Upload #201: breaking rocks

Last day of 2022 in the New World so, may as well poast something...

For the last year-and-half I've been mostly uninterested in the Quran; although I'll have to make exception for egregious mistakes. "May The Rocks Become Dust" has lost another source: sura 83 was next to go. I also tweaked some "Egypt". And waay back in 13 June 2021 I'd slipped in a fix to the John Damascene project "Arraignment" without telling anybody because, hey, it was a new project (then) anyway.

There is more; but I haven't uploaded the fixes yet. All the fixes were minor.

And I posted four new reviews on Amazon. Stephen Shoemaker Creating the Quran, David Cook Kitab Fitan, Mark Durie The Quran and its Biblical Reflexes, Robert Spencer The Critical Quran.

Madrassa. Same as it ever was.

The Greek calendar in India

I was alerted to the Bikram Samvat, a calendar used by Hindus and officially by the Hindu nation Nepal.

India I believe prefers the Gregorian to the degree it is a secular nation. The Bharatis have been telling me also of the "Saka" (Scythian) calendar, which is solar; but I'll keep this blog off of that one for now.

The V.S. calendar is lunisolar and starts 57 BC, when V/Bikramaditya repulsed a Saka invasion. So goes the legend. Historiography at this point in subcontinental history is... spotty. Vikramaditya may or may not be real.

What was real at the time and place was Greeks - "Ionians" as they came to be called, after the common dialect of Greek they preferred. Alexander's holdings out east, which didn't quite extend to India, had come under Seleucid rule, who (famously) started a calendar at 313 BC. The Seleucids at first held as far as Bactria but, unlike Alexander, did not even attempt as far as the Indus. Then the Seleucids lost Bactria, which at least stayed Greek. Then they lost Parthia which, er - not so much. But the Seleucids' calendar remained convenient for inter-Greek trade under their old domains.

In the first AG 100s decade Seleucid king Antiochus III re-subjugated Iran and then the Bactrian Greeks, next coming down to the Indus, naming himself "The Great". Like that earlier "Great" Greek - he didn't stay. But this time, in his wake, some of those Bactrians figured, why not, let's start a new Greek kingdom along the Indus. Menander I the Saviour (Soter) is the most famed, AG 160-180ish.

AG 256 should take us to V.S. Year One. Hippostratus minted some coinage then, in silver. And yeah he'd had to fight those pesky Scythians, as Greeks name them; hence how he'd used Soter as a title too. As long as he lasted.

I'm going with that the V.S. is the first-used calendar of northern India as would mark time year-by-year.

Running before they can walk

For my Post 2000 - Nyrath reports on a conference about a lunar station overnight, night there being a fortnight here. Artemis as it happens is targeting that south-polar basin. It promises eternal shade but honestly, should promise eternal daylight in places as well.

I have to say, the article is bad and its editors should feel bad. It reads like a press-release; first blathering about how awesome NASA is and then spinning off to some cods about NTR/NTP and NEP. We are not firing these torches between Earth and our Moon. So, in an article under a Lunar title, please don't even mention this stuff.

It's nice that they are planning power-sources as will work overnight. But. At first each stint will likely be daylight; be there for a week and get off the rock. I say a week because we have to ask how to handle the dust longer than Apollo 17 handled it.

The next step, then, isn't to find energy-sources as will work over the dark; but to find such as will not break over the dark. In between human visits.

The Jacobi Integral is no invariant outside a system

It occurred to me that the Russell / Ocampo / Longuski cyclers are, also, defined in terms of a unit (inner) circle. I'll start with the Aldrin and its precious cargo of fuzzy li'l rodents.

Aldrin like all cyclers starts at {0,1} in a frame-of-reference heading down - turnwise - velocity {2π,0} per Earth year. It actually starts at the highest orbit which Earth-Luna share as we can get it; but nobody is calculating this. The liftoff, we assume, has one of Cole's gravity-deflection fields so its beginning vector in sidereal terms is {-0.9198936, 7.3104506}.

For awhile the Aldrin is scraping close to Earth so I'm starting my timer when (xy - sat).Length() is 0.161724165 AU. This {0.5881579, 0.81678015} allows 1.00650859 AU from the Sun so we're actually almost 1/6 our way to the equilateral - to leading L4. 2Ω rounds to 3.000 as we'd expect. Velocity {-5.30233, 5.0659566} but we'll take off the velocity-vector of the frame, which is {-5.1319814, 3.6955051} here. J = 2Ω - 1.38099813*1.38099813 = 1.093. That's the system invariant so I get to keep this. Right? RIGHT?!

Let's [eff around and] find out. With the higher potential that 1.36659813 AU gets me, still 0.3666 AU from home: 2Ω=3.331. Aldrin's speed in this part of the frame comes down to 3.86913 AU/year. J is now -11.64.

Yes, we've kept the Sun at the zero-point, not opposite Earth. But.. cyclers run a long time. Longuski et al. were planning on the synod, not the year; by preference two synods, like S1L1 or 2-3-1-5. Jupiter orbits at 11.86 Earth years so is noticeably budging our Sun over the spans in question.

A reminder that this is a cycler so will be coming back to Earth. At a high Vinf, granted; so it's not a free return-squared. Still. Should I not have had a low negative Jacobi, at the start?

I think once we've left a system, Jacobi just gives up and tells us we're on our own.

The quaternion

I had occasion to transform an angle recently. This to find the velocity of a body on Kepler's ellipse. Therefore: the unit tangent, multiplied by vis-viva. If I'm pretty sure that the body is at, let's orient it like a computer clockwise, {-1, 0} and that the eccentricity is zero then I should be looking at {0, -1}. So {y,x} right? But {0,1} behind it slides into {-1,0}. That's {-y,x}; this defines the right-angle transform. Obviously orienting the page so that y increments upward doesn't change this.

What has happened is matrix-multiplication. Luckily 90° is easy. For anything else, unless I am certain of my x,y quadrant: a lot of sin-theta awaits. Luckily, computer-science has resurrected one of Sir William Rowan Hamilton's less-favoured mechanics - the Quaternion.

As of the early 1990s pure mathematicians (like me, then) used vector analysis. At some point, though, I'd caught wind from the comp-sci department that we weren't quite done with Hamilton. I'd even seen a book about quaternions in 2010ish - but I didn't pick it up. Now, 'tis time, with the System.Numerics Vector3.

What we do is to define our transform, Quaternion.CreateFromAxisAngle(Vector3.UnitZ, (float)Math.PI / 2F) for the right-angle in radians. Vector3.Normalize(Vector3.Transform(xy, TurnwiseRightAngle)) will get the job done, returning a unit angle of velocity to which I'll apply my speed.

TurnwiseRightAngle looks like a unit-z vector, with a similarly-unit floating point "w" which represents the angle. Although w is not the angle; it's 0.707. Square-root of one half; the cosine (and sine) of the right-triangle. It turns out that the "unit-z" was 0.707 too. Do I know why?

I don't know if I care. I got some small floating-point deviations. new Quaternion(Vector3.UnitZ, 1) * (float)Math.Sqrt(.5) will do for a quicker TurnwiseRightAngle. C# doesn't let this be commutative; there's no overload in case I want this in reverse. Oh and I got errors here too. Probably due to the usual CPU follies.

Anyway as noted all I needed today was {-y,x} which doesn't introduce errors. At least we have this lore in case I need it later. Like .CreateFromAxisAngle(Vector3.UnitZ, (float)Math.PI / 6F).

AVX2 and beyond

Leafing around Metacritic - on account of a Steam sale - I stumbled upon the Uncharted port for PC. Yikes!

That stuff I was talking about, about vectors? If you want this game on PC you need The Haswell New Instructions to get those vectors. The instructions were new back in 2013; I'd just taken this for granted by now.

I'd not counted on my fellow Uncharted fans. These guys are even less new - shall we say, more /vr/ than /v/. The whole Uncharted series started as a PS3 showcase, in the late 2000s. So these fans're on laptops and PCs like... well, like this old thing I'm poasting from. I wouldn't dream of downloading a post-2010 game onto this throwaway. Maybe not post 2000.

Honestly this looks like a point-of-sale issue. It should be okay to tell downloaders that: yo, your rig cain't touch dis. Then they don't waste their money; or if they do, they waste it on a 2019+ machine, first (like I guess my family did).

Orbital capture

Once we have a Jacobi, what do we do with it? This is what Woolley and Scheeres posed in 2010. If nothing else, it checks the sanity of J being so close to three (3) near every orbiter. Yay, I'm certified-sane.

The paper goes beyond 3-body J to Hill's Problem, which is Venus' problem midrange in that Hill-Sphere. The distance to m₁ - the sun - is presumed infinite and μ₁ is much much greater than Venus' μ₂. As intimated yesterday, I'd been dealing with main-body orbits, to pass from (say) SV-Hilda, or maybe a Hohmann from Earth, up into Venus' Hill.

Woolley-Scheeres figured that with these, with Vinf which I've seen here-and-there, and with Tisserand's Invariant which I don't know at all, plus some Normalization Parameters for a few moons: we might use a hyperbolic periodic orbit to inject our craft. I assume first is to orbit around Jupiter or Saturn, which makes that planet the μ₁. I mean: our own Moon is one of its examples and we're not coming in from Mars, here.

