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Our clean energy ups and downs

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So in the light of the federal government’s most recent abandonment of an energy policy, it’s about time for a more positive update – perhaps – on what’s happening in the field of clean energy around Australia. 

I should start by plugging the Renew Economy blog/website, the best source for info on what’s happening round the country, both technology-wise and politically. Giles Parkinson has recently reported there on an important change of tack from the conservative International Energy Agency (IEA) vis-a-vis fossil fuels. The IEA has long been a big promoter of coal but last year it shocked its conservative backers by admitting that the coal boom was over and that the future was with renewables. The IEA has just published its annual World Energy Outlook, which recognises that coal production will have to be substantially reduced if we are to meet Paris targets. It notes that PV solar costs have dropped to the point that it’s the cheapest energy option in most countries, with wind power also becoming much cheaper and more viable. China, while still a massive consumer of fossil fuels, is leading the way in rapidly reducing that consumption.

Meanwhile, in Australia… Another report, this time from the G20, reviews the climate action performance of member nations. Called the Brown to Green report, its 2018 version rates Australia’s Nationally Determined Contributions (NDC) targets as ‘insufficient’. That’s to say, they’re disappointingly unambitious and would be likely to worsen the situation if other nations followed. To quote from the report:

The 2018 CAT assessment confirms that Australia’s emissions are set to far exceed its NDC target for 2030 under current policies.

With no guidance or serious interest from our federal government, none of this is surprising, but there are projects completed and underway that give hope for a turnaround, and of course the conservatives are set to lose power in the upcoming federal election. Not that I’ve heard anything much about Labor’s renewable energy plans. 

As reported previously, and elsewhere, South Australia’s Tesla battery, mocked by fossil fuel dinosaurs Scott Morrison and Matt Kanavan, has exceeded all expectations, due to its ability to respond super-rapidly to system breakdowns, and Tesla’s success at Hornsdale has led to more projects here for the California-based company. Victoria’s Bulgana Green Power Hub, a project designed by Neoen Australia, will feature a 20MW/34MWh lithium-iron Tesla battery and a 194MW wind farm about 15ks east of Stawell in west-central Victoria. It should be complete by the end of 2019. The NSW government’s energy network operator Transgrid is purchasing Tesla Powerpack systems to be installed in a number of locations to smooth out variable solar generation and to facilitate growth of solar infrastructure. Small-scale Powerpack systems are already operating in Melbourne and Rockhampton. 

There will be another Tesla battery (25MW/34MWh) in SA soon, at the Lake Bonney wind farm. Interestingly though, the renewables developer Infigen Energy, which will build the battery, is concerned about future batteries investment in Australia because ‘the rules of the market do not yet favour battery storage, and battery storage costs need to fall further’.

In any case, state governments and private companies are forging ahead with clean energy projects in spite of federal indifference and inadequate legislation. One market, though, which seems to be stalled in Australia is the EV market.

And after a quick bit of research, I’d say I’ve understated the issue. According to Behyad Jafari, chief executive of Australia’s Electric Vehicle Council, the global average for electric vehicle purchases is about 2% of all car sales, with Norway leading the way at 20%. Australia’s uptake is at 0.2%, about the lowest in the western world, though surveys have shown that Australians are excited and intrigued by EVs. A large Roy Morgan survey recently found that half those surveyed were interested in buying an EV or a hybrid. So clearly there are barriers to investing in an EV here. Apparently the biggest barrier is the lack of a decent recharging network, according to research, with actual  vehicle cost coming a distant second. With no government action either on infrastructure or on import taxes and charges for EVs, it’s hard to see a big uptick in EVs in the near future.

However, some are optimistic, at least for the long term. Bloomberg New Energy Finance has predicted that Australia will start really getting on board with EVs by 2025. Its analysis of Australia is part of its global forecasting. It predicts that ‘by 2040, some 40 per cent of all vehicles on the road in Australia will have a plug, and 60 per cent of new car sales will be electric’. Only twenty-odd years to wait – nice if you’re young. Again, pressure needs to be applied to what should be an incoming Labor government in the next few months to support the EV industry as well as other clean energy schemes. 

And how about here in South Australia, with the conservatives winning the state election in March 2018? Fortunately, the plans and developments of the previous government are unlikely to be jettisoned because they’re clearly having a positive effect and are popular here. South Australia has been regularly targeted by federal conservatives as a crazy outlier of sorts for its focus on renewables, but the Australian Energy Market Operator (AEMO) has predicted that SA will be sourcing 100% of its energy from renewables by 2025. The scenario here is complex, and I may need to do a few posts to get my head around the issues and the technology, but briefly, SA currently gets around half of its energy from natural gas, and a third to a half from wind. The percentages vary on a daily basis. Solar also produces an increasing share – both rooftop and larger scale commercial solar. Over time, it’s expected that commercial or utility solar will play a much larger role, and gas turbines will be phased out. Utility storage will also be an increasing part of the mix from around 2025. 

I’ll try to get a handle on what’s going on in South Australia in a future post, because at the moment terms such as ‘synchronous generation’, ‘dispatchable capacity’, ‘grid level services’ and even ‘base load’ are giving me the screaming heeby-geebies. And once I familiarise myself with these terms I should be able to apply them elsewhere. I do get the impression though that base load, which has much to do with reliable on-tap energy (because the sun doesn’t always shine and the wind doesn’t always blow) is a term much beloved by fossil fuel heavyweights and derided, at least to a degree, by the renewable energy crowd. So I think I’ll focus first on that in my next post, especially with regard to the new battery storage technology.  

Written by stewart henderson

November 20, 2018 at 6:02 pm

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the amazing physiology of hummingbirds

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The smallest bird on our planet is the bee hummingbird, of Cuba. The average adult weight ranges between 2 and 2.5 grams, with females being slightly larger than males. There are other tiny hummingbirds, including the bumblebee, from Mexico, and the calliope, of Canada and the US. Basically the adults of all these birds weigh little more than a couple of paper clips. Yet, as Jim Robbins reports in The wonder of birds, these featherlight birds are incredibly robust. Calliopes fly from the northern US down to Mexico every winter, often through powerful head-winds and raindrops as big as their ‘eads. They fly back north in spring, early arrivals, living on insects (their principal source of nutrients) until the flowers start blooming (providing nectar, their principal source of energy). It’s an annual journey of nearly 3000 kms.

adult male bee hummingbird

It takes heart to undertake such a journey, and hummingbirds have plenty. The hummingbird heart is the largest of any known animal relative to its size, and its rate has been measured to reach over 1200 beats per minute (in the blue-throated hummingbird). There are some 350 species of hummingbird, all living in the Americas. 

