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Ken Fabian

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Everything posted by Ken Fabian

  1. Since I don't think any past rate of crewed space missions projected into the future can properly represent genuine expectations for technological advancement - and the sufficient motivations for ever more distant crewed missions (allegedly colonisation) are assumed and assumed to be sufficient - I remain deeply dubious that these kinds of studies can tell us anything useful. I think space exploration will continue to be best done remotely with machines and the motivations for and benefits of crewed missions aren't entirely clear to me, beyond feel-good human interest; it isn't because they will do mapping, surveying, sampling better. Including them will reduce, not expand the overall mission capability, with astronaut safety and comfort coming at the expense of other, more useful payload and capabilities.
  2. We will get samples from within the solar system but it looks unlikely in the extreme that we will ever get to examine samples from exoplanets, ever - so we will have to make do with what astronomy can detect. If we want evidence of ETL within our lifetimes it has be either artificial emissions - intentional and unintentional - or biosignatures, not samples. I am not sure what is meant by "theory of life" - observed and hypothetical biological chemistries? I suspect there will be limited chemical pathways for abiogenesis to make life and that determining what those are (and how limited) will be primarily a matter of modeling. Of course we will need to know what signatures abiotic processes can produce, to reduce the possibility of misreading signatures that are ambiguous.
  3. A breakdown of the available nutrients seems appropriate; as others point out getting seeds to sprout is not indicative of an adequate growing medium. About the best it does is indicate an absence of toxicity to plants, or was the "soil" washed or otherwise modified? Mars "soil" would definitely need to have the perchlorates washed out as a preparatory step. NPK are just the big ones where plant nutrients are concerned and for a great many plants the presence of soil biota is critical, including for making usable nutrients from raw rock and mineral material. But I am not convinced this kind of experiment has much value and suspect it is more about keeping the hype about desirability and inevitability of human occupation alive; being able to grow plants in Moon or Mars "soil", when suitable soil, with it's mineral abundances and mineral absences is just one of a great many requirements for viable agriculture will give a misleading impression - almost inconsequential compared to some of the difficulties. On Earth the kinds of construction costs of suitable habitat like the moon needs would send farmers broke before they ever planted anything. And doing it here would be much easier and less costly. Economics is not inconsequential - if providing basic needs takes more economic resources than what the available labour can produce the enterprise will fail; some very big payoff is needed to justify Earth's subsidies.
  4. Coming into this a bit late but - I think cannabis should be fully legal for adults - like alcohol it is widely used and widely accepted and I think prohibition causes more harms than it prevents. A significant number of people who are otherwise law abiding see the police as enemy because cannabis (and other drug use) is illegal. Counseling and rehab as well as education make better use of taxpayer funding than policing cannabis. Other drugs should be legal to use and possess (in small amounts), with efforts to limit availability, but supplying them outside of medical supervision (which may be indicated for confirmed addiction, as harm reduction) should probably not be legal, although I suspect education and harm minimising for users will still give better outcomes than harsh policing. Anecdotally crackdowns on cannabis supply tended to be followed by increased use of other drugs that have more significant medical and social harms, including alcohol. I remain a bit skeptical of significant increase in society wide incidence of psychosis and mental illness from cannabis, suspecting it is one trigger amongst many for susceptible people rather than being a specific cause. The reality around here (rural Eastern Australia) is that policing of cannabis is sporadic and the police don't have their hearts in it, and the penalties are minimal - to the point where Magistrates have actually berated the police for wasting the courts time with arrests of people growing a few plants. The helicopter raids on growers are ineffective - occasionally a very large crop is found but most of that policing is of small crops - a tiny fraction of them - and the police presence is for appearances sake.
  5. PS - I do wonder if they'd have done it differently if they were planning that farm now - solar PV with battery storage instead of solar thermal and thermal storage, powering reverse osmosis rather than evaporative desalination. Most new solar desalination is PV + reverse osmosis. But unless your water needs are low or the demand is high value it won't be cost effective.
  6. Reality is different - skilled labor and existing technologies, construction techniques and supply streams for materials like glass already grows significant amounts of vegetable crops with desalinated water in Australia. Sundrop Farms - It is an example of concentrated solar thermal power being used cost effectively, providing on-site power as well as desalination. Without the climate controlled greenhouses it probably wouldn't work; the local climate would not support outdoor growing and they reduce overall water requirements. It has contracts with one of the largest (the largest?) supermarket chains in Australia. These chains are ruthless with keeping supplier costs low; if it weren't cost competitive with other growers that wouldn't happen. Even the "climate responsible" PR benefits wouldn't be enough. "We use the sun’s energy to produce freshwater for irrigation. And we turn it into electricity to power our greenhouse to heat and cool our crops."
