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For bodies in the Kuiper Belt, sunlight intensity is around 0.1% that at Earth orbit. This would appear to make the prospect of solar power extremely difficult. However, research into solar sail technologies suggest that it should be possible to produce extremely thin solar sails constructed from aluminium, with mass of 1 gram per square metre. KBOs with a diameter of 100km, would have only ~0.1% of Earth gravity and gravity declines with square of distance from the centre of the body. A solar concentration disc constructed at the poles of such KBO could be built to truly enormous scale and could track the sun as the body rotates. A mirror with a diameter 100km would concentrate some 10.6GW of heat. A thermodynamic powerplant would convert this heat into electricity, with low grade waste heat being dumped into the ice of the KBO. This would gradually melt the ice. Eventually, the KBO would differentiate into a rocky centre, a warm water mantle and an icy crust.
The pressure at depth 10km would be ~1 bar. Such a body could support an aquatic ecosystem if humans were to provide the light required to drive the ecosystem. Convection within the water would be weak, due to the weak gravity and the ice sheet floating on the ocean could be many miles thick. Both would provide a lot of insulation. This would allow the ocean depths to remain comfortably warm, whilst the surface temperature of the ice remains at temperatures <100K. Human settlements could be constructed on or beneath the icy crust. Likely, humans would live in rotating buildings within an otherwise low-g environment. The aquatic ecosystem would provide food and would absorb wastes and waste heat from the human habitats. With gravity being 1000x weaker than Earth, it would also be relatively easy to create open air spaces within the mantle. Bouyant forces wouod be almost negible and the pressure gradient very shallow. Thin walled vessels made from thermo plastics could enclose habitable spaces, which are anchored either to the core or to the ice above.
The first attempt at this type of terraforming would probably be the Trojan asteroids, many of which appear to be captured centaurs. The outer moons of Jupiter and Saturn appear to be icy as well. At Jupiter distance from the sun, sunlight is 5% Earth intensity. So our concentrating mirror woukd gather 50% as much heat as it could at Pluto distance. The outer asteroid belt is dominated by C-type bodies, which are also water rich. Hygiea appears to be a water dominated body.
https://en.m.wikipedia.org/wiki/10_Hygiea
Last edited by Calliban (2023-02-21 07:27:19)
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I value the information you provide.
I came across this yesterday: Asteroids:
http://newmars.com/forums/viewtopic.php … 92#p206392
Quote:
Since this topic is active, I guess this could be pinned to it: https://phys.org/news/2023-02-unknown-c … roids.html Quote:
FEBRUARY 20, 2023
Unknown class of water-rich asteroids identified
by Marietta Fuhrmann-Koch, Heidelberg UniversityImage Quote:
I wish they would describe some of the new class of object better.
Quote:
At the same time, the infrared spectra support conclusions as to the bodies’ chemical and mineralogical composition. Just like Ceres, there are minerals on the surface of the discovered asteroids that originated from an interaction with liquid water.
The small astronomical bodies are quite porous. High porosity is yet another characteristic shared with the dwarf planet Ceres and an indication that the rock material is still quite original.
“Shortly after the formation of the asteroids, temperatures were not high enough to convert them into a compact rock structure; they maintained the porous and primitive character typical of the outer ice planets located far from the Sun,” explains Dr Wladimir Neumann, a member of Prof. Trieloff’s team. He was responsible for the computer modelling of the thermal development of the small bodies.So, they might be like porous rock sponges with ices in much of the pore space?
Maybe the Trojans of Jupiter tend to be of this sort.
Done.
It suggests a different "Goldilocks Zone", one for emerging space faring cultures.
I suppose ignoring the Earth/Moon, it starts at Mars/Phobos/Deimos, and extends to Jupiter-Trojans-Callisto.
This is a general area where you can get rocky and icy materials in useful quantities, in my opinion.
