.wikipedia.org/wiki/Katabatic … ind_hg.png

The Katabatic winds would be periodic, and could sweep very fine cold snow into lower areas, such as open water, and if the ice cap margins were grounded against a lowland area suitable it might even sweep the snow into those, and some of those might even be on the day side near the terminator.  I suppose to a limited extent, snow might even travel uphill like sand dunes to the day side, provided the winds were fierce enough, and until the dunes reached a location where they would melt.

This and direct evaporation from open water or ice, and the possibility of an Earth model ocean spillage/circulation would provide moisture to the atmosphere, and in the case of snow pushed by winds, a direct source of melt water for rivers and streams.

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

The average depths of the troposphere are 20 km (12 mi) in the tropics, 17 km (11 mi) in the mid latitudes, and 7 km (4.3 mi) in the polar regions in winter. The lowest part of the troposphere, where friction with the Earth's surface influences air flow, is the planetary boundary layer. This layer is typically a few hundred meters to 2 km (1.2 mi) deep depending on the landform and time of day.

So based on this, how high can an ice cap be on Proxima b?
The planet will have greater gravity, so the ice will flow more like a pancake, glaciers flowing faster I presume, if other conditions are similar to Earth.  Total amount of water.  For now I presume that the amount is proportionally similar to Earth.  However many thinkers think that such planets will have a relatively reduced amount of water.  I think that water may be conserved well on such planets if it were there in the first place.

So the next question is how high can water vapor go as a rule.  For Earth we might think 7 km (4.3 mi) per the article linked to.  So, the higher the ice cap, the more limited it is in receiving water vapor for snow on it's plateau.

And then there is the continental base.  For the Earth model, Antarctica would help to isolate part of the ice cap from the presumed oceans.

For the Mars model, grounded ice would have no continent under it.  It is possible that liquid water would exist under all portions of the ice cap, so it would be on banana peals so it really might pancake out over the ocean basin, and not be as high.

So how would we go about terraforming this planet so humans could more easily live on it?

Would a tidally locked planet with a red sun be a problem for human inhabitants?
Should we try to fix that?
What about shielding from Solar flares?
Maybe we could put a large physical object at the planet's L1 point that selectively blocks solar flares.
Also what could se do about the night side. Maybe we could place giant mirrors in polar orbits around the planet, maybe by using light sails that got us to this system in the first place. Just some ideas I'm throwing out there. If we blocked off direct light to Proxima b and set up mirror satellites in 24-hour polar orbits we could have Earth like days. But of course those polar orbits would either have to change their orbital planes rapidly, or we need multiple mirrors that are selectively reflective and non-reflective, since the year is only 11.2 days long.

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#27 2016-09-04 14:06:23

Antius
Member
From: Cumbria, UK
Registered: 2007-05-22
Posts: 1,003

Re: Terraforming putative Proxima Planet

Tom Kalbfus wrote:
Void wrote:

I think the greatest danger of solar flares is that the worst ones are speculated to be damaging to any ozone layer, and after that, life on the day side would be at risk of U.V.  So, if that is so, the danger would be after the flare.  And that presumes that you would have a ozone layer in the first place.  On the other hand it is supposed that Mars had Oxygen in it's atmosphere when it was younger, that from the splitting of water molecules by U.V. light.  Oxygen in the atmosphere might promote the formation of an Ozone layer then.  So, a flare might destroy ozone which would facilitate the formation of more Oxygen, and the more Oxygen would facilitate the formation of ozone, so, it's possibly a double edge sword.  Maybe you could have a N2/O2 atmosphere without life.

...

Sectioning off the dark side ice cap, I then ponder the Katabatic winds.
https://en.wikipedia.org/wiki/Katabatic_wind
https://en.wikipedia.org/wiki/Katabatic … ind_hg.png

The Katabatic winds would be periodic, and could sweep very fine cold snow into lower areas, such as open water, and if the ice cap margins were grounded against a lowland area suitable it might even sweep the snow into those, and some of those might even be on the day side near the terminator.  I suppose to a limited extent, snow might even travel uphill like sand dunes to the day side, provided the winds were fierce enough, and until the dunes reached a location where they would melt.

This and direct evaporation from open water or ice, and the possibility of an Earth model ocean spillage/circulation would provide moisture to the atmosphere, and in the case of snow pushed by winds, a direct source of melt water for rivers and streams.

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

The average depths of the troposphere are 20 km (12 mi) in the tropics, 17 km (11 mi) in the mid latitudes, and 7 km (4.3 mi) in the polar regions in winter. The lowest part of the troposphere, where friction with the Earth's surface influences air flow, is the planetary boundary layer. This layer is typically a few hundred meters to 2 km (1.2 mi) deep depending on the landform and time of day.

So based on this, how high can an ice cap be on Proxima b?
The planet will have greater gravity, so the ice will flow more like a pancake, glaciers flowing faster I presume, if other conditions are similar to Earth.  Total amount of water.  For now I presume that the amount is proportionally similar to Earth.  However many thinkers think that such planets will have a relatively reduced amount of water.  I think that water may be conserved well on such planets if it were there in the first place.