But it’s not just their long-distance flights that astonish, it’s their everyday manoeuvres. They can fly upside-down, change speed and direction smartly, and hover for long periods, even in strong winds, while collecting sweet nectar in vast quantities – as much as 12 times their body weight daily. Their wing-beat speed, which can reach 100 beats per second, is about ten times that of a pigeon, and they have the largest pectorals for their size of any bird. Birds’ pectorals, which power their flight, are always proportionally massive, taking up some 80% of their weight, but hummingbirds are clearly built for flight more than any other, which allows them to remain in the air more or less constantly. ‘It’s their default setting’, says Bret Tobalske of the University of Montana, who studies the mechanics of flight in birds, bats and insects. Tobalske has studied their flight using ultra high-speed cameras and atomised olive  oil illuminated by lasers, so that the revealed air-flow around their wings can help in understanding the mechanical processes involved. He’s also used wind tunnel experiments to investigate how well the birds can withstand wind forces. In a 20mph headwind, they simply increase their wingbeat rate, and can remain hovering for up to an hour and a half. 

calliope hummingbird

Hummingbirds are very trainable and human-friendly, especially if you reward them with sugar water, their favourite energy hit, though the more food is laid on for them the less they’ll visit and pollinate flowers. Their beaks and long tongues are adapted to extracting nectar. The tongues themselves are an extraordinary adaptation. They’re forked at the tip, and when retracted they coil up inside their tiny heads like a garden hose. For years it was thought that the nectar was drawn out of the flowers by capillary action, like a blotter soaks up ink (showing my age), but Margaret Rubega of the University of Connecticut quickly recognised this was a crock, on first hearing of the hypothesis in the 1980s. Capillary action is a slow process, especially with more viscous liquids, but hummingbirds stick their tongues into flowers at a rate of up to 16 times a second. How their tongue works has been revealed by slow-motion photography, another example of technological advances leading to advances in knowledge – though the ingenuity of Rubega and her colleague Alejandro Rico-Guevara in working out the process played a large part. Ed Yong provides a good account here, and the more detailed original paper is also online. The hummingbird’s tongue appears to be a unique evolutionary invention, a bespoke tongue, so to speak. At its tip, where it forks, it curls up at the edges, creating two tubes. Here’s how it works, from Yong:

As the bird sticks its tongue out, it uses its beak to compress the two tubes at the tip, squeezing them flat. They momentarily stay compressed because the residual nectar inside them glues them in place. But when the tongue hits nectar, the liquid around it overwhelms whatever’s already inside. The tubes spring back to their original shape and nectar rushes into them.

The two tubes also separate from each other, giving the tongue a forked, snakelike appearance. And they unfurl, exposing a row of flaps along their long edges. It’s as if the entire tongue blooms open, like the very flowers from which it drinks.

When the bird retracts its tongue, all of these changes reverse. The tubes roll back up as their flaps curl inward, trapping nectar in the process. And because the flaps at the very tip are shorter than those further back, they curl into a shape that’s similar to an ice-cream cone; this seals the nectar in. The tongue is what Rubega calls a nectar trap. It opens up as it immerses, and closes on its way out, physically grabbing a mouthful in the process.

As Rubega and Rico-Guevara suggest in their abstract, such a unique fluid-trapping mechanism may well have biomimetic applications. As the researchers have shown, the tongue mechanism works even after the bird has died, showing that it’s in some sense independent of the bird itself, and requires none of the bird’s energy. 

It shouldn’t be too much of a surprise to find that hummingbirds have the highest metabolism of any creature (excluding insects). Apart from their record heart rate, they take around 250 breaths a minute, even resting – which they rarely do. Their oxygen intake (per gram of muscle) during flight is ten times higher than that of the most elite human athletes, and they get almost all of their energy for this hyperactive life through ingested sugars – compared to a maximum of 30% for humans. They can utilise sugars for flight within 35 minutes of consumption, which requires a very rapid oxidation rate. Though it isn’t precisely known how this rapid oxidation occurs, it does explain how they can maintain flight while feeding – they’re essentially refuelling while in flight. This raises questions, though, about long-haul flights, for example across the Gulf of Mexico – a distance of 800 kms. It appears they’re able to store fat as a fuel reserve, like other migratory birds, thus almost doubling their weight before the big journey. 

Hummingbird songs and calls are highly varied, and some are even ultrasonic – at a frequency above that of human hearing. These may be used to disturb the flight patterns of small edible insects. Most interestingly, neurological and genetic expression studies suggest that they are capable of vocal learning, something rare among birds as well as mammals. Research in this area is something I hope to explore more fully in future posts – it involves brain design, development and epigenetic factors. 

blue-throated hummingbird, a larger species – only the male has the blue throat

A few other interesting points in closing. Hummingbirds do rest at night, and when there’s no available food – they can enter a state something like hibernation, when their metabolism slows almost to a full stop. They can lose about 10% of their body weight during these states. It’s also notable that they have surprisingly long life-spans for such hyperactive creatures.  Average life-spans have been difficult to measure, but individuals of different species have been known to live for eleven or twelve years at least. 

My growing interest in birds and other creatures, especially with regard to intelligence, has inevitably led me to the load of videos available online, displaying all sorts of amazing traits, as well as profound human-animal relations. There are too many to recommend, but I would strongly suggest to any reader that they sample some of them. Watching them is somehow uplifting, and inspires a sense of hope. Life is nothing if not ingenious, even if accidentally. 

References

https://www.theatlantic.com/science/archive/2017/11/hummingbird-tongues/546992/

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

http://www.pnas.org/content/108/23/9356

Written by stewart henderson

November 15, 2018 at 10:09 am

the USA’s presidential crisis – what will they learn from it?

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it really is this crazy

The USA has a tragic problem on its hands, of its own making. It now has, as its President, a career criminal, a narcissistic demagogue, a flim flam man who’ll stop at nothing to remain in power. Within a few days, though, his power will be curtailed and, I strongly suspect, and certainly hope, US law enforcement authorities will be rounding up some of his accomplices and generally turning up the heat. Everything about Trump tells me he would be prepared to destroy as much of the country’s political edifice as he possibly can, rather than go quietly.