Uranus got dissed as usual so, if we are coming in from a Hohmann or even a biëlliptic, the method should be usable to go there. I assume Venus should be fine as well as its distance from the Sun is nowhere near as problematic as Io's from Jupiter, which isn't even Keplerian.

The Ceramic Age in the north

I'd thought pottery was a stone thing in the Stone Age. I was unaware of clay being fired west of Jomon-era Japan until 7000 BC well into the Mesolithic, by farmers or near-enough, in Anatolia. It may be that [eastern] hunter-gatherers were potters too.

This isn't quite the W that Graham Hancock would imagine; these HGs were inland, not the mediterranean-polynesian coastal peoples he's theorised. Still. It pulls back one of the mainstays of "civilisation" further in time. h/t Saraceni who has been doing a lot of this today.

Ceramics would, in this new study, have started 20000 years ago: 18kBCish. That is... very ice-age; this would at least account for the Jomon. ('tis further parallel to transiberian arrowheads, also tagged Ainu...) Clay pots in the "Urals" are still pegged to earliest 5800s BC (perhaps: Khvalyn) ... but thence spreading to Scandinavia, not thither from the Near East. By then the Near Eastern ceramic-age had already spread from Anatolia to Jericho. So: this piece claims that Anatolian pottery had nothing to do with anything north. The Urals' potters were EHGs, taking their cue from further east; and so became the Scandinavians' potters.

This looks cultural. I still maintain the Scandinavians had been made aware of Near Eastern (Balkan!) ceramics. But if this study holds up then the Baltic chose, instead, to inquire of the steppe.

UPDATE 3:50 MST - Greater Caspian Atlantis? Cue up the new year . . .

What we have learned, 2022

In this annual tradition, we take stock of The Year That Was in astrophysics. A day late for Mars but we're on an 365.256-day sidereal plan here.

On a personal note my eyesight deteriorated, so in June I got readers. Lenses great; frames brittle, so I got another set last fall. Which turned out to be too strong. So that's what I use to read on the road. Also a few weeks after June this laptop died and

The biggest deal for my Venus project was the Jacobi Integral, stumbled upon last month but sussed only last weekend, giftwrapped best-I-can-tell by the sainted Myrene Bishop himself. I can also thank Gereshes' one example although I assert I have explained things better than he did. NO thanks AT ALL are due to the Wikipedians nor to the Wolframites who fell down on providing any useful code nor even the basic units we need; all Wolfram could do was to buttress Gereshes. Even Gereshes split his takes across multiple sites mainly posting hypnotic animated GIFs over explanation. This has led to updates of the SV-Hilda project.

Although I didn't study Molniya orbits I did find out about them. Expect a rethink of several pages here, like how Venus high-orbit interfaces with itself and with L4/L5.

As for material science I found that ramjets tend, er, to melt. That's intransitive, not just transitive. That affects the Pluto system for Venus and, indeed, potential uses for nonnuclear-heated systems of that sort (because Venus high-altitude might use solar, not plutonium). We also bought a book from 2020 which suggested balloons fit for spaceporting on both our worlds. We reconsidered the use of toxic Hg both for propellant (interplanetary only) and for solar-power.

As for general wellwalla, some news came out of Mars. I'll admit this blog isn't on that beat; hence why we didn't blow off fireworks yesterday. Although a beating was administered, to lazy Martian explorers. I refer my readers to Zim's BehindTheBlack for that beat overall. Progress has been incremental this next planet outward (despite the laziness) but, it is progress. I do believe we have uses for the Venus clouds and for the planet below Deimos... prison. Because interplanetary commerce between here and Psyche/Ceres is to focus on Venus' orbit and on the moon Deimos. Sorry.

Past the Belt I found (scattered) explanations of the Laplace equations, generalised past 4:2:1; first for mean-motion then for the longitudes. More-sincere thanks go out to Papaloizou and to Fei Dai et al respectively. I'd have preferred they all be in one easy textbook but, as with Jacobi, I couldn't find one so had to write that textbook, only possible due to their moron-readable explanations. As commonly noted it takes a genius to explain sh!t to morons, or ex-morons as the case may be. This helps a LOT in Newton-simulators where the bodies be in resonance.

Taking Laplace and Jacobi together we pondered using Amáltheia for shielding Jupiter's planet-sized moons especially Io; and maybe a manmade station betwixt Europa and Ganymede. The latter two moons, at least, might not need the shielding I'd assumed.

Now the para to what this blog DIDN'T WIN. In general iceworld news the ramjet was found in the process of understanding an Antarctic Ice Gun envisioned by some Pole back in the 1990s. This was worked in May when, as noted, my eyes weren't up to it. Requires more chemistry knowledge than I own. Took the L. Same goes for an even-more-abortive attempt at the constant-G Pursuit Curve - which I'd wanted from the new stations I'm putting up as interplanetary cyclers and, of late, for Europa/Ganymede. This, early July. Might try again later.

Evenfurtherout much of the Jacobi and Laplace stuff was found by looking into newly-found extrasolar planets with such parameters. We also found many more browndwarfs and a literal Soundgarden System. Although, this might be harder (or softer) SF than this blog prefers, so - no links. The Gaia 'scope keeps delivering; Webb, after much ballyhoo and expense... not quite there yet. And we lost some planets, mostly around Barnard's Star again but also Proxima Centauri.

On the data-analysis side we got a better algo for sussing the data. Can we nail down the Alpha Centauri worlds?

Back to a personal report some computer-science was done, pondering bithacking leading to vectors in a multicore. Some of the latter went toward fixing the Newton-sim I'd used 2007-2021 especially for performance. I also figured out longitude for a Keplerian ellipse; wiki was of actual help here. The elliptical circumference was also pondered although there, just enough to (vaguely) understand some (bad) cryptology.

Campbell the Christophobe

I've run across several books by Christians presenting their "evidence that deserves a verdict". Josh MacDowell is the most notorious (I'll grant that he does instill a love for the scholarship); others include David Limbaugh, and Lee Stroebel. W. Mark Lanier recently stuck his oar in.

In capsule I gather Limbaugh acted ethically as a defence-attorney. MacDowell presented his case as a prosecutor: convicting the kerygma as being true. Stroebel best I can tell presented himself as the prosecuting-attorney who eventually must abandon his case although I admit, I just watched his movie. This showed the earlier conversion of his wife, which would dismiss him from the case immediately for conflict-of-interest, so if you read his book - well, as Barnum calculated, births-per-minute = one. I know nothing of Lanier.

Today I found John Campbell's Cross Examined. This promises such a prosecution as actually prosecutes. This alone elevates Campbell's ethics over those of Stroebel. We'll get to Campbell's own biases, anon.

For Campbell, Christianity is not a mere "religion" but a "social organism": a political-religious system. To interject: if you have attended at all to Byzantine-era theology you know this to be true. Everything in the Monothelete debate hinges upon what a "church" even is, when the whole Empire be Christian. Campbell argues that, as such, the whole system must be interrogated; if it is not true, then Christianity must, er.

Campbell professes no hostility to Christians. But Christianitas stands athwart action on climate. Christianity blocks gay marriage (sic) and stem cell research, as well. Christianity is "patriarchal" which, I gather, Campbell is not. Campbell stands instead for the poor, the underprivileged, and the marginalized.

As with Muslims, it is difficult to comprehend how the believer can remain What He Is if his belief is wrong. A new-atheist stance would have suited Campbell better.

Campbell and I likely agree upon what "poor" means. By contrast "underprivileged" and "marginalized" depend upon what Campbell believes belong under legal-protection and in the social-centre. In sociology these words are terms of power. In short they are Newspeak. Campbell would push Christianity into the margin(s) and remove privilege - state protection - from the Christian church(es). As El Guapo would say.

I could counter Campbell that philosophic arguments exist to demand State privilege to the heterosexual definition of marriage, to the preservation of human life (on the margins, we might say), and to medical-ethics in research. I will go further: unless these philosophic tenets are affirmed, with the power of the State, the religion - any religion - is pointless at best and evil at worst. From the humanist perspective.

Christianity may or may not be strong enough, anymore, to affirm Life against "Science". I'll consider a book which argues against Christianity from this standpoint; it can then get down into the biblical-scholarship and the contradictions against what we know from the natural world.

But there is no point in considering any book from Campbell on good-and-evil as long as Campbell is not on the side of the good.

Amáltheia to Io (with maths)

Let's Jacobi that Amáltheia outbound. Our units are Io's, pretending that the other moons and Jove's own tides aren't messing this up for us. And I'm pretending the small moon orbits circle-y. Wasting no time:

var xy = new Vector2() { X = 181300F / 421600F, Y = 0F };
var muSmall = 0.014960 / 317.8; //neglect 1.1988e-06
var dxy = new Vector2() {
  X = 0F,
  Y = 2F * (float)(Math.PI * (Math.Sqrt(1.0 / xy.X) - xy.X))
};

J is -42.492. Check out the reciprocal-root! But I am in no hurry.

Meanwhile let's look at JIL1. This system being Laplacian, there really isn't one... instead I'll use direct-reports of Io's Hill-Sphere. This is 5.8 Io's radius.

var xy = new Vector2() { X = 1F - 5.8F * 1821.6F / 421600F, Y = 0F };
var dxy = Vector2.Zero;

Target J is 3.00557659591. Looks about par for these. Amáltheia by contrast is not par with the SV-Hilda; it looks more like a Mercury, deep down there.

