That's a spicy meatball

Lucas Beveridge is talking about something he and Sam Piper did for Atomos Nuclear and Space. Suppose we only shipped one reactor to a HEO. That reactor hands over energy to tungsten plates - one per mission. The plate then delivers the kilowatts. Here's how it was tested; here's what was tested.

At HEO - as in, GEO or higher - you can fuel up a lot of space tuggery. Take Tory Bruno's Blue Ring, which needs one tonne of xenon for four of payload. That reactor looks like it would in fact deliver the 5.5 kW needed to propel to Gateway's lunar NRHO. To get a mission rolling "for weeks or months", Beveridge prescribes Scandium-46 with its low 84-hour halflife. Maybe tugs; maybe Venus injection. Sc-46 is allowed to deorbit after three years.

The test used Manganese-56 which decays in 2.6 hours. This can deorbit rather sooner. Maybe use the Mn-56 for high-thrust tugs between HEOs and be done with it. Like if you just want to hit the Spaceline cable at the 80 Mm this blog has promised.

Naturally none of this is to run on Earth (the least radioactive Co-60 is legendary). The idea is that the reactor - which is way too high up for Earthlings to care - creates neutrons, which then irradiates the neutral cobalt or scandium. The hot stuff, in turn, rams gamma (and not more neutrons) into the metal plate, which then heats up. Or maybe just heats up some beryllium, which I'm seeing recommended for high-enthalpy rockets for Martian landers.

For longer missions, he's talking Cobalt-60 at its 5.27 year halflife. Beveridge is suggesting this for a Uranus orbiter, or series of orbiters. First it has to get there but we can probably do that with a Starship. And/or with a fusion-driven ship launching off Deimos.

The asteroid/Martian economy

Mark Thompson last April relayed a Swiss(?) study by EPFL on how to deliver materiel to Mars (to its well, anyway).

Serena Suriano, Shamil Biktimirov, Dmitry Pritykin, Anton Ivanov seem to be picking up where Zubrin left off; they're not stopping at Deimos (like I'd stop). Except, Zubrin wanted Martians to mine the 'stroids and these three Russians (and one Sicilian) are asking the Belters to do it themselves and sell to the Martians.

To read the article, they want to deliver the goods to a Low Mars Orbit 500 km. Phobos, for reference, is at 6000 km. Why not just send it all to Phobos? Gravity there is higher than Deimos' and this place should be able to dangle a tether to 500 km.

On the Earth side, all this assumes a depot at STL2. That's "ST", not "TL". Somehow they have to stationkeep that.

The 'stroids they want are metallic, like 332 Siri. Guess they want the tungsten... or Beryllium. That one sails out 2.7 AU where Mars is, what, 1.6 and Vesta 2.36.

But... isn't Mars literally littered with meteorites of all sorts? If it's volatiles you want, just drill for the ice. And if we're staying at Deimos (or Phobos), it's probably mafic such that there should be a few iron and siderophiles right there. Or anyway sicila fit for anhydrous glass fibre.

NASA's new tungsten mine

There is, today-announced, a vast tungsten reserve in Nevada. Tungsten as you know comes with other essential elements like boron and lithium. Some of the land however overlaps with 17 square miles of NASA. NASA say they need it.

My suggestion is for NASA to earmark a tax on the land they've inherited. Materials from that part of the land go to NASA as first-choice customer, for NASA's own use.

Meanwhile I guess NASA should calibrate its satellites elsewhere; the Feds can scout around for other parts of its enormous Southwestern lands for anything likely. Southern Cali? Utah?

BAqDAyT 8/7 from Stephen "Vodka" Green.

What was wrong with the Sack of Troy?

One of those prefaces to The Odyssey is The Sack of Troy, summarised here. In antiquity, most agreed that Homer didn't write it. It tended to be attributed to fellow Milesian, Arctinus. Aristotle wasn't complaining about this one particularly when his Poetics lambasted the likes of Cypria for being Just A Bunch Of Stuff That Happened unlike Iliad, which promised a theme and, he thought, held to that theme, this-or-that chapter aside.

But even if Arctinus wasn't Homer (some today doubt Odyssey was Homer)... Hesiod wasn't Homer either. And what Proclus and others claim of The Sack of Troy is that it is in fact restricted to a single episode, after the Horse. So Aristotle shouldn't have minded... right?