So the next question is how high can water vapor go as a rule.  For Earth we might think 7 km (4.3 mi) per the article linked to.  So, the higher the ice cap, the more limited it is in receiving water vapor for snow on it's plateau.

And then there is the continental base.  For the Earth model, Antarctica would help to isolate part of the ice cap from the presumed oceans.

For the Mars model, grounded ice would have no continent under it.  It is possible that liquid water would exist under all portions of the ice cap, so it would be on banana peals so it really might pancake out over the ocean basin, and not be as high.

So how would we go about terraforming this planet so humans could more easily live on it?

Would a tidally locked planet with a red sun be a problem for human inhabitants?
Should we try to fix that?
What about shielding from Solar flares?
Maybe we could put a large physical object at the planet's L1 point that selectively blocks solar flares.
Also what could se do about the night side. Maybe we could place giant mirrors in polar orbits around the planet, maybe by using light sails that got us to this system in the first place. Just some ideas I'm throwing out there. If we blocked off direct light to Proxima b and set up mirror satellites in 24-hour polar orbits we could have Earth like days. But of course those polar orbits would either have to change their orbital planes rapidly, or we need multiple mirrors that are selectively reflective and non-reflective, since the year is only 11.2 days long.

Look at the way we do things here on Earth.  We do not (or at least have not so far) attempted to change the climate of places like Norway or Canada to make them more tropical.  Instead, we adapt ourselves to local conditions.  It is always easier to add insulation to a building than to attempt to heat the entire atmosphere using orbital mirrors.  In my opinion, this is how human beings will go on working, because it is always so much easier to adapt to the broad parameters of an environment than it is to change them to support you.  Just a hunch, based upon the reality that human beings are inherently short term, lazy creatures.

If the proxima planet does turn out to be a solid world with an arid sun facing side and ice covered dark side, then the hot side will be used for such things as agriculture and solar power.  The night side may be the place for industry, with lots of cheap land that isn't useful for much else.  If the night side hosts an ice cap kilometres thick then melting it might not be a good idea.  Without knowing anything about the place we really are shooting in the dark making any judgements at all when it comes to how we best use the environment.

Last edited by Antius (2016-09-04 14:16:41)

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#28 2016-09-04 22:00:05

Void
Member
Registered: 2011-12-29
Posts: 6,976

Re: Terraforming putative Proxima Planet

I am perhaps 90% in agreement with you Antius.  But for adaptation, the winds of such a world would be both a threat, and a gift.  The night side could very likely in places be quite a good place to have gardens under artificial lights on the surface or in mostly underground buildings.  The power should be relatively cheep, and the ability to convert power to useful light is getting better all the time.

If the day side is environmentally stable enough for agriculture, then fine, but my understanding is that there is concern that a flare could zap the Ozone, and so, then potentially famine for short term thinkers.

On the other hand if you can grow crops 3 time periods out of 4, and the fourth one is a disaster, you could buffer that problem, because you would have a natural deep freeze at the dark side midnight.  But that would work for a more sensible species.

We know what would really happen if you are dealing with humans.  Some brilliant idiot would find a way to spend down the reserves, and look like a financial genius.  And then Oops!

Last edited by Void (2016-09-04 22:01:29)


Done.

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#29 2016-09-04 22:36:50

Tom Kalbfus
Banned
Registered: 2006-08-16
Posts: 4,401

Re: Terraforming putative Proxima Planet

I think by the 22nd or 23rd centuries, when we visit this planet, humans aren't likely to be the only intelligent inhabitants of Earth and the Solar System. We will create another "race" of intelligent artificial life forms, and the will have a lot to do with getting us to Proxima b.

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#30 2016-09-05 14:16:53

karov
Member
From: Bulgaria
Registered: 2004-06-03
Posts: 953

Re: Terraforming putative Proxima Planet

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#31 2016-09-05 14:34:47

karov
Member
From: Bulgaria
Registered: 2004-06-03
Posts: 953

Re: Terraforming putative Proxima Planet

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#32 2016-09-05 21:01:21

Void
Member
Registered: 2011-12-29
Posts: 6,976

Re: Terraforming putative Proxima Planet

Antius and Karov,

I like where you are headed.  I think much too much people look at another world, and think "It's not as good as Earth for this item or that item", but they don't see where it might be better than Earth for other items.

Sort of like:
For most animals a woodtick is quite an annoyance, but for a chicken, perhaps it is something to eat, an opportunity, not a problem.


Done.

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#33 2016-09-06 03:57:03

karov
Member
From: Bulgaria
Registered: 2004-06-03
Posts: 953

Re: Terraforming putative Proxima Planet

btw, what comes to my mind.:

[1] this http://orbitsimulator.com/formulas/hillsphere.html , shows that the Hill sphere of Proxima b is with radius of 150 000 km.

