Of course they didn’t. The delta-v needed to land the rockets is better expended in pushing the craft further. Reusable rockets isn’t always the best choice.
Is 12 enough of a sample size to make a statistical judgement? What if there were 20 more which didn’t have a loss of life? Is it then 1/30? What if there were 20 more?
The risk factor is calculated _per mission_ from what I understand. You can have three accidents in a row and nothing for decades but the risk itself can still be 1 in 30.
Your point is fair and and important distinction. I think when estimating a risk factor though, this empirical data, while a low sample size, is a valuable statistic because it's empirical, and not that small of a sample size. Maybe going forward, we have 3 risk levels:
- Historical. Low N as you say. (Even though each mission and spacecraft is different and they're spread out over time, there's value in this)
- Bureaucrat number; absurdly low, but looks good to politicians etc
- Engineering estimate
Yes, actually. This is similar to having a 100 year flood five years in a row. It doesn’t mean that the flood occurs only once in 100 years. _On average_ it’s 1/100 probability of occurring in any given year.
But then, Apollo 1 was after all the first mission on the Saturn V. I think we should assess even its pre-launch risk much higher than the rest of them. Similarly Artemis II has a much higher risk than the subsequent ones will have.
But we’re talking about the risk of a defined set of events that have concluded, not a prediction of the future.
Of course Apollo would have likely had a better average if it had continued, but the risk of the Apollo program, as executed, included things like the first flight of the Saturn V.
If the final empirical mortality result of the Artemis program is 1/30 or less, it will be better than Apollo in that statistic.
A comparison of acceptable mortality is where this discussion began. If Apollo was acceptable at 1/12 (We did it, it was apparently acceptable as the program was not cancelled due to mortality rate) then an acceptable mortality of 1/30 is stronger than Apollo, not weaker.
If I toss a coin four times and it comes up heads three and tails once, it doesn’t mean that there’s a 75% chance that this coin lands heads up. Be careful about conflating risk factor and mortality rate.
But you doing better is independent of the risk involved. The chances of you getting 3/4 heads or better is around 31%, so theres ~69% chance you’ll do worse next time round. Doesn’t change the fact that each coin toss is still 50/50.
The original discussion was about acceptable mortality rate. Artemis's target is 1 in 30, which is better than the empirically observed mortality rate of the actual Apollo missions. The mortality rate is a target. And if that target is an improvement over the actual outcome of the Apollo missions, I think it's difficult to say that the target is weaker than Apollo's, which was the claim up the thread that I was responding to.
The public doesn't care if Apollo had a theoretical risk rate lower or higher than 1/12, what they saw was that 1/12 missions resulted in the death of the crew. The NASA administrator explaining that their estimated risk was only 1/1000 doesn't change the real-world perception or outcome.
> Doesn’t change the fact that each coin toss is still 50/50.
That assumes a fair coin. The fact is you don't know what the odds were of getting heads or tails for that particular coin, all you know is that you got 3/4 heads. And in this analogy, a few hundred coins have every been made, in maybe a dozen styles, none of which have been fair, so you have no good reason to believe that this particular coin should have 50/50 odds of landing heads up.
How are you/they instructing those agents? If you are writing detailed spec.md and reviewing those results, you are _still_ programming. Just in pseudocode effectively. I’ve seen enough session transcripts and detailed prompts that would have been easier to just write the code instead!
Remember that the defender has home team advantage. That’s precisely what you see happening both in Iran and Ukraine. That advantage exists with Taiwan. There’s a reason that China hasn’t made a move in all these years, and the US is only one part of that equation.
Homefield advantage is relative, between Ukraine - Iran - Gaza, Taiwan is closer to Gaza, which is to say not much after mitigating outside spoilers. Maybe less than Gaza vs force disparity involved. US is/was one part of equation, but big part of equation.
Discovering? It was announced a thousand times, maybe you dismissed because none of them were easily achievable?
Opening the Strait, renouncing nuclear program, renouncing ballistic program, regime change. Even Israel will be forced to retreat from Lebanon.
Iran won by choking the Strait and telling USA and Israel they could endure far longer than their aggressors could endure a few missiles and domestic support drop.
A Pakistani-made taco was not in my radar for today.
Opening the Strait was not a goal of this action; the Strait was open before this war started. They are trying to sell as a win a return to the status quo ante.
I dismissed them because the president and the Pentagon could not seem to articulate the objectives of the war in a way that was cohesive with one another.
Yeah obviously opening the strait wasn’t an objective. I think what you’re suggesting is that the mentioned reason - denuclearization of Iran - is unlikely to be the real reason, which may have been something like distraction.
This war is happening today, to exchange a future nuclear war with Iran with a conventional war today.
The US and Israel can fight a conventional war with Iran. They cannot fight a nuclear one. In a nuclear war, Israel would be destroyed by nuclear missiles in the two days. The possibility of a nuclear Iran is an existential crisis for Israel, and Israel will do anything possible to prevent Iran from gaining nukes.
