▲ 241 points
back
166 comments
When I studied chemistry at university, only a handful of select students were introduced to the nuclear science lab in the basement. It had a lot of spicy isotopes, neutron sources, etc. Even as a chemistry student with free run of the place for years I had no idea it was in the building until the department head pulled a few of us aside.
The reason for the informal secrecy, as it was explained to me, is that every so often someone would find out there was plutonium etc in the basement and have a public freak out, including on occasion other (non-STEM) professors at the same university. These people would try to organize crusades to get it shut down because evil. Intentionally obscuring its existence greatly mitigated this drama. They appreciated us continuing the tradition of keeping it out of sight and out of mind from the general public.
The publicity around this Kodak case was an example of why no one talks about nuclear labs. The public cannot be trusted to engage in a discussion about anything “nuclear” in good faith. There are quite a few areas of science like this.
This is just like how universities hide their animal research facilities. It wasn't until the final year of my biology degree that I found out we had a basement floor under our life sciences building where this research is carried out.
I visited a few times as part of a research project I was involved in, and that experience was one of the factors that put me off pursuing a career in biomedical research.
If we can’t have a good faith discussion then maybe it is a good idea to hide nuclear and animal labs.
But with less oversight, that also invites abuse.
You can probably imagine abuse on your own in an anima lab, but I would also point out after Obama banned gain of function research in 2014 U.S. scientists moved their lab to China where it continued without the same oversight, and bad things happened.
To be fair an operational animal lab is an order of different ethical problem than safely storying radioactive material.
Could you describe the experience? I’ve always wondered what biomedical research was actually like.
I suggest we should strive for a more educated public to raise the percentage of people who can have informed discussions. We've seen what happens when education is watered down, so let's try raising the bar, and pushing more science in high schools.
These public freak outs is also why we don't have abundant nuclear energy.
The climate activists of the 60s-90s stopped us from building more reactors, one of the cleanest sources of energy ever known.
Climate activists backed and propagandized by the fossil fuel industry and the KGB.
And now that there are a number of barriers to creating new nuclear, the propaganda has flipped with fossil fuel companies supporting nuclear because they know it'll be decades before anything real can happen.
I have nothing against nuclear and if it can be built I'm for it. But at the moment, solar + battery is quick to deploy and about as cheap as you can get.
If the entire developed world had followed the same energy usage and nuclearization path as france, we’d be able to accommodate the entire developing world increasing carbon footprint up to the French level within the same overall carbon footprint we have today.
Same is surprisingly common when weeding books in university libraries. Care is often taken disposing of material, as it can trigger a lot of drama if discovered by the student body.
> The public cannot be trusted to engage in a discussion about anything “nuclear” in good faith.
I agree the fears and subsequent responses are generally not warranted but to call it “bad faith” (by saying not in good faith) is not fair either. Some people are afraid and don’t understand it. We’ve all seen seen the disasters and communities impacted with higher rates of cancer even decades later as a direct result of the Manhattan Project. This stuff can be dangerous so it’s not meritless even if the reactions are wrong and generally uninformed.
People not engaging in good faith are doing it very deliberately.
Same thing with animal testing. You don't get to know where the monkey labs are but the alternative is we test on poor people? learn to keep secrets, people.
RPI?
Yes, however I suppose it is fuel for conspiracy theories.
> In 1975, Kodak powered up the country’s first californium neutron flux multiplier (CFX) ... to provide Kodak R&D with an ample stream of neutrons for materials analysis.
> If an X-ray shows you the crack in a pipe, neutrons will show you the leak.
I see a lot of people claiming this sort of thing was “common” (JASON at the Royal Naval College London, MIT’s MITR-II, CROCUS at EPL) but there is a huge difference between these things. Kodak’s CFX was a small device the size of a refrigerator; it is a neutron source and not a reactor. CROCUS is a reactor, but also small (100W thermal) and JASON, while larger, is also low power (10 kW.) MITR-II on the other hand is nearly one thousand times larger at 6 MW thermal.
