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Platystemon
Feb 13, 2012

as a person who never leaves my house i've done pretty well for myself.

-Fish- posted:

I'm honestly anticipating cable boxes being phased out in place of boxes which basically just operate the TV app, plus some sort of solid state storage for DVR function, or built in streaming services.

Why would you use solid state storage for that? Hard drives will be obsolete some day, but DVRs might well be one of the last things to use them. They’re cheap and high in capacity, and their main disadvantages, non‐sequential access speed, energy consumption, and intolerance to vibration are non‐issues in this application.

Some cable companies already offer DVR‐esque functionality with the storage on their end, though, and I can only imagine this becoming more popular. Everyone loves the cloud, and in this case it makes a lot of sense to only store each piece of programming once (well, several times for performance reasons, but it’s still better than every Tom, Dick, and Harry having to have their own copy).

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Pilsner
Nov 23, 2002

OttoVonBismarck posted:

A film shot in 1919 can still be played back with modern equipment, while you might struggle to get digital software from just a few decades back to work at all.
Thanks for the informative post, but I can assure you that data, which video and audio is, can always be parsed and read, even 1000 years from now, given that it's not corrupted of course. In this age of information spreading across the world like wildfire and being stored on thousands of servers, it's extremely unlikely that all knowledge about a video and audio encoding format will be lost forever, rendering the data unusable. Even if it did, people can work hard to code a program that can decipher an encoding format.

I also think that digitalization will on average improve any film's lifespan thanks to video websites and file sharing. There'll always be a copy around. Famous last words perhaps, but more likely than having one copy rotting in some archive.

-Fish-
Oct 10, 2005

Glub glub.
Glub glub.

Platystemon posted:

Why would you use solid state storage for that? Hard drives will be obsolete some day, but DVRs might well be one of the last things to use them. They’re cheap and high in capacity, and their main disadvantages, non‐sequential access speed, energy consumption, and intolerance to vibration are non‐issues in this application.

That's fair. I just stated Solid State since it's basically the hot thing out right now.

Mr. Squishy
Mar 22, 2010

A country where you can always get richer.

Monkey Fracas posted:



A cartoon elephant hardly seems appropriate for an educational poster about a chemical weapon.


...unless it is literally a fun chemical weapon...

I like how it states that it causes an increased dopey feeling, because it acknowledges that everybody feels dopey all the time.

strangemusic
Aug 7, 2008

I shield you because I need charge
Is not because I like you or anything!


Mr. Squishy posted:

I like how it states that it causes an increased dopey feeling, because it acknowledges that everybody feels dopey all the time.

Also not coming from a place where hay is grown I have no idea what musty hay smells like, so I guess I'm hosed in case of a phosgene gas attack.

Truck Stop Daddy
Apr 17, 2013

A janitor cleans the bathroom

Muldoon

Pilsner posted:

Thanks for the informative post, but I can assure you that data, which video and audio is, can always be parsed and read, even 1000 years from now, given that it's not corrupted of course. In this age of information spreading across the world like wildfire and being stored on thousands of servers, it's extremely unlikely that all knowledge about a video and audio encoding format will be lost forever, rendering the data unusable. Even if it did, people can work hard to code a program that can decipher an encoding format.

I also think that digitalization will on average improve any film's lifespan thanks to video websites and file sharing. There'll always be a copy around. Famous last words perhaps, but more likely than having one copy rotting in some archive.

Of course we should be able to reverse engineer all this stuff, but it is not really an optimal position to put yourself in. Archives are supposed to guarantee the survival of their collections - archival standards are high. Some rather new video formats are particularly fleeting in nature and are already starting to degrade/disappear. Archives are working against the clock here and will have to find safe (and hopefully proven) preservation standards to utilize. It's really quite complicated, but digital obsolescence is indeed a very real problem for archives. It all comes down to money, or, more often than not, the lack thereof. Preservation is non-commercial and non-profit in 99% of the time, while at the same time being both time consuming and costly. I'm sorry for being a bit general here, but the issue of the transition from analogue to digital is basically a whole field of its own in archiving.