Enough for a moon it seems? Or double mutually tidally locked planet - rearranging the inner system into planetary 'couples'? wink

[2] the shear IMPORTANCE, VALUE and UBIQUITY of |proxima b|'s as galactic real estate!

The more realistic and recent calculations of the mass of the Milky way imply that the number of stars ( https://en.wikipedia.org/wiki/Fusor_(astronomy) ) in it is in fact way-WAY into the TRILLIONS!

That means trillions of red dwarfs alone.

And as with the example of https://en.wikipedia.org/wiki/Gliese_58 … ary_system , they all have compact , neat , close, convenient , multiple planetary systems.

I.e. TRILLIONS of rocky planets with longevity of few trillions to hundreds of trillions of years.

Within radius of under 1 million light years from our home.

[3] As I many times insisted - terraformation is ALL about (surface) GRAVITY.

We are bottom crawlers. All we need is:
- solid surface to walk on,
- flooded into breathable atmosphere and
- illuminated properly.

water bodies come secondary for weather, climate, biospheric, aesthetic reasons.

Every other 'ingredient' in the land-making recipe is easy having the gravity.

You either use.: [1] natural one where available, within human hospitable limits around 1g, or [2] if excessive you decrease it via going up via orbital rings over the underbody , or [3] if lower or missing - you create it or amplify it via rotation.

Appropriate gravity is plentiful at red dwarfs. The smaller the stars due to the lesser mass and size of the initial formation proplyds = the smaller their planets, too.

Their giants are like our Neptune & Uranus, their mid-sized ones are of Earth-Venus caliber.

I.e. surface gravity-wise the red dwarfs planetary formation is like a natural attractor for making planets of the 1 G surface gravity range. ( See.:  http://www.google.bg/url?sa=t&rct=j&q=g … MxYpwZulEw  of Gerald Nordley's )

At least a FEW (!) 1G-ish planets comprising their inner systems per red dwarf.

( infra-system inter-planetary transport would be eased in a great degree due to deeper stellar gravity well - for faster trans-orbitals, closer distances ... the planets within a red dwarf system would be like the continents from this map - lBHNtcj.jpg - in travel times using even primitive solar sailing ships ... )

Biospheric construction materials are absolutely ubiquitous. Even if a Poxima b-like red dwarf planet is totally volatiles boiled off early in its making - the red dwarfs systems are small, the frostlines and cometary hallos are just a few AU away, so volatile import from their outer systems is easy and cheap if needed. The stars themselves are close, small and magnetic enough to be ram-scoop mined easier then the bigger sun-like stars. If necessary at all.

Moving masses up and down the stellar gravity well would provide also the torque and momentum to change orbits and axial rotations, although this is economically acceptable only if its a spin-off / by-product of ther necessary activity. I.e. acceptable ONLY if it separately brings added value on the table.

Changing orbits and rotation IS NOT necessary, though.

For proper illumination ( luminosphere ) - OPTICS is enough. The stellar source is near and plentiful.

SO, for strictly speaking terraformation, in the classical sense - i.e. turning natural rocky planets into earth-likes the red dwarfs are god's gift, a bounty.

Last edited by karov (2016-09-06 04:14:03)

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#34 2016-09-06 15:02:34

karov
Member
From: Bulgaria
Registered: 2004-06-03
Posts: 953

Re: Terraforming putative Proxima Planet

Antius wrote:

Look at the way we do things here on Earth.  We do not (or at least have not so far) attempted to change the climate of places like Norway or Canada to make them more tropical.  Instead, we adapt ourselves to local conditions.  It is always easier to add insulation to a building than to attempt to heat the entire atmosphere using orbital mirrors.  In my opinion, this is how human beings will go on working, because it is always so much easier to adapt to the broad parameters of an environment than it is to change them to support you.  Just a hunch, based upon the reality that human beings are inherently short term, lazy creatures.

If the proxima planet does turn out to be a solid world with an arid sun facing side and ice covered dark side, then the hot side will be used for such things as agriculture and solar power.  The night side may be the place for industry, with lots of cheap land that isn't useful for much else.  If the night side hosts an ice cap kilometres thick then melting it might not be a good idea.  Without knowing anything about the place we really are shooting in the dark making any judgements at all when it comes to how we best use the environment.

Antius,

Agree. Our body size is quite compact. For multi-billion populations we need far-far less than a planet-wide terraformed-habitat.

Even Earth consists of mostly literally dead zone for humans.

A dry hot variety of red dwarf tidally locked "eyeball planet"

5405_ca6ab34959489659f8c3776aaf1f8efd.jpg

i.e. day-side hemisphetic scale 'Sahara' and night-side hemispheric wide 'Antarctica'

will give us a ring of Mediterranean size seas as glacial crust compression lakes

plus

DOZENS of ... Niles, Tigrises, Euphrates, Induses, Ganghes ... flowing nightsideway from the lakes to (as further into) dayside til complete evaporation... as eyeball veins.

http://nautil.us/blog/forget-earth_like … ll-planets

But the story doesn’t end there. When a layer of ice gets thick enough, its bottom layer melts from the pressure. This causes the ice to flow downhill, like glaciers do on Earth. So a hot eyeball planet’s thick night side ice cap spreads out and slowly flows toward the day side. There may be a trickle of water that flows into the light to be evaporated all over again. Our models project that there are characteristic wind patterns that pile clouds up in a specific region on the night side (gory details here). The planet’s non-uniform appearance can really look like an eyeball. Rivers that flow from the night side to eventually evaporate on the day side might even look like veins.