Venerean Hilda's Jacobi

The dubs won around here last weekend (excepting the Texans') started with Laplace's longitudes which had troubled me since, I kid ye not, 2007; when I had a Newton simulator sucking planets into their own sun. That afternoon I figured Jacobi so could apply it for Venus. 'Twas a good couple days. Today I shall apply Jacobi to Venus' customer SV-Hilda.

SV-Hilda shall take Venerean AU. At perihelion she is Y=0. Since any Hilda period is by definition 3:2 we mark that 2/3. Kepler's ratio is 1 in these units so semimajor is Math.Pow(2.0/3.0, 2.0/3.0) which is 0.763143 Venus AU so 0.55175 ours.

I'm doing an ellipse, on account Jupiter's real Hilda likes that. The main constraint I saw in 2020, so now, is Mercury: that aphelion is 0.466697 Earth AU with Solar L2 [+.2roundup] 0.49. 0.49 peri' is Venereal 0.6777 AU. In the planet's direction so X=+0.6777.

Next up: velocity, from that same +0.6777 done on the Y axis only, following Venus also in the positive direction. (Our Hilda's eccentricity maxes 0.1119.) Velocity = √(μ[2/r-1/a]); at r=a=1, v=2π AU per Venereal year; so unit μ=4π². Now we run with r = xy.X:

var xy = new Vector2() { X = 0.6777F, Y = 0F };
var muSmall = 0.815 / 332946;
var dxy = new Vector2() {
  X = 0F,
  Y = 2F * (float)(Math.PI * (Math.Sqrt(2.0 / xy.X - 1.0 / (float)Math.Pow(2.0 / 3.0, 2.0 / 3.0)))) //it'll be fffiiinne
};

J is -61.365... whuuttt. My speed must be too high. Unless it is not . . .

But! the whole frame-of-reference at Venus runs 2π. Y was real, in Venus' units; let it be situational, in Venus' frame. The circle at r (Hilda peri') is 2π x 0.6777 so, is doing that per year. 2F * (float)(Math.PI * (Math.Sqrt(2.0 / xy.X - 1.0 / (float)Math.Pow(2.0 / 3.0, 2.0 / 3.0)) - xy.X)) and J is -10.955.

This is still (magnitudinally) a lot - but we somewhat feared it would be. The need is for a delta-V to get from -10.955 to SVL1 (or L3) at just over 3.

Laplace's longitudes

Here we go: for generalised Laplace longitude λ, resonant-angle φ₁₂ = qλ₁ + pλ₂ + (p - q)ϖ_1,2. p and q here are the p:q integers although, yeah, first-order such that p = q+1.

We know Europa/Ganymede (like Mimas/Tethys &c.) is just φ₂₃ = λ₂ - 2λ₃ - ϖ_2,3. After some definitionals and mathematics which the arXiv did for us already, the angles on our station:

φ2s = 3λ2 - 4λs       + ϖs
φs3 =       2λs - 3λ3 + ϖs

The latter is like φ_bc for TOI-1136 although, of course, φ_cd was 2:1 over there. Subtract 'em out and: φ_2s3 = 3λ₂ - 6λ_s + 3λ₃. So, when λ₂=λ₃ at conjunction which we'll define as zero, λ_s = -180°/6 = -30° so, behind them in their common rotation. I'll leave to the nerds how to transform the vector.

For Europa/Ganymede (far more so than Ariel/Umbriel) we must always remember that at 0° conjunction, Io's λ₁ = 180°. Really -180°, pulling our station back. Simultaneously Europa and Ganymede are all pulling our station forward; mighty Ganymede upward, at that. Hence libration. Which we're not competent to do here; especially considering Jupiter's own tide.

Barnard's Star just cannot get a break

When I was a boy, much fun was had at the expense of Barnard's Star, what with the planet it didn't have and the poor obsessive Peter van de Kamp who didn't find it. The Nederlander Percival Lowell, was he. Now - starting last summer - the next generation gets to enjoy this non-system; here from the line-by-line method, which might actually work.

Enjoy the hat, fools. I'll admit: I'd bought into it myself, although I didn't blog it. I did unfortunately blog the wrong Proxima c but hey.

The biggest winner might well be Fred Pohl for his shadecast in Gateway. Excepting: why were the Heechee ever at this nonplanetary system? - maybe for the same reason we were, we'd all hoped there'd be something.

Laplace for 4:3:2

To constrain my 4.75-day station between Europa and Ganymede, let's look at Laplace for this. Pierre-Simon himself was working with 4:2:1. This is p+1:p and q+1:q where p=q=1. My station is the 3 in 4:3:2; my p=2 and q=3 (I tried 3 and 2, trust me, it doesn't work). Papaloizou's mean-motion equation is (p+q+1)n₂ - qn₁ - (p+1)n₃ = 0 . . . for the case where all the resonant angles are stationary or undergo small amplitude librations. I know that Jupiter+Io tides are going to mess this all up. So I'll flip Papaloizou such that, when this equation is satisfied, the librations are at minimum.

6n₂ - 3n₁ - 3n₃ = 0, then. So, the mean-motion of my sat will be (101.37472576024707 + 50.317609222086183) / 2 = 75.846167491166625 °/day; 4.746 days or, if you like, four days 17:54:14. 5.76 minutes off my 4.75 estimate - not bad, if I do say so myself.

Also kinda redundant. I suppose the next step would be longitudes. Like: when Europa is at λ₁ and Ganymede at λ₃, I need λ₂. For 4:2:1 λ₁ - 3λ₂ + 2λ₃ = 180° but what's that for 4:3:2?

And they chained the dragon

Good news! ChatGPT is Three Laws Safe. Bad news - the three laws are Environment, Social, Governance.

It is thus proven that Asimov's ethics are practical, at the Lessig level. ChatGPT's proponents were not counting on the code being written by Current Year. Current Year actively wants harm to you.

A win for the artistic elite: ChatGPT was not destroyed, only made their tool. @EMostaque was wrong but for the wrong reason.

Memory lane

Shoemaker's sixth chapter is "Remembering Muhammad". Coïncidentally, we're hearing a lot about how public-speakers handle memory these days. Delivering the lulz for the lefties is Representative-elect Santos to which Ace is here with some whaddabout. I suggest reading the comments for Hillary!'s memories in Bosnia (and Brian Williams', wherever that was), Richard Blumenthal's brave service in not-Viet-Nam, and Elizabeth Warren's buffalo droppings. Shoemaker's chapter dares overlap some of these!

Well... sort of.

Shoemaker gives Hillary! some benefit-of-doubt, as well as Williams. He adds John Dean for good measure. Even Shoemaker can't pull Da Nang Dick and Lieawatha out of the muck. He doesn't touch our lord and saviour Obama because he hopes to keep his job, not end up as some blogger somewhere. Shoemaker tries as hard as he can not to call the ancient Salafs and Tabi's liars. Whether Shoemaker thinks that, underneath... well, he gotta do what he gotta do.

Overall memories tend to make the "memoriser" a hero of the story, as Shoemaker says we all do for our own stories. Overall to do hadith you have to memorise that hadith - with paper. Same for quran to the extent that's any different.

Shoemaker's wisdom might be wise for all of us, even nonpoliticians.

Mars never was breathable to us

Mars has free oxygen gas but at levels suggesting radiative and chemical breakups of oxygenated compounds, not plants. Apparently in 2016 there was chatter that Mars used to have more of it, in order to make manganese oxides; therefore, plants. But where are the plant fossils?

Those of us who said "hold on to your thoats" (or, like me, didn't pay attention) are, h/t ToughSF and the Mars Society, vindicated. On simulation of Martian chlorine-rich surface-conditions, those produce those oxides. More: added oxygen can-not produce those oxides.

Back to archaea! And, for colonists, back to the artificial means.

Studies in misanthropism

Most assume that pure meritocrats and White Advocates belong together as "racists". In fact they are opposed, and - as usual - the problem is the Jews. Cochran, Murray, and Derbyshire believe that Jews are just smarter darn it. MacDonald and then Unz have argued, in parallel, that the Jews have crowded gentile Whites out of the Academy, not entirely through their raw (mostly verbal) SAT and not entirely by accident. So: let us (re)visit Yuval Harari, who in 2018 told the WEF that humans are going out of style.

On behalf of White Advocacy, Karl Haemers popped up on Unz today, trashing Harari's comments in 2018, before 2018, and since 2018.

I can confirm that Harari's Sapiens was much beloved of midwits through the 2010s, before That Speech. I've seen the book around the stores, not taking it seriously, only borrowing in a trade late March 2018. It was a mixed bag overall. I thought its heart was in the right place, endorsing that IQ is good as we all should. But by 2018, David Reich and his whole coterie of geneticists had overturned a lot of its assumptions.

Harari, as Haemers reminds us (obsessively), is a Jew and a homosexual. Harari might think he has been put here to make the world better for the generations he himself has no hand in generating. Herr Haemers doubts that Harari could possibly care about the long-term future of the goyim. I submit that Harari is not, here, supporting the longterm aims of Jewry nor even the Rainbow.

