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For Calliban re vacation in the Netherlands!
Thank you for telling us of your plans, and best wishes for a safe and enjoyable trip!
Your observations of the Dutch people, and your assessment of the example they provide for resilience in the face of challenges will be welcome additions to the forum archive.
Adam Smith included the Dutch in his evaluation of economic systems in use in Europe of his time.
It is possible the forum membership includes a citizen from the Netherlands (or two) but the User List feature of our forum software does not include a lookup by location. The gent I remembered is from Belgium. Close, but no cigar.
***
This next part of this post is to request a consultation.... I am attempting to create an animation that will show how the Rotating Toss idea you and Terraformer have been discussing would work.
Because you are skeptical about artificial intelligence, I will remind you (and anyone who happens to read this post) that research shows that the benefit of artificial intelligence is inversely related to the capability of the user. In your case, you would get no benefit at all. However, because I am in the minor leagues, I am getting a great boost.
My question for you is: As I attempt to design animation to show how the Rotating Toss would work, I need to have enough understanding to be able to instruct the software to correctly configure the physics engine.
Let us assume we are standing on the surface of our rotating asteroid or dwarf planet. We have a spring loaded accelerator on hand, and we have positioned a package of valuable minerals on the launcher. We have a strong but light line attached to the payload, and the near end of the line is secured to a strong anchor in the regolith.
My expectation is that if I launch the payload with the spring launcher, the payload will ascend vertically from the surface while trailing the line. The payload will have two motions. It will have motion outward along a radial line from the center of the object, and it will have angular momentum equal to the angular momentum of the surface of the object at the launch site.
As I understand your vision of the Rotating Toss concept, the payload needs to cross a point where the gravity of the asteroid is less than the centripetal force that would be felt by the payload when it reaches the end of the line.
Question 1: What would be suitable term to describe the point of balance between gravity and centripetal force?
Question 2: How can we determine the optimum length of the line for a particular toss?
As a quick update regarding animation: The Python program ChatGPT4o made for me yesterday is working, but it needs a lot of fine tuning before it accurately reflects the Real Universe. In it's unfinished but working state, the payload reaches the end of the line, and then rebounds due to elasticity of the line. It rebounds to the surface of the asteroid, but since the objects are all defined (by default) as perfectly elastic, the payload bounces away and the tether assumes a writhing snake aspect before the payload bounces on the opposite side of the anchor.
My current thinking is to convert the animation so it can be served from a web site. in the mean time, if you happen to see this and can provide some guidance I'd appreciate it.
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For Calliban re tapping rotational energy of a space object....
I'm wondering if "launch point" might work as a term for the scenario we are discussing.
It's a bit vague, and you may be able to suggest something better. What I'm looking for is the point above the surface of a space object where the pull of centripetal force is greater than the pull of gravity on a mass at that distance.
I'll put a transcript of a discussion of this question in another topic for the record.
There is (probably) no need for you to bother with it.
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For Calliban re NextBigFuture link with Brian Wang story...
Thanks for the link, which had a lot of images to help explain the concept.
The comments section seemed to be leaning toward skepticism.
No one there mentioned the issue you raised, but the discussion of muons participating in the process seemed plausible
A detail left to be solved later is how the fluid circulating in the blanket would be processed to extract useful atoms.
The 79Kr is extracted and enriched.
Whatever that method is, it would have wide application.
The ability to rapidly and efficiently sort atoms would be useful for desalination or water cleaning as just one example of many.
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I don't think muons can be produced by positron annihilation, unless those positrons are accelerated to very high energy. The rest mass of a positron or electron is 0.511MeV. So an electron-positron annihilation even will yield 1.022MeV in gamma rays. By contrast, the rest mass of a muon is 106MeV and the pion that decays into the muon has mass of 140MeV. So annihilation energy of an electron-positron collision is too small by about two orders of magnitude.
The positron dynamics idea appears to be to use positrons to bombard deuterium gas with highly focused gamma rays. That will succeed in generating some fusion events. The question is will it produce enough fusion events to make the process self-sustaining? I don't know and I have no way of modelling the process. But I can see potential problems with the idea. One problem is that most of the gamma energy will be absorbed by electrons. Some will be re-emitted as bremsstrahlung x-rays, which could still have sufficient energy to drive fusion. Ions that absorb gamma rays will possess enough energy for fusion. But they will also tend to lose energy interacting with electron shells.
