Ken Fabian

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Everything posted by Ken Fabian

  1. Alternative to space suits

    Being able to work safely without holding on - and without a permanent tether - seems like a necessary threshold for serious construction work in space; much too limiting of work potential otherwise. I don't see that booted feet are that much use for holding on anyway. NASA added them to space suits (Manned Manoeuvring Units) , although they discontinued using them, because of that drifting off issue I suppose. I don't think the issues are insurmountable, whether with single person "capsules" or space suits. I still think that anything less than independent movement will limit a space worker's efficiency and effectiveness - and given the high costs of getting them there as well as the innate difficulties of working in zero gee anything that improved their effectiveness is surely important. Easily avoided - use soft jawed grabbers. Although I do wonder if serious in-space construction work would be best done within some kind of enclosed safety barrier, to prevent both workers and materials drifting away.
  2. Alternative to space suits

    Wouldn't a small capsule - that has external arm/gloves - be more practical for working in free fall than a space suit with legs? Seems like legs are mostly not used on space walks and having space suits with them adds complications that serve no real purpose. You could pull your arms back inside a capsule and scratch your bum - do all those necessary things like eat, drink, piss, blow your nose or wipe off sweat. Also you could have access to the essential hardware, in case. A capsule wouldn't have to have a lot of internal space. It would also be possible to have mechanical grabbers and tools operated by internal controls. Any designs for such a thing out there?
  3. Alternative to space suits

    I don't think an astronaut would use feet as well as hands on a ladder (why a ladder at all?) in zero gee - and I'm not suggesting a capsule that is much more massive than a space suit, that could not be pulled around by hands. But would much movement be done physically like that? I would think micro jets would handle most movements and do so more easily than clambering around. I read somewhere that most manual tasks in zero gee take about 2.5 times as long as in gravity - just on the basis of efficiency of movement jetting around would beat clambering.
  4. Alternative to space suits

    Swansont - I was thinking gyroscopic stabilisers for maintaining orientation - I would expect space suits to have those too - as well as grabbers of some kind to anchor with and give resistance to work against. I don't doubt there would be situations where booted feet would work or spaces would be too tight for even a smallish capsule - not that suits aren't bulky and awkward too - but wondered if it may be a requirement for being able to operate inside a space vessel, if only for emergencies, that has a real necessity for legs. Yet most outside work wouldn't need legs and working for long periods ought be easier and more comfortable in a "pod" or capsule, even if it's only just enough room to pull arms back in and deal with body's needs.
  5. Hardest word for you to spell

    Why the exception for pronouns? Anyway, usage is the final arbiter.
  6. Hardest word for you to spell

    Neighbour - which is often spelt missing the "u" - always had me struggling. I use "it's" when I'm informed it's supposed to have no apostrophe - ("it's apostrophe being both wrong and superfluous"). I dig my heels in and use it anyway, in line with apostrophe as indicator of belonging to; perhaps common usage - and I'm not the only one - will end up making it correct.
  7. Woodworking: Amateurs, Craftsmen, & In-Between

    Thank you. I've been pleased with the end results - and have enjoyed the learning process involved. I'd wrongly imagined that style of woodworking would be intrinsically easy and was surprised at the challenges it presents. I began with what grows on our own land, harvesting the poles - more demanding than it sounds to preserve the natural surfaces without bruising or blemishes. I was making the tenons with draw-knife and spoke shave, moved to using hole saws and cutting away the excess around - having to grind down spade bits to get the right fit - and only much later discovered there were such things as a tenon-cutters and forstner bits, which are like giant pencil sharpeners and clever hole cutters for larger diameters. Whatever you have in mind, it's likely there will be some kind of specialised machine or tool out there. Yet there is a lot of satisfaction working with hand tools - which is good because I've found myself needing them again and again.
  8. Woodworking: Amateurs, Craftsmen, & In-Between

    I enjoy working with round poles, only rarely sawn or dressed timber -
  9. Vertical Farms: Ethanol Fuel

