Strange crystals found inside wreckage from the first nuclear bomb test • Hacker News Board

Re: Strange crystals found inside wreckage from the first nuclear bomb test

#71

Post by adrian_b » Mon, May 18, 2026, 5:22 PM UTC

frereubu wrote: post #28

> The clathrate’s “cage” shapes are 12-sided dodecahedrons and 14-sided tetrakaidecahedrons made of silicon atoms... Totally OT but if "dodeca" means 12, why isn't 14 just "tetradeca"? What's the "kai" for?

For the same reason why in English 12 = twelve, but 14 = fourteen. Not all numerals are formed by the same rule.

The correspondents of the -teen numbers in Greek were formed similarly with English, after the model of 14 = four and ten = "tetrakaideka".

"Tetrakaideka" is a contracted form of 14, normally used in compound words. When "14" was an isolated word, it would have been "tettarakaideka" or "tessarakaideka". These are the forms for the neuter gender, the numeral "4" = "tettara" or "tessara" (depending on the dialect) was changed by declension for other genders and cases.

In Ancient Greek numbers bigger than 20, the word "and" = "kai" was usually omitted, but then the bigger number was always the first like in "twenty-four". When "and" was inserted, then the order could also be inverse, like in "four-and-twenty".

Re: Strange crystals found inside wreckage from the first nuclear bomb test

#72

Post by NoMoreNicksLeft » Mon, May 18, 2026, 5:29 PM UTC

frereubu wrote: post #28

> The clathrate’s “cage” shapes are 12-sided dodecahedrons and 14-sided tetrakaidecahedrons made of silicon atoms... Totally OT but if "dodeca" means 12, why isn't 14 just "tetradeca"? What's the "kai" for?

Because the Greek word for 12 is something like "though-theka". And the word for 14 is "theka-tessera". Like most European languages, 11 and 12 are special, then it reverts to the "single digit - ten" or "ten - single digit" pattern.

"kai" is "and" in Greek.

Re: Strange crystals found inside wreckage from the first nuclear bomb test

#73

Post by NoMoreNicksLeft » Mon, May 18, 2026, 5:31 PM UTC

autoexec wrote: post #16

> The only other known naturally forming quasicrystal was found inside meteorite fragments Does it really count as "naturally forming" if we had to artificially construct and detonate a nuke during a carefully conducted experiment to create this one?

If a beaver constructed and detonated the nuke, it'd still just be natural though.

Re: Strange crystals found inside wreckage from the first nuclear bomb test

#74

Post by eesmith » Mon, May 18, 2026, 5:45 PM UTC

therwex wrote: post #67

kombookcha wrote: post #29

Earlier quoted context omitted.

Adding to this, I seem to recall that the specific geological/chemical conditions on the site is consequential for the sorts of glass produced. So presumably, Hiroshmiaite and Trinitite would actually be physically distinct as a material. As I recall, research on meteorite impacts use the similarly formed Impactite to deduce various things about ancient impact sites. As an aside, I think they also do really elaborate…

Probably no Hiroshiaite as the explosion there was at higher altitude of 580 meters. Trinity explosion was close to the desert surface (30 meters). The radius of trinite formation was about 300 meters around the tower so none would have formed at Hiroshima.

I think it's pretty surprising for you to make that "Probably no Hiroshiaite" claim given that the linked-to Wikipedia article says it exists: "Following the atomic bombing of Hiroshima, it was discovered in 2016 that between 0.6% and 2.5% of sand on local beaches was fused glass spheres formed during the bombing." - https://en.wikipedia.org/wiki/Trinitite#Similar_materials

and when a quick search finds the relevant research paper at https://www.sciencedirect.com/science/article/abs/pii/S22133...

"A complex association of millimeter-sized, aerodynamically-shaped debris, including glass spherules, glass filaments, and composite-fused melt particles was recovered from beach sands on the shores of the Motoujina Peninsula in Hiroshima Bay, Japan. .... This study interprets the large volumes of fallout debris generated under extreme temperature conditions as products of the Hiroshima August 6th, 1945 atomic bomb aerial detonation. The chemical composition of the melt debris provides clues to their origin, particularly with regard to city building materials. This study is the first published record and description of fallout resulting from the destruction of an urban environment by atomic bombing."

and when the dynamics are described in https://www.sciencedirect.com/science/article/pii/S0012821X2...

"Our analyses support the hypothesis that the Hiroshima glasses are gas phase condensates formed in the nuclear fireball ... The Hiroshima bomb exploded 580 m above the city so that no crater was formed at the surface. The plasma (called fireball) formed at this altitude, had a maximal radius of 230 m (Imanaka,2011; Malik, 1985). ... The maximum temperature on the ground during the explosion was estimated to be 6287°C (thermal wave) (Radvanec, 2009) while the maximum pressure reached 35 tons per m² (3171 bar) at the arrival of the blast wave at the hypocenter, 1.3s after the explosion (Radvanec, 2009). Under such conditions, the city materials were injected as vapor or melted debris in the air 0.5 to 2 seconds after the explosion and vaporized by the high temperatures prevailing in the plasma (4000-2500 K) at that time (Adams et al., 1960, Supplementary S6)."

