Los Alamos is capturing images of explosions at 7 millionths of a second(lanl.gov)
lanl.gov
Los Alamos is capturing images of explosions at 7 millionths of a second
https://www.lanl.gov/media/publications/1663/dynamics-of-dynamic-imaging
105 comments
While we're nit-picking the title, what does the "real-time" part mean? How would it be different if it wasn't real-time?
Dictionary.com defines "real-time" like as, "the actual time during which a process or event occurs", eg "along with much of the country, he watched events unfolding in real time on TV". Or in the domain of Computing, "relating to a system in which input data is processed within milliseconds so that it is available virtually immediately as feedback to the process from which it is coming, e.g. a missile guidance system might have "real-time signal processing".
Neither definition work here. It seems like they took a sequence of pictures very quickly, and then, some time later, played them back at an enormously slowed-down rate.
Dictionary.com defines "real-time" like as, "the actual time during which a process or event occurs", eg "along with much of the country, he watched events unfolding in real time on TV". Or in the domain of Computing, "relating to a system in which input data is processed within milliseconds so that it is available virtually immediately as feedback to the process from which it is coming, e.g. a missile guidance system might have "real-time signal processing".
Neither definition work here. It seems like they took a sequence of pictures very quickly, and then, some time later, played them back at an enormously slowed-down rate.
The opposite of "real-time" in this context would be "sampling". It means that the capture represents the high-resolution time history of one particular event (one explosion) instead of fast and successively offset captures from as many events.
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The first line of the articles says "seven-millionths of a second", which would be 1/7μs or 0,14μs. They also mention that the camera shot 16 frames in that period, so that would be once every 0,00875μs or once every 8,75ns
Youtubers are a couple of magnitudes away from that, AFAIK
Youtubers are a couple of magnitudes away from that, AFAIK
I would say you described "one seven millionth" of a second (1/7,000,000 s)
"Seven millionths" would be 7/1,000,000 s (7μs). They take 20 to 40 images in that period using 7 cameras, so any given camera might be as low as 1.4μs per frame.
"Seven millionths" would be 7/1,000,000 s (7μs). They take 20 to 40 images in that period using 7 cameras, so any given camera might be as low as 1.4μs per frame.
Saying ~140k photos per second would have been a more understanding stat if only the article framed it that way.
Yes, but they said seven-millionths of a second, not seven millionths of a second. Technically they're right that that's what it means, but I'd expect an editor to recommend against that phrasing in favor of the one you used to avoid confusion.
Well, it's true that the article says "seven-millionths".
I would guess it's a lot more likely that this is an editing failure, introducing a hyphen where no hyphen should be, than that they meant to divide a second into seven million equal parts.
For one thing, as SECProto alludes to, English would normally require you to say "less than a seven-millionth of a second" if that was what you meant. There's no such thing as saying "less than weeks". You have to specify less than how many weeks.
I would guess it's a lot more likely that this is an editing failure, introducing a hyphen where no hyphen should be, than that they meant to divide a second into seven million equal parts.
For one thing, as SECProto alludes to, English would normally require you to say "less than a seven-millionth of a second" if that was what you meant. There's no such thing as saying "less than weeks". You have to specify less than how many weeks.
less than (seven) (millionths of a second)
less than (seven millionths of a second)
I agree based on the whole sentence in the article that that was probably an editing error.
The slow mo guys did a video [1] at 10 trillion FPS. They also recently did another video [2] at 5,000,000 FPS. Their other videos vary between 50,000 FPS and 850,000 FPS.
Edit: They mention in [2] that the Phantom camera they have can go to a 95ns exposure up to 1,750,000 FPS.
[1] https://www.youtube.com/watch?v=7Ys_yKGNFRQ&pp=ygUMc2xvdyBtb...
[2] https://www.youtube.com/watch?v=BTkZ36g4GOs
Edit: They mention in [2] that the Phantom camera they have can go to a 95ns exposure up to 1,750,000 FPS.