I think what he have in Harari is a rank misanthrope. He doesn't like humanity as it is and wants a better one. His books target IQ 115s who wish to think of themselves as IQ 140s, so align themselves with (possible) IQ 160s; and what better way to present as a smart guy but by waving-off the dumb guys. But Harari's IQ is not 160. It's probably 115 too.

David Reich is your 140-160 if you want one to follow. Actually so was Vox Day once, before all the drugs he did in Psychosonik, so... be careful out there. As for Haemers, er. He looks like a competent research-assistant, but his prose needeth much editing. On assumption that pure rage lowers IQ, it may be that Haemer's IQ is higher than he is letting on. His IQ will, of course, fall as he gets older. Memory-care awaits him, I fear.

The Escorial's holdings of Arabic MSS

As some of us are talking Portugal, let's talk Madrid. Specifically: the Escorial collection of Arabic MSS.

Apparently many of these MSS had taken a roundabout turn. Famously Cordova / Qurtuba was a haven of scholarship, not only by West European standards but also by Islamic standards. Eventually, however, the time of Islam had to end in Spain so many of those MSS were taken to Morocco. The Moroccans were very interested in Andalusian material by then; there's talk that Andalus itself had lost interest in Qurtubi's tafsir (pdf) but the Moorish library stored many copies thereof.

Sadly Morocco by then had a bit of a Dark Age problem too. One of the amirs got into a scrape, packaged up the library and then... lost them to French pirates. In 1614 the Catholic monarch of Spain (and Portugal) got his hands on the library and moved them to Philip II's palace at Madrid, the Escorial. Can't really say "back" to Madrid; note I didn't say Cordova. At least they didn't burn it all.

Er. Well, not on purpose. Sigh.

In the early twentieth-century Anno Domini, some Frenchmen made up a catalogue, in French so that nonSpaniards in Europe could see it. Arthur Jeffrey trooped down there to check out Marandi's commentary on Ubay and other "off" readings in the Quran, the Qurrat Ayn al-Qurra in MS 1337. Read about it in Tomo 3. Jeffrey noted peevishly he was unable to return to Spain in the mid 1930s; Madrid was Republican (subdivision: Stalinist) and under seige from 1937 on. Franco himself was pro-Moroccan, so had that motive to stymie any further publications of Materials For The History Of The Text.

Meanwhile, the Moroccans kept bugging the Spaniards for what was left of their ex-sultan's manuscripts back, reasoning - sensibly - that the Spaniards had enjoyed all the mathematical and classically-translated lore they were going to get, and all that was left was the Islamic lore, which the Spaniards clearly cared nothing about. VERY recently the Moroccans were allowed to do microfilm of the MSS.

Although I question the quality of the microfilm. We still do not own an edition of (say) MS 1337; just an entirely illegible PDF someone did a decade ago.

Behold, the winter is gone

Quick: in which Testament is Hanukkah mentioned? The answer is: the Gospel of John, in its literal translation enkainía.

I assume of my readers that you knew that already. (I admit - I didn't.)

The Encenia (to Latinise) isn't, I think, noted anywhere in Qumran, which was antiHasmonaean so did not store 1 Maccabees (nor Jason of Cyrene "2 Maccabees"). There's a Simoniac calendar but you know how the Essenes were with calendars.

Before all that, the menorah looks like a midwinter takeover from ... somebody. Somebody who saw a fight between the light of summer against the darkness of winter. In Jerusalem / Judaea at the time the winter would have been the storm season. Not everyone likes SR Donaldson's Rain Sun. The Song Of Songs 2:11-12 waxes poetic on how the winter is gone and the rains are ended, flowers appear on the earth [NIV]. (Not considering the Desert Sun on its way...)

I wonder if the menorah was brought, not from Babylon or Egypt - but from Iran.

Shadow U

The university was founded by the Church... so Tom Billings mooted. Really the system was something of a renaissance, if you will. The "Late-Antiquity" before the Middle Ages kept alive a classical form of higher-education, among Syrian Christians and Jews, in Iraq; which became the House of Wisdom under the better Caliphs there. But either way the "university" of Catholicism and, honestly, of Tudor Episcopalianism was no home for scientody.

I've long noted the case of (deep-Asian) Islam. On our side of the world Napier the Scottish Protestant got his stuff done at home too. Much astronomy was commissioned by kings who paid for the 'scopes; or by rich eccentrics. They'd submit their "letters" to a "Royal Astronomical Society" which, note, isn't Cambridge. The Church commissioned, er, Latin. Greek if you were Napier and took trips abroad.

It's been impressed upon me how much learning has been done privately to this very day. Percival Lowell anyone? For another instance the /√ algo. Throwback to the days when quartic equations were solved by Italians in secret.

Now we have a new Church, committed to diversity and to equity. Inclusion too!

University types stuck with this new Clerisy don't respect us. They figure they paid their dues. Deep down I feel like part of the "dues" they've paid includes truckling to the sociopaths running their departments. A professor who keeps his research in hiding will resent those of us who don't have to hide.

As far as monetising real work when you're not in the academy, er. Some people do youtubes but Google deplatforms too. Other people put out documentaries about the Atlanteans or books through "metaphysics" publishers. Not exactly real work. I reckon we should do it anyway.

Artificial Intelligence art

When I attempted self-publishing, I didn't have money so didn't hire an artist. I also did not steal my art. The art I used in my pages was on the level of scholarly fairuse quotation; my cover art - the monetisable art - was 19th-century Orientalist. I felt guilty enough to credit everything. Including the fonts. Including the software.

We now inhabit a world wherein people who are not artists can charge cash for doing art which artificial-intelligence "AI" can extrapolate from other artists' body of work. I suppose, like how I'd used art-progs to colour in Throne of Glass - but more so. This means pace @BigPapaFox2 that I do not expect the Macaca Precedent to hold out forever.

Winchell "Nyrath" Chung, a fan of golden-age-SF, and a supporter of modern artists, has been raising several flags here. Most artists he's been linking, I'll disclose; I'd not consider for myself, anytime soon. But. For my readers I'll put it this way - if you enjoy what Jinjerzilla does, and you thought Tay was #based; then what if some jerkoff did a lot of Jinjerzilla pastiche and sold that. Or: StoneToss. Or Day-By-Day. Old-school B.C.?

Having hung around Nyrath's Twitter, I predict that guy would laugh and laugh. Ah but I am not finished yet! - Frank Miller, Bill Willingham. Can we get a Mark Millar? Yes yes, they were writers, not doing the art. But visual artists worked for these Problematic graphic-novelists. Someone's ox is going to get gored.

Here at the Baghestan, we like to think we be more principled.

If you choose to steal art, I suggest stealing as I've stolen it: from the artist's grave. That is - take the stuff you find in the most-ancient book covers and comics you can find, before the copyright hits. Then send ChatGPT thataway. Don't rob artists as are still alive; whether they be taking commission currently, or no.

I have a faint feeling that our artists squealing the loudest against AI Art, because PLAGIARISM; might not accept these terms. (Good chance is that the modern artists are using AI as "aids" right now, anyway; like the Orientalists took photographs in Algiers, went home, and used that as a basis.) THIS JUST IN 12/23: ChatGPT has been chained. @EMostaque meanwhile looks like he's converted to Christianity (as Razib has defined it) so will be not-poasting until the New Year.

Remotely-activated wipers for dusty planets

Swapna Krishna offers some excuses as to why we don't wipe down the panels when they get dusty. I say "excuses" because they aren't good reasons, long-term.

To sum up - wipers, as such, stand to scrape the panels and make them less efficient. Also they are extra mass at launchtime, and more engineering to keep working after the four years in which they are needed. The mission itself was sold as a two-year mission with the extra two being a bonus. (Many of our missions have overstayed their expected lifespan in this way.)

I'll say here that if every gram counts, or every "ounce" as a servant-of-the-Empire would say (Americans are silly this way): then, also, the grams taken to lift the same mission again must count, for when the first mission ends. If we see a pain-point, relieving that pain-point will, yes, bring us to the next pain-point. But: we've still gotten through that first issue. We've delayed the day in which we need to boost up something else. I assume Swapna K dislikes Elon M? then stick it to Elon - today is not your day to boost up another mission, tell him.

As for that first pain-point: Earth-rated wipers are probably bad for Mars, yes. Krishna explained the problem adequately. But. The next trick is to devise a neo-wiper as can undo the Martian static cling. This is an engineering problem. Speaking as (software) engineer, I find that bosses dislike when you tell them "no can do, cap'" and expect to be paid anyway.

Overall Krishna needs to side with the lander and with her viewers, more than with the NASA (or whichever) team doing throwaway missions. We need these missions to last longer if we want Earth colonists to last longer.

Kepler-60's two possible systems

Kepler-60 (italicised) or maybe KOI-2086 is another exoplanet-transit system. It doesn't have its own page on Wiki possibly on account that the planets aren't fun for SF writers. The three found so far are all subNeptunians well in the Venus zone or worse. Maybe there's a fourth in an outer, better spot. Ehh.

I'm interested because it has a Laplace-like resonance which isn't binary. b and c rock 5:4; c and d are 4:3. The base maths can be had from John C. B. Papaloizou "Three body resonances in close orbiting planetary systems: tidal dissipation and orbital evolution" (arXiv; IJA Apr 2015, 291f if you want to pay for it). Goździewski's quartet thence extrapolated: here might be full 5:4:3 rather than a chain. This has implications for migration-theory because migrations break multibody resonances into chains of pairs, or into no true resonance at all. I mean - look at the Grand Tack between Jupiter and Saturn, and the havoc they raised.

