[gggggg5]

I was rather baffled by so many sources claiming that this would be super difficult to find.

It seemed like such a simple task to drive up and down roads with some radiation detection equipment, log the data and investigate any hotspots.

Well, I guess it was? Or maybe I'm severely underestimating the complexity of this?

[hilbert42]

The news was a bit of a beat-up and the chances of just accidentally stumbling on it out there were pretty remote to essentially nil. But what's authority to do? If some kid had found it and took it to school there'd be hell to play.

Based of its stated radiation signature it was always going to be easy to find. Right, it was a simple but nuisance task and took about as long as expected.

[d-z-m]

> hell to play.

not sure if this was a typo, but the phrase I'm familiar with is "hell to pay".

https://dictionary.cambridge.org/us/dictionary/english/there...

[hilbert42]

Yeah, another damn typo I've missed, it's embarrassing. I understand the correct phrase.

Last week, I wrote 'we all cropped it' instead of 'we all copped it' which makes no sense—yet I reread that text three times, twice before posting and once thereafter and yet I still missed it.

I wish HN would allow typographical corrections past the usual edit deadline. Bad typos distract so they reduce the impact of what one is trying to say.

Thanks for pointing it out.

[HPsquared]

It was probably a mistake to report it to the public while it was still missing. That probably attracted a bunch of amateurs who could have ended up finding it. Far safer to look for it quietly first.

[laci37]

I guess that was because they were afraid of it getting stuck in a tire. If I found a strange metal cylinder in my tires, I would probably pick it up a try to find out what it is.

[HPsquared]

Did they close the road and/or put a checkpoint in place? That'd eliminate that risk.

[prollings]

The road you're talking about was 1400km long

[bell-cot]

1400km / (70km/h) = 20 hours of driving. This was no "a thousand volunteers on foot spent days searching for even a scrap of evidence" effort.

[rmccue]

Pretty sure it's also the only road connecting a lot of these places; this is far remote WA.

[zoklet-enjoyer]

I was considering going on a vacation/scavenger hunt when I saw the first article about it

[curiousgal]

Well imagine if the pellet fell on the road, another car drove by and the pellet got stuck in one of the car's tire grooves. The car eventually makes it to a parking lot, or to the back of someone's ranch. Good luck finding it, short of monitoring hospitals for radiation poisoning patients.

[maven29]

Perhaps a nation-wide campaign to cover your phone camera lens with tape and then look for artifacts from gamma rays hitting the CMOS sensor?

[hilbert42]

Well, that's one way. Monitoring/surveillance cameras in hot spots in nuclear facilities are often known to have horrible fuzzy images (sometimes it's difficult to see what's being monitored).

It's an interesting question how close one would have to get for the CMOS sensor to register notably in this instance. Given the stated radiation signature of this sample it's likely one would have to get pretty close, so it may not be a useful technique.

I can't recall having read anything about smartphone CMOS sensors and radiation thresholds so I'd be interested in hearing from anyone whose knowledgeable about the matter.

[dsfyu404ed]

You might as well make up a story about a kangaroo eating it and then someone hunting and eating the 'roo.

The odds for any one small object to get not only picked up but picked up and not tossed back out are astronomically tiny.

[throwbadubadu]

In some other thread I believe someone said with his known equipment, even if not occluded, a scan would take some seconds... so with that wouldn't have been to be that easy? So now not sure if normal.or amazing that they can do this with a 70km/h drive by?!

( Edit: https://news.ycombinator.com/item?id=34623782 sounds like not too amazing :) )

[defrost]

It's not too amazing.

Perth has a few companies that do this work for a living - as a grind job, flying contracts for an actuall million line kilometres of 256 channel radiometric mapping at anything from $7 to $15 AU per line kilometre for mineral exploration.

This has been ongoing for 50 years (see: Radiometric Map of Australia) and I'm slighlty baffled why a plane wasn't flown along the road on day one.

Realistic guesses are that all airframes were fully booked AND the national agencies wanted to shine and test their new gadget.