That is why we have this conventional war happening today, (with unclear goals), to prevent a nuclear one in the future.
This war was unavoidable btw, it was going to happen sometime this year or next.
> This war was unavoidable btw, it was going to happen sometime this year or next.
Iran was, as per the latest reports I've read, complying with terms and not enriching uranium to weapons-grade or close to weapons-grade. Are there credible reports suggesting otherwise?
Those reports are old. IAEA inspectors have not been able to access any of Iran's nuclear facilities since the start of the 12 day war on June 13, 2025. Currently, nobody knows what Iran is doing with their nuclear material.
Although it might reflect actual considerations of Israel and, by extension, the US, that's ultimately a very unreasonable take. Iran might not have been trying to build nuclear weapons in the past, as they claimed. Maybe they did, maybe they didn't. In contrast, Iran will try to build nuclear weapons in the future with certainty. They'd be insane not to try now, after having been bombed for weeks in an illegal war of aggression against them and having been threatened with massive war crimes and genocide.
This sounds like goalpost moving. Like if you fail to acheive regime change, just say whateber the consequences of your failure were had been your objectives from the start. According to "some" who might "say"
You speak like you and I discussed this before, and you remember where the original goalposts were.
Many analysts suggested that the attack was a smoke-and-mirrors, and the actual goal has always been financial. Similar to the tariffs story. According to that opinion the outcome of the attempt is irrelevant. Regardless of whether the regime have changed or not, the goal is still achieved.
Come on man. The goal was regime change. They said its regime change. They were chasing the high of the maduro kidnapping. But then they ended up replacing Khamenei with Khamenei like they replaced the taliban with the taliban in afghanistan. Its fucking embarrassing
The key here is “could be”. But most four (or in my case, six) year olds can’t really grasp the abstract concepts of what JWST is or the data it’s sending back. For that matter most 40 year olds can’t.
A manned mission on the other hand is tangible in a way a probe isn’t. “See the big round thing in the night sky? There are four people going around it in a spacecraft”.
It isn’t a _complete_ argument in favour of manned missions- that has to account for the risk of the endeavour and reward of the science potential of having people there to react in ways robots can’t. But it’s hard to pretend that the inspiration pretty much everyone feels when they see manned missions is somehow achievable purely by robotic ones.
It _is_ RISC-V Vector extensions, so a very specific ISA in mind at the very least. There's another extension (not ratified I think) called Packed SIMD for RISC-V, but this isn't about that.
The name, yes, but going by name is a bad idea as the V in AVX also stands for Vector.
BTW, you'll be disappointed if you think of the P extension as something like SSE/AVX. The target for it is way lower power/perf, like a stripped-down MMX.
My point was about the underlying hardware implementation, specifically:
> "As shown in Figure 1-3, array processors scale performance spatially by replicating processing elements, while vector processors scale performance temporally by streaming data through pipelined functional units"
Applies to the hadware implementation, not the ISA, which is not made clear by the text.
You can implement AVX-512 with smaler data path then register width and "scale performance temporally by streaming data through pipelined functional units". Zen4 is a simple example of this, but there is nothing stopping you from implementing AVX-512 on top of heavily temporaly pipelined 64-bit wide execution units.
Similarly, you can implement RVV with a smaller data path than VLEN, but you can also implement it as a bog-standard SIMD processor.
The only thing that slightly complicates the comparison is LMUL, but it is fundamentally equivilant to unrolling.
The substantial difference between Vector and SIMD ISAs is imo only the existence of a vl-based predication mechanism.
If a SIMD ISA has a fixed register width or not, allowing you to write vector-length agnostic code, is an independent dimension of the ISA design. E
.g. the Cray-1 was without a doubt a Vector processor, but the vector registers on all compatible platforms had the exact same length. It did, however, have the mentioned vl-based predication mechanism.
You could take AVX10/128, AVX10/256 and AVX10/512, overlap their instruction encodings, and end up with a scalable SIMD ISA, for which you can write vector length agnostic code, but that doesn't make it a Vector ISA any more than it was before.
> The name, yes, but going by name is a bad idea as the V in AVX also stands for Vector.
Now I get your point after reading more of the linked page. Yes. It is very implementation specific.
One of the things about RVV (and in general any vector ISA) is that the data path can be different enough between different implementations such that specific rules of thumb for hand tuning most probably won’t carry over. As you say it is true of even sufficiently advanced SIMD architectures like AVX.
That was a bit overblown, due to my lack of knowlage about MMX. It has a lot more things than MMX.
But the core idea behind the P extension was to reuse the GPRs to do SIMD operations with little additional implementation cost.
As sibling said, stripped down in the sense it doesn’t have dedicated registers. In terms of supported functions it’s somewhere close to MMX.
I don’t personally like it because it still ends up with all the headache of building most of a vector subsystem (data path, functional units,…) while _only_ pretty much reducing one special vector file.
reply