But it’s the political edifice itself that’s allowed Trump, who isn’t a Republican, or a Democrat, or a politician or a businessman, to take over the ship of state and steer it on a bumpy ride to nowhere. This could never have happened under the Westminster system, which pertains in Britain and Australia, two countries of which I happen to be a citizen. 

The flaws in the US Presidential system have been unwittingly exposed by Trump, and this may be the one true gift he will have bestowed on his people, just as the horrors of the great European wars of last century left the one bright legacy of over seventy years of peace in Western Europe. 

So what are these problems? Well there’s one general problem of democracy, which is shared by all democratic countries, and that’s the fact that not everyone eligible to vote is sufficiently informed or detached to use their vote to the best advantage of themselves or the nation as a whole. Many are massively influenced by what is called ‘identity politics’, because they identify with a particular sub-culture, be it ethnic, religious, job-related, or special-interest-related in a host of ways. Many simply don’t understand much about politics and are easily swayed by political promises or the promises made by those around them on behalf of politicians. The intellectual elites, the cognoscenti, have no more weight to their vote than the more or less completely clueless. 

This problem is exacerbated in the USA by the fact that, every four years, they’re asked to cast a vote essentially for one person over another. In the run-up to that vote there’s massive fund-raising and lobbying, hype (short for hyperbole), overblown promising, and circus-like razzmatazz and bells and whistles. 

The one-against-one competition is, it seems, typically American, where the ‘great man’ who saves the world by single-handedly defeating all enemies is a staple of Hollywood blockbusters. In contrast, elections in the Westminster system are more like a blend of the American mid-term and presidential elections, but with much more of the mid-term than the presidential. People essentially vote for parties – a major party of the left and of the right, together with smaller independent parties and independent members. The two major parties and the smaller parties all have leaders, of course, and they’re elected by the rest of the elected MPs of their parties. They’re the ‘captains of the team’, and they work with them in parliament. The Prime Minister, the leader of the party elected to power in general elections, is thus in a very different position from the US President, who resides in and works from the White House, surrounded by staff and officials who are appointed by himself (though more or less vetted by others) without necessarily having been elected by the public to any office of any kind in the past. These include some very influential positions indeed – the 15 members of the Presidential Cabinet including Secretary of State, Secretary of Defense, Attorney-General and Chief of Staff. The President thus heads the ‘executive branch’ of government, which is entirely separate from parliament, or congress.

Under the Westminster system there’s no such separation. The Prime Minister does get to select his cabinet, but they’re all appointed from within parliament, and all of them work within the House, or the Senate. So the PM is literally ‘primus inter pares’, first among equals, and often has to defend his or her ministers and policies in the teeth of opposition sitting across the aisle. This creates much more of a team spirit, and if the PM ‘goes rogue’, as Trump clearly has, his party can organise a no-confidence motion to oust him. Such an event obviously has major repurcussions for the nation, but they are clearly nowhere near as disastrous as the ousting of an American President. Though, arguably, the difficulties involved in ousting the President are even more disastrous. 

In watching and learning about the US political system over the past year or so, I’ve been totally astonished at the power granted to the President, and with that power comes a sense of Presidential immunity, due to his ‘indispensability’. This is virtually a recipe for demagoguery and dictatorship. The current President has clearly utilised powers that previous Presidents quite probably didn’t know they had, because they grew up within the usual ethical guidelines of the vast majority of people, regardless of background. Trump has no such guidelines, and so has sacked appointed officials without replacing them, has used pardoning powers – and will continue to do so unless ousted – without restraint, and has issued executive orders in a manipulative and detrimental fashion. He has monetised the Presidency, obstructed justice by declaring war on the FBI and justice department officials, viciously and relentlessly attacked the fourth estate, and spread myriad falsehoods with impunity.

All of this has created a kind of internal paralysis in the US, while making the country and its President both a laughing stock and a cause for grave concern worldwide. Meanwhile the success of demagoguery and ‘power’ over ethics has had its echoes in elections in Austria, Sweden and Brazil. But the USA’s political problems are unique. The two principal problems are – How do you rid yourself of a rogue president? and, How do you present this from ever happening again?

Many concerned Americans are looking to the process of impeachment as the solution. I’m writing this on the day (in Australia) of the mid-term elections, November 6, though the USA is some 11-12 hours behind us in central Australia. It seems likely that the Democrats will take control of the House and possibly the Senate, though I wouldn’t bet on it – I usually get these things wrong. But impeachment is a political process and therefore highly partisan in a nation that has become partisan perhaps to the point of extreme violence. Impeachment doesn’t exist in the Westminster system, because there is clearly no need for it.

For a Prime Minister, under the Westminster system, to ‘successfully’ go rogue, as the US President has, he would have to carry the whole of his party with him, or a substantial majority, as the party system and party loyalty are deeply entrenched in the polity. A no-confidence motion in the Prime Minister can be put up at any time during parliamentary sessions, either from within the PM’s party or from the opposition benches. It’s easier for the President to become a ‘one-man band’ because he’s entirely cut off from congress. I don’t know if Trump has ever entered congress. There seems no reason for him to do so. This complete disconnection from what is is supposedly his own party and government is, I think, disastrous. 

The massive power of the President – veto powers, pardoning powers, executive orders, and apparent, if limited, immunity from prosecution – is no small problem for a country that is the most economically and militarily powerful in the world.  Rachel Maddow of NBC has highlighted the problem of prosecuting the President. If he is charged and placed in custody or let out on bail, does he still have presidential authority? If not, who does? This would not be a problem under the Westminster system – the Deputy PM would step up, as s/he does when the PM is overseas. And if the matter were serious enough, that deputy, or another senior cabinet minister, would take over the PM’s role permanently. And there would be no hesitancy, under that system, to arrest and detain. Why should there be? The law should treat all offenders in precisely the same way.

In the US there seems to be a lot of confusion on these matters. Many consider the President ‘too important’ to be charged with a crime while in office. This is truly ridiculous. If you have allowed one person to be so important within your political system as to be above the law, for even a second, then your political system sucks, to put it mildly. 

Another bizarre anomaly of the US system is this ‘hanging back’ by the federal authorities, in terms of subpoenas and indictments, during pre-election periods. This, it seems to me, is an interference, by a kind of stealth, of the judiciary by the political sphere. Where did this ridiculous idea come from? It seems abundantly clear to me that when investigating potential felonies of any kind, the political background should play no part whatsoever. Once investigators have ‘all their ducks in a row’, as Americans like to say, that’s when prosecutions should begin. I’ve no idea right now what will happen to Trump after these elections, but he has already been clearly implicated in campaign finance violations via his criminal fixer, so prosecutions should have occurred already. To not institute criminal proceedings when everything is set to do so, because of some election or other – that constitutes political interference. Am I missing something here?  