It's slightly complex gear to set up - but no more so than properly running the lines for a concert from pickups to to desk to foldback and main speakers, etc. If you can do one you can do the other.

Complicated is when you go and map some area in India near the Pakistan border and suddenly a surprise nuclear test happens beneath you .. which happened to one local crew .. but that's a whole other story.

[fghorow]

Your guess about the airframes being booked has a ring of truth to it. I hadn't thought of that, and was wondering why radiometrics wasn't being used from the beginning.

[wnkrshm]

I want to know this other story, I haven't found it by cursory search - what should I be searching for?

[defrost]

Pokhran-II was a series of five nuclear bomb test explosions conducted by India in May 1998, Pakistan responded with six underground nuclear tests at the Chagai and Kharan test site conducted fifteen days after India's last test.

It was all abit unexpected at the time and the US was interested to know how it came to be that Australians were present.

[albert_e]

I am sorry I am not following the connection between Pokhran-II nuclear tests and Australia. Would you mind sharing some more information or a link maybe?

[defrost]

An Australian radiometric survey team were there at the time over the area during the first detonation .. and for the rest of the series.

Things got ... interesting.

[MockObject]

It sounds like a fascinating story indeed, but I can't find anything about it after a search.

[gtirloni]

> the national agencies wanted to shine and test their new gadget

Exactly. After reading the press release and how they promote their device, I'm not so sure this wasn't deliberate.

[xrayarx]

My thought exactly

[xrayarx]

What I don't understand is, what kind of technology is it? It is obviously great. The technical explanation is not there

[defrost]

The simplest spectrometer is dark sealed tubes of doped sodium iodide crytals with a counter at the ends.

When an energetic gama burst hits a bit of crystal it flashes in a manner that gives up the energy .. over the course of a second and a few thousand events (normal background radiation) you have a spectrum [1].

You no have an indication of all the radiation all arounf the tube.

All around. With no indication of direction. Literally they could have come from anywhere, up, down, left, right, behind you, etc.

What we have here appears to be a vertical tube (or tubes) with mobile masking templates that rotate about and provide some axis of ingress information coupled with any energetic flahes that appear at the same instant.

There is some topographical statistics that needs to be performed and overall there are reduced signal levels (as some incoming gammas are masked and never make a flash) but you can end up with a positional image of where various radiation sources are in the space about the tube.

The other wrinkle they gloss over ('compressed', 'needs fewer counts') suggests (it's either obfuscated or I haven't read deeply enough) they have an eigen library of responses (ie. mean Australian background, Pure Potassium, Pure Uranium, Pure Thorium, Cs-137) baked in to facilitate faster recognition of spectrum patterns.

It's a pattern matching in N^256 type problem in a space that reduces to about N^11 or so when an SVD is applied .. and there are ways to "cheat" and do this faster on the fly.

[1] https://en.wikipedia.org/wiki/Gamma_spectroscopy

[idiocrat]

Last month I have ordered this pocket scintillator/spectroscope "Radiacode-101" from a Cyprus sales company.

https://radiascan.com/products/detector-of-ionising-radiatio...

The waiting time is few months, so I hope the toy arrives eventually.

[noja]

Depends if the wind blows it away.

[defrost]

It's steel around a ceramic slug mix doped with Cs-137 .. think about cutting 8mm off the end of a 6mm diameter steel bolt and dropping that to the ground.

It's going to take a good wind to blow that very far.

[jacquesm]

Especially once it drops a little bit below grade. Or gets covered with a bit of sand on the windward side. Unless picked up it was never going to be more than a few meters away from where it was lost.

I'd love to see some re-enactments and the spread of the spots where the pallet ended up after being lost on step one, that might give some indication as to whether it was found near its original landing point or further away from it.

[adwww]

Or a radioactive magpie.

[mschuster91]

The problem was the unclear scope - it was not sure if the capsule didn't get stuck into someone's tire, an animal ate or played with it, or if it got damaged by a car running over it.

[jjtheblunt]

they were initially concerned it would lodge in a knobby truck tire's treads and be carried off the known path, or so i read.