A relatively recent paper discussing some of the key issues in an introductory manner. The bit about data migration covers some interesting stuff. Archiving is basically a field dedicated to preserving originals, and we need to ask ourselves what is lost whenever we migrate data to new formats. (I only skimmed this one, but it was the first one I could find. I could probably dig up some better ones tomorrow if it's of any interest :) )
http://www.amiatechreview.org/V12-05/papers/tadic.pdf

An example of digital obsolescence and the work needed to save the material:
http://en.wikipedia.org/wiki/BBC_Domesday_Project

An older (and probably somewhat dated) paper, touching on a lot of the same issues as Tadic (only skimmed this one as well):
http://besser.tsoa.nyu.edu/howard/Papers/amia-longevity.html

Finally, here's a "manifesto" by FIAF, highlighting some of the issues. While I personally find FIAF to be a bunch of backwards, film snob/elitist dinosaurs, they did touch on some key issues here.:
http://www.fiafnet.org/uk/members/Manifestofulltext.html

EDIT: added some stuff.
EDIT2: added some more stuff.

Truck Stop Daddy has a new favorite as of 03:09 on Jan 11, 2014

gvibes
Jan 18, 2010

Leading us to the promised land (i.e., one tournament win in five years)

Phanatic posted:

One of the early ways of doing color photography used black and white film, but color filters. Others did it before him, but a Russian named Sergey Prokudin-Gorsky is probably the most famous practitioner.

The way this worked is that you'd take three separate exposures of the subject, one through a red filter, one through a green filter, and one through a blue filter. Then the three developed plates could be precisely aligned, and you could either project light through a red filter, a green filter, and a blue filter, and then through the prints to yield a vibrant color projection, or use them to generate color prints with CMY inks. To avoid having to actually load the camera, take a shot, and then repeat that two more times while keeping everything aligned, there were special cameras for this that'd split the incoming light and send it to all three plates at the same time.

The results were pretty spectacular. This one's from 1911:






Maybe this was common knowledge, but I didn't realize this until recently - color digital still photography still uses black and white sensors, overlaid with a multi-color filter - http://en.wikipedia.org/wiki/Bayer_filter.

taiyoko
Jan 10, 2008


-Fish- posted:

:words: about cable

When we first got transitioned to digital cable here, we couldn't get the new digital box to work at all, mystifying even Comcast to the point that they sent out a technician. It wasn't until I happened to say something along the lines of "Would the old filter on the line be messing things up?" that they went out to check, and sure enough, that was the problem. We only had limited basic, so until the digital conversion, the filter on the line had been all that was necessary.

Computer viking
May 30, 2011
Now with less breakage.

gvibes posted:

Maybe this was common knowledge, but I didn't realize this until recently - color digital still photography still uses black and white sensors, overlaid with a multi-color filter - http://en.wikipedia.org/wiki/Bayer_filter.

Scientific photography often does something even closer. We have a couple of microscopes at work that we use for fluorescent antibody images (immunofluorescence) - basically, you decide what different things you want to see in the image (specific proteins and receptors, usually), buy antibodies that will stick to those, tag the antibodies with different fluorescent dyes, and pour the entire lot over your sample. After washing the excess off, put it in the microscope and blast it with UV. On the microscope is a magazine of narrowband filters that will each only pass the color matching a single dye, and a (2mpix, in our case) b/w camera. Play with the settings in the controlling computer for a while, press the button, wait for things to go *chunk-click* a few times, and you get a stack of b/w images that can be merged in false color.

Here's a random image of a few cells, nabbed from Pierce antibodies after a trip to GIS:

(Sadly, the only images we have in papers are kind of uninteresting, and I don't have any of the posters at hand.)