Those calculations were based on the data at hand in 2015. Already the masses were fairly-well constrained since these are transits so sin i cannot be must less than 1. The lightcurve was, however, noisy - too noisy to decide which resonance. Since then the assumed values have been corrected according to the Gaia telescope's DataRelease2. Since then, DR3 came out. No, I won't download these tables. Then there's the line-by-line method.

Which resonance, 5:4+4:3 or 5:4:3, would constrain the mass better still. Goździewski et al. fed their data into some 2003 algo called "Mean Exponential Growth factor of Nearby Orbits".

I don't know that I need to pull this like I'd pulled (say) Lambert two years ago. I just know at this point that I must be a reporter rather than a speculator. Papaloizou on the other hand looks interesting for tracking the 4:3+3:2 of Kepler-90def... or what I want for Jupiter.

Vector synchronicity

As I was looking around for performance-enhancements as computers are supposed to do, I stumbled onto the latest .NET upgrades with vectors.

Around about 2007 we've been getting warnings about how Moore's Law is over for raw chipsets and how we should be turning our thoughts toward parallel-processing instead. That async/await stuff you see in Node.js came out of this. Lately there's been a .NET upgrade for us VS2022 enjoyers; here is the rundown. We learn here about Single Instruction Multiple Data.

Vectors have been around awhile; in my Newton simulators I'd used 2015's Vector3 for, er, vector arithmetic. This was System.Numerics because I didn't trust that the free Unity engine wouldn't be yanked from me.

I mean, vectors of very small amounts could always be mocked-up; just do bitwise arithmetic with masking (bro). That is, if you wanted "for i from 1 to 16 do this to each(i)" you do "for i from 1 to 4 do this to a vector of 4 each(i)". I don't know if they'd said "four lanes" then, but they do now. With classic Microsoft 256-bit bytes, that's not so bad for (say) colour. In practice, you run out of size; a 16bit 386 processor got you two lanes of these bytes at a time. Hence why the colours were so cartoony up to the middle 1990s. 32bit would at least get you that colour-processing, to the limit of your CRT monitor, maybe even to tetrachromacy. But we're still not getting the parallel decimal-maths we wanted - even up to 64bit.

What I didn't know, and should have, is that in a multiprocessing world, you can enlist four (say) processors at once. You are no longer stuck with the bit-depth limitations. Vectors can be processed in the CPU now! Another fine example: the Mandelbrot, which requires independent processing upon each pixel in your window. Another example would likely be Newton upon each interaction in a n body system. Cuts time to a quarter...

...if, that is, you have those four cores on hand. .NET claims version 7 can tell how many cores will be on hand. Although if you are not a noob (I am a noob) you'll still be fumbling with the binary-arithmetic and maybe even running "unsafe" C#. For best results with unsafety please use RUST.

It's a bit like that Newton-Raphson unrolling we'd seen back in Quake III's rsqrt - and in fact should start as an unrolling. Except: Newton-Raphson is iterative (even if only iterated once). Where not iterative you can do your calcs in parallel, and should.

Amáltheia to Io

Around Jupiter, the analogue to Hyperion 255 x 163 x 137 km 5.6e+18 kg is Amáltheia 250 × 146 × 128 km 2.08e+18 kg. For whatever reason we've Anglicised this to Amalthea rather than true Latin Amalthia although the pronunciation is about the same.

Where Hyperion is out between Titan and Iapetus, Amáltheia is inward of Io. Hyperion's rotation is chaotic whilst Amáltheia is locked. Also Hyperion is white ice and cratered where Amáltheia is red (from Io) and a rubble-pile.

One more thing: Amáltheia is certainly going to precede Io as a shattered source of Jovian rings. I've recommended disassembling Phobos before Mars loses it, starting with for a radiation-shield. What can we do with Jupiter's doomed moon?

This one will be difficult. The radiation down there is awful. It has been so bad that we don't have any good photographs: the Galileo lost too many electronics on its way past, and the Juno isn't even bothering (UPDATE 12/23 although there's a shadow, and oh yeah it is indeed hard for Juno too). Also this far in Jupiter's well what exactly can a miner do?

The least-energy idea is to raise as much rubble as we can to an Io capture - assuming the Jacobi Integral still holds for a Laplacian system. Around Io one might work this rubble into an orbital ring as to shield that moon. If this works then Io is clear for human or at least electronic mining-operations, and can work with the rest of the Jovian system as desired.

As for its remaining billion-ish megatonnes, er. A habitable Io might not (anymore) need any of it. I am unsure about export outward to Europa and beyond; they might be happy pulling in the outer rocks or other asteroids.

UPDATE 12/26 Jacobi! Amaltheia's is -42.491, trying to get to the usual three (3). UPDATE 10/22/23: Thebe orbits further out, albeit a tenth the volume, so... start with that?

Did Fabio Costa solve the causality problem?

Nyrath is pointing to ScienceAlert updating "A Physicist Came Up With Math That Shows 'Paradox-Free' Time Travel Is Plausible". It's been two years but nobody has broken the Costa-Tobar logic yet. Google Scholar is pointing to twenty followups, none of which look like debunkers.

I don't think a time-machine can happen. I do wonder about FTL, though. One implies the other; causality is an obvious problem with time-machines, perhaps a non-obvious problem with FTL but still a problem whether or not you understand it (disclosure: I don't).

If causality has workarounds with explicit time-machines, then those same workarounds open a loophole for the implicit time-machine which is FTL.

Some followups

Shoemaker (following Crone) dismisses Heck's hypothesis of gold and even of copper from the Hijazi mines over the first/ seventh century. As far as I know Mu'awiya didn't even mint a gold coinage. But the amir did have copper - from somewhere. He'd conquered Cyprus 30/650ish so that's one source (classically). But just to humour us: has anyone tried a neutron-activation on the Palaestina coins from Jericho up the eastern Jordan to Damascus? Are they all Cypriot? Are they restrikes of old Byzantine coinage?

A lot of Cypriotes had got relocated from Cyprus to, exactly, Jericho and points beyond: Anastasius' Quaestiones 28 apud Hoyland, 100 says some ended up in Zoara. (Arculf apud Adomnán reports similar of Hamitic Sudanese.) Might some copper-mining experts have continued further...?

We agree: Safaitic was mostly graffit'ed by bored herdsmen showing off their mad skillz to other herdsmen (and occasional women). Then - per Hoyland "1997a" and per Whelan - the Safaitic / Hismaic secular graffiti (at Negev anyway) is replaced by Arabic-cursive in a "basic class" of monotheism and prayers-for-mercy. Some of these have a bit of Quran parallel but not a lot, until the Marwanids. If the Quran was penned to parchment before Muhammad, we'd expect - eventually - for the herders of that language to hear some of it. Shoemaker might not be looking for the Basic Class before the first / seventh century; Hoyland and Whelan are dismissed ch2 n93 and there's no Nevo anywhere. I actually think Shoemaker, by accepting Hoyland and Whelan, could have hammered the preMuhammadan codices harder - into atoms. Both of us would love to see any appreciable Arabic-cursive graffiti from that jahilya. UPDATE 1/6/23 - Fred Donner has tried. I don't think he has succeeded.

I should also like to know, on Shoemaker's behalf, on assumption preMuhammadan parchment MSS of Quran exist: where the beast was slaughtered. Obviously the Safaitic-authors herded sheep, goats, bovines. Shoemaker transmits Crone allowing some herding along the Hijaz also - by the way, there's my answer to p. 123 on the supposed expense of Red Sea papyrus, parchment would not be (relatively) expensive for Arabians. First: can we tell what the beast ate. Second: where are the west-Arabian tanneries? Why don't we see some Christian or Jewish scribe mentioning this strange new prophecy before the Didascalia / Doctrina of Jacob? It would be notable, to them, if suddenly Arabian vellum was getting expensive because new holy texts were brewing, nu?

To Shoemaker's comment on how the "Quran" didn't always bear that name, with hamza or no, one could add that Christians knew the Muhammadan book as "Furqan", or maybe as several books plus "The Baqára" - come to think of it, I remember Shoemaker, 49f noting exactly this of the bovine text, from Matthieu Tillier and Naim Vantieghem (n.33, misspelt). Here I think Fred Donner could have helped him out. Also if I may: I am unaware of Abu Musa's Lubāb al-fu’ād (Basrian 3araby may or may not have hamza) but we do hear of Lubāb al-qulub from Arthur Jeffery; "the core of the hearts", I think. There's talk that Ibn Abi Dawud thought this was just a copy of Ubayy's mushaf but Jeffery's summary hints at more than that. In fact it's a primary for Jeffery.

Shoemaker against the independents

Stephen Shoemaker entered our radar with "Christmas in the Quran" which was a sleeper-classic, breaking out into the mainstream in, exactly, an Ibn Warraq book - of that title. Over the past decade Shoemaker came out with The Death of a Prophet and The Apocalypse of Empire - the latter of which should have been a classic. Let's read Creating the Qur'an.