Giampiero (or, Jean-Pierre) Scafoglio has an essay, "Two Ways of the Epic Genre in Late Antiquity" discussing the Homer / Aristotle reception in works such as Triphiodorus' epic about the "Capture". This epic, you can read today. And this, wikipedia is saying a lot of authors did read. Latinists of course are aware of Virgil in Aeneid Book II covering the same episode, but self-consciously a preface to the epic of Rome to come.

Triphiodorus clearly didn't think Arctinus got the job done or he'd not have bothered. I do not see where Triphiodorus chose to rewrite a "Wrath of Achilles" or "Tragedy of Hector" (there's talk he redid an Odyssey however). Our man may have been right, given that I cannot link to a full Arctinus. As of this decade the 2020s, it looks like the Sack was no longer even in the late-antique libraries (pdf)... which puts Proclus under suspicion as well.

What we can do, perhaps must do, is to compare Triphiodorus to his peers and middlemen.

Against Virgil, our man chooses Cassandra over the other prophet Laocoön. For the great tragedians, that's Aeschylus over Sophocles. As a narrative choice in a postAristotelian epic, Laocoön doesn't work here and he's also not in the two Homerics. Arctinus did note that the gods chose now to knock him out, but this episode serves mainly to get Aeneas out of the city before all the fun starts.

Triphiodorus and Virgil do seem to agree on Sinon. Also Triphiodorus agrees that Aeneas was at the sack so tacitly sides with Virgil against Arctinus here.

Ultimately, Triphiodorus feels like a writing-exercise. He seems to be showing that he can write a "Sack of Troy" as might meet Aristotle's rules, if not his approval - because personally I doubt that Aristotle liked writing-exercises, of which a lot of those elder-epics smell. Virgil on the other hand wants to bring us into the Trojan side as to see the full iniquity of the Greeks' crimes. Like Nolan this year, Virgil has a point.

Going back to Arctinus: if I was doing a writing-exercise in years B.C., I'd play up the glorious deeds of the Achaeans sacking this city. I'd tick the boxes of the Homeric heroes in Troy meeting their own ends and/or causing appropriate ends to other heroes. As to, why; because Miletus was precariously maintaining its autonomy against the Anatolian barbarians in Lycia, Caria and especially Lydia and, before that, Phrygia.

Yeah, Virgil probably wore it better.

BACKDATE 8/6

SDI's plasma-core rocket

In lieu of Cassenti's microfission-catalysis for fusion rocketry, for interplanetary missions Omira and Mourad suggest "plasma core". Interstellar is another matter (heh). So let's look at plasma-core. This is an idea from 1985 to power NERVA/NΘP.

The core is Uranium Hexafluoride, either U-235 or -233. In theory a Curium-247 hexafluoride also can be made. Anyway, UF₆ is a solid at reasonably-warm temps (<56.5°C). As a plasma the fluorine ions are likely more problematic but we're hoping to make a nuclear blast out of it so noöne cares.

In 1985 they were trying to contain a sphere of this plasma, swimming in a mutually-immiscible noble gas; and why not, in microgravity. They picked argon, probably-obviously. They measured 50km/s exhaust. We divide that latter by Earth 9.8 to make of that a ratio independent of SI or Freedom units, called Specific Impulse; 5.1 kiloseconds. (Although now it seems dependent on Earth being that frame-of-reference.)

They got it running for about two minutes. After that, they lost enough uranium that the critical-mass went subcritical. Also there won't be microgravity during the thrust phase. Before anyone could figure out how to make this practical for a space trip, after January 1986 the launch costs per kilogram hit the Challenger wall.

Spacenerd life is better now. But the middle-1980s flights of fancy have been forgotten... mostly.

Hence such fission pulse engines as in Howe two years ago, which promised 5ks specific-impulse which would have compared nicely with 1985. Or last year centrifugal NERVA... 1.8ks. They'd make it up in thrust though; so if they just wanted to push loads to Deimos or Venus rather than all the way to Jupiter, it might work.

Gerald Marsh seems unhappy with Howe and, more so, with that lumbering 1.8ks solution.

Marsh proposes to revive Ronnie Raygun's tech: with magnetic confinement, in a spheromak. Marsh seems an expert in magnets, working on them in 1996. Marsh must however conclude that one (not he) must also find a way to generate the plasma with the field configuration chosen, maintain thermal stability, and find a way to turn the rocket engine off; opining these are non-trivial engineering problems.