The mars rovers and Hubble do something similar: High-res b/w camera, filters, and multiple exposures. It's not ideal for fast-moving subjects, but it gets you a higher resolution, and the option for studying emissions in specific wavelengths. While the mars rovers carries a red filter, most of the images taken are actually IR/G/B. The IR channel is apparently more interesting, and it's good enough for color photos (of mars, at least).

Computer viking has a new favorite as of 09:47 on Jan 11, 2014

Pilsner
Nov 23, 2002

OttoVonBismarck posted:

An example of digital obsolescence and the work needed to save the material:
http://en.wikipedia.org/wiki/BBC_Domesday_Project
Hah, that's rather tragicomical. You know what they should do? Release all software, hardware specs and data to the internet. Nerds and enthusiasts will keep it updated and going forever, compatible with modern hardware, I bet. Keep things simple, use open standards and keep it compatible with end-user hardware and software.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.

Captain Novolin posted:

My favourite thing about fire grenades (because I will never need to use them) is that Carbon Tetrachloride decomposes into Phosgene when exposed to air at high temperatures. So when the contents of your fire grenade heat up after you, say, throw them at a fire, the room starts smelling like musty hay or freshly cut grass.
Then your lungs stop working because you just filled a room with a fun chemical weapon.

Well, even modern halon-discharge fire suppression systems can produce hydrogen fluoride and hydrogen bromide if the fire's hot enough, and if those get into your lungs they're going to dissolve into the water there to form hydrobromic acid, which is a stronger acid than hydrochloric, and hydrofluoric acid, which is just terrifying. You accept a little toxic chemical release when you're trying to stop a building from burning down. CCl4's problem is that it's toxic even when it's just sitting around or getting spilled accidentally, if you're hanging out in a room that's on fire there's going to be all sorts of nasty poo poo in the air you don't want to breathe anyway.

Platystemon
Feb 13, 2012

as a person who never leaves my house i've done pretty well for myself.
Lost works are hardly an artefact of the digital age.

Yeah, we’ll lose a lot stuff, but so did the ancients. It’s not as if many manuscripts were preserved, either. It’s all copies. At least copying is easy in the information era—too easy, if you ask the entertainment industry.

BBC’s Domesday Project is a particularly bad example, and it’s their own fault. The BBC lost quite a lot of early television episodes, too, all on analogue tape.

Leonardo and Van Gogh chose unstable pigments that caused their works to deteriorate, but in their cases we cared enough to spend millions restoring them. No one is willing to spend a fraction of that preserving the BBC’s project, and rightly so.

The text of the Archimedes Palimpsest was recovered with multispectral imaging. Perhaps historians of the future will use magnetic force microscopes to recover the audio of Rick Astley’s “Never Gonna Give You Up” from an overwritten hard disk. Maybe they’ll find a Rosetta Stone analogue in the form of the same song in MP3, FLAC, and Vorbis. More than likely, though, there will be many copies, and if the software is lost, they can write a new decoder from the original specifications.

Phanatic
Mar 13, 2007

Please don't forget that I am an extremely racist idiot who also has terrible opinions about the Culture series.

Platystemon posted:

Lost works are hardly an artefact of the digital age.

Of course they're not, but it's also not something you avoid just by saying "Digitize it!"

quote:

Yeah, we’ll lose a lot stuff, but so did the ancients.

Oh, well, that's okay then. Huh? The point of archiving is so that you *don't* lose stuff. So you say "It's easy, just go digital!" and when confronted with the problems that arise from it being just...not that easy, your response is "Yeah, we'll lose a lot of stuff." Not losing stuff is the point.

quote:

BBC’s Domesday Project is a particularly bad example, and it’s their own fault.

BBC's Domesday Project is a perfect example. *Yes*, it's their own fault. That's why it's a good example: their approach was cursory and not fully-considered and they ignored legitimate criticisms of their techniques because they thought it was an easy solution.


quote:

The text of the Archimedes Palimpsest was recovered with multispectral imaging.

