Terraforming putative Proxima Planet

Void · 2016-09-14 21:03:47

Not too much activity. Has everyone gone to the Moon?
https://www.bing.com/search?q=song+%22e … he+moon%22.

Void · 2016-09-14 21:25:39

Katabatic winds and white outs:
http://scientistatwork.blogs.nytimes.co … tica/?_r=0

Tom Kalbfus · 2016-09-15 01:00:37

I think the kind of technologies that can get us to Proxima, can do quite a bit towards Terraforming the planet Remember Forward's idea of a laser sail? Wha if we parked that behind Proxima to reflect light onto the dark side?

karov · 2016-09-15 07:39:20

Void wrote:

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.
-?

Well, tidal locking tends to extinguish not only axial rotation, i.e. diurnal cycle difference from year cycle ( libration or 'swindle' ), but also eccentricity ( elliptic orbits circularized ) and axial tilt ( i.e. 'noding'), too.

So most of the dwarf fusors' inner planemos shall be dull in these aspects.

But "most" in case of DOZENS of TRILLIONS of such per galaxy ... gives quite sizeable 'minority population' of 10exp12 - 10exp13 digits still.

karov · 2016-09-15 07:41:50

Tom Kalbfus wrote:

I think the kind of technologies that can get us to Proxima, can do quite a bit towards Terraforming the planet Remember Forward's idea of a laser sail? Wha if we parked that behind Proxima to reflect light onto the dark side?

Yeah!

That's what I'm 'insisting' on all the time.

With optics EVERYTHING from just a few stellar radii, to few light years is illuminable.

With simple mirrors and lenses ancient optics, not to mention lasers and more sophisticated tech.

Tom Kalbfus · 2016-09-15 07:56:47

karov wrote:

Void wrote:
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.
-?

Well, tidal locking tends to extinguish not only axial rotation, i.e. diurnal cycle difference from year cycle ( libration or 'swindle' ), but also eccentricity ( elliptic orbits circularized ) and axial tilt ( i.e. 'noding'), too.
So most of the dwarf fusors' inner planemos shall be dull in these aspects.
But "most" in case of DOZENS of TRILLIONS of such per galaxy ... gives quite sizeable 'minority population' of 10exp12 - 10exp13 digits still.

If the year is only 11 days long, seasonal variation wouldn't account for much anyway, a planet the size of Earth would take time to cool down and warm up. I don't think winters and summers that are 2 to 3 days long would do much.

Void · 2016-09-15 12:39:35

You guys are all saying things that I can agree are true to many cases, and likely so for Proxima b, however...:)

Proxima b could have resonance like or similar to planet Mercury. Or like Venus (Perhaps) it's atmosphere could have it in a slow spin (A theory says that is possible).

But let's suppose it will be tidally locked, I wonder if it is likely to have a steady state of thermal equalization between day and night side or a pulsing equalization. I tend to think it will pulse, and it may do so with a Oscillating time constant, which could be deviated from it's constancy by things like solar flares.

You could watch some of these video's if you have patience for it.
https://www.youtube.com/watch?v=vglUtBUWwNw

So, perhaps I might try to describe a possible sequence.

The oscillation would be between two extremes.
State 1: The sunward side has heated up as hot as it can get before the winds will trigger. The sunward side is depleted of moisture, so it will have less cloud cover. The dark side has dried out the atmosphere of the planet to it's driest, by the moisture condensing as snow and ice cap (Which can glaciate).

State 2: The winds are blowing at their maximum, snow is being blown off of the ice cap onto the day side, where it will tend to evaporate, and that evaporation will blow further towards the high noon side, and move upwards in the atmosphere, eventually contributing to increased clouds.

The whole planet cools down during the process of State 2, because the night side is still the night side, but winds are bringing moisture to the day side, causing more clouds to reflect sunlight.

Should State 2 continue long enough, many of the day surfaces will be cold enough for snow drifts, and so that is another way for water to move further into the day side.

Eventually, the moisture in the atmosphere on the day side should rain or snow out, further cooling the day side, and moisturizing parts of it such as mountains.

Eventually the temperature differential between the night and day side might equalize enough that moisture will no longer be blown into the day side as drifting snow, and evaporation, in the lower atmosphere, but the upper atmosphere should help to sweep the moisture back to the night side to fall as snow, and then the day side will clear of cloud deck, and will heat up again.

I can't guarantee that an oscillation will happen, but I am suspicious that it will.