One way of enhancing the fusion rate would be to use lattice confinement, as demonstrated by NASA. But that introduces the problem that the lattice atoms will also scatter gamma rays. The chain of events that needs to occur to make this work, is for one positron annihilation to generate more than 1 fusion event. Most fusion reactions generate neutrons, which can then be absorbed with 78Kr blanket to produce 79mKr. But there are losses at every stage of the process. So the question becomes, will fusion rate be sufficient to make up for those losses? I suspect that this question can only be answered by experimentation.
Last edited by Calliban (2025-02-28 10:29:00)
"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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For Calligan ... re #204 ... thanks for engaging with me on this interesting idea...
One of the comments after Brian Wang's article caught my eye.
Based on your assessment of energies in #204, I'm wondering if "DrPat" is missing something important?
doctorpat
November 25, 2018 at 9:40 am
They say “positron catalysis of fusion” but what does that actually mean? From an earlier article on NBF positron emission: ²²Na → ²²Ne + 1 e⁺ + 0.94 MeV of kinetic energy positron annihilation: e⁺ + matter → pion (5%) or kaon (95%) kaon decay: kaon → muon (80%) in 20 nsec muon capture: muon + D or T → mD or mT fusion (1): mD + T → ⁴He + ¹n + muon (non-consumed) (0.01 – 0.1 nsec) fusion (2): mT + D → ⁴He + ¹n + muon (non-consumed) (0.01 – 0.1 nsec) fusion (3): mD + D → ³He + ¹n + muon (non-consumed) (0.07 – 1.5 nsec) muon decay: muon + time → electron + neutrinos (2,200 nsec) So there you have it. Positrons react to form kaons or pions. They decay to form muons. Actual muons are involved in the fusion reactions.
The comment does not reveal the original source of the sequence quoted.
Update: I asked Google about NDF and it came back with a Wikipedia citation on a class of drugs:
https://en.wikipedia.org/wiki/25I-NBF
I asked again and this time got a hint that the B may stand for benzyl ...
Cayman Chemical
https://www.caymanchem.com › product › 25i-nbf-(hy...
25I-NBF is an N-benzyl derivative of the phenethylamine hallucinogen 2C-I which acts as a highly potent partial agonist for the 5-HT2A receptor.
Nasty stuff, apparently.
I tried a third time and ** this ** time the pieces seem to fit together:
Search Labs | AI Overview
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The radiolabeled form of the compound 25I-NBF has been used in positron emission tomography (PET) to map the distribution of 5-HT2A receptors in the brain.
Explanation
Positron emission is a rare type of nuclear decay that occurs when a nucleus emits a positron, a type of beta particle. This process changes an atom of one chemical element into an atom of another element with a lower atomic number.
25I-NBF
25I-NBF is a derivative of the hallucinogen 2C-I. It's a potent partial agonist for the human 5-HT2A receptor. The radiolabeled form of 25I-NBF has been used in PET scans to map the distribution of 5-HT2A receptors in the brain.
Positron emission in nature
Positron emission occurs extremely rarely in nature on Earth. Known instances include cosmic ray interactions and the decay of certain isotopes, such as potassium-40.
Update later ... if someone has plenty of time and patience, the discussion of the process of merger of a positron and an electron may be of interest.
The discussions in StackExchange start with Newtonian physics and transition to Quantum mechanics. This might be worth a topic in the Science category.
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A positron is positively charged. So is a nucleus. Positrons have a +1 charge and very small mass - on the order of 1E-3× the mass of a proton. Unless they are accelerated to really insane energy, they don't have enough momentum to get close to a nucleus. So positron capture doesn't really work. Gamma rays can scallate a nucleus. But the required energy is tens of MeV for photo-fission of heavy actinides. Even more for lower Z elements, as binding energy increases. So positrons won't do that either. The ion energy needed to initiate D-T fusion, is on the order of 4KeV. A pair of 511KeV gamma rays, contain enough energy to catalyse over 200 fusion events. If more than about 1% of gamma energy causes fusion, then the engine could produce enough 79Kr to be self-sustaining.