Assuming that Trump is indicted after these elections (though what I’ve heard is that the Mueller will only issue a report to congress, even if it includes indictable offences, which makes my head spin with its unutterable stupidity and dereliction of duty), is it likely that Trump will give himself up to authorities? Trump is a career criminal who has never spent any time in jail, though his tax crimes and various scams should have seen him incarcerated for much of his adult life. It’s hard to know what he’ll do when cornered, but I can’t imagine him giving himself up to authorities. The real crisis is about to hit the fan, so to speak. It will get very very bumpy over the next few months, no matter what the election result. 

The other major question is – what will Americans learn from the Trump disaster? Will they reform their political system? With their jingoistic pride, I don’t hold out too much hope. My guess is that there will be some reform around the edges – the emoluments clause might be ‘promoted’ to something more than a mere clause, for example – but their beloved but outdated Constitution will remain largely untouched, and they’ll still keep their POTUS in splendid isolation, a law unto himself and a potential threat to their nation and the outside world. But then, as some dipshit has often said, we’ll have to wait and see. 

 

Written by stewart henderson

November 6, 2018 at 8:52 pm

bird smarts and theory of mind

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human brain compared to that of a zebra finch, I think

I like birds a lot – how could you not? I particularly like their brains, which considering their ‘beautiful plumage’, their grace in flight, their songs, their treatment of mates and offspring and their dinosaur history, is quite a big call. Not that I’ve ever seen or examined a bird’s brain, but I’ve seen and heard of  some gobsmacking behaviour from some species, so I thought I might check out what’s known about their grey-white matter.

As with so many research fields, there’s been a surge in research into bird brains, and I’ve not heard the term bird-brain used as an insult in recent times. Still, when we think of bird intelligence, we tend to anthropomorphise, to compare them with us – do they play, do they use language or tools, do they recognise us individually, can they solve the same sorts of problems we can? That’s understandable enough, but in studying bird brains we should be just as thoughtful about the differences as the similarities.

The birds that have stood out for us so far are corvids – ravens, crows, jays and magpies, though many parrots such as the sadly endangered kea of New Zealand have also caught researchers’ attention. So how do these small-brained creatures manage to do the things that so impress us? Well for a start it may be more a matter of numbers than actual size (and it should be noted that birds have the largest brain to body ratio of any creature). Some research published in July 2016, which received a lot of media attention, found that bird brains pack neurons more densely than other animals. It was previously thought that neuron density didn’t vary much between species, but it’s now becoming clear this isn’t so, and actual brain size isn’t such a reliable guide to intelligence. But bird brains are really small compared to those of primates, so there must surely be other differences besides density.

But the 2016 research, which featured a revolutionary method for sampling brain tissue and making neuron counts, found that, in fact, a parrot brain contained as many neurons as some mid-sized primates. However, it’s also true that a bird’s brain is structurally different. Unsurprisingly, in the past, bird brains were thought of as primitive, and were classified as such, probably because they’re far removed from us on the evolutionary bush. Anthropomorphism again – understandably we used to feel that the only really intelligent creatures apart from us were those most closely related to us, but in recent decades we’ve learned that cetaceans, octopuses, elephants and birds, none of which are close to us  evolutionarily, are highly intelligent creatures. And they’re not all mammals, and in the case of the octopus, not even vertebrates. This is quite exciting for our understanding of intelligent life forms – they can have a multitude of ‘brain plans’.

The first important bird brain anatomist was the 19th century German naturalist Ludwig Edinger, whose work was so influential that it provided the orthodox view until a few decades ago. Noting the very different structure of the bird brain, Edinger understandably assumed they couldn’t be as smart as mammals, and being one of the first to name brain structures in birds, he assigned names such as paleostriatum, suggesting a very basic region involving instinctual and motor activity. Basically, he assumed birds lacked a neocortex altogether. However, we now know that the bird brain evolved from the pallium rather than the striatum, and in 2005 it was agreed that an overhaul of bird brain nomenclature was required. All part of our more informed and respectful approach to these wondrous creatures.

National Geographic, in combination with other interested organisations, has declared 2018 the Year of the Bird, and has some fascinating pieces on bird behaviour on its website. That’s where I learned that, according to one researcher, birds’ brains are more distributed ‘like a pizza’, whereas the mammalian brain is more layered. However, the wiring that underlies long-term memory in birds (and they clearly have impressive long-term memory) and decision-making is similar to that in mammals. 

Here are just a few of the extraordinary behaviours discovered. Green-rumped parrotlets of South America use calls as names for their chicks. Male palm cockatoos of New Guinea court females not only with calls but by drumming on hollow trees with twigs and seedpods – arguably a form of music. Goffin’s cockatoos, from Indonesia, make and use tools in captivity even though they’ve never been seen to do so in the wild. They’re also expert at opening locks. The National Geographic video ‘Beak and Brain: genius birds down under’ compares the kea of New Zealand’s South Island to the New Caledonian crow as problems solvers tasked with overcoming a variety of obstacles to obtain their favourite treats. It makes for riveting viewing. Other videos online show crows creating hooks on sticks and using them to pull food out of holes. 

Another video, involving experiments with jackdaws by Princess Auguste of Bavaria (really), a behavioural scientist, shows that these birds are much influenced by the gaze of humans, and can be directed to act simply by the gaze of a human they have bonded with. They also appear to know when they’re not being watched, and can act more boldly in such circumstances. All of this raises obvious questions, voiced by Auguste in the video. How do jackdaws think? How is it similar to the way we think? Do they recognise intentions? Do they have a theory of mind?

