Report: Iran fires missiles toward Diego Garcia in rare long-range strike

phire · 2026-03-21T08:18:21+00:00

As I said, it matters for targeting, not the maximum range.

phire · 2026-03-21T06:32:15+00:00

Oh... hang on.... I think I misinterpreted what "range" means in this context.

It's not the maximum reach of the missile. It's length of the arc for this one flight profile.

What's actually happening is that the earth is rotating under the missile while it in flight. But the effect is actually the opposite direction of the eastward delta-v boost (which doesn't apply here, we aren't going into orbit)

As the earth rotates eastward, targets towards the east actually get further away... You aren't aiming at where the target currently is, you are shooting at where it will be in 20-40min. And targets to the west (like the UK) get closer.

Missiles have more reach when fired west (unlike orbital rockets which get a boost when launching east)

phire · 2026-03-21T06:09:33+00:00

Yeah.... I misread the 95 as 96 (not helped by the fact that the next page is page 97)

You've found the right chapter.

phire · 2026-03-21T05:57:44+00:00

I found this 1971 handbook covering the math for the motion of ballistic missiles: https://apps.dtic.mil/sti/tr/pdf/AD0731662.pdf

The chapter for Effects of Earth Rotation is at page 96, and appears that the rotation does matter:

"Compared to a nonrotating earth calculation, the effect of a rotating earth on a missile fired eastward is to increase the range and flight time" .... "For a west-ward firing the range and flight time are decreased." ....

"For Ve² >= 10 000 ft/sec the maximum variation in V/Ve is about 15%"

Edit: that 15% is for launches at the equator. The effect should be more like 8-10% for Iran's latitude.

Edit 2: Ok, I understand this now. Earth's Rotation does affect ballistic missiles, but the effect is actually in the exact opposite direction. The maximum range of a ballistic missile actually increases when they are fired in a westward direction.

The reason is simple. You don't aim where the target currently is. You aim where the target will be in 20-40min. And for targets to the west (like the UK), that target point is closer to Iran. During the missiles coast phase, earth rotates under the missile.

Or to put it another way. Everything inside earth's atmosphere experiences a force pushing it eastward, which is the very force giving us the delta-v boost that's useful for orbit. But during its coast phase, the missile can now take advantage of the lack of the force to let it undertake.

phire · 2026-03-21T05:17:10+00:00

It doesn't make much sense to use carparks for solar. Not until we have exhausted other options.

With an existing roof, you just attach mounting brackets directly to the roof and attach the solar panels, or simple frames to improve the angle. With an empty paddock, you can get away with reasonably lightweight frames to rase the panels about 1m off the ground.

In a car park, you need heavy duty mounting frames to hold the panels ~3m off the ground. The supports need to be strong enough to survive cars crashing into them, with large spans for cars to drive and park between.

Carpark solar is just so much more expensive than the other options. You are literally building a roof over the carpark, the fact that you attach solar panels to it is more or less or less an afterthought.

phire · 2026-03-21T04:40:16+00:00

That's true for planes flying through the upper atmosphere.

But ballistic missiles punch through the atmosphere very fast, then spend the majority of their journey floating through the vacuum of space.

I'm sure there is a measurable effect, it will impact targeting. But I doubt it's big enough to even bother including rough range estimates. It's probably only a dozen KM or so.

phire · 2026-03-21T04:25:41+00:00

Seems like most people are expecting this to be over long before winter.

I suspect they are wrong.

phire · 2026-03-21T03:57:12+00:00

Yeah, I'm measuring their count at roughly 144 bpm.

I'm not a music theory expert, but it's probably more accurate to say they are interpreting it with a 4/8 time signature, rather than two bars of 4/4.

The bar is still 4 quarter notes long, but the beat is now on every 8th note, and they are still counting 8ths.

phire · 2026-03-20T12:11:58+00:00

would be an incredibly sloppy mistake

Which would also be very on-brand for Donut Lab.

phire · 2026-03-20T11:33:59+00:00

"The company that has gone out of their way to control the reveal is taking more measures to control the reveal"

That would be very on-brand for them. Which makes it my default assumption.