Quote Calliban from previous post:
The first attempt at this type of terraforming would probably be the Trojan asteroids, many of which appear to be captured centaurs. The outer moons of Jupiter and Saturn appear to be icy as well. At Jupiter distance from the sun, sunlight is 5% Earth intensity. So our concentrating mirror woukd gather 50% as much heat as it could at Pluto distance. The outer asteroid belt is dominated by C-type bodies, which are also water rich. Hygiea appears to be a water dominated body.
https://en.m.wikipedia.org/wiki/10_Hygiea
You might also look at 24 Themis: https://en.wikipedia.org/wiki/24_Themis
Quote Calliban:
For bodies in the Kuiper Belt, sunlight intensity is around 0.1% that at Earth orbit. This would appear to make the prospect of solar power extremely difficult. However, research into solar sail technologies suggest that it should be possible to produce extremely thin solar sails constructed from aluminium, with mass of 1 gram per square metre. KBOs with a diameter of 100km, would have only ~0.1% of Earth gravity and gravity declines with square of distance from the centre of the body. A solar concentration disc constructed at the poles of such KBO could be built to truly enormous scale and could track the sun as the body rotates. A mirror with a diameter 100km would concentrate some 10.6GW of heat. A thermodynamic powerplant would convert this heat into electricity, with low grade waste heat being dumped into the ice of the KBO. This would gradually melt the ice. Eventually, the KBO would differentiate into a rocky centre, a warm water mantle and an icy crust.
The pressure at depth 10km would be ~1 bar. Such a body could support an aquatic ecosystem if humans were to provide the light required to drive the ecosystem. Convection within the water would be weak, due to the weak gravity and the ice sheet floating on the ocean could be many miles thick. Both would provide a lot of insulation. This would allow the ocean depths to remain comfortably warm, whilst the surface temperature of the ice remains at temperatures <100K. Human settlements could be constructed on or beneath the icy crust. Likely, humans would live in rotating buildings within an otherwise low-g environment. The aquatic ecosystem would provide food and would absorb wastes and waste heat from the human habitats. With gravity being 1000x weaker than Earth, it would also be relatively easy to create open air spaces within the mantle. Bouyant forces wouod be almost negible and the pressure gradient very shallow. Thin walled vessels made from thermo plastics could enclose habitable spaces, which are anchored either to the core or to the ice above.
That inspired me to think of this:
In fact the rings could be expanded out a very great amount. And of course I agree that the habitations in the asteroid proper can be quite good.
If we could adopt from this item which seems to have emerged from the Finns: https://www.sciencealert.com/could-huma … anet-ceres
Image Quote:
So, this thing would have a large amount of Synthetic Gravity devices embedded in it with magnetic bearings.
For Ceres, a ring supporting itself against gravity might be a challenge.
But for smaller objects, perhaps it could be done. In a manner a bit similar to a space elevator, you might have a ring so big that the spin habitats would be on its outer edge, and would be so far from the gravitational center as to weigh very little.
It's a maybe.
A weird thing to think about is that the ring would be sun synchronous, so in a year, it would rotate on it's axis once, so there would be a bit of centrifugal force, against the gravity of the large asteroid, I think.
????
Fun Stuff.
That would be a really big disk.
Done.
Last edited by Void (2023-02-21 11:14:26)
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Relating to the previous two posts, I thought these additional articles were worth a look:
https://phys.org/news/2017-01-ceres-ast … laged.html
JANUARY 20, 2017
Observations of Ceres indicate that asteroids might be camouflaged
by SETI Institute
Image Quote:
https://phys.org/news/2022-05-ceres-solar-migrated.html
Quote:
MAY 19, 2022
Ceres probably formed farther out in the solar system and migrated inward
by Evan Gough, Universe Today
Image Quote:
Image Quote:
https://phys.org/news/2021-08-discovery … -belt.html
Quote:
AUGUST 2, 2021
Discovery of very red bodies in the asteroid belt that resemble trans-Neptunian objects
by ISAS
So, this region has much of the materials needed for a human/technological culture.
So, it does look like the primary path is Mars/Phobos/Deimos, and then out to the asteroid belt, all the way out.
As you have said Calliban, mirrors should work just fine in those regions.
Thanks for starting the discussion.
Done.
Last edited by Void (2023-02-21 13:56:18)
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This is interesting:
Kuiper Belt:
https://www.msn.com/en-us/news/technolo … r-BB1izCDK
https://phys.org/news/2024-02-nasa-hori … uiper.html
Quote:
FEBRUARY 20, 2024
Editors' notes
NASA's New Horizons detects dusty hints of extended Kuiper Belt
by NASA
The Kuiper belt may be larger than thought, or there may be a second Kuiper belt.