Shoemaker's prose-style was never top-tier; Creating the Qur'an has similar issues I'd had with The Death of a Prophet. Much ink is flung at other scholarship, Nicolai Sinai's work featuring as a particular foil. And there's this p. 83, which I cannot pass over:

... some scholars, particularly those who wish to maintain the traditional Nöldekean-Schwallian paradigm, have sought to dismiss any results that do not conform with this paradigm as resulting from improper analyses by these labs—notably, those at the University of Lyon and the University of Kiel. It is quite troubling to find young scholars, some of whom are not even trained in any field related to early Islamic studies, carelessly launching allegations about the shabby work done at these institutions with no basis other than the fact that the results do not agree with their presuppositions. One will find such comments mostly on social media, the use of which as an often uncritical, unreviewed, and unprofessional academic forum to disseminate opinions has become highly problematic. Islamic history should not be the product of social media influencers, regardless of their academic credentials.

On the one hand: I appreciate that Shoemaker is inside my tent, pointing his squirtpen outside. It's nice also that this para stands against Credentialism. But.

First off - here's a classic instance of Shoemakerian prose, repeating himself (dismiss any results that do not conform with this paradigm, no basis other than the fact that the results do not agree with their presuppositions). The term young scholars reads like ad-hominem. And I cannot help but feel like when he's blasting all "social media" that a lot of his ink is going to spray such allies as are doing work independently of the academy, perhaps independent for good reason. (Ibn Warraq is in the biblio offset from the other Banû as "Warraq, Ibn". There's no Robert Spencer nor Daniel Gibson nor even Yehuda Nevo.)

Chapter 5 narrowly approves Mark Durie on Qur'anic [sic] Arabic, with footnote 93 serving to distance Shoemaker from Durie's assumption that all Qur'an should be ascribed to Nabataea - which footnote and which distancing I endorse. Although: I will say that Shoemaker even by his own criteria could have taken time over Durie's thesis on what the Arab leadership might have believed before the Quran. However independent is Durie, Durie did get this one published in an academic press.

Late to the party

I had some giftcard at Amazon and I'd been meaning to buy some, you know, books with it; but it took until the Advent season before I thought of using any of it. One was Shoemaker's Creating the Qur'an; another was Spencer's Critical Qur'an. Both with hamza which, van Putten and al-Jallad will tell us, we shouldn't do, unless we're 'Abbasis.

Spencer (discounted) will arrive maybe New Year. Shoemaker showed up here last week and I have read five chapters so far. Meanwhile Shoemaker has offered the book, um, free. I'd downloaded this 5 November but, I dunno, why not slip $35 his way; at least I get something I can drag to a bar or to a restaurant or just on a walk. I'll keep the pdf for this computer - such are better for word-search than are indices; always a pain to compile, to edit - and, for the reader, to use.

By waiting this long (by accident) I did get a discount for Spencer's work. And at least I am getting these books, which I wouldn't be getting for Ibn Warraq banned by Bezos.

Before an Amazon review, assuming I do one, I'll comment on specific aspects tonight and on following nights. DONE 12/27

Frank bar-Abbas

Father Frank hoped to be a saint but Mr Pavone won't be a priest. If, like Shenoute, your credo is N THE GAR ETE MN MNT-LESTES SHOÖP N NETE OU-NTAU IESOUS HN OUME; you have asserted yourself a λῃστής. You might take a cross, but not the Cross.

It is one of those Hobbesian rules that if you serve in a hierarchy, where you have problems with the hierarchy, your avenues for forcing changes in that hierarchy must start with speaking to those within the hierarchy. The Catholic communion, to which Frank still belongs (defrocked but not excommunicated), already does activism. "40 Days Of Life". But more the Church (here including all the orthodox, not just in Latin) does aid; crisis pregnancy, relevant here.

In all P. Frank's theatre, how many lives did he save? I'll concede: some. There are bishops as sympathise with this totalism.

But Frank's bishops had to ask: how many souls did he lose? How many outsiders did he provoke - how many innocents did he expose? Our appeal is becoming more selective! - said the Essenes.

"Lapsed Catholics" (and lapsed Christians) will produce more abortion-attempts, and - above all - more general apathy toward this world as it is. Life has not been served, by Frank Pavone.

Frank Pavone should look into his own soul and consider how he might best serve the cause. Bishop Joseph Strickland may have to do the same.

CALLED IT 11/11/23: Sigh. Pray for the Bishop; I understand he retains episcopal charism(?), if that be the term, but he has no see.

Electric slide

Suppose we get electric cars with quick-recharge and long life for the weight. What are the implications of raw power?

Apparently - I didn't know, not owning a Tesla (yet) - these suckers can pack on some impressive G. I'd thought hotter than a gassed lambourghini was a meme.

I'd also thought the battery wasn't running a Hummer frame, given the energy it would need - and given that the battery adds a lot of mass, itself.

Isn't this just an argument for regulating SUVs, though? This was a deal we'd already made: upper middle class kept their SUVs, if the lower middle class was forced to buy car-seats.

The Laplacian space-station

TOI-1136 and Kepler-90 (and Hyperion) suggest that, if the gravity isn't too bad, one could squeeze a 4:3:2 stable-orbit space station between binary-resonant planets. Like: between Gliese 1002 b and c, if you don't mind the 15.8ly walk. Or: between Mimas and Tethys, or Enceladus and Dione, or pretty-much anywhere around Uranus. Let's talk betwixt Europa and Ganymede.

We should be able to find "Hill Sphere" or "Hill Radius" +Ganymede on the internet like Bagenal and Dols offer for Io but feh. So I'll do it: wedge this between Ganymede 1070400-31717 = 1,038,683 km; and Europa 670900+13652 = 684,552 km, from Jupiter's barycentre, by calculation. That's 300,000 km of space between; plenty of room for a Hyperion-sized O'Neill with rubble-shield.

Between 3.551181 days and 7.15455296 days, 4:3:2 suggests 4.7349-4.7697 days. What's fifty minutes between friends? Laplace has a better equation for 4:2:1; papers exist also for Kepler-90def. But this is a blog, not a physics seminar. 4.75 days it is (UPDATE 12/24 almost!). With a Keplerian mass 23959722339086384: semimajor is 814622 which I'll round to 814600 814216 km, 30° behind conjunction.

There's nothing there now which I must ascribe to the tidal-forces of Jupiter and Io. Hence the bounds around the period and meanmotion! But the stationkeeping shouldn't be godawful, within the limits of docking craft and launching them.

What would we get, playing middleman (well, 42%-man, lagging) here? At the very least here's the rescue-station for inadequately-propelled shuttles between Ganymede (which I shield) and Europa (which Twitter people tell me is shielded, but I'm not betting on it). By "inadequately-propelled" we can start with Hohmann; and we're told of even less delta-V options, on account Jupiter's is a multibody system, not just three-body.

For la Maison de Pierre-Simon other options include communication-relays. 4:2:1 systems mean that one or the other might be at Jove opposition at the same time the other two are in conjunction. And - since these moons are rotationally-locked - the Jove-facing side of an inner moon will not be able to talk to the outer moon(s) at that conjunction. Maybe the relay is not light-focusing at first but as noted, we got a lotta space-between.

Politics politics politics! This is the spot for Europa/Ganymede diplomacy. Also for high-G training if these two moons need a coördinated response against Callisto and beyond.

As for keeping the lights on: Some tidal heating might help keep the inner parts physically warmer, like under Europa. The ionic wind can work for additional energy-generation; both will supplement the Sun, weak out here.

Kepler-138f?

I couldn't find the PDF for Kepler-138 but the Wikipedians did offer up the vital-statistics: 10.3132068, 13.78110882, 23.0889203 days. And maybe an e at 38. That first one is running faster than 5:4 11 days; it's the local Amalthea, doomed, so let's ignore it. The latter are near-1:2:4. Mass detectable down to 0.187. LET'S DO DIS

Since these are edge-on orbits all over 88.3° I assume we got nothin' between c and d. Let's posit our e at, oh, 85°; a little inclined, as Venus/Earth, just enough we'll likely not see its transit. The equation is, as always, n_c - 3n_d + 2n_e = 0. In degrees/day n_c = 26.122716589941273 and n_d = 15.591894091297114. n_e would be 10.3265 °/d, orbit 34.86 days. Ohhh kay... this looks close to the 38 days what they'd "inferred" of e . . .

We do not, here, own a true resonance; it looks more Uranian than Jovian. It goes similar for the mass-ratios: the planets c and d may (may!) be twice GJ 1002's b and c, but their star is quadruple and, accordingly, everyone is about twice as far. (Probably why nobody's said anything about the resonance.) The tides don't much help constrain evolution, here; c, d, and e should be going out together as b goes in and suffers its own tides.

I do note the eccentricity although Earthlike for c (0.0110) is getting higher for d (0.027, ish). Compare Mars 0.093. Sometimes this implies we're missing a planet on the inside but I'm not seeing K-138 has the space for it. So let's rethink e - let's rethink bigger.

Would this blog be far out of bounds if it proposed a Jovian out there, maybe a Neptunian closer? At double-digit parallax we'll not see it directly. This should however be detectable by the radial method, after a couple of years.