This theory of mind issue comes up with a lot of birds, and other animals. It refers to whether and to what extent a creature has the ability to attribute any or all of the variety of possible mental states to itself and/or others. The question of an avian theory of mind was explored in a study entitled ‘ravens attribute visual access to unseen competitors’. In describing their experiment, the authors highlight what they see – or what skeptics see – as a problem with much experimental work that tests for theory of mind in other species. This is the question – as I understand it – of whether the bird or animal actually ‘sees’ or reads what conspecifics are thinking, or is simply following particular observable cues. It was a complex experiment involving caching (hiding a store of food for later consumption, a common raven behaviour), peepholes that were either open or closed, and inference (by the researchers) from observed behaviour to either ‘minimal’ or ‘full-blown’ Theory of Mind. As a dilettante I found much of the discussion and analysis beyond me, but I found these remarks interesting:

In conclusion, the current experiment, together with the other recent studies on chimpanzees11,12, provides strong evidence against the skeptical hypothesis that the social cognition of nonhuman animals is limited to behaviour-reading. Peephole designs can allow researchers to overcome the confound of gaze cues, but further experimental work is needed to determine the specific limits of ravens and other animals—including humans—on such tasks.

In my general reading on these matters I’ve definitely found something like a rift between the skeptics on the behaviour of higher primates, dolphins and other ‘smart’ creatures, and those who have pushed, sometimes naively, other-life smarts with regard to ‘language’, memory and emotional intelligence. What I think needs to be kept clearly in mind is that in examining intelligence, or brain power or whatever, human intelligence may be only one of a possible infinity of gold standards. Is Theory of Mind itself an anthropomorphic concept, or one that lends itself too easily to anthropomorphic thinking? 

Meanwhile, experimentation and investigation of the neurological underpinnings of bird behaviour will continue, and I’ll be watching for the results. Just about to embark on Jim Robbins’ book The wonder of birds, and I hope to learn more especially about bird neurology in the future, and how it relates to birdsong. That’s a whole other issue.

Written by stewart henderson

November 2, 2018 at 9:40 am

another look at free will, with thanks to Robert Sapolsky

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Ah poor old Aynnie – from guru to laughing stock within a couple of gens

Having recently had a brief conversation about free will, I’ve decided to look at the matter again. Fact is, it’s been playing on my mind. I know this is a very old chestnut in philosophy, renewed somewhat by neurologists recently, and I know that far more informed minds than mine have devoted oodles of time and energy to it, but my conversation was with someone with no philosophical or neurological background who simply found the idea of our having no free will, no autonomy, no ‘say’ whatever in our lives, frankly ludicrous. Free will, after all, was what made our lives worth living. It gives us our dignity, our self-respect, our pride in our achievements, our sense of shame or disappointment at having made bad or unworthy decisions. To deny us our free will would deny us….  far far too much.

My previous piece on the matter might be worth a look (having just reread it, it’s not bad), but it seems to me the conundrum can be made clear by thinking in two intuitively obvious but entirely contradictory ways. First, of course we have free will, which we demonstrate with a thousand voluntary decisions made every day – what to wear, what to eat, what to watch, what to read, whether to disagree or hold our tongue, whether to turn right or left in our daily walk, etc etc. Second, of course we don’t have free will – student A can’t learn English as quickly and effectively as student B, no matter how well you teach her; this student has a natural ability to excel at every sport, that one is eternally clumsy and uncoordinated; this girl is shy and withdrawn, that one’s a noisy show-off, etc etc.

The first way of thinking comes largely from self-observation, the second comes largely from observing others (if only others were as free to be like us as we are). And it seems to me that most relationship breakdowns come from 1) not allowing the other to be ‘free’ to be themselves, or 2) not recognising the other’s lack of freedom to change. Take your pick.

So I’ve just read Robert Sapolsky’s take on free will in his book Behave, and it strengthens me in my ‘free will is a myth’ conviction. Sapolsky somewhat mocks the free will advocates with the notion of an uncaused homunculus inside the brain that does the deciding with more or less good sense. The point is that ‘compatibilism’ can’t possibly make sense. How do you sensibly define ‘free will’ within a determinist framework? Is this compatibilism just a product of the eternal complexity of the human brain? We can’t tease out the chain of causal events, therefore free will? So if at some future date we were able to tease out those connections, free will would evaporate? As Sapolsky points out, we are much further along at understanding the parts of the prefrontal cortex and the neuronal pathways into and out of it, and research increases exponentially. Far enough along to realise how extraordinarily far we have to go. 

One way of thinking of the absurdity of the self-deciding self is to wonder when this decider evolved. Is it in dogs? Is it in mosquitos? The probable response would be that dogs have a partial or diminished free will, mosquitos much less so, if at all. As if free will was an epiphenomen of complexity. But complexity is just complexity, there seems no point in adding free will to it. 

But perhaps we should take a look at the best arguments we can find for compatibilism or any other position that advocates free will. Joachim Krueger presents five arguments on the Psychology Today website, though he’s not convinced by any of them. The second argument relates to consciousness (a fuzzy concept avoided by most neurologists I’ve read) and volition, a tricky concept that Krueger defines as ‘will’ but not free will. Yes, there are decisions we make, which we may weigh up in our minds, to take an overseas holiday or spend a day at the beach, and they are entirely voluntary, not externally coerced – at least to our minds. However, that doesn’t make them free, outside the causal chain. But presumably compatibilists will agree – they are wedded to determinism after all. So they must have to define freedom in a different way. I’ve yet to find any definition that works for the compatibilist.

There’s also a whiff of desperation in trying to connect free will with quantum indeterminacy, as some have done. Having read Life at the edge, by Jim Al-Khalili and Johnjoe McFadden, which examines the possibilities of quantum effects at the biological level, I’m certainly open to the science on this, but I can’t see how it would apply at the macro level of human decision-making. And this macro level is generally far more ‘unconscious’ than we have previously believed, which is another way of saying that, with the growth of neurology (and my previous mention of exponential growth in this field is no exaggeration), the mapping of neurological activity, the research into neurotransmission and general brain chemistry, the concept of ‘consciousness’ has largely been ignored, perhaps because it resembles too much the homunculus that Sapolsky mocks. 

As Sapolsky quite urgently points out, this question of free will and individual responsibility is far from being the fun and almost frolicsome philosophical conundrum that some have seemed to suggest. It has major implications for the law, and for crime and punishment. For example, there are legal discussions in the USA, one of the few ‘civilised’ nations that still execute people, as to the IQ level above which you’re smart enough to be executed, and how that IQ is to be measured. This legal and semi-neurological issue affects a significant percentage of those on death row. A significant percentage of the same people have been shown to have damage to the prefrontal cortex. How much damage? How did this affect the commission of the crime? Neurologists may not be able to answer this question today, but future neurologists might. 