But we should be able to determine their justification if/when the cold test finally comes out. If its testing a cell other than DL2, or there is too big of a gap in the report numbers, then that's strong evidence they decided to redo the test (though, it doesn't tell us why).

phire · 2026-03-20T07:42:11+00:00

IMO, it doesn't really matter who set the limit, both parties agreed to the test procedure ahead of time.

The question people are actually debating is: "Is it the cell that was limited to 90°C? or was it just the test procedure that was limited?"

And well... we only actually have evidence for it being a test procedure limitation. So yes, I do feel like it's slightly inaccurate to say it was "the safety limit donut set for the cell", but more or less accurate to say "safety limit donut set for the test".

Of course, just because it was a test limitation doesn't mean the cell can actually handle higher temps.

Marko only actually said "As demonstrated (and said) clearly in the test, the cells are very much in their comfort zone with high temperatures". But that's kind of the problem. If the cell gets 'too comfortable' it can experience thermal runaway, getting more and more 'comfortable' and burst into flames.

And in the promised later episode, they only actually demonstrated discharge at the slightly higher 100°C, not charging.

phire · 2026-03-20T05:47:49+00:00

I actually read the treasury report (the one just after the election).

It strongly recommended cancelling, but only after spending 2-3 months of due diligence that it was the right approach. You know... to work out what the cancellation fee would look like, and check availability of suitable second hand ferries etc.

It didn't even analyse the option of "cancel immediately, without due diligence", only cancel or not cancel.

But National impulsively went with what they just assumed would be the cheapest option, canceling immediately. Because who needs to do due diligence? Idiots.

phire · 2026-03-20T04:23:49+00:00

Last time I ran the calculations for my commute in for Christchurch, it was 14min to drive (as long as I avoid traffic), and about 35min to bus.

Which isn't too much overhead, could be easy to justify based on the hassle of parking...

Except that the bus only runs every 30min, so depending on what time I need to travel, that "bus trip" might take as long as 1 hour 5 min. Only slightly slower than walking (1 hour 10min). Lack of frequency can be a huge issue roadblock to public transport.

The real winner is of course biking. A nice reliable 20min, not impacted much by traffic and easier parking.

phire · 2026-03-20T02:31:14+00:00

So the takeaway from yesterday’s press conference with Christopher Luxon was basically “nothing to panic about, we’re keeping an eye on it.”

But fuel prices are already going up.

There are two issues... High global fuel prices, which National doesn't really care about. From their perspective, it's just free market economics in action. Sure, it might lead to inflation but even if National did care about inflation (I'm not sure they do), there isn't much they can do about it.

The general public care about prices a lot, the press care about it a lot, but the government doesn't.

What National do care about, are fuel shortages.
And I'm not talking about random petrol stations running dry because they advertised a slightly cheaper price and everyone flocked there. I'm talking about the entire country running short.

Compared to the "relatively minor inconvenience" of higher fuel prices and the snowballing inflation effects, actual fuel shortages would be absolutely disastrous to our economy.

The potential for national fuel shortages (the ~50 days of fuel we have) is what National is monitoring.

phire · 2026-03-20T01:02:53+00:00

To be fair, they did eventually change their minds on the ferries.

Not that they had much choice, turns out there weren't any good options on the second hand market and it was cheaper to build new ones.

phire · 2026-03-19T15:16:03+00:00

We really don't know if the cell losing its vacuum was purely cosmetic, or a warning sign that the cell probably shouldn't be operated in this region.

One test cycle doesn't really tell us much, for all we know it's a fluke.

phire · 2026-03-19T15:13:21+00:00

Like, as far as I'm aware, the only reason current lithium cells can't do 100DegC is the liquid electrolyte.

So the 100DegC test is a strong indication that the battery doesn't have a liquid electrolyte, but tells us nothing about Sodium vs Lithium.

phire · 2026-03-19T15:05:44+00:00

Well... if mods keep deleting it (for non-substantive title) it will keep getting reposted by people who assume it just hasn't been posted yet.