Done
Last edited by Void (2024-02-21 11:05:31)
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This is interesting.
https://arxiv.org/pdf/2301.03674
Flourine appears to be present in CI condrites at an abundance of 390 - 420ppm. This is important for far future terraforming of dwarf planets, outer planet moons and oort cloud objects. Flourine can be used to manufacture heavy gases like sulphur hexaflouride, perflourobutane and perflouropentane. The later has a molar mass of 288g/mol. At 250K, mean molecular speed of this gas will be 136m/s. If released onto any body with escape velocity greater than about 700m/s, this gas should remain trapped for geological timescales, i.e. hundreds of millions of years. This gas is also a supergreenhouse gas, trapping IR radiation. This gas is heavy enough to provide a substantial surface pressure on a number of small outer solar system bodies.
Makemake has escape velocity of 910m/s.
https://en.m.wikipedia.org/wiki/Makemake
Titania, 765m/s.
https://en.m.wikipedia.org/wiki/Titania_(moon)
Haumia, 1000m/s at poles, 710m/s at lobes.
https://en.m.wikipedia.org/wiki/Haumea
Sedna, ~700m/s.
If an atmospheric pressure of 0.2bar and surface temperature 250K can be built up, then humans won't need spacesuits to work on the surface. Just an oxygen mask and warm clothing. This would make these bodies a lot more habitable for long term human habitation. But making enough perflouropentane to achieve the task would be a huge challenge.
Last edited by Calliban (2024-05-27 17:00:34)
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That is a very interesting discovery Calliban.
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I think the catch is that Titania has 3.79% of Earth surface gravity. To produce a surface pressure of 0.2bar, we would need 53 tonnes of flourocarbon for every square metre of surface area. Maybe a future humanity that has heavily colonised the entire solar system could do that as a minor project. But to us mere mortals confined to the surface of planet Earth, it looks like an impossibly large job. Then again, building New York city would have looked impossible to a cave man.
A more achievable near term project would be a thin atmosphere of ~1Pa. This would be far too diffuse to allow humans to do away with space suits. But it would screen out micrometeorites and would warm the surface up by perhaps a few tens of Kelvin.
If we deploy these gases on a more massive body like Callisto, then the increased temperature would allow a CO2 atmosphere to form. We do not know enough about the CO2 inventory of Callisto to estimate how high the surface pressure could be. But an atmosphere with column density comparable to Mars, would allow aerobraking, meteorite protection and would filter out the worst heavy primary cosmic radiation. Titania, Makemake and Sedna, have insufficient escape velocity to hold on to a CO2 atmosphere for very long. Only the heaviest of gases could persist on these small worlds. But a very thin atmosphere is better than no atmosphere at all.
Last edited by Calliban (2024-05-28 01:03:38)
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This is interesting. Icy outer solar system bodies like KBOs, appear to be rich in methanol.
https://www.hou.usra.edu/meetings/ices2023/pdf/4005.pdf
They also contain carbon monoxide in abundance, which sounds a little scary.
https://www.ucf.edu/news/scientists-dis … irst-time/
What is the significance? Methanol and CO will react exothermicaly to produce acetic acid.
https://en.m.wikipedia.org/wiki/Acetic_acid#Production
Acetic acid allows plant growth without sunlight. In fact, some fungi and bacteria consume it anaerobically. This suggests that when we eventually colonise the kuiper belt, we can produce food using energy rich chemicals that we mine from the primordial ices. Very little energy would then be needed to produce food. Whilst we cannot live that way indefinitely, it certainly does make setting up a new colony easier.
Last edited by Calliban (2024-05-31 14:58:06)
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That is a good finding Calliban. In the end the true game of reality is to build hydrocarbon biomass and dispose of Oxygen. Too much Oxygen and all the organic matter oxidizes.
Just a little segway:
I think that it is becoming an awareness, that plants do not only provide food to eat to attract animals, but also Oxygen so that animals exist.
Not necessarily by any intention of a mind as we might understand it, but animals will produce droppings, and may also die in proximity of a plant, and so then the plants get nutrition, fertilization. Some plants even capture and kill and digest animals. Without this process nutrients would to a large degree wash into the sea and I suppose, drop to the bottom, perhaps leaving the land and even the seas more barren of plant life.By hosting certain types of birds, I expect a tree gets fertilization. The birds may eat insects and worms, and so then the bird droppings as the sort of gift a tree may like. So, do plants evolve to be attractive to a bringer of fertilizers?
