roystgnr
23hr ago
Musk posted about it last night:
https://x.com/elonmusk/status/1880060983734858130
But he's clearly identified a downstream problem there, not yet a root cause.
The booster landing again, in visibly better shape than test 5, was a win. The Starship explosion was grossly embarrassing (worst performance since test 2, and yeah it was a major version update but they obviously weren't expecting this level of new teething problems).
It was also a near-disaster: no reports of injuries, but (unconfirmed) reports of property damage from shrapnel, and aircraft having to do emergency diversions away from the hazard area, are not things that should ever be consequences of a launch failure.
And of course it must be investigated now. Starship is currently launching solely through a narrow keyhole between Cuba and Florida where any disasters can avoid the heaviest population densities, but there are still islands in the danger zone if, as just happened, a launch fails in an unrecoverable way at just the wrong time. More importantly in the medium term, SpaceX wants to start catching ships in addition to boosters, and for that to happen they first need to reenter, from the west, over land. If they can't credibly and correctly assure the safety of that plan, they'll be stuck at the same "partially reusable" design level as Falcon 9 (and hopefully New Glenn sooner or later), and the cost of that would that they're not recouping their multi-billion-dollar investment any time soon, and the harm it would do to flight cadence would make their Artemis plans much harder.
roystgnr
5d ago
Will they try to build more multi-family dwellings or just rebuild the mansions?
They'll try to build more multi-family dwellings, because density pays off when you start out with some of the most valuable land on Earth, and in the end they'll just rebuild the mansions, because the thumb is pushing hard on the scale for that.
Scott linked to a few studies a few years ago. Getting fluoride out of your water ranked at his 3rd tier of "obscure pregnancy interventions" to raise IQ, with very mixed evidence.
1mg/day is what you get from 1.5 liters of typical fluoridated water, so it was a significant exposure increase but not an order of magnitude or anything.
roystgnr
9d ago
If reservoir capacity was the problem, wouldn't we see the reservoirs drain, and then demand for water go unfilled only after the reservoirs were excessively drained instead of near-full? If they're not draining significantly away from full, then reservoir capacity cannot be the only issue; whatever problem is preventing water in small-but-full reservoirs from being used would presumably also thwart attempts to use water from large-and-full reservoirs.
roystgnr
9d ago
Most of my long-form reading in the last decade has been with my kids, and I think it's really highlighted the distinction between "leisure time" and "free time".
On the one hand, those hours (and others doing enriching things with family) have been some of the most enjoyable of my life, spent at activities of my own choosing, so how can I not call that "leisure time"?
On the other hand, up until I had children, everything I did in my free time was something I could start doing on a whim and stop doing on another whim and restart on a third whim. But in that sense, many of my leisure activities today are less "free time" than my actual job is - I have a great relationship with my boss and coworkers doing work I love, but I also have a lot of savings and a decent resume and saying "I quit" about my job would still feel less encumbered by obligation than saying it about e.g. reading with my kids.
roystgnr
9d ago
lamentably predictable results.
I personally wouldn't have predicted the magnitude of the results. I was imagining situations like "this year's rainy season was wetter than average and spawned too much growth, but by the time we get a months-long analysis done it'll already be the dry season again and it'll be too late until next year". Reality is "paying attention to particular seasons is pointless because the average time between the beginning NEPA analysis and beginning a prescribed burn is (pdf warning) 4.7 YEARS". If there's an EIS required then the lead-up to a controlled burn is 7.2 years. The NEPA phase of the delay is about 1.3 years in the average case and 2.5 in the average EIS case, but then there's more years of delay before the NEPA approval turns into forest service activity and more years before the treatment begins.
I do get that there should be some analysis. I grew up visiting Bandelier National Monument, where we learned from the rangers about how the old policy of trying to squelch every small forest fire had contributed to the undergrowth buildup that led to the devastating La Mesa Fire (fun fact: the fire only got to Los Alamos chemical explosives labs, and the nuclear material got lucky). But even after paying attention to undergrowth buildup, they still later had an equally large fire in 1996, a bigger fire in 2011, and most horrifyingly a bigger fire resulting from a "controlled" burn going out of control in 2000. It's really hard to keep hundreds of thousands of acres from occasionally becoming a tinderbox without preemptively burning a lot of the buildup in huge swaths, and yet it's also really hard to safely start and manage huge fires in an almost-tinderbox, and even in a location where the worst-case scenario is a radioactive forest fire we're having trouble getting it right.
