Wednesday: Hili dialogue, Marsh Farm rush hour and some US politics

November 6, 2019 • 5:32 am

by Matthew Cobb

In Poland, Hili is giving feedback:

Hili: Collective thinking for the easier solving of difficult problems.
A: You know how highly I value your critical remarks.
Hili: Zbiorowy namysł pozwala łatwiej rozwiązywać trudne problemy.
Ja: Wiesz jak bardzo cenię wszystkie twoje krytyczne uwagi.
.At Marsh Farm, the animals are particularly excited to leave the barn:

Chelicerate 1, Marsupial 0

Another chelicerate, which also goes by the name of a vinegaroon, for reasons explained in the tweet. This one is rather cross.

More arthropod grimness, but amazing nonetheless:

Two avian tweets:

Two great illusions. Watch carefully to see how your brain works to make sense of what it is seeing. You should feel the flip:

Quiz: what is James O’Donoghue getting at here?

Finally, a message from The Boss, out on the high seas heading for Antarctica:

The New York Times reports that, after yesterday’s elections, both houses of the Virginia legislature are now Democratic (as is the governorship), so the state is now Demorcatic. And it looks as if the Democratic contender for governor won narrowly in Kentucky, too. This is good news, and, I hope, a harbinger of next year’s Presidential election.

JAC addendum: Our Secret Duck Farmer reports a record number of ducks at the pond this morning: 25 mallards, all hungry as hell. Perhaps they’re fueling up for the Big Migration; at least I hope so. The weather is supposed to be a bit above freezing this week, and I hope that inspires them to head south.

43 thoughts on “Wednesday: Hili dialogue, Marsh Farm rush hour and some US politics

    1. The smile of the day news (from the WaPo):

      “Cyclist who flipped off Trump wins county supervisor seat representing his golf club”

  1. The good news in yesterday’s elections was going to be my comment today as well. Not only going all blue in Virginia and a democratic governor in Kentucky, we also got a democrat for Mayor in Wichita. Things are looking up.

  2. Re the James Donoghue tweet, I think it’s the orientation of the respective planets’ spin axes.
    Uranus’ spin axis is close to the orbital plane, whereas Venus spins (slowly) in the opposite direction to its orbital rotation.

    1. I didn’t know Venus had a reverse spin. Is there an explanation for it? It seems, if our understanding of the formation of the Solar System correct, that the initial spin would have been the same as other planets.

      1. If I remember my astronomy correctly, it’s expected that an impact event, or several, are responsible for its retrograde spin.

        1. Also, because Venus is so close to the sun, its original rotation would have been slowed to tidal lock, so it wouldn’t take enormous force to nudge it the other way.

          Another theory is that it flipped on its axis. Not sure how that could happen.

            1. Good link. Hypotheses for retrograde rotation:
              1. “spin changes caused by planetary perturbations and tidal effects on its dense atmosphere”
              2. There is evidence for a huge impact event billions of years ago.

              From the article, Venus fun facts:

              “Because its rotation is so slow, Venus is very close to spherical”, meaning it does not bulge around the equator.
              “Venus’s equator rotates at 6.52 km/h, whereas Earth’s rotates at 1,674.4 km/h”
              “on Venus, the Sun would rise in the west and set in the east”
              “In 2016, NASA studied a rover designed to survive for an extended time in Venus’s environmental conditions (500 degrees C). It would be controlled by a mechanical computer and driven by wind power”

          1. Also, because Venus is so close to the sun, its original rotation would have been slowed to tidal lock,

            Those forces certainly exist (a guy called George Darwin did the maths in the 1880s-90s ; you may have heard of his biologist father) but they’re steeply dependent on the spacing of planet and star. Satellite and primary, to be honest – it doesn’t really matter the absolute sizes of the bodies, just their relative sizes. In order to stop Venus’ rotation, the damping forces would need something closer to the age of the universe to do it, not the age of the solar system (about 1/3 of the age of the universe).
            It is hard to calculate such things with precision – a major factor is the drag between the atmosphere and the solid part of the satellite. While the viscosity of gasses at low pressures is fairly amenable to experiment, it’s only recently that we’ve had anything like a good elevation model of Venus’ surface under the clouds (merci, Magellan!). And the arguments about WTF is happening on Venus tectonically are live. So back-calculating to work out it’s rotation period in the past … thorny.
            The Earth’s Moon is relatively much closer to Earth then Venus is to the Sun (Moon orbit/ Earth radius ~=60 ; Venus orbit / Sun radius ~=155) ; that in itself should suggest that they’re in very different dynamical regimes.

            The tidal lock of the Moon to the Earth appears to date from before the solidification of the “magma ocean” phase of the Moon’s development. There is about a 60km offset between the centre-of-figure of the Moon and the centre-of-mass, which acts to provide a restoring moment to keep the Moon’s rotation locked tidally to the Earth-Moon line. Exactly when this developed … I don’t think anyone has tried to tie the date down, but on mass considerations alone (the Moon masses about 1% of the Earth), it’s magma ocean would have solidified from the surface down long before the Earth’s. The date that the Earth acquired a solid(-ish) crust is away back in the Hadean. The presence of zircon grains with dates back in the 4.1+ gigayear range and oxygen stable isotope ratios indicating that they developed in the presence of liquid water. It is hard to do that without some sort of a solid crust.