I counter that turning the rocket off is the least of this rocket's problems. What you do here is to calculate the cooloff of the rocket and let the spacecraft reduce its acceleration naturally. It all gets tested in the field like SpaceX tests its Starship. If you're asking after an abort sequence then whatever, just separate your craft from the engine and push the still-running engine to the side as it makes its own merry way to the outer AU fringe.

BACKDATE 8/5

A proposal for the House of Representatives

Cambridge University is, presently, a disgrace and one excellent reason for its disgrace is politics. So, sigh, let's listen to Cambridge on politics.

Britain (not part of the EU) runs on the DSA system. It has a Parliament. The majority of Parliament votes for a Prime Minister, even if the people didn't want it. Margaret Thatcher was the Prime Minister throughout the 1980s. To her, is attributed the comment "we have an elected dictatorship". However you think of Thatcher or, if you're DSA, Burnham: I don't think Thatcher ever cracked 50% of the popular vote and we jolly know Burnham hasn't.

Similar has happened to Denmark. Frederik Ravn Klausen, who sounds like a Scandinavian, nonetheless works out of Cambridge (he should leave); he has teamed with Sebastian Tim Holdum in Copenhagen. They propose instead "geographically ranked guaranteed proportionality". Buroughs / ridings / precincts / parishes still exist. But the election winners are chosen by popular vote. So if your Albertan ridings (screw it, let's be Canadian) voted for the Tory, and everyone north and east of the Lakes voted for the Grit; the Grit votes override most of you. Some of your Tories will get through however. From the truest-blue ridings.

As they note, regionality is here sacrificed. It rather has to be, because someone Federal (or Royal) is going to have to guard the ballots wherever the score stands to be run-up. Historically the cities.

An expressly-regional second chamber would counter this. Americans have such a body: the Senate, wired into State boundaries and once-upon-a-time appointed by State legislatures. This is why Americans deserve to take Klausen-Holdum seriously where, frankly, I would never recommend the above system for any unicameral state. Fer cryin'-out-loud, Denmark is made of islands (and a peninsula).

Drawing up the constituencies is still up to the States I guess. On the plus side, if their constituencies might get overridden by their neighbo(u)rs anyway, gerrymandering might not be as hot an issue.

The issue wot I see as hot is if these States' voters are overridden by other States' voters. They already have to suck it up when Senators from Delaware and North Dakota dab on 'em.

Pekah, Shalish of Israel

Pulu wrested the throne of Ashur in 745 BC, from a "Shalmaneser V" whom Pulu's family then disavowed. Perhaps similar breaks of memory were had in Israel at the time. So: Carl Lederer, and now youtuber "Dig."

The eretz-Israel had been a united land under Jeroboam II, but as all men do he died. His heir Zechariah was ousted in a coup and that coup - under Shallum - collapsed. Menahem and Pekah picked up the pieces. The Bible says Menahem ruled for ten years and Pekah for twenty.

The maths don't add up under scrutiny from Assyria however. Menahem gave tribute to "Pul"; that emperor claimed he'd had it from Pekah as well. Luckily, we have a local report: from Hosea the northern prophet. His sermons made a point of the twin iniquities of his land. Hosea didn't consider Judah in this calculus, despite that it was starting to matter again; Hosea's twinland was Ephraim-and-Israel.

According to Lederer's reading, Pekah had a base in Gilead and simply slipped over there, keeping that base. The face-saving fiction was that Pekah would hold the title "Shalish" and not "king of Israel". In practice, yeah, Pekah was sulṭan across the water, as it were.

I must inject here that per Rendsburg (pdf), Amos especially Amos 6 is also writ in a nonJehudi Hebrew to be considered northern. Amos didn't preach about Israel/Ephraim's twinship for the simple reason he preached under Jeroboam II when that kingdom was one. His kingdom likely included Judah then; maybe then Edom (so I'm not getting into which "Tekoa" here). So for Amos, Jeroboam's court was the court which mattered.

Pekah would eventually switch to being an ally of Damascus and make a bid to take Judah. Ahaz squealed to Assyria who then attacked and got all of it. Israel, from Samaria, would end up a rump and tributary Assyrian vassal, under Hoshea.