But KBO's and other small worlds. Maybe we could use the phrase "small outer worlds" for many of the Kuiper Belt Objects, Oort Cloud Objects and Rogue Objects.
These objects seem to have three main environments to exist in. The Heliosphere, the Heliopause, and Interstellar Space.
https://en.wikipedia.org/wiki/Heliosphere
Image Quote:
Image Quote:
While in the solar wind, it is still possible to ride the force of it, as a magnetic field will apparently expand as it goes outward. This might allow some type of a mega machine(s) of a ring and field on a trolly. Such might actually generate power. I have speculated on that recently here: https://newmars.com/forums/viewtopic.ph … 59#p223859
In interstellar space there may be Deuterium and Helium 3 to harvest from space. This could make a Rogue Planet attractive. The proper sized planet may have trouble holding Protium, (I believe you call it), but might have a concentration of Deuterium and Helium 3 that it may have collected over time. So, it may be that Rogue Planets could "breathe" a concentrate like that, practically forever.
This could also be true on a periodic basis for some outer worlds beyond the solar wind. They may wander in an out of the solar wind as it appears in the images above.
I also think that these objects may gain more radioactive materials over time than worlds inside of the solar wind.
https://phys.org/news/2023-02-radioacti … to%20Earth. Quote:
Using sophisticated computer modeling of the elements' journey through space, scientists have now found that the heavy elements produced in collisions of neutron stars can "surf" on blast waves of other supernovae across our galaxy and down to Earth.
I think that a world which may have a sea, may have a way to get that stuff into that sea. Maybe tectonic plates in the ice?
This could explain the possibility of such on Eris and MakeMake? https://www.astronomy.com/science/dista … telescope/
Quote:
At the very least, this indicates an icy boundary hitting a rocky core. That rocky core could have localized hot spots that keep an oceanic layer warm enough to transport methane and other chemicals to the surface via geysers. Convection in the core could also create a shallower ocean that still manages to expel chemicals to the surface. A third possibility is that convection drives up the methane through the ices without necessarily passing through an oceanic layer. (It may also be, as the paper mentions, that two different mechanisms are at work simultaneously on either world.)
The methane is unlikely to have a biological source, the paper says, although the presence of an ocean means that life could be there.
And then I am very interested in the Heliopause. Do materials expelled from the sun, and bumping the interstellar medium, accumulate there and even accrete to objects in that location? Do heavy elements accumulate there from interstellar high energy episodes?
If we believe in the big bang, then at first there was little or none of heavy materials like Uranium. But it seems that the stars keep forming with more and more metals. So, radioactivity may be a path that Rogue and outer world may take to become life giving.
This may be a thing that will increase for some billions of years until large stars are no more made, and Neutron Stars do not collide very often.
I am not sure that I believe in the theory of the Universe quite as it is now given. I have wondered if by some method matter may emerge from virtual particles, if energy is provided in some way. But of course, that is only a notion and not quite an idea yet.
We are told that the Universe expands at variable rates. This suggests to me that more of what matter is embedded in is being created. Space-Time? Some substructural things of sorts then. Is it impossible that a white hole is occurring at a low rate where matter is not situated? But I would not invest my money in the idea, I would just follow its trend if there is one.
But there could be more out there than we have previously supposed is out there.
Done
Also wanted to remention the notion of natural saltwater fission reactors. Salts react to environmental situations and may concentrate in solutions, perhaps types of salts. On Eris for instance freeze thaw cycles might produce solutions with more or less concentration of Uranium. Perhaps at times and places, it becomes enough to produce some significant heat, more than the normal rate of decay.
Done
Last edited by Void (2024-05-31 22:44:18)
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I should correct the above as I expect that most Hydrogen of any sort will be inside of molecules.
A Steppenwolf world is said to be Mars size or larger, (Up to some limit, I expect), and would permit open water oceans. But that may not be ideal from a human point of view, as the air pressure would be extremely high.
A pressure from 1/4 to 10 bars might be somewhat suitable to humans on the surface. However, that level of pressure is not expected to warm the world that much.
The use of nuclear flash bombs might thin an atmosphere down to levels suitable to human activity or that of robots which could be more tolerant of pressure.
Or perhaps a laser might be used to thin the atmosphere.
Done
Perhaps someday we might encounter an alien type that can exist on Steppenwolf Planets and perhaps Breath Hydrogen at high pressure, and then perhaps drink a water/Hydrogen Peroxide solution. Or perhaps someday we will invent one.