Where on a hot eyeball planet could you live? It’s a classic Goldilocks story. The day side is roasting and dry. The night side is frigid and icy. In between, it’s just right! The sweet spot—let’s call it the “ring of life”—is at the terminator, the boundary between night and day. The ring of life is bounded by deserts on one side and ice on the other. There is a constant flow of water from the night side to the day side—a series of rivers, all flowing in the same direction. The Sun is fixed in the sky right at the horizon, and the area is in permanent light. Conditions are pretty much the same all the way across the ring of life. One can imagine vegetation following the rivers onto the day side until they dry up, with different ecosystems interspersed along the way. There could be mountains at the edge of the ice sheets, since the ice-covered continents would be heavily weighed down.

Each of these river valleys maintaining many dozens to up to hundreds of millions of people.

Egypt_2010_population_density1.png

or

158178-PAK749_Pakistan_Landscan_Population_A3_L_20130826.png?itok=1lHax2M3

Even on present day level of technology. And most developed nowadays nation's living standards wink

Imagine tens of nations* the size of Egypt, Pakistan, India, Indochina, Mesopotamia on such planet.

I mention *nations* cause various cultural traits people would still tend to live together and they usually do not need entire planet to territoriality-differentiate from each other.

As much or more than the total present day population of the Earth.

Linear habitable patches - ideal for transport purposes, square power more efficient then 2D grids.

The national borderlines will eventualy extend from day-pole / cis-stellar point , to night-pole / trans-stellar point.

Like the modern day Antarctic claims cake-cuts wink

Plenty of hydro-power, from nightside, plenty of agri- and solar from dayside.

Massive icy heat sinks into the nightside.

Last edited by karov (2016-09-06 15:14:52)

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#35 2016-09-06 22:54:41

Void
Member
Registered: 2011-12-29
Posts: 6,976

Re: Terraforming putative Proxima Planet

Your thoughts are entertaining Karov.  Don't forget about wind blown snow as a source of rivers.
Some things go unsaid smile


Done.

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#36 2016-09-07 13:49:38

karov
Member
From: Bulgaria
Registered: 2004-06-03
Posts: 953

Re: Terraforming putative Proxima Planet

Void,

the deeper one looks - the more (details).

Trillions are the new billions, you know.

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#37 2016-09-09 22:13:37

Void
Member
Registered: 2011-12-29
Posts: 6,976

Re: Terraforming putative Proxima Planet

Processing....Processing.... smile


Done.

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#38 2016-09-11 20:59:29

Void
Member
Registered: 2011-12-29
Posts: 6,976

Re: Terraforming putative Proxima Planet

Terrestrial red dwarf planets, are some of my best imaginary entertainment.  Do I think the universe was constructed so that we could jump between stars, and Jedi night light saber battles (Pre-historic urges) with other bipedal or semi-bipedal beings, no, and I appreciate that the universe does not favor such silliness and cruelty.

But the imaginary calculation of how some worlds around red dwarfs can be often is very entertaining in my spare time. 

Since this section is for terraforming, I will focus on that.  Supposing you could get to a red dwarf world, and it had qualities we did not favor, then terraforming might change that.

In the case where it might have deficiencies of water and atmosphere, where those are locked on the dark side, but not entirely, where the world had a thin atmosphere, but larger potential resources on the dark side, obviously greenhouse gasses or your weather machine could be just the trick.  At the very least super greenhouse gasses would warm up the lower layers of the atmosphere, and still not necessarily warm up the higher layers too much.

A planetary civilization should certainly be capable of pumping water from the dark side to the day side, to also modify the characteristics of the planet.  I think that red dwarf terrestrials, in some cases maybe be more easy to manipulate than say a planet like our Earth around sol.

Last edited by Void (2016-09-11 21:07:35)


Done.

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#39 2016-09-11 21:10:21

Void
Member
Registered: 2011-12-29
Posts: 6,976

Re: Terraforming putative Proxima Planet

I'm also going to suggest a very interesting variation of a water world, an ice world, and suggest why I think it could be habitable well outside of the so called habitable zone, or could be made so rather easily.

First of all I am going to B***H a bit.

Snow Ball Earth.  "If it ever happens, we don't know how it gets out of it". Duh! 

Red dwarf water world, "If they ever freeze over, we don't know how they would get out of it".

The answer in many cases is sublimation pits!  Sublimation Pits!

Logically, within limits dust, either volcanic or cosmic, will flow by winds, on a freeze dried planet preferentially to the low spots, and will embed preferentially in the warmer spots.