In *2007*. The original data was destroyed in the 1200s by the Christians. It wasn't until another 400 years had passed that Newton and Leibniz figured out ways to do the stuff Archimedes was doing in the Method. What would the development of human society have looked like if, instead of being consigned to obscurity, we'd developed *calculus* 400 years earlier than we did? What if Archimedes went on to develop it but the work was lost? The point is to archive stuff in such a fashion that it doesn't take heroic efforts and brand-new technologies and a whole lot of money to recover, so that you *don't* have staggeringly important discoveries and valuable data lost to mankind for centuries.


Collateral Damage
Jun 13, 2009

Phanatic posted:

Well, even modern halon-discharge fire suppression systems
Halon systems are pretty far from modern. In fact they probably deserve a post of their own in this thread. Halon fire suppression systems were banned in the US and europe in 1994, largely due to environmental issues. Halon variants are very powerful contributors to ozone depletion and global warming. In the US systems that were installed pre 1994 are allowed to stay in opertion for now. In Europe they were allowed to stay until the end of 2003.

Nowadays fire suppression systems use alternative extinguishing agents, usually Argonite, Inergen or Novec-1230 which are far less dangerous to health and environment.

FM-200 (heptafluoropropane) is another Halon replacement which is popular in marine installations because it's a drop-in replacement for Halon, meaning you don't have to take the ship into dock to rebuild the suppression system, you just switch the gas bottles. While it's safe for the environment, at high temperatures it can decompose into hydrogen flouride (just like Halon) and carbon monoxide which means a room flooded with FM-200 needs to be properly vented before you can go back inside.

Collateral Damage has a new favorite as of 17:48 on Jan 11, 2014

KozmoNaut
Apr 23, 2008

Happiness is a warm
Turbo Plasma Rifle


Collateral Damage posted:

Nowadays fire suppression systems use alternative extinguishing agents, usually Argonite, Inergen or Novec-1230 which are far less dangerous to health and environment.

Yeah, I remember working in the server room at my old job, it had 12 or 16 big Inergen bottles sitting the corner, big overpressure vents in the walls, big "N2ArCO2" warning signs on the doors. The really fun thing is that activation of the system would be loud as gently caress, and would probably startle most people into running full-speed straight for the door.

At which point they would probably pass out due to lack of oxygen :haw:

KozmoNaut has a new favorite as of 19:39 on Jan 11, 2014

Computer viking
May 30, 2011
Now with less breakage.

There's an inergen system in the server room - and there's one detail about it I've wondered about for a while. Outside the door, there's a yellow "break glass, push button" box marked simply "inergen". Is that the "oh poo poo the firewall is a wall of fire" button, or the "oh poo poo, there's people trapped in there and no fire, stop the gas dump" button?

KozmoNaut
Apr 23, 2008

Happiness is a warm
Turbo Plasma Rifle


It activates the system. You can still breathe when it's active, is just a bit like being on a mountain.

Collateral Damage
Jun 13, 2009

You always have a delay between fire alarms going off and gas release, to give people time to evacuate. I've run live tests on our Novec setup at work, and the alarm is so loud and nauseating you can't stay in the room without hearing protection even if you wanted to.

e: All gas suppressant systems are designed to leave the air in the room breathable. The human body is a lot less picky about the O2 concentration than an air-breathing fire is. (Although if there's another source of oxidizer it's a whole different story). Humans can survive on oxygen levels as low as 6% although you risk passing out under 10%. Most common materials don't burn in atmospheres with less than 15% O2.

Collateral Damage has a new favorite as of 20:03 on Jan 11, 2014

Pham Nuwen
Oct 30, 2010



KozmoNaut posted:

It activates the system. You can still breathe when it's active, is just a bit like being on a mountain.