A situation such as I have suggested, could also expand the habitable zone outward, because, if you presume a tidally locked red dwarf planet to have a average temperature of 0 Degrees C. at it's terminator, but you oscillate the temperature up and down by say 50 Degrees C, you then have a temperature range of + 50 to -50.

If your terminator average temperature was -40 Degrees C. you could similarly have a range of +10 to -90, which would still allow for periodic liquid water, and incidentally, "Dry Valley Lakes". (Ice covered lakes).

So, you see where I am going with this.

Another feature of such an oscillation, is that if somehow you could actually get to such a planet, during certain periods of the oscillation, the situration would be deadly without a good forcast and shelter, but in other periods of the oscillation, it could quite a pleasant environment.

Done.

Last edited by Void (2016-09-15 13:16:41)

Void · 2016-09-15 20:55:05

I was short for time on my last post, so I will patch it now if I can.

Slight mistake: I used and average of 0 DegC at the terminator for my argument.
That is an interesting argument as well, but I prefer 0 DegC at the high noon position.
This will be a cold planet. If I understand typical thinking, it would be at the outer edge of the "Habitable Zone", and we would be presuming a Earth similar atmosphere for greenhouse effect.

Maybe there will be an argument which proves me wrong, but for a tidal locked planet at the high noon position, where no wind is blowing, and there are little or no clouds in the sky, and with a 1 bar Earth similar atmosphere, I will presume that even at the luminescence of Mars, (Which is approximately our outer limit), heat will accumulate. Certainly surface heat does on Mars, in excess of the presumed limiting temperature of 0 DegC which is assigned to it.

http://www.space.com/16907-what-is-the- … -mars.html

In the case of Mars, it is a day night cycle with a thin atmosphere which apparently allows the surface temperatures to get as high as 70 DegF as a warmest case.

Anyway in full speculation, lets presume that the high noon position on a tidal locked planet is at 0 DegC average, and that thermal oscillations by way off Katabatic planetary weather cycles moves that up and down +/- 50 DegC.

Those are approximately temperature ranges familiar to parts of Siberia, where a thriving ecosystem can exist.

If you had a tidal locked planet (With a 1 bar Earth equivalent atmosphere), where the average temperature was -40 DegC at the high noon position, then if your high was +10.0 DegC and your low was -90 DegC, it would indeed be a challenging environment, but if moisture is provided to the high noon position, then it would still be one which for instance could support an Earth tundra analog ecosystem.

If you went even further, and had just the equivalent of 2 or so weeks out of a year, so for Proxima b, 4% of the time where water could melt, it would still be able to produce dry valley lakes with an ice covering. Unfortunately for such lakes, it might be more challenging to produce photosynthesis through the ice, except if they could work with part of the spectrum, (The longer) U.V. from flares.

Anyway, I wanted to demonstrate exceptions to the habitable zone defined.
Also, I note that such dry valley lakes on a Red Dwarf's planet would be adjacent in a continuum to underground oceans and aquifers as speculated for on Mars, and presumed on Europa.

A final note before I fade completely: The light spectrum of a Red Dwarf may not be as good to shine usable light through the ice of a dry valley lake, but my understanding is that it is much better at melting ice.

That's about it until my next bout of message board insanity.

Last edited by Void (2016-09-15 21:15:03)

karov · 2016-09-16 02:47:02

Tom Kalbfus wrote:

If the year is only 11 days long, seasonal variation wouldn't account for much anyway, a planet the size of Earth would take time to cool down and warm up. I don't think winters and summers that are 2 to 3 days long would do much.

Correct point, but I guess Void is right, that any kind of oscilations - no matter how subtle, weak and brief - would add up to create complex 'resonance' picture.

karov · 2016-09-16 04:05:11

It appears that these 'dull' eyeball planets are not so dull after all.
There is really extensive sci-tech literature covering suprisingly deep aspects of these.
On Arxiv only there are a > life-time-to-read-all amount of articles!
In fact eyeball ones - the simplest - are one just class of variety - and they have also massive complexity and variety, zillions of factors combining in zillions of ways!
Few examples.:

[1] https://arxiv.org/pdf/1411.0540v1.pdf

[2] https://arxiv.org/pdf/1412.5575v1.pdf

etc.

Imagination can't cope with the shear amount of eyeball ( in narrower sense ) and dwarf stars ( in wider ) possible arrangements!