Such aliens might do rather well at the bottom of an ocean of water as well. (Just to mess with people's minds). Make a SciFi about that. Sightings on Earth suggest craft that do dive in the ocean, and it is proposed that we have aliens at the bottom of the ocean. Now that would be a story.
Done
Last edited by Void (2024-06-01 10:24:38)
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A Mars sized world would be ideal, as it is large enough for open-sky teraforming. We don't need to laser ablate the atmosphere. Simply heating an atmosphere that deep on a world with Mars gravity, will result in atmospheric escape. This is especially true if the atmosphere is molecular hydrogen. We would need a very powerful fusion reactor to do this. But by the time humanity has spread that far out into space, we should have the ability to produce huge structures.
But looking at the TNO population, I think most of the attached and ubattached bodies we find are going to be in the 100 - 500km diameter range.
https://en.m.wikipedia.org/wiki/List_of … an_objects
Such worlds could be almost as useful to us. A 500km TNO has surface gravity about 1.3% of Earth, assuming a 50/50 rock and ice composition. This is much too small for classical teraforming, as only the heaviest of gases could form a stable atmosphere. But the body is a huge thermal mass that can be useful to us in establishing a habitat colony. Why build a human colony on a TNO rather than in open space? There is a simple but very impirtant advantage than an icy world provides as a human habitat. It is a heat sink. Human habitats will generate a lot of waste heat that must be dumped into space. The required radiators will be huge. If you try and pack too many humans in too small a volume, eventually the required radiator ends up dwarfing the habitat. If we build a habitat on a natural body, we can dump heat into it and use it as a natural radiator, avoiding the need for a radiator alogether.
A habitat within the icy surface of such a world, could be constructed volumetrically. Imagine an O'Neill cyclinder that is divided into decks. The amount of land you can fit within a km wide pressure vessel will be immense. We can do this on a TNO, by using the cold body as a heat sink. As it melts, this becomes even easier, as we can pump its water through heat exchangers. That makes the building of huge and densely populated habitats relatively cheap. So we save money by building on a natural icy body.
Ultimately, the entire world will melt, with an icy crust covering a deep water mantle and a rocky core extending to 50% of radius. We would give this icy world a microbar atmosphere to maintain a vapour pressure over the ice and suppress evaporation into space. The thin atmosphere would cool the planet, with warm gas molecules rising and then sinking again as they lose heat to radiation. A dense gas like SF6 or C5F12 would work best. We only need a microbar surface pressure. Our habitats would float on the ocean within the ice shell. They would be tethered together by long cables running over the surface of the ice and through the water. Trains would run through tubes on the surface ice, connecting the habitats in a global network. They would form a hexagonal grid across the surface.
At -70°C, the vapour pressure of ice 0.2Pa, which is 2 microbar. At this temperature, each square metre of ice will radiate 97W of heat into space. A 500km diameter body will therefore radiate some 76.2TW of heat into space. Present human society uses energy at a rate of 19.63TW. This suggests that a mid-sized 500km diameter TNO could ultimately support a society as large as present human population, even if per capita energy use increased considerably. It would take 20,000 years just to melt the ice. So in the short term, human population couid be even greater. But eventually it would need to decline to a level that would keep energy use within the thermal capabilities of the ice shell.
Last edited by Calliban (2024-06-02 08:38:48)
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That is a good set of notions Calliban.
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Isaac Arthur discusses the use of planets as space ships.
https://m.youtube.com/watch?v=oim7VvUURd8
This is very similar to the idea of using KBOs as space ships, by propelling them to solar escape velocity. It suffers the same problem unfortunately. The energy needed to do it is just insane.
A 100km diameter KBO has mass about 500 trillion tonnes. Solar escape velocity at Pluto distance from the sun is about 2.3km/s. Accelerating this body to solar escape velocity means imparting a kinetic energy of 1.4E24 joules, or 43,885 TW-years. In other words, the power presently consumed by humanity over 2300 years. It is not impossible. But it would seem to be extremely difficult. Accelerating anything larger, the energy requirements scale with radius cubed. So a 500km body would need 125x as much energy to escape.