Our FM200 system has a button that will delay the dump as long as the button is held. It's right by the door, presumably so you can wait to see that everyone is out

Rigged Death Trap
Feb 13, 2012

BEEP BEEP BEEP BEEP

also what triggers breathing/gasping reflex is an abundance of CO2, not a lack of Oxygen.

So it would literally be like being high up on a mountain.



(also the startling realization that you can potentially asphyxiate if you open enough bags of chips in a closed space.)

Tsuru
May 12, 2008

Collateral Damage posted:

Halon systems are pretty far from modern. In fact they probably deserve a post of their own in this thread. Halon fire suppression systems were banned in the US and europe in 1994, largely due to environmental issues. Halon variants are very powerful contributors to ozone depletion and global warming. In the US systems that were installed pre 1994 are allowed to stay in opertion for now. In Europe they were allowed to stay until the end of 2003.

Nowadays fire suppression systems use alternative extinguishing agents, usually Argonite, Inergen or Novec-1230 which are far less dangerous to health and environment.

FM-200 (heptafluoropropane) is another Halon replacement which is popular in marine installations because it's a drop-in replacement for Halon, meaning you don't have to take the ship into dock to rebuild the suppression system, you just switch the gas bottles. While it's safe for the environment, at high temperatures it can decompose into hydrogen flouride (just like Halon) and carbon monoxide which means a room flooded with FM-200 needs to be properly vented before you can go back inside.
Aircraft are the only places where you will still find halon fire extinguishers. When they were banned everywhere else aviation was exempted: the same is true for non-RoHS compliant electronics.

DicktheCat
Feb 15, 2011

Collateral Damage posted:

an air-breathing fire

This is a question so silly that it may sound facetious, but I assure you it isn't : is there a kind of fire that doesn't burn oxygen? I know nuclear things like the sun are technically "burning", but I personally don't equate them with fire in the traditional sense. Is that wrong?

I've always been taught that, to snuff a fire, deprive it of oxygen, which is why the chems that burn underwater seem mystifying to me (always figured maybe it was because there is oxygen in water). So, do these things just not need good ol' O2 or what?



Sorry if that's mind numbingly stupid, chemistry and physics are most certainly not my strong suit. :downs:

Sham bam bamina!
Nov 6, 2012

ƨtupid cat
Never mind; forgot something extremely basic. :doh:

Sham bam bamina! has a new favorite as of 22:16 on Jan 11, 2014

One Eye Open
Sep 19, 2006
Am I awake?

OttoVonBismarck posted:


An example of digital obsolescence and the work needed to save the material:
http://en.wikipedia.org/wiki/BBC_Domesday_Project


So all the work I did when I was 10 is on it's way to being lost? :( How depressing.

Moly B. Denum
Oct 26, 2007

DicktheCat posted:

This is a question so silly that it may sound facetious, but I assure you it isn't : is there a kind of fire that doesn't burn oxygen? I know nuclear things like the sun are technically "burning", but I personally don't equate them with fire in the traditional sense. Is that wrong?

I've always been taught that, to snuff a fire, deprive it of oxygen, which is why the chems that burn underwater seem mystifying to me (always figured maybe it was because there is oxygen in water). So, do these things just not need good ol' O2 or what?



Sorry if that's mind numbingly stupid, chemistry and physics are most certainly not my strong suit. :downs:

Oxygen isn't the only oxidizing chemical. Something like Chlorine trifluoride can make just about anything burn, can't be extinguished and reacts violently with water. Some other things that burn under water are a mixture of fuel and oxidizer, like gunpowder.

Platystemon
Feb 13, 2012

as a person who never leaves my house i've done pretty well for myself.

DicktheCat posted:

This is a question so silly that it may sound facetious, but I assure you it isn't : is there a kind of fire that doesn't burn oxygen? I know nuclear things like the sun are technically "burning", but I personally don't equate them with fire in the traditional sense. Is that wrong?