  7. I wonder if this is the most common sort of atheism - people who don't know and don't care. And the most common sort of theism is going along with and repeating the common beliefs of those around us, without much thinking about it.
  8. Like others here I tend to set aside the spooked reaction in favor of more rational explanations. We have a much more comprehensive knowledge of the world around us to draw on than at any time in our evolution, giving confidence in (the more mundane) explanations over the supernatural. I think our capacity for dreaming and imagining is both a strength and a vulnerability - and the imaginary can be spoken or sung or otherwise communicated in ways that affect us emotionally, which I suspect amplifies or reinforces. When the explanations we imagine are close to reality it helps us solve mysteries and real world problems. When the real world responses we make to what we imagine is going on advantage us rather than disadvantage us it helps us. In the presence of imaginary dangers we may do things that help against real dangers - staying near each other and patrolling the camp perimeters for fear of imaginary predators can protect against real ones.
  9. Yet it is currently smaller in extent than at any time since records were kept. Big swings, from record high to record low over a short period. https://www.scientificamerican.com/article/antarctic-sea-ice-hit-a-record-low-now-scientists-think-they-know-why/ The recent extraordinary record high temperatures in Antarctica - coincidentally at the same time as breaking temperature records in the Arctic - came after the record low ice extent, so was not a factor. Antarctica's ice sheets are also losing about 200 billion metric tons of ice a year.
  10. At the household level - it is looking more cost effective for us personally to replace our dying solar hot water system with a heat pump hot water system and run it off the rooftop solar. Note, I'm in Eastern Australia with a mild climate and good solar availability. The power used wouldn't deprive us of any, but the amount of electricity exported back to the grid would be reduced, foregoing a small return payment. The upfront costs are similar, with heat pump costs declining but solar hot water systems struggling to achieve further cost reductions. Why a very simple, direct heating method with no moving parts should be more expensive than a heat pump isn't clear to me but I suspect material costs account for a lot of it - a lot of stainless steel, copper, aluminium and glass in a domestic solar hot water system. Installation of heat pump hot water at ground level is easier too. Durability matters but assumptions that - having no moving parts - direct solar will last longer isn't clear. The repeated heating and cooling of the collectors takes it's toll - it is leaking now at a joint within the collector part and more hassle than it is worth to attempt repair. That part has it's own fluid, originally glycol but now just water, being topped up regularly until we can replace the system. For electricity grids photovoltaics have significant advantages over solar thermal regardless of energy conversion efficiencies. The panels don't need precise alignments or tracking. Little maintenance is needed. They are lower cost per watt hour compared to high temperature Solar Thermal - enough lower that it is cheaper to add more area of panels than use tracking. Finding room for more isn't an issue. Solar thermal's mirrors are technically demanding - precise surfaces and precise solar tracking for each mirror are essential. Steam turbine efficiency in general is rarely above 50% - more like around 30% - but I'm not sure what they are for working solar thermal plants. The capability to store energy as heat - molten salt usually - should be one of the significant advantages but I think including it has actually made the economics worse, not better; attempting to be some kind of drop in replacement for 'baseload' fossil fuel plants was a mistake I think. It added costs but without a clear market and grid demand for stored energy the grid managers just call on lower cost power from elsewhere and the storage component of these plants fail to earn money. Photovoltaics pass off the load leveling role to other elements of an electricity grid, which is normal foer how grid managers deal with the ups and downs of supply and demand. Calling on power from somewhere else has, so far, been cheaper and easier than each generator providing it on site. The economic of solar thermal storage may change as the value of stored energy becomes more explicit within electricity markets.
  11. I think the definition of "therefore" is presenting real problems too. Too many misunderstandings backed by faith rather than evidence or reason. Throw enough doubts around about abiogenesis and evolution amongst people who know little about either and even the most outlandish hypothesis - a supernatural being did it - can sound reasonable. It doesn't work with people with even a basic understanding of biology and evolution.
  12. Peterson will use his keen perception for which hypocrisies of liberals presses conservatives' buttons - showing almost as much contempt by that for those unthinking conservatives as the "hypocritical" progressives - to relentlessly criticise appointments by US Democrats for being politically motivated but, being a politically partisan voice, will refrain from and deflect criticism of brazenly political appointments by US Republicans; despite not being a US citizen he has chosen his side. Of course I'm disappointed that any US President or political party feels it is necessary to stack their highest court with partisans or choose candidates for the sake of public perceptions, but that is the way many of them "play the game". I suspect the new Supreme Court judge - not being white and male and watched hawkishly by conservatives - is more likely to be scrupulous than some of the ones there already, such as Trump appointed.
  13. They stop being atheists with that belief. Taking up religion because other people appear more contented or happy with it could be a rational choice, especially if atheists face persecution, even to wanting to believe and at times feel like they do. And at other times, not. Is that an in between state or a switching between theist and atheist? People are complicated and even the rational are not always rational.