"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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For Calliban re #206
Thanks (again) for continuing this exchange!
A pair of 511KeV gamma rays, contain enough energy to catalyse over 200 fusion
Where might such a pair of gamma rays come from?
It seems that when a positron and an electron merge, gamma rays are produced, but I have lost track of the amount of energy released.
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For Calliban re http://newmars.com/forums/viewtopic.php … 85#p230085
Thanks for the link to that interesting paper on collider research! It provides a glimpse of what life in that level of research environment is like!
Earlier I had inquired about the 0.511 MeV gamma rays ... today I asked Google and was reminded that that is the output of a e+ e- annihilation.
The 79Kr is extracted and enriched.
How this isotope is separated from the 78Kr in the sleeve around the chamber is undefined, and it is in fact a capability that could be useful for a wide variety of other applications. The separation needs to be highly efficient and fast ...
Per Google:
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The half-life of Krypton-79 (79Kr) is approximately 1.455 days.
Explanation: According to most isotope data tables, 79Kr has a half-life of 1.455 days.
Key points about 79Kr:
Half-life: 1.455 days
Atomic number: 36
Decay mode: Electron capture
I asked Google for the decay product of 79 Kr...
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The decay product of Krypton-79 (79Kr) is Bromine-79 (79Br); it decays through positron emission, meaning the atomic number decreases by one, resulting in bromine as the daughter nucleus.
Key points about 79Kr decay:
Decay mode: Positron emission
Daughter nucleus: Bromine-79 (79Br)
So I deduce that 78 Kr is consumed in this process, and thus the ship's tanks must be filled with enough to complete the mission.
I asked Google for the abundance of 78 Kr on Earth:
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The abundance of Krypton-78 (78Kr) on Earth is approximately 0.35%.
Explanation:
Isotopic abundance:
This means that out of all the naturally occurring Krypton atoms on Earth, about 0.35% of them are Krypton-78.
Source:
This information can be found on the periodic table, where the isotopic abundance of Krypton-78 is typically listed as 0.35%.
Per Google, Krypton is present in the atmosphere of Earth at the rate of 1 part per 1000000 by volume.
There are numerous isotopes of Krypton. 78 Kr is shown as radioactive, and 85 Kr is reported radioactive elsewhere.
Krypton can be obtained by fractional distillation of liquid air. But the captured atoms will be of all isotopes.
I am dubious of the practicality of isolation of 78 Kr in sufficient quantities to support a deep space mission of any significant duration.
The history of the discovery of Krypton in 1898 is interesting.
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for Calliban re trip to the Netherlands...
The Google Meeting today included discussion of your planned trip to the Netherlands. That was a fun part of the meeting, including history of the building of the dikes and various failures that have occurred. There is interest in a bit more detail of how you'll be making the trip. Flying is certainly possible, but surface transportation in Europe is SO much better than in the US, you might be considering that.
Your observation about the experience of reclaiming land from the sea and similarity of claiming living space on Mars is certainly of interest as well. The stress on Hollanders is not quite as severe as will be the case on Mars, but there is no doubt that there is a life and death worry present in the minds of all those who live below the level of the sea, even if that worry is buried out of the conscious mind.
In any case, the group wishes you and your traveling companions a safe and enjoyable trip.
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Calliban:
I was going to ask how you intend to get from England to the Netherlands, but Tahanson43206 beat me to it. The trains go through the Chunnel, and all over Europe. I'd suggest those trains.
GW
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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Calliban:
I was going to ask how you intend to get from England to the Netherlands, but Tahanson43206 beat me to it. The trains go through the Chunnel, and all over Europe. I'd suggest those trains.
GW
We are flying from Glasgow to Schipol. The Eurostar would be good if we were travelling from SE England. But from here up north, it would mean a whole day on the train each way.
"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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For Calliban re link to Wikipedia article on ZETA
The article you suggested was most recently edited by:
Last edited 3 months ago by Mandsford
This article contains history from the 1950's and includes the interactions between the UK, the US and the Soviet Union. Of particular note is the Cold War fears, and the eventual decision to de-classify fusion research.