I've always been taught that, to snuff a fire, deprive it of oxygen, which is why the chems that burn underwater seem mystifying to me (always figured maybe it was because there is oxygen in water). So, do these things just not need good ol' O2 or what?

Yes, there are fires that don’t involve oxygen. In chemistry terminology, oxidation isn’t something that only oxygen can do. Oxygen isn’t even the best oxidiser.

Anything will burn in normal air will burn better in an atmosphere of pure oxygen and excellently in a fluorine atmosphere. Fluorine is like oxygen’s big brother.

You don’t need an atmosphere at all to have “burning”, though. Some things contain their own oxidisers. Gunpowder, for instance. You could fire a gun on the Moon if you wanted because the reaction doesn’t require outside oxygen—it couldn’t, because then the reaction couldn’t happen fast enough. In gunpowder’s case, it happens to contain actual oxygen, but there are plenty of explosives that do not. Silver azide come to mind, it just comes apart into pure nitrogen gas and silver dust.

The Sun, by the way, isn’t burning. It’s undergoing a nuclear reaction. Burning is just an analogy used in school.

Sham bam bamina!
Nov 6, 2012

ƨtupid cat

Moly B. Denum posted:

Oxygen isn't the only oxidizing chemical. Something like Chlorine trifluoride can make just about anything burn, can't be extinguished and reacts violently with water. Some other things that burn under water are a mixture of fuel and oxidizer, like gunpowder.
Oh, duh. Doesn't potassium do that too?

Platystemon
Feb 13, 2012

as a person who never leaves my house i've done pretty well for myself.

Sham bam bamina! posted:

Oh, duh. Doesn't potassium do that too?

Potassium is on the opposite side of the spectrum. It reacts with water because the oxygen from the water molecules breaks with the hydrogen and bonds with the potassium instead.

Geoj
May 28, 2008

BITTER POOR PERSON

Sham bam bamina! posted:

Oh, duh. Doesn't potassium do that too?

Potassium (any of the alkali group, really) reacts so violently with water that it breaks the water molecules down into hydrogen and oxygen. It can't maintain a reaction by itself (say, in a vacuum) but its so reactive to everything else that it explodes unless contained in a very inert substance or a vacuum.

Collateral Damage
Jun 13, 2009

Platystemon posted:

Silver azide come to mind, it just comes apart into pure nitrogen gas and silver dust.
Which reminds me of one of my favorite quotes from the excellent blog Things I Won't Work With. The latest entry actually talks about azides and their delightful detonation-riddled history.

quote:

[...] several sections of this blog category could just as accurately be called Things That Suddenly Want To Turn Back Into Elemental Nitrogen. And thermodynamically, there aren't many gently sloping paths down to nitrogen gas, unfortunately.

And yeah, by air-breathing fire I meant a fire that relies on oxygen from the air, as opposed to all the other delightful kinds of fire you can get when chemists with a poor sense of self preservation get their hands in the toy box.

Zonekeeper
Oct 27, 2007




Man, I love that blog. When people think of dangerous chemicals, they think of simple acids and explosive compounds. But there are things out there that are orders of magnitude worse than that. Things that literally explode when you look at them wrong. Things will burn through every piece of "safety equipment" in a lab (including the concrete foundation of the building). Things that will kill you painfully if so much as a drop falls on your gloved hand. :science:

GWBBQ
Jan 2, 2005


In a fluorine-rich environment, you can even burn water.

Zemyla
Aug 6, 2008

I'll take her off your hands. Pleasure doing business with you!
Also, magnesium, once set alight, will burn in just about anything that isn't a noble gas.

In oxygen:
2Mg(s) + O₂(g) → 2MgO(s)

In water:
Mg(s) + H₂O(aq) → MgO(s) + H₂(g)

In carbon dioxide:
2Mg(s) + CO₂(g) -> 2MgO(s) + C(s)

In nitrogen:
3Mg(s) + N₂(g) → Mg₃N₂

Burning magnesium will even pull the halogens off halon gas. The most effective way to stop a magnesium fire is with dry powders, like sodium chloride, sodium carbonate, and graphite.

