To save HN a search: a stable isotope used as a neutron capture target, to produce lutetium-177[i], used in targeted radioligand therapies[ii]. Discussed once on HN[iii].
[i] https://isotopes.gov/Ytterbium-176_is_Available_Now
[ii] https://en.wikipedia.org/wiki/Lutetium_(177Lu)_vipivotide_te...
[iii] https://news.ycombinator.com/item?id=40690196 ("Radioactive drugs strike cancer with precision (knowablemagazine.org)")
What has changed here to make them competitive again? Or are they counting on selling small quantities at close to any cost for R&D reactors?
Speaking of which, whatever happened to laser enrichment? That was apparently very promising at some point?
The article has to be read carefully. "On Actinide's engineering estimates, a single Fortitude machine would provide roughly half the isotope-separation capacity of the U.S. government's current electromagnetic fleet."
The "U.S. government's current electromagnetic fleet" is tiny. Oak Ridge is building a modest plant.[1] Idaho has a benchtop-sized separator. That's what Actinide is comparing against. Not the rows of basketball court sized calutrons from WWII. So the announcement gives the impression of a larger operation than it really is.
> Speaking of which, whatever happened to laser enrichment? That was apparently very promising at some point?
That is a very good question. A company called Silex, and their subsidiary Global Laser Enrichment, has been trying to commercialize this for years.[3][4] Exactly how they do this is classified.[5]
There's another startup in this area, crawling along, underfunded, but building something.[6]
Meanwhile, URENCO continues to operate a centrifuge plant in New Mexico.[7] URENCO is a a European company, and seems to be the leader in centifuge technology. Units in France, Germany, the Netherlands, and the US.
I've been expecting something big to happen in the laser enrichment area since the 1990s, but it never has. This suggest that it either doesn't work very well or is being suppressed because it works too well.
[1] https://www.energy.gov/science/articles/doe-expands-stable-i...
[2] https://inldigitallibrary.inl.gov/content/uploads/50/2026/04...
>"A centrifuge plant does one thing, costs billions, and takes years to stand up. Our machines cost a few hundred thousand dollars, produce material within months, deploy anywhere, and are able to be reconfigured in a matter of days to separate various isotopes as they are needed," said Robert Mendelsohn, co-founder and CTO of Actinide.
Nothing. This is a company that specializes in making medical isotopes, which is something Calutrons are good for - you need high levels of enrichment in a single step, you don't need to process large quantities, and the energy consumption doesn't matter. Any talk of using it for reactor fuel production is pure PR spin.
https://en.wikipedia.org/wiki/Separation_of_isotopes_by_lase...
So calutrons will always be less energy efficient than centrifuges, but if the capital cost and construction time is low enough, calutrons might still be economically viable.
The other thing is that for a nuclear reactor, you need many kilograms of uranium. But for a Pluvicto patient, you need less than a gram of ytterbium.
Anyways, I didn't mean to downplay it.
yes, i'd have expected that laser enrichment would be more preferable technology for modern development
Calutrons are using the same principle of separating ions by their mass/charge ratio, just in a preparative scale (you want to collect what is separated) rather than analytical (you just want to know how much of what).
A mass spec used as an instrument measures the components of a substance, this is just the same concept for actual separation of components not just to look at them
https://www.globenewswire.com/news-release/2026/08/26/335139...
This severely reduces the "breakout time" the international community relies on to detect and stop nuclear proliferation.
For nations with enrichment capabilities, enrichment is not a major contributor to overall breakout time. Enrichment doesn't take much time, it's building enrichment facilities that takes a while, especially clandestinely.
It is mostly a matter of money and international politics now. It takes a significant amount of money to build and power, and it is hard to hide the scale of building and power usage from international watchdogs. Because nothing consumes tons of energy and doesn't output tons of product to sell except for nuclear material refinement for weapons.
Until datacenters
Lot's of non-nuclear weapons states do have access, the Netherlands for example enriches more uranium annually than the UK. It's the components of centrifuges that are tightly controlled. Building enrichment facilities is well within the capabilities of pretty much any nation state, it's doing it secretly which is the hard part.