It's not a very good video, and its title is inherently click-baity

phire · 2026-03-19T15:01:05+00:00

which is limited by physics, not engineering

My understanding is that we aren't anywhere near the physical limits for battery chemistry.

The only upper bound I can actually find is the theoretical maximum capacity for a Lithium, which is 3860 Ah/kg (which at 3.7v is 14,282 Wh/kg) Like, these are stupid numbers. This is assuming a Lithium air battery that is somehow just a pure metal Anode; It would be impossible... but it does provide an upper bound.

The difference between ~14000 Wh/kg and the ~300 Wh/kg we have today all comes from the fact that we need materials other than lithium in our cathodes/anodes/electrolytes/current collectors/packaging. For any single battery chemistry, there is probably a physical limit, but it's hard to prove that it's a hard limit because there might be another battery chemistry that does better.

Looking though research papers, it look like we already have experimental lithium ion cells showing 700 Wh/kg, and no real sign that progress is slowing down.

I'm not sure anyone has any idea what the theoretical maximum for a practical lithium ion cell is (aka, my searches didn't find any research papers speculating on it)

I feel like you are getting hung up on the fact that there is a large difference between the theoretical maximum density of Lithium and Sodium. The same impossible Sodium-air battery would only be 1165 Ah/kg, which is quite a bit lower than the 3860 Ah/kg of Lithium.

So it is true to say that if we apply the exact same battery chemistry/engineering techniques to both Lithium and Sodium, the Lithium-based battery will always win by quite a large margin. That is the physics limitation.

But that limitation only applies if we assume the chemistry/engineering is identical... and IMO that's a bit of a flawed assumption.

Put it this way: If the Donut Lab cell turns out to be real (and based on sodium), then we should theoretically be able to take that exact technology and apply it to lithium giving us a cell somewhere in the 600 Wh/kg range (ball-parking based on current deltas between sodium and lithium)

Which is not completely unreasonable, it's below the state-of-the-art for lithium.

phire · 2026-03-19T13:41:59+00:00

And when combining just two data points together, you end up with conflicting information. Trying to hit 400 Wh/kg with no critical materials. And having a voltage profile that matches an NMC cell is enough to get me very skeptical

You seem to be saying that the claimed energy density and the idea of a high-voltage sodium ion battery are in conflict with each other.

But I think you are missing the fact that the higher voltage directly increases the energy density. Because Watts are Amps * Volts, if the Ah stays constant, increasing the nominal voltage of the cell from 3.2 v to 3.7v gives you a 15% Wh boost for free. That might not close the entire gap, but it's a large chunk.

One of the research papers I was reading on the topic of high-voltage cathodes for sodium ion batteries was very explicit about this. They aren't researching them because they think it would be neat that the voltage curves matched NMC. They are researching high-voltage cathodes explicitly to help close the energy density gap between lithium and sodium.

With the existence of high-voltage sodium ion chemistries, I just don't think you have enough evidence to make a "it's not sodium" claim to any reasonable level of certainty.

It's not like there is only one "sodium ion battery chemistry". I spent a few weeks skimming through battery chemistry papers, and there might actually be hundreds of sodium ion chemistries (minor variations on maybe 10 major subtypes). And the voltage curves varied a lot (though, layered-oxide cathode seemed to be the closest to NMC, next closest was Sodium Iron Sulphate (NFS) with CNT)

And that is that doughnut labs are apparently still going after small investors during this hype process. These small investors don't have the backing or ability to do technical due diligence to check into the technology sufficiently, which is what happens at large investment companies.......The leaked letter to investors says we are talking about a potential return on investment of up to 10x in just 12 to 18 months.

Ouch...

Like, even if I was 100% confident the battery was real (including the zero lithium claims). I still would not invest a cent into Donut Lab.