    I'm not sure vertical ethanol farming would manage 3 acres per floor. Maximising the area exposed to sunlight would mean limiting the area to that which allows sunlight to penetrate. Where vertical farming makes effective use of sunlight it makes equivalent large areas that are shadowed; you can't pack them too closely or they shade each other. Light will penetrate mostly from the sides rather than above; no light coming from above will reach the floor below the top one. Ultimately no more sunlight is available than with horizontal farming. Replacing sunlight with artificial lighting would introduce a major energy input in a process intended to maximise energy output - and even if the lighting is high efficiency, plant conversion of light to energy is not - more than 2% of the sunlight converted is considered very good. That may be improvable by selection, breeding and genetic engineering - but enough? Artificial lighting is not so good; it has to use sunlight as it's principle energy source to deliver more energy than it consumes. The innate usefulness of biofuels has been based on the fact that ones like wood just grow, often on agriculturally marginal land, without cultivation and with minimal processing. I suspect the much higher efficiency of Photovoltaics combined with electrically driven chemistry has greater potential to produce transportable liquid (or gas) fuels. How well they can compete with (still improving) batteries will probably be revealed over the next decade or two.
  10. Stephen Hawking says we have 100 years left

    I think space is a lot harder to colonise successfully than people like Pr Hawking are saying. I also don't think "preserving the species" or preserving our civilisation is a motivation that will work; colonies will arise as a flow on consequence of economically viable exploitation of space resources by a successful, not a failing, Earth economy; those economic activities have to be the enabling motivation and some form of self reliant colonisation may, in time, be an emergent outcome. Outposts are one thing - everything they rely on is a product of a large, successful, resourceful Earth economy. Self sufficient colonies are something much larger and more comprehensive - they need to be the large, successful, resourceful economy. If they aren't then they won't be able to make the high tech essentials survival in such places requires and they won't thrive. If they aren't economically viable outposts - and I don't think there is any resource on Mars that cannot be mined, refined and delivered to customers more easily and cheaply here on Earth - then they won't become the successful economy they need to be to survive without support. And I wonder if even a multitude of space colonies would still be more at risk of extinction than people on Earth and besides being reliant on a lifeline from Earth, there is a strong likelihood they could end up calling upon Earth for rescue; we cannot ignore just how extremely harsh and unforgiving the destinations on offer really are. Unlike the historic examples of colonisation, this grand dream relies on exceptional, purpose built - yet to be achieved - technology, rather than the thoroughly proven sort that was in every day use. With some extraordinary technological leaps, perhaps the economics of using space resources will shift from being prohibitive to become compelling but I'm not sure it's something that can be achieved incrementally; the giant steps require a huge pre-investment and that level of investment is unlikely without the compelling economics of a compelling business plan.
  11. Magnetic Reconnection & Atmospheric Currents

    Any presumption that climate scientists are incompetent and that the science linking greenhouse gases to global average temperatures and climate is fundamentally flawed is going to fail - because they are not incompetent and there is no evidence they dismiss or reject any genuine and demonstrable influences on climate. Take care that you do not fall into the mistake of dismissing out of hand any genuine and demonstrable influences - like Greenhouse Effect and atmospheric aerosols and surface albedo changes in order to support your hypothesis, which you have not yet demonstrated to be a significant, let alone more significant influence than they are.
  12. Trump to recognise Jerusalem as Israel's capital.

    Perhaps it's a cunning plan - fan the flames of conflict around the world in order to fix the US deficit by increased exports of military hardware.
  13. Of course the doctor tells the patient; if the PSA levels are indicative of potential prostate cancer then it's important that follow up tests are done. To withhold such information would be negligence/malpractice. I suspect anyone who has gone through the sex change thing would be well informed about the medical implications, including the ongoing potential for prostate problems.
  14. Origional solution to Achilies and tortoise paradox

    Well, I wouldn't hire Zeno as a running coach! "See where the competitor in front is? That's your finish line... no, where he is now! Dammit, he keeps moving! Where he is now, Now! Now, now, no-, n-, n- ... Oh, you've passed him! And I thought that wasn't possible!" I never thought it was much of a paradox - more an example of a mis-stated problem leading to a mis-taken conclusion.
  15. The North Korea Problem