The history of ZETA is worthy of note. The embarrassment experienced by the UK team was due to inadequacy of the measurement apparatus available at the time. Introduction of the use of a laser to measure plasma temperatures gave all teams (UK, US and Soviet) much better readings on the actual performance of the various designs.
The editors of the article seem to me to have taken great care to capture the nuances of the interactions of personalities engaged in this important work over decades.
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For Calliban re video: Whole ecovillage fits inside giant greenhouse...
Thanks for this introduction to a group of RobertDyck's countryfolk!
A ** lot ** of thought and hard work went into that project!
It's a bit of a challenge to try to translate the Canadian environment to Mars.
Any habitat on Mars will be a pressure vessel.
Half a bar is RobertDyck's recommended pressure for Mars.
That may be acceptable for enclosed spaces with windows in frames.
It would be interesting to learn of examples of glass walls/windows that hold pressure on Earth.
Examples that come to mind are underwater living space that exist in a few locations on Earth.
In that case the pressure is on the outside trying to burst into the living space.
In comparison, the Mars situation may be less stressful on the windows and frame.
The basement space seem to me a closer match to what might be developed on Mars.
The community workshop seems an essential component of the collection, along with storage spaces separate from apartments.
The exercise space would be essential as well.
An element that is needed on Mars is the equipment needed to maintain pressure, while supplying oxygen and removing carbon dioxide and other molecules not needed in the space. That equipment would be a constant source of noise, so I assume it would be physically separated from the living spaces.
Submarines on Earth would presumably be valuable examples to study when designing habitats for Mars.
The video closed with a visit with a resident.
I note that artificial lighting is present throughout the facility, and air management is going on without being obvious.
Plumbing is quietly ubiquitous, as will surely be the case in the Mars version.
A gifted architect (and probably a team) were involved in creating that complex.
Update: The cupola on the ISS is a good example of what a window structure on Mars might look like.
It might turn out that an entire roof could be constructed of these sturdy devices, assembled in a frame of cast iron.
Cast iron is a building material you (Calliban) have recommended in the past.
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For Calliban re paper on reduction of iron oxide using hydrogen under pressure...
http://newmars.com/forums/viewtopic.php … 06#p230406
What a superbly well written paper!
Do you have a sense of the optimum batch size?
Can a batch be processed in one Sol's daylight?
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TH, I couldn't say at present. The bins will need to be handled by crane, but this is unlikely to be a limiting factor for batch size. The size of the batch will be limited by the volume of the pressure vessel. If PVs are made from alloy steel, the wall thickness will increase as enclosed volume increases. Beyond a certain point, it becomes very difficult to weld. We could use concrete pressure vessels with steel stress carrying tendons. It is possible to build much larger vessels in this way. Pre-stressed cast iron vessels can take higher pressure, as crush strength of iron is much greater than that of concrete. The higher the pressure, the more rapidly the iron oxide will reduce into pure iron.
In chemistry, reaction rate is proportional to reactant concentration, which at constant temperature scales linearly with pressure. Double the pressure and reaction rate doubles. Reaction rate will be governed by the Arhenius equation. This states that reaction rate increases exponentially with temperature: R = e^kT.
Last edited by Calliban (2025-03-18 17:49:29)
"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."
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For Calliban re #215
Thanks for considering my observation about the paper, and my questions about how this might work on Mars.
I was ** really ** impressed by the quality of the paper you showed us. The work was of high quality (as nearly as I can judge) but what I ** really ** liked was the quality of the writing as rendered in English, although the work was apparently done in Germany.
It is possible you may not have had time to read the entire paper. The researchers appear to have found that that higher pressure and lower temperature seem to provide a sweet spot in terms of the quality of the nanoparticles produced by the process.
My guess is that a solar power collection system on Mars is going to be challenged to deliver the needed power to a large facility.
It is for that reason I am imagining a small batch might turn out to be more practical for Mars. The work has to be performed in the day time, but the system could be loaded ahead of sunrise, and if your prediction that compression would produce the needed temperature, then the batch could run all Sol and the product could be unloaded at night.