There are only three civilian reactors >1MW in the US: at MIT, UC Davis, and the University of Missouri. You could also count the RINSC MTR, which is owned and operated by the Rhode Island state Atomic Energy Commission but located on the University of Rhode Island campus and collaborates closely with the university. Similarly, there are only two >1MW in Western Europe (TU Delft and TU München.)
If this sort of thing interests you, I can recommend reading about the history of the TRIGA. Freeman Dyson and Edward Teller designed it as a reactor “safe even in the hands of a young graduate student” and the US government sent them around the world as part of Atoms for Peace.
UMass Lowell has a 1MW research reactor as well.
What a neat device. Unlike those extra spicy, dangerous sources that say "drop and run" on them, this thing only runs when you line up the CF-252 with the HEU plates. It has an off switch to stop the cascade. Perfect for lab use.
Cf-252 is no joke though. It has to be carefully handled. It constantly emits neutrons. And those need shielding, something with lots of light atoms like hydrogen - water, PET or other plastics etc.
At the Univ of Maryland College Park in the mid 1980s, a campus of 40k students, it was common knowledge the was a small research reactor in full time operation right on campus. I can't imagine it was the only school to have one.
My school for undergrad had, and still has, a "Nuclear Reactor Laboratory." I'm pretty sure everyone who cared understood what was going on there.
The university got in trouble in the mid nineties for having buried nuclear waste as well as medical waste (cadavers) on a remote part of campus, but apparently that's not enough to put a Nuclear Reactor Laboratory out of business. Or a large university's medical system, of course.
We also have one at NC State, still there AFAIK. I thought it made sense though given our nuclear engineering program.
I looked it up and apparently we've had 3 or 4 different reactors on campus over the years, first one in 1950: https://nrp.ne.ncsu.edu/about/history/
I'd wager that even most NC State students don't know that it's there though.
Kodak did a lot of government work over the years. When the news came out, no one panicked. Kodak was the biggest employer in the region and had a lot of local goodwill, we trusted them to take care of things.
Needless to say, that is no longer the case.
Kodak also accidentally detected nuclear fallout. https://www.orau.org/health-physics-museum/collection/nuclea...
The University of Toronto (among others in Canada) had SLOWPOKE reactors on campus.
It wasn't a secret like the article admits later on.
There are no secrets in a legal sense e.g. NDAs. However, there is a culture around private nuclear labs of giving no hint of their existence so that they can hide in plain sight.
The objective is to avoid attention, not to be secret per se, though the effect can be similar.
Seems like a distinction without a difference to me?
> And aside from a license renewal snafu in 1980, the device made no waves until its existence was shared with the local newspaper—it wasn’t a secret, just unpublicized.
> Indeed, it’s difficult to imagine trusting private corporations with the stuff atomic bombs are made of today.
Valar Atomics would like a word.
The Royal Naval College in Greenwich, London contained a secret, operational nuclear reactor from 1962 to 1996. Decommissioning it must have posed some interesting challenges, given it was inside a 300 year old building designed by Christopher Wren that is part of a UNESCO World Heritage Site.
I'm getting "Windows Subsystem for Linux" vibes from the project name. Shouldn't this be called a HEUFX with a Californium source?
I worked at the main Kodak tower in Rochester for a few years in the early 2000s. Mainly as a paid IT intern of sorts to earn some additional money in college.
I often had to go to the basement there to store equipment, get equipment, etc.
The stuff I'd see down there was WILD. TONS of old movie/film paraphernalia in the form of posters, plaques with celluloid celebrating various movie releases, and tons of unmarked old film canisters. There was also a TON of old tech down there.
I used to joke that I felt like I was in that Hanger 51 warehouse from the end of Indiana Jones and The Ark of the Covenant.
It's a shame things went down as they did for Kodak. I really enjoyed those years I worked there. They used to make killer tuna melt paninis in their cafeteria area near the top of the tower and in the summer months I'd keep my car parked at work and just walk across the street to see the Rochester Red Wings play (AAA minor league baseball team).