    TenOz - I'm not serious in the sense that I doubt anyone who has any actual responsibility in this is interested in or will be influenced by my 2c worth. I freely admit to a lack of relevant expertise and, usually, I prefer to defer to experts who know a lot more than I do. No doubt there is an element of Dunning-Kruger in my simplistic alternative solutions - that if I knew a lot more maybe I might see why they can't or won't help. And yet it doesn't take an expert to see there is an enduring absence of expert solutions that do work. Where there is a high level of disagreement amongst experts I suspect there are things that are, if not overlooked are overshadowed - most of all that there are competing and incompatible motivations at play; retaining power and keeping up appearances internally are not the same as securing enduring solutions. Kim Jong-un's posturing is for internal consumption, as is Donald Trump's. I suppose helping North Korea economically in order to ease them towards more normalised international relations is too counter-intuitive despite the regime having come to depend on the existence of outside enemies for legitimacy and solidarity. I doubt there is any genuine plan to attack the US or, with the exception of South Korea, it's allies - although I suppose passing on WMD's to crazies that would use them is a real possibility - yet that threat would also be reduced by improved economic circumstances and more normal relations.
  16. Why doesn't truth matter & middle ground

    The concerns about climate mitigating actions have always been much broader than those directly involved in fossil fuels. The prospect of more expensive energy motivates all kinds of ordinary people and business leaders to oppose strong climate actions - Tar's winter heating for example. A whole new range of regulatory requirements around emissions motivates all kinds of ordinary people and business leaders to join in opposition to emissions regulations - without any direct consideration of the validity of the science on climate. Those concerns flow through business associations and lobbyists to political parties and politicians and through their own workforce as fears for job security within businesses with rising costs and reduced profitability. The concerns about energy costs and reliability as well as government regulation in an area formally free of it are shared by those with no direct involvement with fossil fuels. These mostly economic concerns tend to have more direct and immediate impacts on choices than longer term and broader concerns about climate consequences, no matter that over the longer term the accumulated and irreversible climate impacts will include significant and accumulating economic costs. Studies of the relative costs seem to agree that prevention, even with more expensive energy is more cost effective than adaptation. It's never been up to environmentalists or manufacturers of solar panels to solve the climate problem - that has tended to happen by default, by the failures of more mainstream influences to lead and act decisively. And I think to some extent perceptions of climate change being a "green" issue has been created and reinforced through deliberate efforts to discredit legitimate concerns by associating the issues with extremist ideology and irrationality that has tended to be viewed as impediments to economic growth and the benefits that delivers. That climate change has serious and enduring economic consequences, affecting long term prosperity and security is a truth that can always be put aside in the face of more immediate business and living cost concerns. Except that it does have consequences and costs. Those associated with political environmentalism or who are optimistic about the use of solar power do not have a monopoly on solutions. What I often see is disagreement with the solutions some offer as reason to reject strong actions to reduce emissions - including by misrepresenting the fundamental science about climate change and expert consideration of the consequences - rather than as reason to strongly promote alternative solutions.
  17. The North Korea Problem

    Rather than dropping bombs maybe we should be dropping aid packages. Rather than closing off trade maybe we should be dumping low cost consumer goods into their economy. If changing this enemy's mind is the objective then anything that changes their mind can be considered a weapon. Not that I am being entirely serious or expect anything I say will change any minds but I can't help but think that it's the sense of being a state under siege that unites the North Korean people behind it's leadership and ennobles their hardships and sacrifices , so actions that reduce that siege mentality should deserve consideration. Action to deal with them look like the exact opposite of that. I do remain sceptical of the long term effectiveness of instigating insurrection and arming insurgents as a solution, as I do with enduring interference by outside powers in the internal affairs of nation states; the legacy of doing so in the Middle East does not fill me with optimism about the outcomes.
  18. How to cheaply and efficiently power a Moon Base