Escape velocity declines in proportion to (1/d)^0.5, where d is distance from the sun. For something 1000AU from the sun, i.e in the Hill's cloud, some 25x the distance of Pluto, solar escape velocity would be 460m/s. At this distance, it would take 25x less energy to escape from the sun. The key then to using natural bodies as slow interstellar space ships, is to find one that is only weakly attached to the sun or in the case of a rogue object, entirely unbound. At 20,000AU, which appears to be the origin of most long period comets, solar escape velocity is reduced to about 100m/s. A 100km diameter body would there need 87TW-yrs of energy to escape.
That begins to look far more achievable. The heat limit for a civilisation living on such a body woukd be 3TW. So if 10% of that energy is devoted to propulsion, the body would reach escape velocity in 290 years. Not bad at all, given the aeons it will take to cross interstellar space. The heat limit for any body scales with surface area, but the mass scales with volume. So it would take 5x as long to accelerate a 500km body to escape. But that is still only 1,450 years. At Pluto distance from the sun it woukd take 73,000 years, which begins to look absurd.
Where could we take these slow-boat world ships? Here is a list of stellar close approaches, past and present, to the sun.
https://en.m.wikipedia.org/wiki/List_of … encounters
In 84,590 years, one star LSPM J2146+3813, will pass within 1.8557 light-years of the sun. How fast would our world need to travel to catch it? 1ly = 9.46E12km. So the required velocity would be:
V = (1.8557/84,590) x 300,000 = 6.58km/s.
That seems like a stretch, but it could be doable. The energy requirements to accelerate a 100km body to this dV are 359,184TW-yrs. Lets say it take 10,000 years to accelerate. The power requirements are 36TW. That is almost twice the power consumption of humanity. A serious stretch.
In 1,017,000 years, the star 2MASS J1151-0313 will pass within 1.98ly of the sun. To catch that star, our world must be travelling at 0.585m/s, implying an energy requirement of 2830 TW-yrs. If acceleration lasts 10,000 years, that is a power requirement of 0.28TW. That is more achievable and well within a 3TW heat limit.
But we are talking about a journey time of over 1 million years. That's a lot longer than humans have been around and 100x greater than recorded human history. Could we build a civilisation that lasts that long? It is certainly something to think about. I guess when we talk about colonising different places, we don't have an end date in mind. We talk about starting to colonise Mars in 20 years, say. But we don't give much thought to when humans will be gone from Mars. The assumption is that we stay forever. Maybe the same thinking applies to colonising other places, like KBOs turned into space ships. On that line of thought, 1 million years is only 0.02% the age of the solar system. It isn't unreasonable to think humans will still be around in another. It is more a question as to whether they can keep their shit together on a far away world that long. I think the key thing is, provided they don't lose their technology and have what they need to live happily on their little world, there is no reason to suppose they won't exist until their fuel runs out.
How long would that be? The energy content of Earth seawater, if all deuterium is fused, is 3GJ/litre. De concentration is KBO water is about the same.
http://large.stanford.edu/courses/2023/ … rzybocki2/
If we assume that half the mass of our KBO is water, then the total deuterium energy content is 24.9million TW-years. That is enough to generate power at the heat limit for 8 million years. So our world has easily enough fuel for a 1.017MY journey.
Gliese 710 is expected to pass within 0.167ly in 1.296MY. To catch that star, our travelling world needs to reach a velocity of 37m/s. That is easy. We might even use a 500km KBO to do that mission. But again, 1.3 million years is one heck of a journey time. The star is currently 62.248ly away from us. So its relative velocity is 14.4km/s. Our future humans could leave their icy home and use nuclear thermal or fission-fusion pulse rockets to match velocity with it.
When I get time, I might put together a spreadsheet calculating the velocity requirements to rendezvous with each of the stars predicted to make close approaches to the sun in the future. We can evaluate each one as a potential target.
Last edited by Calliban (2024-06-02 17:28:25)
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Of course this is just for fun. I have wondered what would happen if Venus got kicked out of the solar system to become a rogue planet.
Let's say that it was a Venus like planet around another star, and someone thought that making it rogue would be a good thing. If we presume cloud cities, and orbital cities, then interesting things might happen.
The planet would gradually cool from a lack of sunshine, but it would have a lot of thermal inertia. There would be a lot of wind power for some time. As it became cooler, then you would have a lot of geothermal power for a very long time.
Over time in interstellar space, it would likely accumulate Hydrogen and Helium, some of it being fusion fuels.