If the Earth had become locked in a snowball configuration, then you can bet that even if it's temperatures were Antarctic even at the equator, sublimation would occur, and the troposphere, to the degree there could be one under those conditions, would assist sublimated vapor to condense in higher areas, vertically higher, and latitude higher, in the case of Earth.  This process would cause a positive feedback where the pits etched, would become warmer, because of a thicker layer of atmosphere collecting over the evolving pits, and also dust of whatever kind would tend to collect in these pit bottoms, tending to make them more absorbent of sunshine.

Similar stuff for a Red Dwarf ice world.  Really a beautiful concept.  Imagine a single pit on the high noon side of an otherwise glacial planet.

This will of course have variation dependent on the amount of ice.  Not enough, and the day side is a dry day side, even far outside the habitable zone.  But I specified a glacial world, so instead, presume that there is enough ice to cover an Earth similar, but Red Dwarf world 20,000 feet (Sorry for the units).

We then have to account for mountains, plateaus, basins, winds, and the solar flux of a location.  Also we have to account for distance from the star, and of course the greenhouse characteristics of the atmosphere.

If it is a cold glacial world, then we cannot assume that CO2 will rescue the situation, at least in the case of a tidal locked world.  The CO2 will tend to accumulate on the dark side, like it accumulates in the south polar ice cap of Mars.

I am going to speculate on such a world, where the front side of the eyeball planet will be a sublimation pit, and by atmospheric displacement, some very interesting things could happen, to make the planet habitable, at least in the sublimation pit.

Of course there can be variations of this that are not tidal locked, particularly for cold worlds outside the typically attributed habitable zone, and I will eventually try to describe how those variations might look.

I think that it is just possible that Mars in it's younger days may have behaved like such a world.  I'm not saying it did, I am saying it might have tended towards such attributes, even as it does today.

If we wanted to, we might imagine how Saturn's moon Titan might respond to Saturn becoming a very dim Red Dwarf (Just entertain me, I am fully aware that it cannot).  And ignore the fact that this situation would eventually strip away Titans atmosphere, I am just trying to make a visual model for a Earth sized ice world around a red dwarf star, quite far out from a habitable zone as it is typically designated.

As it is now, without a imaginary red dwarf Saturn, sublimation of ice, and I think also CO2 cannot occur in the atmosphere of Titan.  But, if Saturn were suddenly to become even a very dim flare star, this situation for such a tidal locked object could change.  At the very least during flares, sublimation might occur at the high noon location.

A visual for Titan:
http://www.nasa.gov/mission_pages/cassi … 0223L.html
625458main_titan20120223L-43_946-710.jpg

Although the use of Titan as a model of a icy "Terrestrial" world, deviates from the typical concept of "Terrestrial", it is very entertaining to me to visualize how such a model where the object is a full sized planet around a red dwarf star, might behave, well outside the "Habitable" zone.

In this case, for this Ice/Water world, a conflict will try to resolve itself.  A sublimation pit should form, but glaciation should also try to close the sublimation pit.  Then you must add in the probability that dusty and rocky material will line large areas of any sublimation pit, due to wind borne deposits, glacial deposits, and sublimation/evaporation.  Granted Titan has no terrestrial volcano's, but remember that rocks and dust and also organic materials which resemble that will likely accumulate in any such sublimation pit which might occur.

If you really did have a very large oversized Titan, perhaps in some cases the "Sublimation Pit" would reach all the way down to the underground ocean, but I think that might only be in some cases.  Otherwise, you would have a pit which appears much like land, because of the rocky and organic overburden in the low areas.  Boggy situations would also be favored, if you had Earth like plant life. 

This is getting long so I will try to get into a condensed version from here.

In the sublimation pit you could have a troposphere, even if in the icy areas of the planet you only had pressures similar to the Earths stratosphere (Maybe just a bit more that that).  This would conserve energy for the planet, since, the "Stratosphere +" would be capable of keeping N2 as vapor on the dark side, but might not keep water and CO2 as vapor on the dark side.

Glaciation would then provide liquid water and vapor CO2 to the day side sublimation pit, provided that a sufficient glacial deposit existed more or less planet wide, and that glacial deposit was significantly impregnated with dry ice (CO2).

The CO2 would tend to stay in the sublimation pit for a while before freezing again in the colder portions of the glacial planets stratosphere.

I said also I would try to imagine non tidal locked worlds.  Those come in many varieties.  Some with a slow spin, and perhaps some with a Earth like or even faster spin.  Some with and without moons of significance.  Examples: Earth with Moon, Mars without significant moon(s).

For an Earth like planet with a significant moon, I would imagine, a sublimation pit which encircled the equator, but was modified by objects of elevation such as Tibet.

For a Mars like planet (Sized up), I would imagine that the sublimation pits would migrate slowly with the variations in the tilt of the planet.

Done.

Last edited by Void (2016-09-11 22:04:42)


Done.