Smiling Jack
Dec 2, 2001

I sucked a dick for bus fare and then I walked home.

I forget if it was in Things I Won't Work With or Ignition! but someone developed a compound so sensitive it exploded if you shone a bright light on it.

Collateral Damage
Jun 13, 2009

Rigged Death Trap posted:

also what triggers breathing/gasping reflex is an abundance of CO2, not a lack of Oxygen.
Which is why Inergen contains 8% carbon dioxide. If you're trapped in a room flooded with Inergen it's designed to make you breathe harder so you get more of the remaining oxygen.

GWBBQ
Jan 2, 2005


Smiling Jack posted:

I forget if it was in Things I Won't Work With or Ignition! but someone developed a compound so sensitive it exploded if you shone a bright light on it.
C2N14
http://pipeline.corante.com/archives/2013/01/09/things_i_wont_work_with_azidoazide_azides_more_or_less.php

On a related note, silver fulminate can't be stored in a pure form because it will detonate under its own weight.

KozmoNaut
Apr 23, 2008

Happiness is a warm
Turbo Plasma Rifle


Collateral Damage posted:

Which is why Inergen contains 8% carbon dioxide. If you're trapped in a room flooded with Inergen it's designed to make you breathe harder so you get more of the remaining oxygen.

I didn't know that. Neat!

Rigged Death Trap
Feb 13, 2012

BEEP BEEP BEEP BEEP

Moly B. Denum posted:

Oxygen isn't the only oxidizing chemical. Something like Chlorine trifluoride can make just about anything burn, can't be extinguished and reacts violently with water. Some other things that burn under water are a mixture of fuel and oxidizer, like gunpowder.

Hah!
This lovely Stuff.
https://www.youtube.com/watch?v=M4l56AfUTnQ

in order posted:

'Plexiglas, a rubber glove, clean leather, not-so-clean leather, a gas mask, a piece of wood, and a wet glove'
:allears:

Also from The amazing blog:

Crazy rear end Chemists (can't believe I wanted to be one) posted:

There’s a report from the early 1950s (in this PDF) of a one-ton spill of the stuff. It burned its way through a foot of concrete floor and chewed up another meter of sand and gravel beneath, completing a day that I'm sure no one involved ever forgot. That process, I should add, would necessarily have been accompanied by copious amounts of horribly toxic and corrosive by-products: it’s bad enough when your reagent ignites wet sand, but the clouds of hot hydrofluoric acid are your special door prize if you’re foolhardy enough to hang around and watch the fireworks.


So yes. There are things which cannot exist in nature because their own existence causes them to violently cease existing as a whole.
Humans have crazy levels of Hubris.



[e]:VVVV Rail guns are of much superior utility. Not much way to get rid of heat in space unfortunately.

Rigged Death Trap has a new favorite as of 01:13 on Jan 12, 2014

Hogge Wild
Aug 21, 2012

by FactsAreUseless
Pillbug

Platystemon posted:

You don’t need an atmosphere at all to have “burning”, though. Some things contain their own oxidisers. Gunpowder, for instance. You could fire a gun on the Moon if you wanted because the reaction doesn’t require outside oxygen—it couldn’t, because then the reaction couldn’t happen fast enough. In gunpowder’s case, it happens to contain actual oxygen, but there are plenty of explosives that do not. Silver azide come to mind, it just comes apart into pure nitrogen gas and silver dust.

drat! So you are saying that spaceships could fight each other by using muzzleloaded black powder cannons :pirate:?

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GWBBQ
Jan 2, 2005


This has been a fun enough derail that I think it deserves its own thread. Let's take the talk of non-obsolete chemicals to Things that go FOOF in the night

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