What I don't get is how a years-long analysis could possibly be useful. The important timescales here are days and weeks (as weather conditions change), months (as seasons change), and decades (as climate and construction patterns change). Anything in the years-long category seems like it should be too slow to keep up with any of the former changes, in which case why can't we just just reuse the last scheduled-every-couple-decades analysis immediately upon noticing a problem, rather than commissioning and waiting for a new one? I'm a big SpaceX fan, and always tempted to unfairly rag on the FAA when they take months to approve a Starship test flight, but at least when they're slow there's always some flight change or prior-test analysis to justify taking a "long" time; the FAA has also approved a launch license almost immediately after the previous test, in a case where the previous test had no unanticipated failures and the next test wasn't adding any massive changes. Is that kind of turnaround just completely unimaginable for environmental review for the Forest Service?
roystgnr
9d ago
I have forgetten most of them
Have you forgotten what they taught you, though? I find with a lot of non-fiction I lose episodic memory of the book but I retain semantic memory of much of its theses ... which is really the right subconscious prioritization, I think. I find knowing assorted facts/theories/hypotheses useful far more often than I find knowing where I got them useful, because even when I need to look up a reference I don't really care that it be the same reference. And even the parts I forget are often things like supporting arguments that still served a value by indicating whether I should consider the central arguments worthwhile.
Additionally, a ton of books could have been an interesting blog post series but they've been puffed up and watered down to fill a 300 page book with a dumb title.
This is definitely true, but I'm not sure whether it's a bigger waste of time to have to speed-read through such books' puffery or to have to search through a bunch of uninteresting blog posts to find the most interesting ones. Publishers' selections aren't a great filter, but so far social media isn't either. I bet a significant fraction of Mottizans are still people who originally found it because even a filter as simple as "read Scott-Alexander-adjacent things" can still be competitive with the alternatives.
roystgnr
10d ago
I want to read more science fiction, I haven't been able to get into the genre in a while.
If you liked Stranger, it arguably isn't Heinlein's best work. The Moon Is A Harsh Mistress is more widely highly regarded, and Time Enough For Love is more polarizing but more highly regarded by many.
Basically, I'm in the mood for lighter fare.
If you're not averse to books for tweens and teens as being way too light, Heinlein's "juveniles" (my favorite was Citizen of the Galaxy) and juvenile-accessible novels (especially Starship Troopers, Double Star) were pretty good for what they are.
roystgnr
11d ago
This comment undercuts the moral argument for Georgist taxes pretty severely. (I've long been suspicious of the practical argument in general, although the practical argument of "we ought to incentivize the medieval sheep farmer to get the hell out of the middle of London" still makes a huge amount of sense in your hypothetical.)
A tax that can be framed as "We're just taxing the value that the rest of society has provided to you" feels like a huge moral advance over the typical lesser-of-two-evils "We can't make civilization work without lots of money so we're raising the amount of yours we'll take; pray we don't raise it further". And this moral justification for land-value tax makes some sense, for land uses where most of your revenues (and/or at least your use-value for a homestead residence) really come from the value of proximity to your neighbors. But what if you just wanted to farm sheep, and the main thing your neighbors have done to aid that is dump a bunch of air pollution into their lungs and their wool? Asking you to pay ever-increasing taxes for that service seems almost cruel.
roystgnr
11d ago
Per capita, it looks like the post-Covid immigration increase in Ireland was roughly the same as the increase in the UK; the only obvious difference in the total numbers is that for the UK this was unprecedented whereas Ireland had an equally large immigration surge 15 years or so ago. The composition is fairly different, though. E.g., since we're talking about the grooming gangs scandals again, Ireland has something like 30% as many Pakistan-born residents per-capita as the UK.
roystgnr
11d ago
That's weird. Usually LLMs have exactly the opposite problem. I would find them infinitely more useful if the worst case output was "I've never heard of that" rather than confident-but-wrong hallucinations. I guess "that doesn't exist" is still in confident-but-wrong territory, but it's not the usual "yes, and" improv ad-libbing I see.
roystgnr
11d ago
The nice thing about building AI via training on human text is that it increases the odds that the resulting superintelligence will care too much about humanity to just let us die.
The scary thing about building AI via training on human text is that it increases the odds that the resulting superintelligence will care too much about humanity to just let us die.
roystgnr
14d ago
Applying a significant electrical charge to leading and trailing edges of a wing can get you silent thrust, but it's not antigravity, it's just a form of ion thruster that uses the atmosphere itself as reaction mass:
https://hackaday.com/2016/07/13/expanding-horizons-with-the-ion-propelled-lifter/
And it's hard to make useful, because the catch is that you'd need about a million times more thust if you even wanted to lift your own power supply rather than be tethered to it. I suppose maybe you could combine the idea with beamed power, but you'd still need line-of-sight to a powerful ground station, and regardless your craft wouldn't resemble an airplane so much as a spiderweb.
roystgnr
21d ago
I never watched the sequels, but at least in the first movie he does call the police (albeit way later than he should), and his "doing things yourself" adventure ends with his enemies capturing him and gleefully discussing his torture, until he's rescued by an adult. The script is all about "heroic adventures doing things yourself", but they avoid blatantly teaching it as a bad lesson.
roystgnr
22d ago
No; Arianespace is clearly a high tech aerospace company. But the phrase you responded to was "major tech companies", and if you'll forgive my moving the goal posts back to that, retaining ~1% of a market vs a competitor you got decades of head start against is not "major".