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#40 2016-09-12 02:45:04

karov
Member
From: Bulgaria
Registered: 2004-06-03
Posts: 953

Re: Terraforming putative Proxima Planet

Void wrote:

I think that red dwarf terrestrials, in some cases maybe be more easy to manipulate than say a planet like our Earth around sol.

I absolutely AGREE. A short / incomplete list of advantages.:

- tidal locking makes easier to devise the optical systems ( aerostatic or statite ones ) to optimize the luminosphere, also cold trapped on night side volatiles easier to move to dayside then to import from off-planet. Optical distro planning and holographic management easier when the planet under does not move in respect with the primary lightsource...

- shorter in system distances. (!!!) for every purpose: to mine the star for all kind of materials, to import from beyond the frostline, to place orbital and statite structures, space elevators, kinetic structures ... even for shorter old fashion Hofmans - deeper into gravity well the better ... to place Optics again - parasols, difusing soleta lenses, L1 swarms... everything.

- 1G-ish ready and ubiquitous - no need to span orbital rings to decrease gravity by/on 'upper floors'.

- bigger number of compact placed 1g-ish planemos to work with and eventually to swap masses ( volatiles for metals & rocks etc.)

- long life. Proxima will shine as it is onto 'b' for 4 000 000 000 000 years! about 1000 TIMES longer then the Earth lifespan up to now. ( So long that the very planet will start 'spoiling' but geophysical refreshment quite achievable and handy indeed )....

... you add more

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#41 2016-09-12 03:21:19

karov
Member
From: Bulgaria
Registered: 2004-06-03
Posts: 953

Re: Terraforming putative Proxima Planet

Void wrote:

Snow Ball Earth.  "If it ever happens, we don't know how it gets out of it". Duh! 

Red dwarf water world, "If they ever freeze over, we don't know how they would get out of it".

The answer in many cases is sublimation pits!  Sublimation Pits!
...

Done.

I'm a fan of partially terraformed habs ( shorthand of 'habitat' ) because one does not need all the 1G-ish equipotential surface to be consumed by human livable land.

Perhaps the reason to be fan of this is emotional and prejudicial - wink cause simply we inhabit such place where REALLY INSIGNIFICANT part of the good-gravity space actually consists of good LAND. Most of it is either hanging in the air or above it, or is covered with miles and miles of rock or water or ice, or is non-solid surface in the best case. Even the solid grounds are mostly deserts - icy or dry, or high mountains etc. SO, 'partial' is 'natural'. The innate aesthetic criteria are met. We DO LOVE boundaries of our Lands.: be it rivers, cliffs, high peaked ranges, ocean water ( see Polinesia ), gasbag walls of a plate or strip Birchean supramundane habitat, the caps of a rotating space colony ... All-livable-land-around-only kinda hurts our territorial safety animal instincts wink

So, may be this is what makes appealing a livable terminator belt of a dry/hot eyeball dwarf planets, or a livable valley pit surrounded by ice cap ...

This is the reason why I suspect that the future owners of these realty dev sites ( and red dwarf planets are the most ubiquitous, easier to handle, longest living, correct-G habs ) will not tend to terraform them in their entirety, but will follow the mega-pattern.: a human hab is homes taking small part of the land, which on its own turn takes small part of the whole hab space available. We do not build over every square inch of our gardens / yards / plots. We do not cover with city all of our countries ... ( even Singapore and Vatican are not a single or merged buildings ... even if we go the arcology way - the indoors designed are so huge that they imitate outdoors ... )

We by heart, by instinct consider always the gradation .: indoors -> outdoors -> hinterland -> wilderness ->  outback -> void ... where each consequitive 'layer' is exponentially larger.

SO, to come back to the point.:

Sublimation pits lands or spot lands onto icy eyeball planets won't be built outta kinda 'luminospheric' scarcity considerations.

There is PLENTY of star light to get rid of if fusor too close ( down to few fusor radii ), i.e. within the inner rim of goldilock zone or to put back together ( up to few light years! ) if light source too far, way out of external boundaries of classical HZ.

So considering 'concentric layers of homey-ness instinct" it shall be islander mentality designed. This is the design pattern drive, not resources of light etc.

AND there are LOTS of ways to build land.:

- floating sun-bathed islands on a icy eyeball planet 'bottomless' ice-free spot-ocean.

eyeball_earth1.jpg

5406_ee389847678a3a9d1ce9e4ca69200d06.jpg

orrrr, without to melt down the ice - cover it with dirt, insulation layers, rocks ... it is not necessary a planet to get warmer with depth wink

like a raft on a frozen pond.

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#42 2016-09-12 07:42:27

Void
Member
Registered: 2011-12-29
Posts: 6,976

Re: Terraforming putative Proxima Planet

Karov,

Very good, from my point of view.  I am glad that we have many areas of convergent thinking.

....

Of course, to go out from the star and out of it's habitable zone is to risk atmospheric collapse by dark side condensation, but the further outward, then the more likely for a spinning planet, and one that has much ices.