Void · 2016-09-16 10:38:20

Very good stuff. At times it is a struggle to process, but glad you put it there.

Void · 2016-09-16 21:33:20

Karov,

I have reviewed the first document to the degree I could comprehend. I have some reason to apply a dispute to the presumptions of "Water Trapped" worlds which is depicted towards the end of that document.

You yourself pointed out that Katabatic winds can evaporate sections of ice cap even if they are in permanent shadow, and I have been pushing also the notion of wind blown snow.

The model I think is depicted is that for water to cycle on tidal locked planets, a polar ice cap must be extensive enough that it will glaciate past the terminator line and into the sunlight.

This is not required I think for both of the reasons previously mentioned.
1) Katabatic wind warming on descent, and evaporation of ice.
2) Wind blown snow.

This is a picture of a Martian polar ice cap:

Something like this is what I would expect to see on the dark side of a tidal locked planet where the night side is cold enough.
For Proxima b, I am a bit confused, if the planet is tidal locked and has a cold cap on the night side, then does it spin every 11.2 hours? To be tidal locked, and orbit Proxima Centauri, it must spin every 11.2 hours. So would the Coriolis Effect be even more than on Mars? And then actually, the spin axis is perpendicular to the sub stellar night spot isn't it. So, I'm not so sure about the pattern of ice cap with deep carved ruts in it, ruts carved by descending Katabatic winds, evaporating ice cap in certain lineal paths. Something more to learn here.

So, the etching pattern will be different, but I expect that it will exist.

So, lets presume a tidal locked planet with an ice cap with a thickness of perhaps 1/3 of the depth of the troposphere, for Earth, that is about 10,000 feet high (Sorry for the English).

Anyway if this cap only covers 1/2 of the night side, then we may think that this planet cannot have humidity on the day side as sunlight cannot reach any part of the ice cap.

For this model, blowing snow might not work as well as I might wish, (Just not sure), but Katabatic evaporation still might do some good.

If you have a boiling hot desert on the day side, and for a period of Earth weeks, a pool of very frigid air accumulates on the top of the ice cap, then an event triggering winds will unleash an evaporation method which may move humidity from the ice cap to the day side, and that humidity then floating upwards into the daytime atmosphere will encounter yet another reservoir of cold, cold from altitude.

Should the temperature differential be at maximum between the day and night side, (Similar to highest voltage in a fluctuating electrical circuit), then upon it's peak, energy of motion is created by the expenditure of energy differential. This then creates the fast winds.

Fast winds descending down the edges of the ice caps, pressurizes the air suddenly, heating it, and allowing it to evaporate ice into vapor into the flowing air. The low atmospheric air then enriched with humidity on the night side flows to the day side. There, it should accumulate as fog/clouds high in the atmosphere, to reduce the solar flux, and dampen the temperature differential between the day and night side. As that dampening overdrives, rain and snow might happen on the day side, particularly in the mountains.

So, I say. Maybe, in some cases. If the whole atmosphere pulses like an electrical LC circuit.

Maybe a repetitive cycling with an approximate time constant.

So there may be a way for tidal locked worlds not fully endowed with the necessary water to satisfy current speculation to wiggle out of the notion of being "Water Trapped".

Maybe

Last edited by Void (2016-09-16 22:04:04)

karov · 2016-09-17 04:07:40

Void,

Lotsa links here -:- http://worldbuilding.stackexchange.com/ … ked-planet

incl. about Coriolis, winds and precipitation.

Very interesting topic, in fact I'm very glad that the picture is SO complex and variable.

I'll diagonalize them all shortly.

karov · 2016-10-07 01:15:19

http://www.sciencealert.com/the-closest … d-in-water

Raft islands and continents.

Made by [astronomical] 'metals' mined outta the water.

Void · 2016-10-07 17:53:36

Interesting. I am not sure I understand what would go on in such a situation. The planet should be colder than ours, if I remember correctly, but we do not know what greenhouse effects it might have.
If an ocean planet, then lots of methods to equalize differential temperature.

Fluids would exist within the influence of two major gravity wells, Proxima b itself, then Proxima Centauri, the parent body.

One fluid, the air, if any obeys the rule that the colder it gets the heavier it gets, so it might be expected that it will try to flow to Proxima Centauri when colder and heavier, and so the warmer air would be displaced to the dark side of the planet by that process, of course winds.