This alternative technique only makes sense at extremely small quantities. For their primary market of making medical isotopes, it makes a lot of sense. For nuclear reactor fuel it's incredibly impractical.
It's not that difficult from an engineering perspective, the tech is almost a century old. It's just that we will drop bombs on anyone who tries.
Nuclear nonproliferation relies on active enforcement.
I don't recall us bombing Pakistan, India, Israel, China, or North Korea.
> Nuclear nonproliferation relies on active enforcement.
The comedy hour at HN has arrived. See above ^^^
There are many, many steps before "drop bombs".
low-enrichment (~20%) is what's happening here.
the bad stuff, for nukes, is ~90% enrichment.
For example you need 100kg of 60% enriched Uranium-235
https://www.researchgate.net/figure/Critical-mass-of-a-bare-...
https://world-nuclear.org/information-library/nuclear-fuel-c...
Hence there technically being no enrichment cap for any country that signed the NPT and stuff (not to be confused with protection from US bombs or rogue states that never signed the NPT).
At least uranium isn’t actually all that radioactive.
Technologies which have low energy consumption and need only small space and therefor are easier to hide, such Laser isotope separation, US wants to restrict to any country, even allies.
It can do, but won't do so reliably; and the guessing it does if it's not grounding with a search is still like someone in a pub saying "I recon…". Admittedly, a Cambridge pub like the Carlton Arms used to be when I lived there (sometimes I'd be the only one at the table who wasn't studying for a PhD), but still, pub.
I ONLY want to hear first person _human_ experiences.
Jfc mate
As far as i know, USA was seriously considering doing this in 1964. However the soviets said that would mean war, so they didn't.
North Korea is so firmly in China and Russia's sphere of influence that bombing them would be hard, especially given how much conventional weapons they have pointed at south korea. That said, would you really want to be north korea? economic warfare has done a number on them. in many ways they are the poster child for nuke != winning.
Israel probably snuck through by doing it early enough and secretively enough that it was fait accompli. They probably tested their nukes before the nuclear non proliferation treaty was even signed.
so really you have india and pakistan. The fact there are so few exceptions kind of proves the system works.
> Nuclear nonproliferation relies on active enforcement.
It relies on getting nukes being an irrational move for most countries. Yes part of that is your enemies will start preventive wars to stop that. A very major part of it is the economic consequences of developing nukes is usually not worth it. Part of it is the smart strategy is to just do most of the work and stop before getting nukes - if shit hits the fan you can get nukes quickly, but going up to the line without crossing it has none of the negative consequences.
"Twenty-six years after the nuclear tests at Pokhran in May 1998 led to an embargo on several Indian atomic energy companies, the US is set to lift the sanctions, opening the route for closer cooperation in the civil-nuclear sector."
https://www.tribuneindia.com/news/india/26-years-after-pokhr...
Iraq, Libya and Venezuela don't have powerful friends willing to go to bat for them.
pakistan and india did it in secret.
incidentally, its alleged that one of the countries on that list killed a very prominent american in order to prevent us from stopping them from creating a nuclear program.
"Following the atomic bombing of Hiroshima in August 1945, R. S. Krishnan, a nuclear physicist who had studied under Norman Feather and John Cockcroft, and who recognised the massive energy-generating potential of uranium, observed, "If the tremendous energy released from atomic explosions is made available to drive machinery, etc., it will bring about an industrial revolution of a far-reaching character." He further noted, however, the difficulties in harnessing nuclear power for peaceful usage, "...a great deal more research work is needed before atomic power can be put to industrial use."
"In March 1946, the Board of Scientific and Industrial Research (BSIR), under the Council of Scientific and Industrial Research (CSIR), set up an Atomic Research Committee under Bhabha's leadership to explore India's atomic energy resources and to suggest ways to develop and harness them, along with establishing contacts with similar organisations in other nations."
https://en.wikipedia.org/wiki/Nuclear_power_in_India
US didn't much opose the nuclear programs in Pakistan and Israel (probably even supported nuclear program in Israel).
https://en.wikipedia.org/wiki/Apollo_affair
US bombed North Korea a lot.