In time the CO2 Oceans might convert to water oceans from the Hydrogen input.
So, if you had that you would have something like a Bussard Ramjet but using gravity to collect fuels and propulsion mass from the interstellar "VOID!".
So, this occurs to me to be an interesting thing that might be done with superhot planets around other stars. If you are in the solar wind, you are not going to get much in the way of fusion fuels, but in interstellar space you could have a continuing infall of fusion fuels, and eve fission fuels.
One thing you could do is travel to a Stellar Nursery, and perhaps even slow down by a vast magnetic field???
Then you might be in on the ground floor of the birthplace of stars. But you would need to have a way to deal with big ones that may explode. But it is the big ones that are the most valuable in the short term, according to Isaac Arthur: https://isaacarthur.net/video/colonizing-giant-stars/
I am suspicious that stellar nurseries may capture rogue planets and smaller objects, and these may be seeds for future accretions that will make stars and planets.
Isaac Arthur also talks about Star Lifting, which could allow a giant star to have an extended life span.
Food for the imagination.
Done
https://www.space.com/orion-nebula
Only quote:
approximately 1,350 light-years away
So, then if multiple worlds were terraformed/inhabited, then as the cluster disassembled humans would be distributed through the galaxy.
Done
Last edited by Void (2024-06-02 19:03:16)
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Altered title to include "and Rogue Planets".
This is the reason: https://www.msn.com/en-us/news/technolo … 1fa9e&ei=4
Quote:
Planet-forming disk around small star offers big surprises
Story by Will Dunham • 5d • 3 min read
Quote:
Webb's observations showed that the gas in this star's protoplanetary disk - ingredients for future planets - is carbon-rich with no evidence of water vapor, as opposed to the oxygen-rich gas and abundant water vapor in such disks around newborn sun-like stars.
So, I am wondering about rogue planets from Red Dwarfs, and maybe Brown Dwarfs.
My thinking is that these small stars may make lots of terrestrial sized worlds, rather than Super Earths, Mini-Neptunes, and ice and gas Giants. While they may be short of water if ejected from a star, then they may collect a Hydrogen atmosphere and may generate more water if volcanism is present on the planet.
But I don't know the frequency at which Red and Brown Dwarfs may eject terrestrial sized planets.
I expect that binary star systems may be better at ejecting planets than are singular stars.
If so, the hope would be that there would be a lot of Steppenwolf planets, and perhaps even some of these may pass through our Oort Cloud or maybe even spend time in it, maybe even be captured.
An article about Steppenwolf Planets: https://astrobites.org/2011/02/08/life- … lar-space/
My current understanding is that a planet the size of Mars or larger could be such a planet. Red Dwarfs may make a lot of them, and if they are ejected then they may be an interstellar resource.
I would not be so needing them to be warm enough for liquid water as to have nuclear fission fuels in an atmosphere.
It is possible that humans and their machines might be able to planet hop in the future using these worlds, if they exist in abundance.
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Last edited by Void (2024-06-11 21:46:02)
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Here is another article about low mass Star formation and the planets they may have form with them: https://www.msn.com/en-us/news/technolo … 5b95d&ei=4
Quote:
"Many primary atmospheres of those planets will probably be dominated by hydrocarbon compounds and not so much by oxygen-rich gases such as water and carbon dioxide," Thomas Henning, MINDS team leader and a researcher at the Max Planck Institute for Astronomy (MPIA), pointed out in the statement. "We showed in an earlier study that the transport of carbon-rich gas into the zone where terrestrial planets usually form happens faster and is more efficient in those disks than the ones of more massive stars."
My hope is that the Oort Cloud and perhaps even the Kuiper Belt could have captured terrestrial sized planets when in a multiple star forming nursery.
So, it might be possible to have captured terrestrials in the very outer solar system, that come from red dwarf stars.
If beyond the solar wind, then they may have accumulated Hydrogen and Helium atmospheres, which would help to mask their existence maybe.
We really can't see that far out anyway, not very well, not yet.
Done.
Tar Volcano's? Such might foster life. Life in Tar: https://www.sciencedaily.com/releases/2 … 151916.htm
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Last edited by Void (2024-06-12 11:22:16)
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https://www.youtube.com/watch?v=01-t06fWGeI
Quote:
Evidence That Pluto and Triton Are Actually Long Lost Siblings
Anton Petrov
1.33M subscribers
So, maybe a type of world, where more of that type may exist in the Kuiper Belt.