A stars snow line:
http://www.space.com/33410-star-snow-li … -time.html

For our solar system, a theory has it that a planet tried to condense at the asteroid belt, but Jupiter's influence stopped it.

Water for Earth to some extent is thought to have come from the asteroid belt comets, and not outer system comets.  So, if we suppose that there is an overall randomness in how a solar system condenses, the "Butterfly Effect", then things might have turned out different.

So, if Jupiter had not sucked up as much stuff, and disrupted things, perhaps a terrestrial at the asteroid belt, Mars as an ~Earth sized planet, and Earth with a different amount of water, possibly more water, possibly less.  For Venus, perhaps a similar evolution to what it has had, perhaps not.

So, if you might have a "Terrestrial +" planet which starts to develop towards becoming a gas giant, but stops, because of a lack of sufficient materials, in some cases at the asteroid belt, I speculate that you could have a very icy terrestrial, "Terrestrial +".

And for Mars, it could be much larger than it is, and behave much as previously hinted at, where sublimation pits could provide life zones.

As for an Earth/Moon analog, depending on the solar flux, it could much resemble as it is now, or in a colder cases, perhaps a sublimation/evaporation ring around the equator, with the most habitable parts of the ring being below "Sea Level", in fact perhaps all the way down to an ocean bed.

In such a solar system, possibly Mars as ~Earth sized, and with an unknown volume of ice.  If it had significant ice, I would expect sublimation pits that would wander with the axial tilt, since this Mars would be presumed to have not significant moon.

As for a "Terrestrial +", an Earth like planet in size, but presumed to have far more ice, if it escaped becoming a mini-Neptune, by starvation of Hydrogen and Helium, I will speculate that it could also provide habitable pits, by the process of the pits themselves, and by the process of accumulating atmosphere, which would not be dissipated unless some liquid water process such as running rivers, could dissipate it.

Although I have an attraction to tidal locked planets, for this thinking, as they would be found further out, most of them might be spinning, which of course greatly reduces the chances of atmospheric collapse from cold.

It also greatly improves the chances of the worlds having been close to or in the snow line, and it greatly reduces the chance that the parent star would have stripped away the planets atmosphere.

Done.

Last edited by Void (2016-09-12 08:02:31)


Done.

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#43 2016-09-12 08:34:19

Tom Kalbfus
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Registered: 2006-08-16
Posts: 4,401

Re: Terraforming putative Proxima Planet

If Proxima b is a water planet, that means it is likely less dense, since its mass is greater than Earth, this is good news if you are worrying about greater gravity. A less dense water planet would be larger than Earth, and could have a surface gravity that is equal to or less that Earth. A larger planet would mean more living space in which to live on. Since the planet is further from its Sun, a greater portion of it will be covered in ice. The ice will likely extend across the terminator over to the day side. This would take the form of sea ice rather tha ice bergs, since those are formed on land. fresh water would come from rain and snow. I'm not sue how salty a global ocean would be.

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#44 2016-09-12 09:26:33

Void
Member
Registered: 2011-12-29
Posts: 6,976

Re: Terraforming putative Proxima Planet

This thread is about that specific planet, and not about the generalized notions that Karov and I have been speculating on.  In the possible case you speek of, for a water world, we have to wonder how flooded it would be.
You seem to indicate all the way flooded.

I can see how a cold ice flooded world might manage to sequester excess CO2 as ice, and how it might benefit from excess N2, up to a limit of 10 bars.  (Baked out Venus seems to have about 3.5 bars of N2).  Such an icy world might also sequester atmosphere using river sedimentation, in favored spots. 

I have been told that Earth sequesters excess atmosphere into sedimentation of rivers.

I am not sure that a water world of the type you suggest can protect itself from becoming a run-away Venus.
I am also not saying it can't, I just am not aware of how.

As for how Proxima b would get that much water, what I have read is that it could have accumulated it at the snow line when it formed, and then it could have migrated inwards.

I myself am hoping for a cold terrestrial or two, further out.


Done.

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#45 2016-09-12 21:31:14

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: Terraforming putative Proxima Planet

Hubble's Best Image of Alpha Centauri A and B

ooalphacentauri.jpg

I do not believe that the little red dot to the left of A is an artifact.....

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#46 2016-09-12 22:01:39

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,782
Website

Re: Terraforming putative Proxima Planet

SpaceNut wrote:

I do not believe that the little red dot to the left of A is an artifact.....

droolies.GIF

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#47 2016-09-13 01:26:02

karov
Member
From: Bulgaria
Registered: 2004-06-03
Posts: 953

Re: Terraforming putative Proxima Planet

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#48 2016-09-13 14:53:20

Void
Member
Registered: 2011-12-29
Posts: 6,976

Re: Terraforming putative Proxima Planet

Karov showed:
main-qimg-8dce062e37d405b789ee03a53cb3a4c9?convert_to_webp=true

Very entertaining.  I feel that such a world however might have periodic episodes of wind storms, punctuated by calms.  Say perhaps each 2 weeks long.  This would mimic what Antarctica does some times.