If you have time, please see if my reading of the paper is right, that there is an optimum combination of temperature and pressure to deliver the best/most desirable nano particles.
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TH, I am so used to papers being behind paywalls, that I hadn't noticed that this one could be downloaded! I will read it this evening and comment some more.
One property that would be useful in this application is the low thermal conductivity of highly porous metal oxide powders. Once heat is input into a large pile of Fe2O3 powder, it would take many hours for temperatures in central regions to drop out of the reaction zone. We could line the interior of the vessel with a refractory powder to increase this effect even more. So it may be that we can fill the vessel with iron oxide, pressurised it with hydrogen during the day and let it cook overnight.
I agree that smaller vessels will be easier to make than larger ones. We do have vessels that can sustain pressures of 500MPa. But the larger the vessel becomes, the more challenging its construction becomes.
It is worth noting that this technology, if it proves to be practicable, would produce a crude iron powder. To produce useful steel, we must melt the powder in an electric arc furnace and burn off impurities with an oxygen lance. But everything starts with crude iron. Most western countries import crude iron from other producers and convert it into steel in electric arc furnaces.
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For Calliban re #217
I dropped off an overview of the composition of the surface and crust of Mars, in one of Void's topics:
https://newmars.com/forums/viewtopic.ph … 19#p230419
When you get a chance to study the paper you linked for us, you'll find that the research team used highly refined ingredients for their scientific experiments. I bring this up because the input to any process on Mars would start with what is actually there.
The surface material found on Mars can be placed in a bin, as you have described, and treated with hot hydrogen under pressure.
I wonder how useful that procedure would be?
The gases released must be captured on Mars because they are all valuable.
The solids left behind would be ? what ?
***
I like your idea of heating the retort with solar energy during day, and letting the retort bake overnight.
The practitioners would quickly learn the best combination of ingredients and time to achieve desirable results.
Since every atom on Mars is valuable, there would be significant additional processing needed after the bin is removed from the retort.
Please put your reply in one of the iron topics. We have a great number of topics containing the word iron.
I'm wondering if we need a topic about processing of iron on Mars.
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This link provides data on the average composition of Martian soils.
https://ntrs.nasa.gov/api/citations/201 … 005414.pdf
The alkali and alkali earth oxides will not react with hydrogen. Not sure about the manganese and chromium oxides. The crude iron that is produced will need to be melted and treated using the basic oxygen process, which will burn off sulphur and phosphorus impurities. Carbon can be added to reduce melting point. High carbon cast irons can melt at temperature as low as 1200°C. There are plenty of direct uses for grey iron. For high quality steels melting temperature will be 1400 - 1600°C. The higher end is for low alloy steels and mild steel. Low alloy steels will dominate demand on Mars. But cast irons will have significant uses, especially in structures and machine housings.
Last edited by Calliban (2025-03-19 07:05:03)
"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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For Calliban re post in Iron topic ...
http://newmars.com/forums/viewtopic.php … 49#p230449
Thank you for providing this summary of the results of the studies reported in the paper you found.
Please continue working in the Iron topic. I am replying here to try to keep your ID visible on the forum Active list.
In a recent post, you suggested that the temperature needed for reduction of the ore might be achieved mechanically, because temperature rises with pressure.
As far as I know, temperature rises linearly with pressure. But as you pointed out, the researchers appear to have found a non-linear relationship between temperature and pressure in this particular situation.
My question is... could there be a sweet spot where the mechanical increase in pressure causes a temperature that matches one of the values reported from the research? It is possible such a sweet spot is visible right there in the numbers, but a graph would be a helpful aid in understanding.
I'm also concerned about the problem of non-iron materials present in the regolith scooped up for processing. Is that a problem? If iron can be extracted using an electromagnet, then perhaps the non-iron materials can be separated quickly and easily.
I wonder if the pressure and temperature would have any beneficial effect on the non-iron part of the regolith?
Reminder ... please continue working in the Iron topic.
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For Calliban .... the story at the link below caught my eye...
https://interestingengineering.com/scie … oup=test_a
Apparently this research is related to heavy element formation.