[1] https://www.youtube.com/watch?v=7Ys_yKGNFRQ&pp=ygUMc2xvdyBtb...
[2] https://www.youtube.com/watch?v=BTkZ36g4GOs
The 10 trillion FPS number comes from the fact that they’re taking advantage of a strobing effect in the light they’re filming, such that if the strobe is happening at (for example) 1000Hz, they can get a frame at time T, then a frame at time T + 1.00000000001ms, then T + 2.00000000002ms, and so on. Then you stitch it together and it looks like they’re a 10-trillionth of a second apart.
No camera is taking in 10 trillion frames of data per second.
No camera is taking in 10 trillion frames of data per second.
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"electron beam that can be broken down into customized pulses" also sounds superficially like strobing.
Not with X-rays they aren't.
I understood the article just fine, despite the spurious hyphen. The HN title could be improved immensely if it just said 7 microseconds.
I think this is incorrect reading of the numbers
I've never heard of `{number} {plural magnitude}` meaning `mag / number`. I've only ever seen it mean `number * mag`. As in 3-thousandths == 3 * 0.001 not 0.001 / 3.
7 * 0.001ms = 0.007ms or 7us or 7000ns.
I've never heard of `{number} {plural magnitude}` meaning `mag / number`. I've only ever seen it mean `number * mag`. As in 3-thousandths == 3 * 0.001 not 0.001 / 3.
7 * 0.001ms = 0.007ms or 7us or 7000ns.
I read it as months. Super confusing.
7 months/seconds - Its both a dimensionless quantity and a variable. Very impressive. Los Alamos is taking the USA's 'anything but metric units for measuring' to new levels.
Fascinating look into the dynamic imaging capabilities at Los Alamos National Lab—essentially, how the U.S. is able to analyze nuclear-level explosive events without actually conducting nuclear tests.
The Lab uses multiple systems to image these high-speed events:
• pRad uses proton radiography to get 20–40 frames of a detonation, with material-level resolution based on density.
• DARHT uses dual-axis x-ray imaging to create 3D snapshots from two angles, ideal for testing whether the computational models built from pRad hold up.
• Scorpius (in development) will take this a step further by using subcritical plutonium in a new accelerator at NNSS, capturing multiple high-resolution frames just nanoseconds apart.
The fact that they can tailor experiments based on frame-by-frame behavior of individual materials under explosive stress feels like the real-world version of “bullet time” physics modeling. The margins of error come down to billionths of a second.
The Lab uses multiple systems to image these high-speed events:
• pRad uses proton radiography to get 20–40 frames of a detonation, with material-level resolution based on density.
• DARHT uses dual-axis x-ray imaging to create 3D snapshots from two angles, ideal for testing whether the computational models built from pRad hold up.
• Scorpius (in development) will take this a step further by using subcritical plutonium in a new accelerator at NNSS, capturing multiple high-resolution frames just nanoseconds apart.
The fact that they can tailor experiments based on frame-by-frame behavior of individual materials under explosive stress feels like the real-world version of “bullet time” physics modeling. The margins of error come down to billionths of a second.
Thank you for contextualizing this. We are truly living in a wild part of the space time continuum.
Every time I read about one of the national labs doing this research, I wonder how much longer we will head about these. I feel fairly positive that DOGE's layoffs and budget cuts mean this output will fade away in time.
I worry about this, but these capabilities are hard to replace. This kind of research hasn’t historically been something you can outsource to private companies. Or—at least—it hasn’t been until now. Even if this administration wants to open that door, the infrastructure investment required for the accelerators alone is staggering: easily in the multiple billions.
Maybe I'm misreading your comment, but you seem like you're talking about privatizing this research whereas the other commenter seems to be talking about public cuts leading to a reduction of research. Just because something gets cut doesn't mean it gets outsourced elsewhere.
I guess my point is that it's hard to simply cut research that's essential for certifying that the stockpile is safe and works. I'll avoid making any predictions, because who the hell knows what's going to happen, but I think dynamic imaging work may prove a tough target for DOGE.