    I have reservations about massive global expansion of use of nuclear around the world as a primary emissions reductions strategy but that's for another thread; enough to say I think the dominant environmental, security and weapons proliferation concerns won't apply to use at a moon base. Or the same level of concern over cost. Safe and reliable launch would be important. I believe the USSR put 40 or so small fission reactors into orbit over the years. There are probably some still up there, but dumping them back into Earth's oceans when done isn't something I'd like to see emulated but that wouldn't apply to this. It would also not be up to me! I don't know about the waste heat issue - it would be a serious consideration during 340 hours of continuous sunlight, where temperatures can get over 120 degrees C, with another 340 hours of night with temps down to minus 150 C. But I'm not sure it would be insurmountable. If radiative cooling is directed to open space and it is shaded and insulated from radiant heat from sun and surrounding sun heated lunar surface that might be sufficient. Building them on site seems problematic - these are complex technologies with exacting standards. It's unlikely they even can be built entirely or even mostly with locally obtained lunar materials - I would expect modular reactors, probably purpose built to handle the changes from Earth gravity to high G acceleration to zero gee to, finally, low lunar gravity. But we are discussing a base or outpost, not a colony expected to be able to make it's own equipment.
  19. How to cheaply and efficiently power a Moon Base

    Frank, I think bringing along a nuclear power plant would be a serious contender for powering any Lunar base. For one thing it means the base can be sited where it's best suited for it's purpose rather than sited for utilising solar power. Solar could still be a useful additional power source, with high energy projects scheduled for Lunar day periods. I'm not sure what to think of the tethered payload delivery system. Wouldn't the capture of moving mass result in significant instabilities? Can the payloads be delivered in the right direction with the right amount of momentum? I suspect there will be more straightforward ways to deliver payloads.
  20. How to cheaply and efficiently power a Moon Base

    I got pulled up before on another forum by suggesting this - because of axial tilt (1.5 degrees I think?) and the moon wobbling in it's orbit (nutation) the poles are not constantly sunlit. I have heard claims that some polar mountain peaks may be constantly lit (named Peaks of Eternal Light) but I don't believe any have been identified. But having several solar arrays at different longitudes, close to the poles, could be linked by much shorter power transmission cables than doing that near the equator. My scepticism that lunar bases or colonies can pass any kind of benefit vs cost analysis remains strong, but as thought experiments I still find these questions interesting.
  21. Compostable food packaging

    Studiot, it's not that I think reducing the packaging isn't a better option, just that I think it's a less achievable option. Just as making things that last is less achievable. It seems to me the degree of change within manufacturing, food distribution and retailing to achieve those better outcomes involves a greater degree of regulatory intervention; the potential for retailers to raise the PR profile of their businesses by adopting different packaging is greater than the potential for getting the major retail chains, that like the way pre-packaging streamlines things, to greatly reduce packaging. I still think you are missing a lot of what I have been saying. I did mention methane utilisation, more than once. But that it's far from universal - as a source of atmospheric methane it is not from the landfill that utilises it but the landfill that doesn't; it probaly will increase in use but I think it is better that the food waste not be incorporated into the landfill to make landfill a methane source. Which I think is greatly impacted by ease of separation; if the past-it's-use stuff can just be thrown into a bin for biorecyclables, without needing to be unpacked, less of it will go by default into the bin for landfill. Deplore the waste all we like; it's a fact to be dealt with. Also think that civil engineering projects, like flood mitigation, as a secondary use for landfill can be done even better if that biological material - and toxic material content - were reduced. If such projects have a sound basis they ought not be reliant upon landfill to get done.
  22. Compostable food packaging