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For Calliban re post in Void's Accumulation topic: https://newmars.com/forums/viewtopic.ph … 08#p230508
Thank you for engaging with Void in this interesting discussion.
It ** seems ** to me the researchers Void found are working with water as an alternative to high pressure gases, such as are routinely used in HVAC systems.
It seems to me that trying to maintain water in a slush state would present significant management challenges, but setting that aside for the moment, my impression of the work Void showed us is useful for either heating (a home or business) or for cooling.
The heating comes into play if the home creates slush by extracting heat from water supplied by the utility. The slush is then returned to the utility. The slush will pick up thermal energy on it's way back to the utility.
The cooling comes into play when slush is admitted to the home or business and used to exact thermal energy from the air, yielding water which is returned to the utility.
The question ** I ** have, and which I'm hoping you and Void can at least consider is:
If we compare the phase change of materials used in existing HVAC systems to the proposed slushy water concept, which is more efficient?
The high pressure systems in HVAC systems today certainly work. They are installed all over the world.
A slush system would appear NOT to require high pressure, although it would require ** some ** pressure to move the slush around.
One of these alternatives is more efficient than the other.
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For Calliban re new post https://newmars.com/forums/viewtopic.ph … 47#p230547
Thanks for the post about simplicity, with the specific example of cable connected systems.
While I live in a flat terrain, it is punctuated by tall buildings. It crossed my mind that your vision of water lifted cars (or trains even) might work in an urban setting. The amount of electricity required would be the same, but perhaps there might be a water harnessed system.
I stopped in to drop off some work by GW Johnson on one of kbd512's ideas.
The idea of simplicity rang a bell .... kbd512's idea is to use solar energy to create propulsion. This is an old (1950's) idea that kbd512 brought up to date with modern optical fiber technology used for architecture (on the one hand) and communications (on the other).
A simple idea does not necessarily translate to simple procedures to implement it, and the small team working on kbd512's idea is running into plenty of them. There appears to be a very good reason no solar powered propulsion system exists.
Thanks for reminding us that occasionally simple ideas really ** are ** simple to implement.
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For Calliban re material science...
kbd512 and GW Johnson are working on updating a concept for use of solar power to provide propulsion.
Work is progressing well, but a significant hurdle looms a short distance ahead, and I'm hoping you might have a suggestion to help.
The problem to be solved is how to transfer force from the engine to the structure of the space vessel.
In a traditional rocket engine, propellant is available to cool the base of the engine, which delivers force to the frame in which it is mounted.
That propellant is also used to cool critical components such as the nozzle and the expansion bell.
In the solar powered propulsion system, the need for cooling is greater than for chemical rockets, because optical components must be cooled as well.
You have often reminded NewMars readers that certain materials (such as those found in the crust of the Earth) have poor thermal conductivity.
The question I have is whether there is a material available that combines great compressive strength with poor thermal conductivity?
In the case of the optical engine concept, the ton-force that might be achieved is 1/2 (500 kg ton-force) and the temperature of the exhaust is on the order of 3000 Kelvin. The fuel flow is on the order of 2 kg/s of liquid hydrogen.
One of the concepts under consideration is an engine that is heated externally, so that it carries thermal energy into it's interior by conduction. That material will have high thermal conductivity, as well as the ability to survive 3000 Kelvin. However, that material will be glowing hot, and possibly white hot. Without a suitable material to separate that hot component from the frame of the ship, the engine would melt it's way through the ship like a hot knife through butter.
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For high compressive strength and low thermal conductivity, I would recommend magnesium oxide.
https://www.azom.com/properties.aspx?ArticleID=54
See also: https://nvlpubs.nist.gov/nistpubs/jres/103/4/j34sli.pdf
Thermal conductivity declines as temperature increases. As the engine will be operating in vacuum, you could also incorporate porositity to reduce thermal conductivity even further, with some loss of compressive strength. The thrust of 0.5 tonne-force is a quite modest. If it is distributed over 1m2, it amounts to a pressure of 5KPa . So the material probably does not require a lot of strength. Vibration could be a problem, as magnesium oxide is a brittle ceramic.
Last edited by Calliban (Today 09:03:27)
"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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