Yes. It is hard to this honestly and correctly. That would mean that normal people wouldn't make these cuts.
It also has very little predictive power for the loon with the checkbook right now. He might just as likely notice that people care a lot about that issue and hold it for ransom.
It also has very little predictive power for the loon with the checkbook right now. He might just as likely notice that people care a lot about that issue and hold it for ransom.
I think the overall aim of DOGE is simply to move research into privately controlled entities, especially those that can’t be cut. Its simply a continuation of transferring the national asset base (tax/usd) from democratic control, into private control.
It doesn’t need to be profit making in the normal sense (see SpaceX) it just needs to be the only game in town when the US Gov spends on national security
It doesn’t need to be profit making in the normal sense (see SpaceX) it just needs to be the only game in town when the US Gov spends on national security
Why not just rubber stamp the certification and save all that money?
It’s for bombs, it’s untouchable.
It might end up financing a gold-plated airplane for a library.
For context for casual readers:
https://www.nytimes.com/2025/07/27/us/politics/air-force-one...
Which may explain why no one wants to discuss a mysterious, $934 million transfer of funds from one of the Pentagon’s most over-budget, out-of-control projects — the modernization of America’s aging, ground-based nuclear missiles.
https://www.nytimes.com/2025/07/27/us/politics/air-force-one...
I don't think defense budget is facing cuts. They are getting even more money.
The national labs are absolutely getting budget cuts.
For sure. But depending on what Congress does, think defense budgets could grow, which would mean more money for defense-positioned Labs like Los Alamos.
Nuclear research is done under the Department of Energy, not DoD. Los Alamos is a DoE lab, and the DoE received major cuts in the recent budget bill, though that shifts energy efficiency research into weapons research and net increases lab funding.
Los Alamos is an NNSA lab; NNSA is a semi-autonomous component of DOE and its weapons activities budget is distinct from the general DOE budget. NNSA’s nonproliferation budget has been cut but they’re still very well funded on the weapons side even if they’ve lost quite a lot of people in the last few months.
The national labs are organized under the Office of Science (17 labs), NNSA (LANL, LLNL, Sandia), the Office of Nuclear Energy (INL), the Office of Environmental Management (Savannah River), Office of Fossil Energy (NETL), and Office of Energy Efficiency and Renewable Energy (NREL). Some offices are doing better than others re: funding in the current environment!
The national labs are organized under the Office of Science (17 labs), NNSA (LANL, LLNL, Sandia), the Office of Nuclear Energy (INL), the Office of Environmental Management (Savannah River), Office of Fossil Energy (NETL), and Office of Energy Efficiency and Renewable Energy (NREL). Some offices are doing better than others re: funding in the current environment!
I have heard that their internal review processes for papers have started telling people to not say stuff like "XYZ may be useful for climate research" or "this is an alternative energy source that's environmentally friendly." Like they are literally discouraged from talking about climate stuff at all lol.
Wouldn't surprise me. Getting rid of the other research programs won't be great for the labs though. The weapons research has a bunch of weird incentives because of the geopolitical context it exists in. The goal usually isn't to operationalize research, it's to have credible evidence of a functioning nuclear program, maintain the arsenal, and act as a jobs program for nuclear physics. The other programs act as a way to operationalize things in socially acceptable ways. If you get rid of them, I suspect the labs aren't going to be better-off for it even with more funding.
That’s going to the MIC grift though.
Labs like this also have huge black budget spending that we don't get to see.
I'm guessing we'll see more hidden spending in future as the nukes and the engineers that made them get older. its worth asking if they even work (in some countries arsenals at least)
I'm guessing we'll see more hidden spending in future as the nukes and the engineers that made them get older. its worth asking if they even work (in some countries arsenals at least)
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gosub100(13)
Pardon for the old meme here, but... "Pics, or did not happened!"?
Yeah I kind of expected explosionpron not camera rig diagrams.