So, for me, the central issue in the free will debate is the term ‘free’. Let’s look at how Marvin Edwards describes it in his blog post ‘Free will skepticism: an incoherent notion’. I’ve had a bit of a to-and-fro with Marvin – check out the comments section on my previous post on the topic, referenced below. His definition is very basic. For a will, or perhaps I should say a decision, to be free it has to be void of ‘undue influences’. That’s it. And yet he’s an out and out determinist, agreeing that if we could account for all the ‘influences’, or causal operants, affecting a person’s decision, we could perfectly predict that decision in advance. So it is obvious to Marvin that free will and determinism are perfectly compatible.

That’s it, I say again. That’s the entire substance of the argument. It all hangs on this idea of ‘undue influence’, an idea apparently taken from standard philosophical definitions of free will. Presumably a ‘due influence’ is one that comes from ‘the self’ and so is ‘free’. But this is an incoherent notion, to borrow Marvin’s phrase. Again it runs up against Sapolsky’s homunculus, an uncaused decider living inside the brain, aka ‘the self’. Here’s what Sapolsky has to say about the kind of compatibilism Marvin is advocating for, which he (Sapolsky) calls ‘mitigated free will’, a term taken from his colleague Joshua Greene. It’s a long quote, but well worth transcribing, as it captures my own skepticism as exactly as anything I’ve read:

Here’s how I’ve always pictured mitigated free will:

There’s the brain – neurons, synapses, neurotransmitters, receptors, brain-specific transcription factors, epigenetic effects, gene transpositions during neurogenesis. Aspects of brain function can be influenced by someone’s prenatal environment, genes, and hormones, whether their parents were authoritarian or their culture egalitarian, whether they witnessed violence in childhood, when they had breakfast. It’s the whole shebang, all of this book.

And then, separate from that, in a concrete bunker tucked away in the brain, sits a little man (or woman, or agendered individual), a homunculus at a control panel. The homunculus is made of a mixture of nanochips, old vacuum tubes, crinkly ancient parchment, stalactites of your mother’s admonishing voice, streaks of brimstone, rivets made out of gumption. In other words, not squishy biological brain yuck.

And the homunculus sits there controlling behaviour. There are some things outside its purview – seizures blow the homunculus’s fuses, requiring it to reboot the system and check for damaged files. Same with alcohol, Alzheimer’s disease, a severed spinal cord, hypoglycaemic shock. 

There are domains where the homunculus and that biology stuff have worked out a détente – for example, biology is usually automatically regulating your respiration, unless you must take a deep breath before singing an aria, in which case the homunculus briefly overrides the automatic pilot.

But other than that, the homunculus makes decisions. Sure, it takes careful note of all the inputs and information from the brain, checks your hormone levels, skims the neurobiology journals, takes it all under advisement, and then, after reflecting and deliberating, decides what you do. A homunculus in your brain, but not of it, operating independently of the material rules of the universe that constitute modern science.

This captures perfectly, to me, the dilemma of those sorts of compatibilists who insist on determinism but. They seem more than reluctant to recognise the implications of that determinist commitment. It’s an amusing description – I love the bit about the aria – But it seems to me just right. As to the implications for our cherished sense of freedom, we can at least reflect that it has ever been thus, and it hasn’t stopped us thriving in our selfish, selfless ways. But as to the implications for those of us less fortunate in the forces that have moved us since childhood and before, that’s another story.

References

https://ussromantics.com/2018/05/15/is-free-will-a-thing-apparently-not/

R Sapolsky, Behave: the biology of humans at our best and worst, Bodley Head 2017. Note especially Chapter 16, ‘Biology, the criminal justice system and free will’. 

https://plato.stanford.edu/entries/compatibilism/#FreWil

https://www.psychologytoday.com/au/blog/one-among-many/201803/five-arguments-free-will

https://www.theatlantic.com/notes/2016/06/free-will-exists-and-is-measurable/486551/

Written by stewart henderson

October 27, 2018 at 1:25 pm

why I’m not a conservative

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Probably better to read this highly recommended book than my article, but you’re welcome to do both

There are many ways of answering the above question. I might state the obvious – conservatives tend to be stodgy, boring, backward-facing selfish naysayers with a limited social conscience and little interest in, if not an outright fear of, scientific and technological development.  End of story.

But of course, that can’t be the whole story. We’re not as free to develop our own views as we think. I’m a product of a particular environment, a very working-class environment, though very bookish within the family. The recent Kavanaugh kerfuffle reminds me of my rough and ready high school days, though I was more often a victim than a perp. All through high school I was the smallest and probably lightest kid in my class, male or female, so I was the target of pranks, mostly ‘good-natured’. For example, on two occasions I was held out upside-down by the legs over the first-floor balustrade by my fun-loving schoolmates. Had they lost their collective grip, I suppose I would’ve dropped head-first to probable death. Yet, though I’m sure my heart-rate was well up at the time, I had a pretty strong faith in my friends – all boys of course – and their benign intentions. I never lost any sleep over it afterwards. 

I’m not suggesting this was working-class hijinx – think of Eton and Harrow ragging, etc – but there was more, including stuff I’m far from proud of, as I strove to fit in with the anti-intellectual and often nihilistically violent environment around me. The quality of teaching was pretty poor, our headmaster was an outright fascist, and I was happy to be a high school drop-out at fifteen. I got occasional assembly-line work, and my spare time was spent either failing to ingratiate myself with a gang of local vandals, or reading Jane Austen or encyclopaedia entries on Isaac Newton, etc. Not to mention wanking myself silly to fantasies of any local beauty I happened to clap my eyes on. Another great solace and opening to a wider world was the wordsmith musical artists of the early seventies I obsessed over, such as Dylan, Cohen and Bowie. 

So what has this to do with my politics? Well, the region of my childhood and youth was, and still is, one of the safest Labor electorates in the country (Labor, for international readers, is the party of the left here in Australia, as it is in Britain). I can’t imagine it ever going the way of the conservatives. In Australia, the urban/suburban working-class tend to vote left, while the rural working-class tend to vote right. It’s perhaps different from the USA where the working-class in general tend to vote right (though this seems to happen here in some parts, notably Queensland). This kind of pro-union us-and-them mentality, an atmosphere of both togetherness and despair, was what I breathed in as I wandered lonely as a cloud through the streets of my town. I engaged with others in petty theft and pointless vandalism, got caught and was placed on a bond, and felt self-servingly that the law was the principle weapon of the rich to beat down the poor.