            That the Moon’s near-side and far side have different cratering histories back to the “late heavy bombardment” period (about 3.8 gigayears) is an argument that the tidal lock dates back into the Hadean too.

      2. It seems, if our understanding of the formation of the Solar System correct, that the initial spin would have been the same as other planets.

        That is, indeed, what people expected. It is not what people have found.
        however, the process of building from dust to pebbles to planetesimals to planets fairly much dictates that at many stages in the process you will be getting collisions between broadly similar mass objects – “hierarchical growth” in the jargon – and that has the potential for pseudo-random outcomes from very small initial differences. If you accumulate a billion small bodies together, then statistics win and you can fairly accurately predict that the properties of the whole system will be reflected in your produced body. But if you’re assembling bodies of comparable size (e.g., the Moon-forming impact is attributed to “Theia”, at around one Mars-mass or 1/10 Earth mass), then “big bangs” are to be expected. Compare the Herschel crater on Mimas (link below), the Moon’s South Polar Basin, the Northern hemispherical anomaly of Mars, the Moon-forming impact on proto-Earth, and the loss of about half of Mercury’s volume as a series of more-closely equal mass impacts.

        I’ve been answering questions in my mind inspired by your question. The following answers my questions, but having written it, I might as well keep it. It doesn’t directly address your question, but it is relevant.

        The count of bodies in the Solar System with evidence of late, large impacts is suggestive :
        – Mercury : big hit seems to have removed around half it’s diameter, which is why it has a (relatively) larger core than any other “rocky” planet.
        – Venus : big hit leading to retrograde spin, as discussed in this thread.
        – Earth : big hit leading to mildly offset spin axis (compared to the angular momentum axis of the Solar System) and spray of debris of about 1% of the body mass which later incorporated into the freakishly large Moon.
        – Mars : suspiciously small (but that is generally blamed on Jupiter and Saturn playing orbital all-round-the-cushions trick-shots in the first 100-odd million years of the Solar System (see “grand tack” and Nice models) ; has a deep (10-odd km) depression covering about 30% of the surface, slightly offset from centred on the North pole ; the crust in this region is thinner and much smoother than the remaining crust (the “Southern Highlands”) ; a giant impact hitting hard close to the North pole (thus, not much affecting the rotation) is one popular explanation. It would need a body of around 100km diameter, 1/60th of a Mars diameter and around a quarter-millionth of proto-Mars’ mass.
        – Jupiter : when the Juno spacecraft was launched, the big question was “how big is it’s core?” What was not a high probability outcome was finding that the core doesn’t have a sharp edge. Juno has just done another perijove approach to try to improve the numbers on this and the mission has been extended with this as a major science deliverable. That “fuzzy” core is one of the outcomes you would expect from a giant impact (up to several Earth-mass impactor) when Jupiter was early in it’s runaway-growth phase (about 10-20 Earth mass). The jury is out on that one at the moment, but you can see which way I’m reading the evidence collected so far.
        – Saturn. The rings are probably replenished by lots of “little giant impacts”. And there’s that ginormous crater on Mimas – Herschel.
        – Uranus : well, it’s rotation axis is almost in the plane of the solar system – 97 degrees to the rotation axis of the system as a whole. See discussion under Venus. But even more weirdly, it’s magnetic field is not axially symmetrical. The centre-of-field is significantly offset from the centre-of-figure – a third of the planet’s radius. I don’t know what is going on inside Uranus, but it clearly hasn’t read the models of rotating conducting fluids generating self-exciting dynamos and is a very naughty planet interior!
        – Neptune : Neptune is relatively boring. Neptune’s moons, on the other hand, are … they’ve had an interesting life. Sometime after formation of the planet and a suite of dull satellites, Neptune captured the largest object known (to date) in the Kuiper Belt into a retrograde and inclined orbit. That’s not quite a giant impact – a giant near miss instead.
        – Moving on outwards to the minor bodies … the Pluto-Charon system has a mass ratio even more extreme than the Earth-Moon system, they’re even closer together, and they’re both tidally locked – Charon to Pluto and Pluto to Charon. That’s a recipe for a giant impact origin if I ever read one. Interestingly, the rotation axis of the bodies and the entire system also lies in the plane of the Solar system, not perpendicuar as for most of the inner planets. Rather like Uranus in that respect.
        – How Haumea got it’s 4:6:9 triaxial ellipsoidal shape and high spin rate – again a late large impact is strongly suspected (but data continues to be collected).
        – And the really interesting new study object, MU69 (a.k.a. “Ultima Thule”) is a very small, very slow-motion giant impact of two near-equal-size bodies which had sufficient stiffness (and slow enough coming together, and small enough mutual gravity) to not actually fragment on contact. And like Uranus and Pluto-Charon, the rotation axis lays fairly close to the plane of the solar system. (Remember the difficulty of establishing the light curve during the approach?) That feature is getting to appear suspiciously frequently in the outer solar System, I think.