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Last edited by Void (2024-06-26 10:02:53)
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This is of some interest, Lagrange points that would be between our solar system and the center of the galaxy.
https://www.youtube.com/watch?v=gM98Wki7BLo
Quote:
Model Suggests Unusual Gravitational Point 3.81 Light Years From Earth
Anton Petrov
1.34M subscribers
There are some concerns that we should see some visible objects, so this is not guaranteed, but something to ponder, investigate.
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Last edited by Void (2024-08-04 09:40:08)
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Flourocarbons are some of the heaviest gases, with high global warming potential. Flourohexane has a low boiling point of 52°C and a molar mass of 0.338kg/mol.
https://en.m.wikipedia.org/wiki/Perfluorohexane
At 250K, these heavy gas molecules would have a mean speed of 125m/s.
https://www.calctown.com/calculators/ma … ular-speed
This suggests that any moon or dwarf planet in the outer solar system with an escape velocity greater than about 500m/s, could support a microbar atmosphere with a half life measured in centuries. Bodies with escape velocity greater than 700m/s, should retain this gas indefinitely.
Under low gravity conditions, a microbar atmosphere may be sufficiently dense to suspend nanoparticle rods as dust within the atmosphere.
https://www.space.com/mars-terraforming … oparticles
This could be used to warm the surfaces of moons and dwarf planets considerably, especially if ground based fusion reactors were adding heat to the surface.
Atmospheric retention would then be improved by a strong negative thermal gradient with increasing height. At low altitudes, atmospheric density would be sufficient to elevate nanorods keeping the atmosphere warm. At higher altitudes above the nanorod layer, the atmosphere would cool rapidly reaching temperatures of 20 - 50K, depending upon distance from the sun. At this temperature, mean speed is just a few tens of m/s and the the gas is likely to condense into solid particles falling back into the atmosphere and revaporising at lower altitudes.
Thin atmospheres supporting nanorods provide a way of keeping cold outer solar system bodies warm. Such bodies could support watery surfaces under a thin layer of ice. Water vapour would condense as it ascends into the cold atmosphere and fall back as snow.
Last edited by Calliban (2024-08-12 13:46:30)
"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."
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Well, that then is a good idea, and also what about worlds like Titan and Venus?
In each case we would need to be certain that life is not an issue. For Venus that should seem easy.
While Venus is "Off Topic" still if it is lifeless, an expanded atmosphere would be easier to extract materials from at higher altitudes.
My previous post before yours mentions the potential for Rogue worlds locket to our solar system. In those cases, some nuclear power source seems like it would be needed, but maybe the particles would make it easier to warm an atmosphere with Hydrogen and Helium on its top layers and perhaps Nitrogen under that.
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In terraforming Venus, we need a way of blocking sunlight out. If we bombard the upper atmosphere with fine dust, say lunar regolith dust, it will block out the sun.
Titan is a special case. The nanodust layer must be located above the hydrocarbon haze to be effective. Depending upon what temperature we want to heat the atmosphere to, we could make use of hydrocarbons or water ice to make the nanorods.
"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."
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While I value your analysis and do not dispute it as valid to an intention, it is now thought that Titan may have sand dunes of comet dust at it equator. So, that could be alternate materials.
For Venus, one scheme to terraform it would be to hit it with a comet to heat it up and swell the atmosphere, to make the atmosphere be lost to space. I would consider swelling the atmosphere, using thermal terraform methods such as the rods and greenhouse gasses. But then contrary to allowing the solar wind to strip the atmosphere, perhaps protect it with an artificial magnetic field. Then to capture the gasses into artificial habitats. Aerobraking terrestrial crossing asteroid materials into the expanded atmosphere.
But this would first require that no life is in the clouds.
It is possible that Venus has an underground ocean of water that replenishes its hydrogen, so then Hydrogen would be available from that, or captured from the solar wind, or transported in from outer solar system water sources.
And yes, perhaps someday a method to move some of that atmosphere to other worlds could perhaps come into existence. Mars and perhaps our Moon come to mind.
As I can see it orbital energy is altitude above a gravity field, and inertia of a mass. So expanded atmosphere may be easier to capture into an orbit and then move to another location. Clark tech, of course, but there is a glimmer of hope on this one.
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Last edited by Void (2024-08-13 08:34:45)
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