Discussion continues, with more on dynamic imaging and the labs, here: https://news.ycombinator.com/item?id=44876919
It's an apples-to-oranges comparison, but I'm reminded of the ~10^12 fps (1.7 ps exposures) demonstrated in work at MIT[0], which was for a completely different application.
[0] https://web.media.mit.edu/~raskar/trillionfps/
EDIT: Video with explanation. https://www.youtube.com/watch?v=EtsXgODHMWk
[0] https://web.media.mit.edu/~raskar/trillionfps/
EDIT: Video with explanation. https://www.youtube.com/watch?v=EtsXgODHMWk
Why are science communicators so consistently missing the mark?
Is it not obvious that if you're writing an article proclaiming to capture _explosions_ at 7mths of a second, people want to see some pictures of said explosions?
Clearly they're understanding that explosions are a hook to grab the reader's attention, but then they just don't include any of the resulting pictures?
C'mon y'all! We need to do better here!
Is it not obvious that if you're writing an article proclaiming to capture _explosions_ at 7mths of a second, people want to see some pictures of said explosions?
Clearly they're understanding that explosions are a hook to grab the reader's attention, but then they just don't include any of the resulting pictures?
C'mon y'all! We need to do better here!
For more on this, look at the DAHRT project. It occurred up the hill a bit from LANSCE, in DX instead, but did similar things
Pics or it didn’t happen.
I imagine this falls under the remit of "nuclear warhead research without actual warheads".
> When it’s ready, experiments at Scorpius will be similar to DARHT but with the added complexity of using subcritical amounts of plutonium instead of surrogate materials.
They basically explicitly say that without just coming out and saying it. This kind of hyper fast explosion analysis and photography is a big part of making implosion bombs work properly.
edit: actually they just say it, they don't have to be coy everyone knows the US and other countries study this and it doesn't violate the NTBT because it's sub critical.
> essential to the Lab’s stockpile stewardship mission because it helps scientists test and understand the fundamental characteristics of materials and explosive events to inform computational models and analyses without ever detonating an actual weapon.
They basically explicitly say that without just coming out and saying it. This kind of hyper fast explosion analysis and photography is a big part of making implosion bombs work properly.
edit: actually they just say it, they don't have to be coy everyone knows the US and other countries study this and it doesn't violate the NTBT because it's sub critical.
> essential to the Lab’s stockpile stewardship mission because it helps scientists test and understand the fundamental characteristics of materials and explosive events to inform computational models and analyses without ever detonating an actual weapon.
Wow, this is wild. billionths of a second?!
"Millionths", abbreviated "mths of a second" here for... reasons...
Known to the entire world, including American STEM people, as a microsecond.
Known to the entire world, including American STEM people, as a microsecond.
Anything to avoid using the proper units, you wouldn't want the Americans audience to be enlightened wouldn't you.
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I'm reminded of Grace Hopper's famous nanoseconds lecture: https://youtu.be/gYqF6-h9Cvg?t=78
1 ns * c = 1 ft, to put in perspective: 7 μs * c is 1.3 miles.
(Protip: just type "7 μs * c in miles" into Google)
(Protip: just type "7 μs * c in miles" into Google)
7 μs is also the time it takes light to travel about 1,400 Ariana Grandes.
In which direction? Presumably side to side?
Due to relativity the length of Ariana Grande will appear to change such that all observers agree on the same speed of light.
Oh, I haven't watched that before.
Not quite. The article says hundreds of nanoseconds, which would be in the 10 millionths range. Or if you take the title literally, 143ns per image. That's in line with the fastest CCDs, so not unimaginable.
Do the images match the simulations?
Soon to be defunded too I suppose.
Can we see some these pictures?
Are the images available?
Error 404.
edit: here is the important information in this article.
> Scorpius is a new accelerator project planned for the Nevada National Security Site (NNSS) that will use an electron beam that can be broken into customized pulses to deliver x-rays and capture multiple images only hundreds of nanoseconds apart.
So 0.1μs or 100ns temporal resolution 3D X-ray.