Fresh water on the other hand is silly. Up cooled down to 39 degF (3.9 degC?) , it is at it's heaviest, but cooled more than that and it becomes lighter. And of course at 32 degF / 0 degF, it becomes ice and floats, on any liquid water that I am familiar with.

But then of course on an ocean planet, we should expect some salt in the water. Rain, and also dry places, where brine is generated by evaporation. And then possibly on the dark side, ice (Yes or No, depending how things are). Ice might also generate brine concentrate.

And brines have their own rules about what is heavier than each other, sometimes overwhelming the rules about temperature and density for fluids.

So, if that were not weird enough to try to imagine, I fear my mental model is insufficient by some factors.

The Coriolis force of course.

However, I am trying to visualize the balance of power between the gravity of Proxima b and Proxima Centauri's gravitation, and it's influence on the fluids previously mentioned. It may not be as simple as I previously thought.

So, the next weird thing, is I used to visualize a tidal locked planet as being like a glass of water with ice cubes floating in it. I supposed that the glass, being the planet with a water liquid layer surrounding it (simplistically), being in the gravity well of the parent star, the ice cubes would float in the glass to the top which would be similar to the dark side. So, I imagined that ice would then by gravitation congregate to the dark side by not just the cold temperatures imposed, but the specific gravity of ice being less than for any liquid water. I supposed however that cold wind storms would blow ice away from the dark side during storms.

I'm not so sure anymore. It seems to me that the dark side of the planet is actually traveling at a speed in excess of what is required to keep the whole planet in it's orbit. And then of course the day side is moving slower than what is required to keep the whole planet in it's orbit.

Something to work on. I'm baffled for now. Don't have it.

Last edited by Void (2016-10-07 18:19:59)

Tom Kalbfus · 2016-10-23 23:01:51

There is another way to terraform the planet

What if we take this idea, make it larger, and replace the Solar Flux tub illuminator and the fusion reactor with Proxima Centauri? What would you call it then? A famous science fiction writer wrote a novel about this sort of world. If Proxima b is like our World, it should have a lot of iron to build this world out of. and remember the metal tungsten has a high melting point.

Melting point
3695 K (3422 °C, 6192 °F)

Boiling point
6203 K (5930 °C, 10,706 °F)

Surface Temperature of Proxima Centauri
3,042 ± 117[10] K

The surface temperature of Proxima Centauri just happens to be below the melting point of Tungsten and carbon by the way. That means these materials can come in contact with the surface of proxima centauri and stay solid. Ergo, we can mine Proxima Centauri for building material, as well as volatile elements such as hydrogen, carbon, nitrogen, and oxygen, all to make our ringworld's atmosphere out of. Lets say wemade a scoop out of tungstein, mined from Proxima b and have it skim Proxima Centauri's atmosphere in an elliptical orbit with enough momentum so it makes it back out with some of proxima's atmosphere, cool it down and see what elements we have. The thing about Proxima is that convection is operative, so what is in its core can end up at its surface and vice versa. In this version of ringworld, the inner cylinder takes the place of the shadow squares, yet it is only about 500 km shorter in radius than the ringworld floor, enough so there is space between the inner cylinder and the atmosphere such that you could fly a spaceship between them in a vacuum. As it my artificial world idea, the inner cylinder is a holographic television or video screen, it produces an image of our sun appropriate for various latitudes on the ringworld's surface, it is a small ringworld. Proxima's bolemetric luminoscity is 0.0017 that of our Sun, by taking the square root and multiplying it by an astronomical unit, we can get a radius of it. 6,184,658 kilometers.

this ringworld would have a tangential velocity of 246.274 km/sec and it rotates once every 1.8263 days to get a centrifugal force of 1-g, its width would be the same as Proxima, about 0.282 the diameter of our Sun, which makes it 392,374.8 km wide. The inner cylinder shields this world from Solar flares, produces a convenient fictional image of the Sun. The radius I so large that there is no perceptible curvature between the ground sky. The sky appears normal, the image of the Sun rises in the east and sets in the west. Northern and southern latitudes are colder than the equator or is we wish, we could havemultiple equatorial, tropical, subtropical, temperate, subarctic, and arctic climate bands. Weather patterns won't resemble Earth, prevailing winds will tend to blow either due south or due north depending on latitude, as this spin of this artificial world is completely perpendicular to its surface, moving north or south produces no cyclonic vortexs, hurricanes jus don't happen here.