SpaceX accomplishments are of such magnitude that Arianespace once called them "a dream" (derogatory). It's cool that they can still reach orbit, but they're just not in the same league ... and what's most damning is they have no plans to fix that! They're not like Blue Origin, with big plans that are just running late; their remaining market is a political sinecure, so they're content with it. They're not a company you want to name to contest the differences between US and EU innovation, they're a company you want to name to demonstrate it!
roystgnr
23d ago
Ariane? The space company with 3 launches in the past two years? That's a smaller manifest than SpaceX last week.
roystgnr
24d ago
I think math just inherently requires more structure
Khan Academy has pretty much solved this problem for pre-college math.
and pushing
But here ... yeah, it really depends on the kid. Letting our kids work independently (along with a charter school that is very flexible), my son got 5 or 6 years ahead in math because he loves math, his older sister got a couple years ahead because she loves the idea of getting into a good college, and his younger sister just does what she's asked to because she loves her mommy, which is going to put our "don't be pushy parents" philosophy to the test in the coming years.
roystgnr
24d ago
Not worthless, and you could come up with a coherent subset of teachings; the result just tautologically wouldn't be Christian. "Christ" wasn't a surname; it's Greek for "anointed one", like Hebrew "Messiah".
roystgnr
27d ago
How is that not a threat? It's just "If you do that when I'm able to kill you, I will" but in subjunctive rather than future tense. Either way, after the criminal's release the victim has to choose between avoiding the threatened speech or getting killed.
roystgnr
30d ago
That pushes the mystery back one step, anyway. Why did they do that, and other countries didn't?
roystgnr
1mo ago
Or compare the Ming Treasure Voyages cancellation with the European Age of Exploration. China was on top of the world, but their institutional infighting manifested as stasis while Europe's often-more-literal infighting manifested as a mad scramble for power, and the difference in incentives set China back centuries.
Compare East Germany with West Germany, or South Korea with North Korea. The economic effects of better vs worse governance on nearly-the-same-genes can literally be big enough to see from space.
I think a more interesting wrench in the gears is the question of better vs worse culture, though. South Korea has a lot more lights than North Korea in all the satellite photos, but at 0.72 and still falling TFR they might as well start turning lights off now before the last person "leaves". Their genes haven't significantly changed, and their government changes over the past 60 years (since the TFR started falling from 6) seem unrelated, but the cultural changes have been massive and baffling. Nerds started getting a mathematical handle on voting system foibles and game theory back around the time of Condorcet (though we've now got much better alternatives to FPTP than IRV-misnamed-as-Ranked-Voting, so the lesser-nerds' focus on the latter at this point in history is weird...), and likewise for economics and at least the most obvious Communism-level economic mistakes. But does anybody have any sort of mathematical analysis of WTF happened in South Korean culture, to cause the gender war to get so bad and the fertility rate to plummet eight-fold in 2 or 3 generations? It's like the stereotype of the pushed-into-overachievement kid burning out and becoming suicidal, but on a 50-million-person scale!
roystgnr
1mo ago
75-85 is higher than average for a healthy adult, and I'd generally recommend cardio to try to improve it, but it's "worse than the median", not "infarction at any moment".
What was up with the tachycardia surgery, though? If you've had doctors looking at the problem before and recommending surgical (ablation?) treatment then you should probably ignore general recommendations and ask your GP or cardiologist about your specific situation. The answer might be "yeah, you're physically normal now, the general advice applies" or "yeah, exercise, but in your case it should be lower intensity for longer times", but there's a tiny chance of something like "oh, shit, we need to take another scan" that you'll never learn from a rando.
roystgnr
1mo ago
Math is where the inverse of "the" logarithm function is eˣ, computer science is where it's 2ˣ, engineering and science are where it's 10ˣ.
More seriously, your definition of engineering is way better than theirs. Half of engineering is figuring out where it is and isn't safe to not bound your model to the laws of physics and chemistry too tightly. E.g. atoms are a pretty big deal, but if your elasticity model is atomistic and you're building something that's not nanometer-scale then you're doing it wrong.
roystgnr
1mo ago
I see the 1st stage vehicle design as optimized for heavy surface to low orbit launches.
Nah. The 1st stage vehicle design is optimized for reusability. The staging velocity is much lower than you'd want to minimize fuel use, because that way it can fly back to the launch site easily enough, and fuel is cheap but time and operations complexity is expensive.