  14. Those that live by the truism will die by the truism. I daresay Alexander made good tyrannical use of fear, both to motivate his nation(s) and armies and to weaken the responses of his enemies. .
  15. The political players who thought branding their legitimate political opponents as traitors was a good idea probably saw it simply as a small but effective way to build a reluctance to change sides in their voter base. The larger consequences of that probably didn't concern them - winning at all costs was the point. But political discourse and democratic elections are the principle ways to avoid deciding things by violence - ie to avoid winning at all costs turning everyone into losers.
  16. I expect some attempts at doing so - parents wanting children who are better than they are in places where that kind of choice is allowed and available, or authoritarian regimes wanting workers and soldiers more capable than their rivals (but probably wanting them to be more obedient and content with their place too). But I think the former depends on developing the means using comprehensive and reliable modeling of the results rather than experimenting on humans - parents will want confidence the changes won't cause unexpected harms but likely won't support trying it out on human subjects as the means to find out. The powerful people who want better soldiers, servants and slaves won't care about the human costs. They will likely want control too much to allow too much super free thinking. Practicing eugenics to enhance or inhibit various traits is possible but I'm not convinced that the end can justify the means. I also suspect a society that is ordered enough to support long term eugenics within it's population may be intrinsically unhealthy. Sorry Beecee, I'm not going to watch an hour and a quarter to get to the "virtually said yes" bits. Hawking was an amazing man with an amazing mind who had big ideas and shared your enthusiastic optimism about humanity expanding into space but his expertise was theoretical physics, not predicting the future. Whilst bio-engineering humans for exotic environments appears a way to make successful colonisations of such environments more likely it takes a whole lot of unlikely hypotheticals on top of hypotheticals to get there. Most proposals for people in space start with making artificial environments close to what humans evolved with, with technologies ordinary humans are capable of mastering. Whilst isolated small populations will end up sharing traits, enough to be recognisably different to other populations I don't see how that would lead to becoming superhuman. Survival in space is unlikely to be easy so being well ordered is probably essential but that degree of order may ultimately be an impediment - any adventurous or rebellious urges may need to be channeled or suppressed to prevent them being counterproductive.
  17. Not sure what is meant by "the energy crisis". I thought first you meant the climate change challenge of replacing dirty energy with clean but suspect it may be the short term shocks from Russia's Ukraine invasion you are referring to. I have no doubt that European nations are quantifying near term available energy resources and requirements in mathematical terms - something nations tend to do anyway, just with more urgency at the moment. But whilst finding the optimum based on those factors may be possible there is politics and balancing various interests to complicate things. EG - clearly it is given that German Greens will oppose extending the lives of nuclear plants - but Germans apart from Greens have misgivings too or the agreement to close them would not have happened. Some of those are more about the poor cost effectiveness of keeping them going given they are expensive and they need a lot of work. Other Germans don't care about climate or nuclear and want returns on their brown coal and gas investments. A study showing other options would be better than nuclear will not be welcomed and would face opposition, just as studies showing doing upgrades to existing nuclear plants would help will face opposition. Given we've had more than 3 decades of consistent science based studies showing we need to get out of fossil fuels the growth of their use was (and is) widely supported by the same governments that commissioned and funded those studies - it is clear that doing studies isn't the biggest problem.
  18. These "scientists" probably had a lot of fun speculating - but it was speculation plus imagination, not a science based prediction. Even basing future changes on trends within our species looks problematic, as would proposing there is some ideal form and seeking to define it. The linked articles were not very impressive - and that goes for the source material that got quoted in them. Like - Perhaps that is true based on an average across the whole population, but that can be from a: people everywhere are all getting larger foreheads or b: the proportion of people with the genes for larger foreheads has grown in proportion to people who's foreheads are smaller or c; this is a consequence of change to living conditions, not genetics. a: (if it even could happen) would be evolution across the species but b: would be existing variation within the species. Until and unless some selection process eliminates the ones with smaller forehead our species is one that encompasses larger and smaller foreheads. The conditions that have caused the numbers of people with large foreheads to grow may be shortlived - and that period is so short in evolutionary terms and the changes of the conditions people live in so great that it needs to be established that the difference is genetic change. I expect that, so long as our advanced industrial civilisation doesn't implode, we will have that capability within the current century. If not genetic then surgical and other modification can deliver desired appearances - but without passing them on. No guarantee that everyone would take either option up. 60,000 seems like a number pulled out of the air (or perhaps some orifice). The supposed idealised beautiful human face isn't a universal thing. This is pure nonsense IMO. Contradictory as well - low light but high UV? IF humans colonise space they will make their own environment, including lighting. i don't expect terraforming to be able to make outdoors possible for space colonies. Light intensity may well be reduced compared to direct tropical sunlight or what is used in grow tunnels but will be close to how we do indoor lighting - because that's how we like indoor lighting. Eye size seems more likely to be changed on purpose, because people think they look better. Since no-one knows how different or can know that people of the future will be deeply unhappy about their appearance and there is nothing to do about it if we did know - there is no incentive to intervene.