So, for such a world, a "Boiling Hot Desert" coupled with a extremely frigid dark side would create a severe differential pressure, and when that let loose, your boiling hot desert would suck in a giant pool of frigid air from the dark side, and that with it would drag very large amounts of fairy dust snow.

So, although I am not certain, I think that the day side of any such planet has means to be periodically watered by such storms with dusty snow.  Therefore I think their might be periodic blooms in the deserts, if there were plants, and also I believe that when that snow melted/evaporated, the secondary consequence would be increased rain/snow in any proximate mountain range, perhaps even under the noon high position, if the mountain were high enough for those precipitations to happen.

Keep in mind that those winds could be hurricane force speeds at times.

th?&id=OIP.Mb38fd278f88465ab10ea290d26334a7co0&w=300&h=226&c=0&pid=1.9&rs=0&p=0&r=0
th?&id=OIP.Me1c04f0e871d7991752dd75e9d03ce86o0&w=300&h=225&c=0&pid=1.9&rs=0&p=0&r=0
th?&id=OIP.M54b1e8bd2b0660662ee6c2ae7cc9d1b0o0&w=299&h=187&c=0&pid=1.9&rs=0&p=0&r=0

So, the day side could be watered by glaciation, and periodic Katabatic force wind blown snow.

The wind blown snow may be able to penetrate into the dry land much more than the glaciers, during the storms.  (That is if a process similar to Antarctica occurs).

Last edited by Void (2016-09-13 15:39:36)


Done.

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#49 2016-09-14 07:55:34

karov
Member
From: Bulgaria
Registered: 2004-06-03
Posts: 953

Re: Terraforming putative Proxima Planet

Void,

https://en.wikipedia.org/wiki/Katabatic_wind#Impacts

but they are quite dry!

They blow snow like desert winds blow dust / sand.

I.e. in order to be snow for blowing out there must be constant snow replenishment, i.e. as you say the dayside deserts to not be so deserty after all.

Katabatic mechanism may in fact make sure that all the loose frozen water is quickly returned back into the daylight?

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#50 2016-09-14 10:53:52

Void
Member
Registered: 2011-12-29
Posts: 6,976

Re: Terraforming putative Proxima Planet

This is all my speculation.  I speculate for the entertainment of it, and in the hopes that when better scientific measurements are possible, some additional things to test/check for can be identified.

I am glad you choose to consider the thoughts of the last post Karov.

A cold tidal locked planet is less likely than a hot one, due to the difference in the distance to the parent star.

But for this, it is easiest to think about it as tidal locked, and without Coriolis effect.

But then after that you do have to factor in all the possible variations.
-Coriolis effect.
-Spin rate.
-Tilt of axis.
-How circular is the orbit.
-Nature of the atmosphere.
-Flare activity.
-?

Starting with the simplest model:
-Katabatic Winds. (Ice erosion from it as well).
-Land Slide Run-outs. (Slurry from avalanche of snow involving vibration and air mixing as a fluidization process).
-Dune fields.
-Slurry (Fine snow air).
-Siphon.
-?
The above are things we have witnessed on some planets.  I think under optimal conditions they could work together to help to moisturize the dry parts of such planets.

I will try to apply a greater efficiency to keep this shorter.

I think the temperature build up, cold on the ice cap plateau, and hot in the sunward basins, would build up until the difference was enough to overcome  barriers to air flow.  Barriers might exist because of natural mountains, and also because snow will fall preferentially nearer the edges of the ice cap.  But the remaining moisture might condense further inside the ice cap, as a finer snow.

I expect that the Katabatic wind might be triggered periodically by this buildup, and then it would behave in the manner, as you described.  It would cut "Dry Valley Channels".  As the winds released the "Gravitational Energy", in the correct situation, the winds would draw air from the interior, and if those winds were sufficient they would build a "White Out", which would be a slurry of air and fine snow.  This getting to the edge of the precipices would fall by gravity, and would be even heavier than the very cold air.  It might in some ways begin to resemble a talcum powder avalanche.

We are talking about hurricane force + winds after all, at max.  Plus such a planet would have an engine which would be gigantic compared to the Antarctic/Greenland models.

Such planets might have thicker atmospheres as well, so that can be taken in consideration also.

If a plume of super cold air were to suddenly begin to fill a hot basin, I do not think it would take long for portions of it to get cold enough for wind blown snow to remain frozen.  Then you could consider snow being transferred further by wind blown dunes.  Mars has wind blown dunes, and here we might be talking atmospheric pressures from 250mb to 10 bar, maybe more, possibly moving at hurricane speeds at times.

Now you might consider what would happen on less simple models of such planets where you have variations of combinations of:

-Coriolis effect.
-Spin rate.
-Tilt of axis.
-How circular is the orbit.
-Nature of the atmosphere.
-Flare activity.
-?

smile

Last edited by Void (2016-09-14 11:12:54)


Done.

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