In the early seventies a downturn in the economy hit our region particularly hard, and I felt it in the air of neglect and dilapidation, the family breakdowns, the beginnings of generational unemployment. I saw a neighbourhood of victims, unable to climb out of their situation, as if they’d been sold a pup and didn’t know quite who to blame. 

I didn’t hang around, I moved to a bigger smoke, and a more variegated, bohemian-student world. My problems of ‘fitting in’ didn’t exactly go away, but I was becoming more reconciled to my ‘loner’ identity. And of course I was educating myself more about politics, economics and history. But always I’ve been concerned about the most vulnerable, the least advantaged, those who ‘lucked out’ in our society. This goes with my views on free will, and on nationalism. We don’t get to choose our parentage, or the where and when of our birth. I politely decline to sing songs about how wonderful and unique ‘my’ country is, because I know that if I was born in another country on the other side of the world I’d be pressured to sing songs about its splendour and specialness. I feel lucky to be a citizen of two peaceful and developed countries, just as I feel lucky to have been born a human rather than a mosquito. I feel lucky to be alive when all this new knowledge is being uncovered, in astronomy, in neurology, in palaeontology and so much else, though I feel unlucky to have been born in 1956 rather than 1996, or even later.

But the implications of this matter of luck seem to me enormous, and they’re essential to my political views. For example, they largely define my views on education, health, welfare, immigration and the justice system. To me, one of the major roles of a political state is to do its best to mitigate, for its members, the destructive effects of bad luck. 

Broadly speaking, the history of politics has ever been the battle between the left and the right – patricians v plebeians, socialists v libertarians, progressives v traditionalists, Labor v Conservative, Republicans v Democrats, with independents ranged across the political spectrum. Those who want to do more for their people v those who want to let people do for themselves, and various other polarities. Of course, not all these categories are the same on each side of the v sign, which raises all sorts of questions. Where does business and capitalism fit in? What about the environmental movement? What about globalism and its detractors? 

My views on many of these matters aren’t well-formulated – or I should say, in a more self-boosting way, they’re not hard and fast. However, the application of a basic rule of thumb – ‘try to reduce the effect of bad luck’, is, I think, a useful starting point. For example, a taxation system that tries to reduce disadvantage in terms of education and healthcare is important, but one that heavily reduces incentives for businesses and entrepreneurs may ultimately affect productivity and the wealth from which taxation can be drawn. At the same time it’s dangerous to fall for the line of the ‘haves’, that tax breaks for the ‘deserving rich’ will ultimately benefit all through greater employment and opportunity. The rich, I’ve noticed, like very much to keep it in the ‘family’ – gated communities being the most in-your-face symbol of the trickle-across effect. 

Governing isn’t easy, especially under the constant scrutiny of vested interests – and that means everyone. One of the major difficulties I’ve noticed is that some scrutineers, e.g. the Rupert Murdochs of this world – are vastly mote powerful than others, so money and influence are always at play – and those in most need are always those who have least influence. It’s easy to lose sight of that – though many conservatives aren’t worried about that, they often see their rich supporters as a natural elite, and the strengthening of that elite as their natural duty in government.

I know this is a bitsy sort of essay – I don’t have an ideology as such, but I do have some strong views, against ideology and for pragmatism, against adversarialism and for collaboration, against realpolitik and nationalism and for the more voiceless and lucked out members of our species – often the victims of realpolitik. I’m also for the progress of science and technology against the fearful or dismissive or wilfully ignorant naysayers. I know I’ve just contradicted myself, seemingly, in speaking for  collaboration and then couching issues in for/against terms, but of course you must have core beliefs to bring to a negotiation, which you can present for consideration while considering and questioning the views of the opposition, as they question yours. And those who aren’t prepared to listen – and I can name quite a few – shouldn’t be allowed at the table. 

I like the approach of Aristotle – first you work out your ethics (the particular or individual) then apply it to politics, the general. Of course, the first thing to note, as you try to work out what you should do, is that it must be in relation to others, the general. Without that ‘general’, which is life itself, not just humanity, as natural selection has taught us, we individuals wouldn’t be here. So the relationship between the individual and the general is necessarily dialectical, but it starts off with that personal question. And there is always that tension, for progressives – those who believe in pushing forward not yearning backward – between that forward movement and responsibility for the luckless strugglers, those so easily left behind. It makes for a very difficult task for those well-meaning politicians I admire. Scientific, technological and intellectual progress is happening at a more rapid clip than ever before, but it’s spreading the spectrum ever wider, not just between the haves and have nots, but between attitudes towards and against that progress, between adoring enthusiasm and hate-filled fear. 

So. I’m not a conservative. I want to embrace the future, to help make it happen. I want it to improve the lot of the majority, especially of those whose lot needs most improving, so that they can share in enthusiasm for the future. I want women to rule the majority of the world, because I believe this would improve humanity, and the world. I want to avoid warfare as much as humanly possible, because the costs are always borne by those who can least afford them. I want to challenge the power of self-serving elites, and to shake their complacency. I want people to think about and recognise the consequences of their actions – especially those with power over others. The future will happen, and we can choose to face forward, and put our hands to those shaky and complicated controls, or to look away and pretend it’s not happening. It’s not much of a choice really. 

Written by stewart henderson

September 23, 2018 at 2:25 pm

the movements of the Earth, the ecliptic, the celestial sphere…

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Why does the Earth spin? Initial conditions plus Newton’s first law is the basic explanation. And from these it should be easy to guess that it’s slowing down as tiny but inexorable forces act upon it, and it will continue to do so unless something unforeseeable happens. The tidal friction caused by the moon, which itself is decreasing over time (or at least I assume so, since the moon is spiralling away from us) is the Earth’s principal brake. Some say that Earth has been gradually slowing down since the last great collision, which created the moon, and which left the planet spinning full circle every six hours, but I think that’s still speculative.

Anyway, we don’t just rotate (in an anti-clockwise direction), we revolve (anti-clockwise) around the sun on a plane tilted at 23.4 degrees from our spin – that’s tilted from the perpendicular. But why? And there’s this thing called precession, right? Spin a top, as I did as a kid, and the most successful spin will have the least precession – the smallest circle (actually a cone) around which the axis of rotation wobbles, but as the top slows that cone will widen until all falls in a heap. In the Earth’s case, it’s most commonly called the precession of the equinoxes, or ‘the wobble’ (maybe).

So the Earth moves in mysterious ways, and I’ve barely begun. It orbits the sun – why? Its orbit is elliptical – why? Its rotational and revolutionary speed vary – why? And what about other movements – the solar system, the galaxy, the universe?