    2. Fun fact: Although Venus has the slowest rotation, Mercury is the only planet whose day lasts longer than its year; Mercury’s day lasts twice its year and triple its rotation.

  3. Yes. Virginia voters turned out to flip both the state house and senate from slim republican majorities to slim democratic majorities which should help get some decent legislation passed. Republican candidates here in southeastern va did not advertise themselves as such…they ran lots of tv ads in which they never identified themselves as republicans, running under trump radar. But it looks like enough voters figured it out. Drawing of district boundaries for the next decade will be in dems hands after the census. Last time republicans had control and participated in the type of gerrymandering discussed the the book, “ratfucked”. A court recently threw out several of those boundaries which helped in yesterday’s results. We shall see what the dems do for district boundaries next year when they are in charge.

    1. The transition of Virginia from a red to blue state did not happen overnight. At the NYT, Democratic organizer Tram Ngyen explains how it happened: “Virginia’s Democrats got where they are today as a result of year-round community organizing and voter engagement.” He concludes: “States don’t become battlegrounds overnight. Democrats and national progressive organizations have the resources to take their case to the people and win, but they have to start early and organize relentlessly. When they lose, they have to stay in place and keep fighting for every political inch they can get. No place is unwinnable forever.”

      It seems that the Democrats have at long last learned the lesson to political success: organize and never stop. This process must take place on the local level. Republicans are a minority in the country, but they have been successful beyond their numbers because they have understood this. I hope the Democratic long slumber is over. If so, their future is bright.

      1. Last night’s results continue the trend of more-educated suburban voters abandoning the Republican Party of Donald Trump. Under Trump, the GOP has become the party of rural America and of the false-consciousness segment of the working class that’s put Kulturkampf issues ahead of their own long-term economic self-interest.

        1. More and more I get the sense that the American right has spectacularly overplayed its hand, and the right have not come close to comprehending how devastating Trump will be for them.

          Trump has been very, very bad, but liberalism will pick itself up and move on once he’s gone. The right however, and their basic aims to greatly reduce immigration and permanently reclaim some ground in the culture wars, will not recover so easily from this.

          If they had played their hand sensibly, calmly and rationally, and nominated a reasonable candidate, or even refused to support Trump once he’d been nominated, the right might have been able to make serious long-term gains. They might have been able to make sensible arguments against widespread immigration and against political correctness. After all, there’s clearly a hunger for those arguments.
          Instead they put it all on orange, spun the wheel and kept their fingers crossed.

          As it stands I think they will be smeared into a paste in 2020 and those talking points of theirs will go back underground for another generation. I think they have become wildly, dementedly overconfident, and for all their bragging and gloating about a permanent realignment in politics my suspicion is that all they’ve managed to do is foster an extraordinarily intense and passionate resentment towards their particular brand – most damagingly among the young, who will grow up to associate Republicans with sleaze, greed, ugliness and shame.

    2. Last time republicans had control and participated in the type of gerrymandering discussed the the book, “ratfucked”. A court recently threw out several of those boundaries which helped in yesterday’s results.

      The lower federal court opinion that had unscrewed the districts Virginia Republicans had cracked’n’packed to diminish the strength of the black vote was affirmed by SCOTUS on jurisdictional grounds shortly before the high court decided last June that such gerrymandering issues were nonjusticiable in Rucho v. Common Cause. Lucky break, that.

      Also interesting to see that Virginia Democrats made their state legislative gains last night despite the state’s top two Democrats having been engulfed in scandals — the governor and lt. governor, blackface and sexual assault, respectively — since Virginia’s last off-year elections.

  4. STOP ,STOP ,my poor brain is a melting ,which sick barsteward thinks up these optical illusions ?
    Didn’t see the cat today at Marsh Farm .

      1. Oddly, I couldn’t see any 2D, I was seeing 3D cubes rotating and transforming into ‘flaps’ standing out at 90° from the background.

  5. Shelly Simonds (D) won her Virginia seat after, “…2017 run for the Virginia House of Delegates ended in heartbreak, with her losing a random-chance draw out of a bowl after she tied her opponent with 11,607 votes apiece,.”

    What are the chances of that happening?

      1. I usually win whatever I enter. I break the odds. When I was 12, I won a picnic cooler at the Home Show. Later, I successfully guessed where the next cow would drop it’s dung at the county fair. I won a $300 door prizes at a charity banquet, etc., etc. It happens so often I feel embarrassed getting a ticket. I’ve never won “big” in the lottery though. Probably because I never enter.

  6. I am loving the morning rush hour, but it does raise the question: How does our intrepid traffic reporter get them back in the barn at night?

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