I think what your analysis didn't consider was the observation that "The fact that no crater was produced by the explosion (Glasstone & Dolan, 1977) reinforce the idea that the primary source of Hiroshima glasses is the city materials and not the soils or the basement rocks below the city."

Re: Strange crystals found inside wreckage from the first nuclear bomb test

#75

Post by rationalist » Mon, May 18, 2026, 6:57 PM UTC

autoexec wrote: post #16

> The only other known naturally forming quasicrystal was found inside meteorite fragments Does it really count as "naturally forming" if we had to artificially construct and detonate a nuke during a carefully conducted experiment to create this one?

How do we know the quasicrystals in the meteorite fragments are naturally occurring, and weren't created by nuclear detonations on an alien planet, then blasted off into space when an asteroid hit the site? Or perhaps the nuclear explosion was tested on an asteroid rather than a planet.

Re: Strange crystals found inside wreckage from the first nuclear bomb test

#76

Post by gapan » Mon, May 18, 2026, 7:25 PM UTC

beeforpork wrote: post #48

gapan wrote: post #35

Earlier quoted context omitted.

As the sibling comment already said "kai" (pronounced ke like in keg) just means "and". So it literally means 4 and 10 sides in greek. But I have often seen it written as τετραδεκάεδρο (tetradecahedron) in greek as well, so without the kai part. I'm not sure why it is 4 and 10 instead of 14 though. It would be more natural in greek that way (δεκατετράεδρο - decatetrahedron). Maybe it is for putting the distinctive pa…

> "kai" (pronounced ke like in keg) Ancient Greek spans several centuries of sound shifts and many dialects. It cannot easily be simplified into one specific pronunciation, particularly not one that is based on your specific dialect of English. Wiktionary has /kǎi̯/, /ˈkɛ/, /ˈcɛ/ and /ˈce/ for "καὶ".

You don't have to span several centuries to witness that. "και" is pronounced in several different ways in modern greek as well. But that's besides my original point.

Re: Strange crystals found inside wreckage from the first nuclear bomb test

#77

Post by LAsteNERD » Mon, May 18, 2026, 7:30 PM UTC

lightsighter wrote: post #14

dmurray wrote: post #10

What was special about the first nuclear test, rather than the thousands of others, at least hundreds of which were also in the Nevada desert? Obviously it's historically significant, and the new forms of matter were first discovered there , so that's why trinitite is named after the site. But 80 years later, wouldn't we expect the other bomb sites to have just as many interesting chemical reactions?

The Trinity test took place in New Mexico, not Nevada.

Trinity: https://www.lanl.gov/media/publications/1663/0922-revising-t...

Re: Strange crystals found inside wreckage from the first nuclear bomb test

#78

Post by anthk » Mon, May 18, 2026, 7:48 PM UTC

dylan604 wrote: post #56

shagie wrote: post #52

Earlier quoted context omitted.

French has some weirdness to its counting. 11 - 16 is specific words, 17 - 19 is "ten {number}" (dix-sept, dix-huit, dix-neuf). There's also some fun when you get to 70... which is soixante-dix (sixty ten)... and 80 which is quatre-vingts (four twenties)... and 90 as quatre-vingt-dix (four twenties ten). Some dialects of French outside of France have changed how they count.

With Spanish being similar with distinct words for 11-15 with 16-19 being 10+number. Taking Spanish in high school made me consider that for the first time while never having thought about 11,12 being similar in English until that same thought process.

On_ce, do_ce, tre_ce, cator_ce, quinc_e seem to share similar Latin roots with uno, dos, tres, cuatro, cinco...

Re: Strange crystals found inside wreckage from the first nuclear bomb test

#79

Post by kridsdale1 » Mon, May 18, 2026, 8:38 PM UTC

emptybits wrote: post #68

> "a quasicrystal — a kind of matter scientists once thought impossible that challenges traditional ideas about how solids form" Whenever I read a phrase about scientists observing something they thought was impossible ... I get really excited for scientists in that field! :-)

Science advances one “huh, that’s weird” at a time.

Re: Strange crystals found inside wreckage from the first nuclear bomb test

#80

Post by kridsdale1 » Mon, May 18, 2026, 8:43 PM UTC

theowaway wrote: post #39

pocksuppet wrote: post #25

Earlier quoted context omitted.

Well, it's more natural than something like a lab diamond. This one forms naturally given unnaturally created, but not completely implausible, conditions. There is a big difference between "we blew up rocks and they formed this mineral" and "we treated rocks with X acid and Y acid and then carefully annealed them under extreme pressure and they formed this mineral"

De Beers has entered the chat

You don’t really love your wife unless you’re willing to detonate a nuclear device and wait for the half-life.