A cool video I’ve been watching tells me something I’d never known or thought of before. We’re all on meridian lines, which pass through us in a north-south direction, from the north pole to the south pole. Lines of longitude. When the sun is at its highest point in the sky, at noon, it’s aligned perfectly with our meridian. The shadow it casts, our shadow, thus points precisely to the north or south pole, depending on the sun’s position north or south of ‘directly overhead’. If the sun is directly overhead, congratulations, you’re on the sub-solar point, and your shadow will disappear beneath your feet, so to speak. Right now the sub-solar point is a circular area in the Atlantic, a little north of the equator, and just touching land in west Africa. I doubt if we ever experience it here in Australia, as it seems to hang close to the equator.

The point to make here is one about time. As there’s a meridian line for just about everyone, it follows that everyone on a different meridian is experiencing a different time. Noon, or any other time, isn’t the same for everyone – but that’s massively inconvenient, so we’ve regularised time via zones, so we can do our business.

Looking again at our rotation, we might think we have it nailed at very close to 24 hours per full rotation, but not quite, for all is relative. The sun, for example, has its movements too, as does everything else. We’ve found that, measured from a distant star, one meridian completes a revolution in 23.9 hours, also known as a sidereal day. Our calendars, though, are based on the solar day. As the Earth turns, it moves forward in its revolution around the sun. So by the time it has turned 360 degrees it needs to spin a little more for the same spot to be facing the sun as was the case 24 hours before. That slightly greater than 360 degree turn is what we call the solar day. From our perspective it seems like an exact 360-degree turn because we’re facing the sun again, exactly as the day before. Or so it seems.

We revolve around the sun in an ellipse. Or not precisely around the sun. Kepler’s first law of planetary motion, presented to the world without fanfare in 1609, had it that all the planets traced an elliptical orbit around a focal line, with the sun as one of its end-points, or foci. And while we’re at it, let’s look at Kepler’s three laws and how they were arrived at. The second law, presented in the same year, states that ‘a line segment joining a planet to the sun will sweep out an equal area over an equal time interval’, and the third law, announced to a largely indifferent world in 1618, is perhaps less linguistically elegant, or at any rate simple: ‘The square of the orbital period of a planet is proportional to the cube of the semi-major axis of its orbit.’ I ripped this from Wikipedia, the greatest gift to all dilettantes and autodidacts ever developed.

Kepler’s laws improved on those of Copernicus, but of course they accepted Copernicus’ heliocentric system as the basis. All Kepler really added was the eccentricity of planetary orbits, a minor detail really, but certainly an improvement. His laws weren’t presented as such at the time: they weren’t described as laws until Voltaire’s  publication of Eléments de la philosophie de Newton, no doubt largely the work of his intellectual superior, Emilie du Chatelet.

So, the first two laws. Kepler was given access to some of the detailed astronomical data of his employer Tycho Brahe, who asked him to calculate precisely the orbit of Mars. Tycho apparently withheld the bulk of his observations from Kepler, because he suspected him of being one of those upstart heliocentrists. Kepler wanted, for largely mystical reasons, to define the Mars orbit as a perfect circle, but after years of trying the calculations wouldn’t work out. What he did discover was that, although the orbital path wasn’t circular – the sun was sometimes further away, sometimes closer –  if you drew a line from Mars (or any other planet, including Earth) to the sun, and then another line, say exactly six days later, the triangle created always had the same area, no matter where you were in the orbit. For this to happen, the planet must be moving faster nearer the sun than when further from the sun. This was Kepler’s second law, which helped him to calculate the first. The planets’ orbits appeared to be elliptical. If the sun was offset from the centre of the planetary orbits, but still obviously essential to those orbits, then the offset could be calculated precisely such that all the planetary orbits fitted. And so it was. Most astronomers consider this to be his greatest contribution.

Kepler’s third law, with its interesting mathematical basis, provided the greatest inspiration to Newton:

The square of the orbital period of a planet is proportional to the cube of the semi-major axis of its orbit.

P2 = a3

I rarely do maths here, but surely this one’s simple enough even for me! The orbital period (p) of a planet is the time it takes to make a complete revolution around the sun. Note that it’s a measure of time, not distance. The semi-major axis of an ellipse is half its longest diameter. In the special case of a circle, it would be the radius. This law enables us, apparently, to determine the distance of planets from the sun, though it appears to entangle time and space. Generally these distances are given in relative terms. with the Earth’s distance from the sun given the value 1 AU (astronomical unit). By that reckoning, the outermost planet, Neptune, has a value of 30.06 AU, approximately, according to one site providing such data. Similarly, we reckon the orbital period in Earth years. Neptune’s orbital period is 164.79 years. So, for Neptune, 164.79² = 30.0611³. Try it on a calculator and you’ll find it doesn’t quite work out, but this may be due to eccentricity of orbits, in time and space. Other sites have different figures. The Kepler equation seems to capture the pattern rather than the precise detail. It’s probable that the publication of logarithmic tables between Kepler’s calculation of the first two laws and the third was vital.

I’m of course no expert on any of this – go to more reputable sites for a more complete story, though you’ll probably find what I found – a fair amount of interesting confusion.

I’ll finish with the ecliptic. The Earth’s orbit sketches out an elliptical plane, which we call the ecliptic. Then again, the ecliptic is also described as the apparent motion of the sun in the sky with respect to the fixed stars – not to be confused with the apparent daily movement caused by Earth’s rotation. In fact Wikipedia describes the ecliptic as ‘the mean plane in the sky that the sun follows in the course of a year’, and Wikipedia is always way more right than I am in these matters, but it’s confusing. The plane can be visualised as stretching out into space, way beyond the actual orbit around the sun and bounded within a celestial sphere, with a ‘celestial equator’, on the same plane as Earth’s equator, also marking a circular section of the sphere at 23.4° from the ecliptic. The north-south celestial axis, an extension of Earth’s axis to the celestial sphere, is again at an angle of 23.4°, on average, from the north-south ecliptic axis, which runs perpendicular to the ecliptic plane.

There’s more, but I’ll stop at this. The ecliptic plane for Earth is an average, as there are always perturbations. The other planets don’t follow this ecliptic precisely, but they’re not too far away, probably as a result of uniforming forces at the creation of the solar system.

 

Written by stewart henderson

September 8, 2018 at 9:43 pm