GJ 1002b used to be resonant with c

Now we've got some basic Gliese-1002 parameters, and since my maths aren't professional-tier, I'm wondering if I can just cheat. Like: who else has done this stuff before me. It's worked so far on Venus/Earth cyclers; and on magnetising Ganymede.

I started with that 1979 classic "Melting of Io by Tidal Dissipation", which show us the stakes of the game. This assumed Sinclair 1975 on the triple-Laplacian around Jupiter and, it turns out, Uranus. Now: over GJ 1002, we only have the two planets - the astronomers had the 'scope only for long enough to find the 20-day rockin'. In fact we're here precisely to see if there's that third, 40 days or maybe 30 days (inclined?) or I dunno, 80/3 days.

Sinclair linked in his turn to Greenberg. Good news: Titan/Hyperion, a two-body resonance. Bad news: they run 4:3, and Hyperion's mass might as well be zero. In fact now that Cassini's seen Hyperion, we know that the thing tumbles chaotically. More relevant to us is Sinclair 1972 on Enceladus:Dione and Mimas:Tethys, both 2:1.

Sinclair posted an equation for the change in mean-motion over time: dn/dt = -27n²m/4Q a⁵. Take planet b as it's closer so hits harder. n_b = 34.79572°/day. m and a are ratios, mass and radius respectively. m_b = 2.7031e-5... divided by sin i. We know even less of the radius although I'll assume a Venerean density as to force a radius about Earth's. Since 0.137 R_☉ = 14.933 R_⊕ we'll set a=0.067.

So, er... Q. That's the tidal-dissipation function on the star. I don't think we've studied the tides on that star yet.

Luckily we have similar for Io upon Jupiter. This argues that the tides which Europa and Ganymede raise upon Jupiter are strong enough to pull, in turn, Io backward. Eventually Io's mean-motion increases as the other two decreases. The planets are in resonance now but, eventually, Io will break from it.

Taking that to GJ 1002, the star unlike ten-hour Jupiter is rotating many days behind its satellites, and most of us assume this system is coplanar. The star's tides should be pulling b inward to a faster spiral - and a shorter day. b's own tides should lower it too, as for Phobos. The Deimos of the system, which is c, takes that energy, to rise and to slow. That is what we see: b's day is already shorter than half c's. 2:1 resonants are supposed to be unstable anyway on their own; Kirkwood Gap, anyone? I wonder how long it's been drifting?

Last night I'd intuited another planet to clean up the Laplacian. Interjecting (4:3:2) a 13.8-day planet c would do it, pushing their c to d. The new c would be 0.055 AU, so an Earth mass (maximum) would reach 0.001 to L1/L2. This is, inclination-willing, within our bounds. 4:3:2 is not the problem; we allow it. The problem of course is that we saw the actual 20.2 day c, and didn't see this 13.8 day c-postulate. Also they say that 4:3:2 implies a giant planet or at least a lot of Kepler-90g/h which, for GJ 1002, we should have detected since 1995. Anyway this wasn't even my initial thought last night so I shan't think further of it today.

More serious would be something with longer-period so harder-to-see, n_b - 3n_c + 2n_d = 0. So, n_d in °/day is 16.14287057256621 / 2 = 9.3264. This would be a 38.6 day orbit; a little inbound of double c's. Mind, the tides this sucker would raise on its star would simply add to those of c, pulling b even further away. But maybe not just yet.

Either way that's yet another constraint on anything beneath b. Nothing below b owns momentum enough to raise b's orbit. In fact it's likely b and c both have driven everything down there into a fiery grave by now.

Gliese 1002

h/t Nyrath the 1002 entry in the Gliese catalogue has planets. Two of them - Earth-sized (at least), habitable-zone. This star has a whopping triple-digit parallax setting it at a mere 15.8 light years away.

These were found by Canary Island 'scopes, hence the peacocking by the IAC. Gliese 1002 is dim, weighing in at 0.120±0.010 M_☉ (39954 M_⊕). It is no flare star, either; which was nice for the observers. They assume older than Proxima 4.85 Gyr.

Springing out to me, the planets run in a 2:1 resonance like Io and Europa, like Europa and Ganymede. Inner planet goes around ten-ish days more precisely 248 hours and maybe ten minutes. Compare Io 42.5 hours - so, b takes 5.839 times longer than that, more like a Ganymedean orbit.

But the innermost's 10.35 days doubled doesn't quite hit the 21.2 days of the next one out. The mean-motion equation n_b - 2n_c is, in degrees, 360 / 10.3461 - 2 * 360 / 21.202 = 0.83666 °/day; compare Io/Europa 0.7395 °/day. Although it's less a proportion of n_c = 16.97953 °/day than what Io/Europa got against Europa. I'll get back to this.

These aren't transits so the masses are minima: in from out they are 1.08 ± 0.13 M_⊕ and 1.36 ± 0.17 M_⊕ sin i. Mass-ratios against their sun would be 2.7031e-5 and 3.4039e-5, a reverse of the Io/Europa range 4.497e-5 and 2.536e-5 (respectively). The researchers aren't hazarding inclinations relative to Earth. I'd hoped we've the stellar inclination, for a red-dwarf, but nobody's bothered measuring GJ 1002's. Although they did get a rotation, 126±15 days; implying the angle isn't too edge-on.

So I'll papernapkin this, with Hill Spheres. Based on that Keplerian mass a³/T²= 8.9416038541891E-07, our boy Johnny says 0.0457 AU and 0.0738 AU (again, no direct imaging). If they were edge-on 90° to us and if the errors be all zero, which they are not, the zones-of-influence are 0.00095 L2 against 0.0016 L1. So: the outer planet reaches only to 0.02715 AU. That is: boosting the latter to 6 M_⊕ (sin i = 1.36/6; i = 0.2286539 rad = 13.1°) would overlap its L1 into the inner L2.

Personally I doubt we're expecting 13.1°. It's all more likely less perpendicular to us.

The planets' rotations've got to be tidally-locked, both of them.

We don't know if Gliese 1002 hosts anything as rocks a five day orbit, or 20/3 days. Mind, for any such conjectures we must impose mass constraints. I suspect such would have shown up in the data unless it were very much less massive than the other two.

REPOST: I'd done a lot of it yesterday evening but, on further review, the title and conclusion were too unfocused. Here's the new followup.

IT'S COLD OUT THERE 2/18/23: The inner planet at 67% irradiance looks Huronian like Wolf 1069's, albeit maybe rockier. The outer one at 26% is a superCeres or even Hycean.

The circumference of an ellipse

Looking around mathematics this time, I found a 'tube on the circumference of an ellipse - also called perimeter. There's no equation for it! Instead I found a power-series.

The story is an ancient one - differentiation is easy, integration suuucks. Famously there's nothing for the Euler–Poisson integral, the area under the Bell Curve. We want $\int_0^{2\pi}\sqrt {a^2\cos^2\theta+b^2\sin^2\theta}d\theta$. Well it turns out that Johnny Kepler wanted this too and didn't get it. Although, yes; where there's an algebraic powerseries there's an integration for that powerseries. Approximations therefore exist, all multiples of π. Mathematicians enjoy Ramanujan's.

I wondered if C# libraries had anything on ellipses, you know, to save us some time. We do have DrawEllipse... in the Graphics library (Common dll), and Ellipse in Shapes (PresentationFramework dll). Both are visual; neither is Math. Also I'm unsure if anyone's given us something down at the CPU.

Looking into the series for the ellipse-circumference, one happens to own a lot of binary exponents. Coincidentally we've just done some.

My starter-class in C# is

    internal class Ellipse {
        public double h { get; private set; }
        public double major { get; private set; }

        private static int[] binCoef = { 1, 1, 1, 25, 49, 441 };
        private static int[] shifts = { 2, 4, 2, 6, 2, 4 };

        public Ellipse(double a, double b) {
            var minor = a - b;
            major = a + b;
            h = minor * minor / (major * major);
        }

        public double Power(int accuracy) {
            double res = 1;
            double multiplier = 1;
            int denominator = 1;
            StringBuilder sanity = new StringBuilder("1");
            for (int i = 0; i < accuracy; i++) {
                multiplier *= h;
                denominator <<= shifts[i];
                sanity.Append($" + ({String.Format("{0:0.###}", multiplier)} * {binCoef[i]}/{denominator})");
                res += multiplier * binCoef[i] / (double)denominator;
                Console.WriteLine(sanity.ToString() + $" = {res}");
            }
            return res * Math.PI * major;
        }
    }

Before I'd ask for RUST, I can already see some areas of slowness. (Besides the debugging-code.) Like: instead of looping through the arrays with that integer, maybe we can pluck the values with a pointer. And that division by the denominator, which denominator has to be turned into a double... ugggh.

Probably better to store binCoef[i] / denominators[i] as majick-number doubles in a single array; to remove the "denominator" and his bitshifts. But then it would be harder to read.

Alternately...

        public double Power(int accuracy) {
            double res = 1;
            double multiplier = 1;
            double multiplierLog = 0;
            var mathLogh = Math.Log(h);
            int denominator = 1;
            for (int i = 0; i < accuracy; i++) {
                multiplier *= h;
                multiplierLog += mathLogh;
                denominator <<= shifts[i];
                var oof = multiplierLog + Math.Log(binCoef[i]) - Math.Log(denominator);
                res += Math.Exp(oof);
                Console.WriteLine($"{ multiplier * binCoef[i] / (double)denominator} or {Math.Exp(oof)}");
            }
            return res * Math.PI * major;
        }
    }

Here I'd magic-up Math.Log(binCoef[i]) - Math.Log(denominator). The remaining pain-points are mathLogh and (more-so) the repeat res += Math.Exp(oof). Hence the oof. But. If that Log's base is two(2), we might get away with the Evil Bit Hack.