    So much food comes in some form of packaging - from supermarkets and food outlets - that it represents a huge waste stream. A lot of it is - technically - recyclable, but a lot of food packaging ends up contaminated with food residues and almost all recycling, even when it's done well, is more correctly downcycling. ie materials can be re-used only at lesser quality and usually only a few times before ending up unusable. Separation of biological waste from other kinds of waste seems to me to be the most basic kind of separation and biological waste is the kind that can be most completely and efficiently recycled, via biological means. I can see that the kinds of foods that come in cans and glass, for long duration storage would be the most difficult to repackage, but is it technically possible? What might be the technical problems with all the short lived packaging being made of biological materials that can be composted or fed into sewage waste streams that can recover safe and usable biological materials?
  23. Compostable food packaging

    studiot - We may be more in agreement than not. I understand dismay and frustration with those in positions of public trust and responsibility letting us down, engaging in gesture politics rather than well considered and well implemented policies; here in Australia for example, the national climate and energy debate is currently heading towards farce - only, given the seriousness, I don't find it funny. Why food packaging? Leaving aside the GHG contributions - which many people are surprised to learn far exceeds in weight and volume that of 'solid' waste - the largest component of our own household's waste is food packaging. Chickens, worms and garden deal with our food waste but we are not typical. A lot more is, supposedly, recyclable, but I still say 'downcyclable'; a couple of re-uses at lesser quality at best and it ends up in landfill. Very little aluminium for us (and less glass as plastics replace it for many food items) but, like I say, we are not typical. I spent time with my mother in Sydney in her infirmity and food waste separation was not even an available option within the "retirement village"; the amount of food waste going unseparated surprised and shocked me. Yes, it often is commonly an option, with separate bins for recyclable plastics and metals as well as those for food and garden waste but my understanding is that a lot of that plastic packaging makes it's way into food waste, food in the recyclables and both in the 'general waste' that goes to landfill. Good intentions and even good implementation are hindered by that. It's all very well to say much of that packaging is not necessary - absolutely I agree; I just suspect that choice of packaging at the supplier level is simply more achievable than eliminating it and would lead to ease of and higher rates of separation at the household level. Like I said, what comes out of composting - and liquid waste processing - can and does have economic value. And costs for processing it of course - but reducing costs of processing at the waste end is worth some attention. I don't know about globally but a quick search showed the US landfill is it's third largest source of atmospheric methane, because of food waste - which is on top of better managed sites where methane is a spin off that is utilised. I don't see reducing it as insignificant. John - Where the materials have sufficient monetary value there is motivation - and better rates of recycling. Where they don't is where it isn't done so well. Not so sure that heat is or should be the primary means of dealing with residuals in metal or glass containers - rinsing and incorporation into liquid waste streams would be more usual, with heat for final residues - air pollution issues? It may be that no viable and cost effective replacements for metal, glass or, increasingly, plastics will emerge - and recycling methods for those will continue to improve, even to seeing less of it being 'downcycling' with more reuse at the original quality. I still think it's worth some efforts to explore new possibilities.
  24. Compostable food packaging

    John, I'm interested in whether that line can be redrawn, for ease of separation. Aluminium is, yes, amongst the most recyclable of materials and drink cans get recycled more than most other recyclable materials around here because scrap metal businesses will pay money for them. People and charitable organisations collect and cash them in so the sorting is better done. But a lot of food packaging is widespread, not well sorted and is commonly mixed with food remnants. Some is already compostable but a lot of it isn't.
  25. Compostable food packaging

    Reading back over this thread I think I pointed out more of the benefits of landfill than you have - flood mitigation through, I thought by land reclamation, although I'm ready to be corrected, as a spin off benefit is about it. Nor have I suggested it does not serve a valuable function or that we not use it. Have I been a loudmouth, know it all environmentalist by asking if we can improve the management of waste by suggesting we may be able to improve recycling of food packaging by preferentially using biological materials that can be recycled biologically into economically and environmentally useful products? I would suggest that, whilst use of methane from landfill - a product of large amounts of those materials in it - is being utilised more, it is not a good reason to fail to consider methods for making better use of those materials. I have no problem with people campaigning about environmental concerns. I think that an absence of people who do would, given the capacity for political systems to neglect important issues in the absence of political activism, be a net step backwards. The capacity for policy makers to put populist gestures ahead of well thought and effective policy remains significant but that is not the fault of political activism.