The University of Florida (Gainesville, FL), has a small nuclear reactor on campus. My mom always talked about it when I was young as she worked in the nuclear engineering department. I just checked and it's still active. Apparently it's been online since 1959.
https://news.ufl.edu/2025/10/uf-students-join-elite-ranks/
https://neup.inl.gov/infrastructure/university-research-reac...
OK, HN physicists: how did this work?
My first guess was that the beam of Cf252-emitted neutrons, when it hits the U235, triggers new neutrons moving in the same direction, rather than in random directions. This would ensure that any tertiary neutrons would join the crowd and help the amplification while not just heating the system up.
Or, maybe that's the point? It's a not-quite-critical collection of U235 that is pushed even closer to criticality by the Cf252, multiplying the Cf232's neutron flux by "up to 30 times". But, if the U235 neutrons trigger the same emissions as the Cf252 neutrons, then wouldn't that require a razor's edge of criticality?
https://en.wikipedia.org/wiki/Californium_neutron_flux_multi...
It works just like a nuclear reactor. Neutron hit U atoms, those split and emit more neutrons in a cascade. The configuration is set up to not be self sustaining. It’s a matter of geometry, enrichment level and such. Therefore it needs a source of neutrons. Cf-252 is such source. It fires neutrons constantly but has a relatively short half life (you have to replenish it yearly or so).
> then wouldn't that require a razor's edge of criticality?
Yup. From the device description in its decommissioning plan:
The CFX was a sub-critical assembly of uranium-2-35 surrounding a Cf-252 source. The function of the U-235 fuel was to multiply the neutrons coming from the Cf-252 source, which fissions spontaneously. The CFX was designed never to exceed a Keff of 0.99. The CFX assembly yielded sufficient neutron fluxes for applications such as neutron activation analysis.
You don't want to know what I keep in my basement ...
(... but it really isn't so interesting, so in order to keep the mystery, I'll simply not say what it is!)
> In 1975, Kodak powered up the country’s first californium neutron flux multiplier (CFX). Though it couldn’t live up to the sci-fi-tinged promise of its name
Why? It vanished! Nobody knows why or how.
As a reminder: MIT has a research reactor smack-dab in the middle of Cambridge. It's like a block or two off of Mass Ave near Central.
They give tours, and if you're in the area, it's highly recommended. A great Boston-area date for the right kind of person.
The article is paywalled, but remember that the USA’s business giants during the Cold War were ran quite different than businesses today, especially with the fact that they had major internal R&D labs that did novel research in-house and relied less on transfer coming from research universities. Think about the other stories that you may have heard about Xerox or Bell labs. So Kodak having research abilities is not surprising. They also made the cameras and films for US spy satellites during the Cold War. They were not just a little company that made recreational film. They were a science and chemistry powerhouse.
When I was at university a lifetime ago, the country had a number of university research reactors. Some of their work could be.. and was.. replaced by computer simulations, but not all. Today there are zero. My impression is that not only is the UK public ignorant and fearful of nuclear, but of "labs" in general. Their view is informed largely by newspaper headlines and Hollywood movies.
Disappointing, for a second I thought I have found a solution to power my 8x5090 homelab.
Quote: "and though it takes roughly 100 pounds of it to build an atomic bomb...”
Are they stupid at PM or just selling misinformation?
This matches other sources on the internet: a bomb requires about 15kg of U-235 [0] with a good use of neutron reflectors, and HEU by definition contains 20%+ of U-235 [1]. We don't know exactly what the U-235 concentration was in the Kodak device, but reasonable values would make the claim "roughly" correct.
[0] https://www.britannica.com/technology/nuclear-weapon/Princip...
At least it wasn't "though it takes at least the equivalent of 12.5 bald eagles of it to build an atomic bomb"
The whole article is a journalistic nothingburger.