Now: do we need fast-calcs of ellipse-perimeter? I somewhat wonder. For a friend.

Kepler-138's two steamworlds

This came up from Montreal (and ScienceDirect) yesterday: a presumed waterworld (or two). We're already aware of Quebecois water-dense worlds elsewhere so I'm more interested in how they found this one.

Kepler-138's system was found almost a decade ago by a transit-detecting telescope. The star has another double-digit parallax so 218 lightyears away. Transits numbered three here... directly.

What happened recently was the discovery of a Callisto, as it were; a fourth world as didn't match the other, inner three. 138e does not transit. So it is constrained only in its minimum mass... and an estimate on inclination. This outer planet did however force a recalculation of the inner three. Mainly of c and d; b is solidly a (hot) Marslike.

K-138c and 'd are still too hot where TOI-1452b is likely liquid. But all are now slated as low-density. For 138c and 138d they figure: steam, maybe supercritical below the steam, hot ice below that.

Carbon-dioxide and carbon-monoxide would also be low-density so Zim remains unsure how they figured these two Keplers as steamworlds as opposed (say) to carbonworlds. Same for TOI-1452 now I think on't.

Q_rsqrt

I stumbled on float Q_rsqrt(float) on some youtube or other. It is the reciprocal square root; done especially to normalise a vector to unit-size (Pythagoras, yo!) This is much-beloved of ray-tracers in such games as use the Quake III engine. Like “Alice”.

The mathematician in me agrees to use the word “reciprocal” against “inverse”. “Inverse” implies the inverse-function which for a root would be the, er, SQUARE. The insolation h which various planets at a AU get from the Sun tends (as the sun's disc recedes to a point) to reciprocal-square, k/a²; k, at this blog for 1 AU, being 1361 or 1380 W/m² or whatever. We’re talking the reciprocal-root which, for this equation, would be the true inverse. It’s how we’d figure a: √[1361/h] = 36.89/√h. So: “inverse” is meta, “reciprocal” is functional.

Getting /√ (or ^-.5 for us oldschool Microsoft nerds) is slow. I don’t care if I’m only doing this to get a one-off calculation done; but gamers care, because they’re trying to shoot a demon around a corner, not do a lot of trig. The Napier family would suggest we stuff the memory-card full of natural-logs and do a lookup. I understand that’s how computers generally did the Long Division and various roots: you’d get arbitrarily-good accuracy, dependent on that memory-card. In the 1990s power and memory both were lagging.

As to how the lookups were done; maybe binary-search O(ln n), to get a double-precision number into a less-precise bound for the lookup. More likely they just chopped it to something as could get mapped in a few hash-iterations to Napier's table. This post doesn't much care.

“Luckily” the graphical resolution of the day was also poor. Monitors were predominant CRT anyway so few cared about the resolution; especially if frame-rates be quicken'd enow to skip past notice. Some programmers wondered if they could get this all done faster than the lookup toward a memory-hogging table, with an acceptable trade in accuracy.

More-luckily it happens that a square root is base two. We're on a computer. We're binary.

So here’s the basics, for that incoming four-byte signed floating-point number. You set a local “y” to that. You then pluck the binary out from the pointer, you C monster you:

let i = * ( long * ) &y;

Turns out, that's log₂y. Then comes the literal WTF - 0x5f3759df - ( i >> 1 ). That >> is a binary "rightshift"; chopping by factors of two is what computers do. So this just represents WTF + -log₂y /2. As for that hexademical WTF against which this halved integer has been subtracted ... we'll get to that.

After reversing the resultant integer for the new y = * ( float * ) &i; it turns out not to be perfectly accurate. Thence you run some newton-raphson and GTFO with it.

We somewhat cheated: we could have started with almost anything and done the newton-raphson. But the need was for speed. You’ll be iterating that last as few times as possible; no for-loops or bounds-checking here. In the latest 1990s, they did it once, with a second run commented-out. Since then the algo has been put into instruction-sets so that the PC can do this closer-metal: rsqrtss. I wonder if System.Numeric’s Vector3 (float-based) is using it...

With our better monitors, which will show you double-point precision, Toru Niina has reported some sketchiness in practice; and our memory and RAW POWER are better too, so Napier isn’t looking too bad anymore. The fast /√ may not have lived very long, mid1970s-mid2000s if we're generous; but - like the span of Pluto inside Neptune - that's most of my life. [WHY NOT 9/29/23: Compilers don't assembler anymore.]

Toru Niina hopes to salvage this lost spark of Clinton-era genius. His perhaps-obvious first-pass was to implement that second newton-raphson, in RUST. But this slowed down the process such that it no longer competed with the old 1/sqrt(x).

Alternatively given a limit of one newton-raphson spin, we continue that arcane-art of picking the startpoint. That’s a tweak to the WTF hexadecimal 0x5f3759df. Consensus runs that it be too low, with alternatives ranging from higher 0x5f375s even to low 0x5f376s. But never mind all that: why were id software ever using signed LONG and FLOAT? Square-roots don't do negatives. Make them unsigned, double your accuracy. Post-Pentium, when "long" isn't Int32/4-byte but Int64/8-byte, a "double" of 8 bytes should be as fast as the 4 byte "float" once was.

Antihelium

We've had muonic helium; now it's the turn of antihelium. This is two antiprotons, with an antineutron or two to keep the strongforce strong.

I don't know if anyone has attempted making antitritium to let it decay. Antihelium doesn't decay... until it crashes into normal matter. Also: an antihelium ion should be negatively charged. Anyone try sticking that onto an ion like, er, helium?

The finding here is survival rate. They used the Large Hadron Collider at CERN, hadron-subset of Ions which name can be massaged into "aLICE". By pounding Hydrogen-1 - that is, ionic protons - at Lead-208, sparks fly of energy, and some sparks become antihelium. Then Alice sees how long those new ions last before they hit something else and go blooey. This allows for direct measurement of antihelium transparency: a unit of measure for the number and energies of antinuclei.

Ultimately the hope is to constrain antihelium from cosmic rays, always nature's highest-energy particle-accelerator; against antihelium from darkmatter (if it even exists). The latter should be slower-energy.

TOI-1136

TESS the transiting-planet scope found an object of interest around the Praesepe cluster 276 light-years off, so within that (low) double-digit parallax. There's arXiv for details. h/t Planet B's NASA writeup

The planets are all transits so they are all very close to the star - which is pretty-much our own Sun at 700 million years old (1.022 ± 0.027 M_☉). So the planets are all horrible.

Of interest to me is firstly the planets' resonance - there is one, there might have to be one, as close to the star as they are. But it's not as Laplacian as those of TRAPPIST or, er, Jupiter I-III. Remember that it's all still young, if 100 My older than Kepler-221.

Their masses are estimated by transit-timing-velocity. Not radial-. As they note, radial has a bias toward high-mass for the radius i.e., high density. Until we get to 8 M_⊕.

Fig 17 shows the masses and radii. Logarithmic scale - this to include the Neptunians at <20 M_⊕. Error bars are high; so they didn't bother giving us a numeric table. Japanese wiki says total mass: 35.51 M_⊕ which is slightly more than Uranus+Neptune together. Gliese 876 b is 2.66 M_J. Innermost b is as dense as water; that’s the densest.

How did all these form separately rather than coalesce into one big ugly Hot Sub Saturn. To that their system seems near-perfect: no perturbations from the other Praesepiae.

Tidal energy is a demonstrable Thing for Laplacian worlds. This is estimated at 1e+16 W for planets d and f (implicit). Planet d is getting 1e+20 W “bolometric”, which must mean calculated from the bolometric luminosity (effectively solar), inverse-square planet-distance and (I think) integrated over surface-area which for order-of-magnitude can just be πr², 156.75 times that of Earth. Anyway the tides are negligible relative to raw sunlight.

“Solar-constant” insolation over here is, as this blog keeps repeating, 1380 W/m²; but sometimes they lowball the total 1.74 e+17. Anyway: 1136d is getting three orders of magnitude more sun than we get.

Compositionally I suspect our “water density” baseline is the Hot Ice: VII at 3+ GPa, under a superheated liquid-water ocean. The authors cannot account for this for the planets c-on-up, so propose further envelopes of hydrogen (even helium). As for b that’s puffy rock since it’s not pushing tides against the other planets.

Even then, d and f look too puffy and might contract in future. The authors request more time from the JWST because of course they do.

The article posits (over and over!) that planets e and f, at 7:5 resonance, will likely not stay there. One or both of these will find its way out - or in. One might see a Theia opportunity in this system's future especially if perturbed. If not the authors muse about near-resonance, like Earth/Venus or Saturn/Neptune.

Also here is disc density, within 1 AU anyway. By extrapolation the system has already sucked up available material in its habitable-zone, so has no Earth. I can’t see this system tossing an Earthlike into that region either. But I’d not rule out more super-earths or ice-giants 2+ AU (which we’ll not see from here).