The second stage is confusing, mixing atmospheric engines and heat shields with vac engines for fairly inefficient interplanetary burns.
The heat shields are what it needs for reentry, and the atmospheric engines are what it needs for controlled landing, and those are what it needs for reusability. You're using the same pointless definition that most rocket design programs have: that "efficient" means "payload divided by fuel mass". But fuel is cheap, and the most meaningful definition of "efficient" is actually "payload divided by cost". If each SLS costs $4B to launch, it could have the highest fuel-efficiency quotient of any rocket ever in history before or since and yet its true efficiency would still be too low to ever be sustainable.
Why is this better than launching a lightweight interplanetary-dedicated ship plus a smaller lander?
A smaller lander means you need more landers. Approximately one hundred times more landers, if you compare the heaviest thing landed on Mars so far (Perserverence) with Starship payload capacity. Starship is gross overkill for putting a flag and a few footprints on Mars and then never going back, but it's about what you'd want as the minimal scale product for a large base or a small city.
STO heavy lifter
Did you mean TSTO? Part of the genius of the Starship design is the realization that, if you have a reusable two-stage-to-orbit design, you've basically also got a three-stage-to-Mars design, just by refueling the second stage and then using it as the third stage too. So instead of launching your big Mars transfer vehicle via a bigger second stage and a bigger-squared first stage, you can get rid of the "squared" level of scaling and just do more launches.
NASA designs avoided going anywhere near this in part because talking about orbital refueling used to be forbidden there. I'd love to place all the blame on a few folks like the former Senator of Alabama, but really once Congress started treating space as a jobs program, the idea of cutting costs was doomed already, and infighting over which costs were the most uncuttable was just icing on the cake.
Is the whole mars thing just hype for what's really a STO heavy lifter?
This, on the other hand, I can't entirely rule out. It would be incredibly shitty hype for investors, because "we're just going to plow our profits into a program that won't pay off in your lifetime" is an awful spiel for getting your hands on someone's retirement fund, but for employees it's been pretty effective hype, a big part of how they've been getting very talented idealistic young people to work very long hours with otherwise barely-competitive salaries.
I don't see how the math works out for a bait-and-switch at this point, though. Starship development wouldn't make sense as a purely greedy investment unless they really expect it to undercut Falcon 9 internal costs, which means a flight rate on the order of what they're pulling off today with Falcon 9, which means so much tonnage to orbit that they'll be able to continue the Mars side of the program as a loss leader. Even if Musk is secretly planning to pull an "aw, shucks, we're going to want to cash out most of those Starlink profits in our lifetimes after all", or he somehow gets pushed out by someone else who wants to change plans, they'd still want to earmark a dozen launches for Mars every so often just to keep attracting talent.
I admit to writing very loosely last night (rushing and not editing as I boarded a plane), but despite wincing at my "never" hyperbole I still could nearly bite this bullet:
Append "above a determined rate" and you get the typical FAA/NASA solution: achieve "no" failure by conservatively predicting failure risk and then not flying until your design has pushed that risk under that rate. This doesn't work well (see: Shuttle), and if overapplied this philosophy would be the death of SpaceX R&D ("If things are not failing, you are not innovating enough." - Musk), which is vastly more time- and cost-efficient and more successful than that of it's more hardware-efficient competitors, but selectively applying this philosophy to the cases where it's someone else taking the risks' downsides may not be crazy.
A more outside-the-box alternative would be having better failsafes than "activate hypersonic shotgun mode" for failure. This particular failure wasn't a "now you see the spacecraft, now you don't" thing like Challenger, it was a video-visible bay fire, followed much later by a grossly telemetry-visible propellant leak, slowly followed by gradual failures of one engine after another, all on a stage for which the ability to reenter in one piece and target a landing spot without propellant use is it's whole raison d'etre. Even without trying to make use of that, in this case simply cutting off propellant to delay the explosion could have pushed the debris field further east over empty ocean.
Maybe those are crazy solutions. But we live in a world run by voters full of crazy demands. The attitude of "what do you wanna do, basically quit spaceflight?", in a world where we haven't been back to the moon for half a century, shouldn't be considered as a final argument without always remembering that one man’s modus tollens is another man’s modus ponens. I'm a huge fan of spaceflight, and I'm a huge fan of SpaceX in part because so far they're the only ones in history to take spaceflight at scale seriously. But they've done so at the discretion of regulators who insist that they can be stopped in their tracks if they don't e.g. first get good psych test results from kidnapping a seal and playing it Spotify's Greatest Sonic Boom Hits. This is not a world in which "don't let chunks of your test flight fall on people" is an obviously evadable requirement.
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