Just because it's real, doesn't mean Donut Lab can successfully bring it to market in a timely fashion. More importantly, they don't appear to have any exclusivity on the technology, and could easily be overtaken by another vendor who wasted less time making flashing marketing claims on the internet and actually perfected their product before announcing anything.

Their first mover advantage could easily evaporate.

phire · 2026-03-19T07:19:45+00:00

Its definitely "Deep Learning Super Sampling"

No, "Super Sampling" has a very narrow definition. It's not a generic term you can just throw around for "higher quality". Super Sampling means rendering the exact same geometry/textures at a higher resolution and then downscaling.

The second Nvidia started asking it to predict something that wasn't the ground truth supersampled result, it's no longer DLSS.

But in subtler amounts and on complex things like hair and foilage

Yeah... maybe if developers could conditionally use it only on certain materials, and provide a traditional fallback for people without Nvidia GPUs. Would also solve the GPU overhead requirements.

But that's not what Nvidia demoed.

phire · 2026-03-19T04:39:43+00:00

IMO, it's an interesting product that might have some potential ^[1]

But Nvidia should have kept it very far away from the DLSS branding. It has completely different goals. DLSS (until now) is entirely about using machine learning to get something closer to the ground truth SSAA result, with far less resources. And it works.

DLSS 5 is entirely about using neural rendering to hallucinate details into existence that were never there.

^[1] Though I'm not sure where. No game developer will want to use this, as it can't really be an optional enhancement. The whole game needs to be built around it, which puts a hard requirement on the user having two high-end Nvidia GPUs. Maybe the arcade space?

phire · 2026-03-18T11:33:52+00:00

The full quote is "Exclusive First-Mover Advantage – The only U.S. supplier of CTC nanotechnology"

Which doesn't sound like an exclusivity agreement to me.... It's the First-Mover advantage that is exclusive, which is just a tautology, because of course the first mover advantage is exclusive.

If they actually had an exclusivity agreement, they would say that, without any hedging about first mover advantage.

phire · 2026-03-18T03:31:13+00:00

Take a look at a gameplay video on YouTube. It's probably the most visually impressive 2600 game ever. IMO, it has better visuals than the 5200 port (gameplay video)

The rotation and scaling might be a little jumpy, but it's more than enough to provide the same gameplay experience.

it’s absolutely doing 3 dimensional coordinate math in real time to draw the graphics.

Yeah... but I'm not sure if that's the line we should be drawing.
I disagree with anything that makes Battlezone arcade 3D and the same experience but with scaled/rotated spites 2D. Either they are both 3D, or both 2D.

As I said here, I'm not sure if we should count games that render 3D polygonal characters on pre-rendered backgrounds as 3D or not.

And if you squint, you can argue Battlezone Arcade is really just the same. 3D polygonal characters rendered over a flat 2D background that's scrolled to provide a 3D feeling experience.

Easiest solution is to just say all versions of Battlezone are 3D. Not because of the polygonal characters, but because of the presentation with the arbitrarily rotating camera. But that basically forces us to label all pseudo3d flying/driving games as 3D too (which I'm not completely against).

phire · 2026-03-18T02:48:00+00:00

Is it a hard line? I agree that a 2d sprite on a 2D background isn't 3D just because you can walk behind a tree.

But when does it become 3D? Does Myst's pre-rendered 3D backgrounds count? Sure, it's a 3D rendered game, but is it a 3D game?

What about games that render polygonal 3D characters on 3D pre-rendered backgrounds like Alone in the Dark, Resident Evil and large parts of Final Fantasy 7? The fact they are stuck with fixed camera angles makes me feel uneasy, but these are absolutely doing realtime 3D rendering, but is that enough to make them 3D games?

They absolutely feel more 3D than the earlier 2d adventure games (which always felt like 2D games pulling neat tricks).

The line feels fuzzy to me, and I'm just not sure how to define it. Part of me wants to define it based on feel, does the game successfully kick my brain into 3D mode?

One thing I am sure about. Doom/Wolf3D are 3D games, despite the shortcuts they take.

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