  19. But it will be inefficient and likely will impact how quickly food goes bad. Food in the door and at the front is likely to be more affected. The fridge will work harder re-cooling itself, with greater use of electricity than a light - with no real difference by changing the thermostat setting, except to make it go colder than before, once the door is closed. Even a low power night light left on might be a better alternative.
  20. Why would good and evil not be subject to cause and effect? Isn't the point about doing good or doing evil all about consequences, ie the effects? Also, is "the law of the jungle?" actually a thing? It isn't a term used much by biologists. Lots of animals are social and engage in co-operative behaviors. Cooperation and Competition both have their place. Even the fiercest warriors can be thankful that they can go home to a community that will care for them when injured or in their old age.
  21. Members here are basing that on decades of scientific studies, that have been built in turn on a foundation of ever improving understanding of fundamental physics and chemistry and of understanding of climate processes. That agreement is not simply a case of our opinions being a majority here but of the majority here being familiar with what those studies have been saying.
  22. A lot of the health issues around radioactive materials are actually chemical in nature, by being chemically toxic and biochemically carcinogenic. Eg, Strontium 90 when ingested will be used in place of calcium in cells and tissues, but then the Strontium undergoes radioactive decay, breaking apart the molecules they were part of (which may become toxic in turn) and becoming Yttrium 90 and then Zirconium 90 whilst releasing alpha, beta and gamma radiation, which induces further unwanted and potentially harmful biochemical reactions in surrounding tissue. Re the Thermal History of Earth there is still a lot of uncertainty but the fundamental processes appear understood. Like heat from compression being ultimately attributable to the formation of the Earth - the energy came with the materials that coalesced to make Earth. And whilst we may not perceive rock as being a good insulator it is in fact a very good one when it is hundreds of kilometres thick, so much of that heat has still not managed to get out.
  23. I don't think it is so simple or so dark. The shaman/priests weren't usually the chiefs and whilst both might have status and power and interests in common each would be a check on the other. Lore and law often bound even the behavior of priests and chiefs. Our prehistoric ancestors were not simple brutes even if - as now - they were capable of brutality. I expect there were sincere and sometimes desperate efforts to call on spirits and gods for the good of the tribe as well as chiefs and dynasties that sought to lead well, with the support of their community. It wasn't always winner take all. And their communities were not powerless; bad things could happen to chiefs and priests that let everyone down.
  24. The flooding in Lismore exceeded the previous highest flood level by so much that many people who believed themselves safe and prepared found they were not. Downtown Lismore (behind levees) expected the ground floors to be inundated but the next level up to be safe - so they shifted valuable goods as well as themselves up to there. And got badly caught out. Being up on stilts was not enough - and gave many people a false sense of security. Between raised sea surface temperatures and raised air temperatures the severity of rainfall events is raised... when conditions suit rainfall. When ENSO is in la Nina phase Eastern Australia gets more air flow from the Pacific Ocean over land - in combination with that warming it isn't difficult to see why this would increase rainfall intensity. During El Nino phase the prevailing air flow is more often from Central Australia towards the coast - and whilst warmer air can take up more moisture, it also takes more water vapor content to reach the saturation needed to induce rain; it isn't difficult to see how that would lead to reduced rainfall. Like sea level rise for The Netherlands with the existing propensity for inundation, being "a land of droughts and flooding rains" doesn't make greater extremes of droughts and floods for Australia less concerning. Quite the opposite. Like with "but the climate is always changing" the susceptibility of the global climate system to natural change makes it more susceptible to change and to reach new extremes from raised GHG's; it would take climate that doesn't change for it to not matter. There isn't much doubt the current Australian government has protecting the fossil fuel industry from emissions reductions ambitions as higher priority than reducing emissions. The Minister for Energy and Emissions Reductions has been tireless on that front. For non-Australians the Australian Prime Minister is bottom right, with the lump of coal he once brought to parliament to attempt to ridicule those who have been calling for Australia phasing down coal exploitation - "don't be afraid" -
  25. You are right. Some blanks are not going to be as significant as others. Some people will be less fearful of the unknown or not need explanations for the inexplicable. But it can be socially disruptive to have competing beliefs or for dangerous beliefs to spread unchecked. I like to think I am rational but I still have the emotive responses to the strange and unexpected. Superstitions I learned as a child can still be triggered, even though I dismiss them as irrational. We are susceptible - our powers of imagination can be a vulnerability as well as a powerful tool to provide understanding and predictability.
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