Void · 2016-10-24 17:44:12

Your notions are valuable in my opinion. I would not limit them to any one type of situation, but what comes to mind is white dwarfs. My understanding is that since their luminosity dwindles, the only way to have a civilization around them would be to have a giant spaceship which could move in as the heat dwindled.

Also, I am thinking about the Titanic. I would like to see compartmentalization, as a safety feature, and I wonder if you could come up with other safety features.

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

Habitability[edit]
It has been proposed that white dwarfs with surface temperatures of less than 10,000 kelvins could harbor a habitable zone at a distance between ~0.005 to 0.02 AU that would last upwards of 3 billion years. The goal is to search for transits of hypothetical Earth-like planets that could have migrated inward and/or formed there. As a white dwarf has a size similar to that of a planet, these kinds of transits would produce strong eclipses.[129] Newer research casts some doubts on this idea, given that the close orbits of those hypothetical planets around their parent stars would subject them to strong tidal forces that could render them unhabitable by triggering a greenhouse effect.[130] Another suggested constraint to this idea is the origin of those planets. Leaving aside in-situ formation on an accretion disk surrounding the white dwarf, there are two ways a planet could end in a close orbit around stars of this kind: by surviving being engulfed by the star during its red giant phase, and then spiraling towards its core, or inward migration after the white dwarf has formed. The former case is implausible for low-mass bodies, as they are unlikely to survive being absorbed by their stars. In the latter case, the planets would have to expel so much orbital energy as heat, through tidal interactions with the white dwarf, that they would likely end as uninhabitable embers.[131]

Debris disks and planets[edit]

The merger process of two co-orbiting white dwarfs produces gravitational waves
A white dwarf's stellar and planetary system is inherited from its progenitor star and may interact with the white dwarf in various ways. Infrared spectroscopic observations made by NASA's Spitzer Space Telescope of the central star of the Helix Nebula suggest the presence of a dust cloud, which may be caused by cometary collisions. It is possible that infalling material from this may cause X-ray emission from the central star.[122][123] Similarly, observations made in 2004 indicated the presence of a dust cloud around the young white dwarf G29-38 (estimated to have formed from its AGB progenitor about 500 million years ago), which may have been created by tidal disruption of a comet passing close to the white dwarf.[124] Some estimations based on the metal content of the atmospheres of the white dwarfs consider that at least a 15% of them may be orbited by planets and/or asteroids, or at least their debris.[125] Another suggested idea is that white dwarfs could be orbited by the stripped cores of rocky planets, that would have survived the red giant phase of their star but losing their outer layers and, given those planetary remnants would likely be made of metals, to attempt to detect them looking for the signatures of their interaction with the white dwarf's magnetic field.[126]

I believe that after Sol would become a white dwarf, some planets would be left over, and I would think that some of the objects would be rocky.

Where the white dwarf could be an energy supply for your habitat/spaceship, there would also be energy to be had from any gas giant planets, ice giant planets, and brown dwarfs that survived in that solar system. Giant floating robots harvesting wind and thermal energy?

And of course some day fusion. There should be left over ice bodies and perhaps planets with Hydrogen in their atmospheres.

And then maybe your method would also be good for brown dwarf solar systems.

I'm not saying not in normal solar systems, I am just saying it's special powers might be useful in the case of white and brown dwarfs.

And of course you and Karov like to think about mining stars anyway.

Last edited by Void (2016-10-24 17:54:14)

Tom Kalbfus · 2016-10-24 22:42:52

The nearest white dwarf is Sirius B, it is a bit further out than Proxima Centauri. My proposal is simply to use Proxima as an energy source, solar collectors on the star facing side of the inner cylinder would collect Proxima's energy, an use that to generate more white-yellowish light similar to our sunlight, there would be a fictional image of Earth's Moon or some other Moon, since this is an artificial world, tides can be simulated by pumping water into and out of holding tanks at the bottom of seas. The stars would be images of the actual stars as seen from Proxima. The stars you'd see in the projected night sky would be the stars you would see at underside of the opposite side of the ringworld from which you are standing. Stars would wheel around once every 1.8263 days, same as the rotation of the ringworld. It is a small ringworld compared to Niven's, but still plenty huge. It has the approximate surface area of around 30,500 Earths, About 1% of Niven's Ringworld. Still 30,500 Earth's worth of real estate is nothing to sneeze at, and red dwarfs are very common, and they can last for over one trillion years, not that we would likely be around for that long.

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