9 ms·

Declassified videos of atmospheric nuclear tests (2017)

80 points by kerouanton 8y ago

ValleyOfTheMtns 8y ago
In the final one (Operation Teapot - Turk) there are these criss-crossed diagonal streaks in the background. What are those from?
- deleted 8y ago
  [deleted]
- robin_reala 8y ago
  I haven’t watched it, but probably sounding rockets to measure the blast wave? https://en.wikipedia.org/wiki/Sounding_rocket https://en.wikipedia.org/wiki/Sounding_rocket
  - quicklime 8y ago
    Looks like it, except that the rocket itself isn't taking measurements, it's just there to create a smoke trail which can be analyzed later? http://www.atomcentral.com/atomic-smoke-trails.aspx http://www.atomcentral.com/atomic-smoke-trails.aspx http://nuclearweaponarchive.org/Usa/Tests/SmokeTrails.html http://nuclearweaponarchive.org/Usa/Tests/SmokeTrails.html
    - robin_reala 8y ago
      Yes, exactly. Immediately before detonation you send up rockets in a grid pattern, then film it with high speed cameras. You can then look at the grid deformation over time to get an idea of the shape of blast wave.
rhodrid 8y ago
Such vandalism and for what?
- jonsen 8y ago
  Cold war. Better than hot war.
  - paulie_a 8y ago
    It wasn't exactly a cold war.
    - mrkstu 8y ago
      It was. We are very lucky there was never a direct confrontation between the different sides at the height of their strength. If the USSR and China had been able to create a common cause and gone fully aggressive in the 70s, there would've been a good chance of either a nuclear war or WWIII sweeping the world. That is a hot war.
      - paulie_a 8y ago
        Except for all those pesky wars, Korea, Vietnam, Afghanistan
        Majestic121 8y ago
        Vietnam was 1.5 millions casualties, give or take, civilians included. WW2 was 60 million. It's not about disparaging the importance of Vietnam and all, but the war could have been way hotter than what is was.
      - jacquesm 8y ago
        Tell that to the Vietnamese and the Koreans.
    - dsfyu404ed 8y ago
      It was the middle of winter in the arctic compared to any shooting engagement between the Warsaw Pact nations and NATO. Proxy wars every decade are basically world peace compared to any realistic scenario as to how a shooting war between the major powers would have played out.
Mary-Jane 8y ago
"When he dug in to find out why there was a discrepancy, he discovered that the manual measurements made in the '50s and '60s were off, in some cases by 20 percent to 30 percent." I'd heard that during the war the US exaggerated the power of nuclear weapons but this is the first time I've seen evidence to substantiate the claim. Was the data high or low? I perused the article twice and couldn't find clarification.
billfruit 8y ago
Thinking of nuclear weapons, why is there too little mainstream political support for unilateral nuclear disarmament in western democracies. I do not think there is much necessity for atleast UK and France to keep and further develop nuclear deterrence. For now atleast in UK the major reason for maintenance and renewal of nuclear weapons and their delivery platform seems to be that, they needs to be done lest thousands lose their jobs, which is a reason so out of 'Yes, Prime Minister'.
- Majestic121 8y ago
  Why would UK and France get rid of their nuclear weapon ? It's a pretty good deterrent in case Russia gets a bit too cocky in Europe.
  - secfirstmd 8y ago
    Or the US balks at the idea of going to war with Russia and decides to remove its nuclear Umbrella from Europe/fails to retaliate after a a strike in Europe.
- dsfyu404ed 8y ago
  >Thinking of nuclear weapons, why is there too little mainstream political support for unilateral nuclear disarmament in western democracies. MAD has kept the peace better than anything so far. It may be uncomfortable for a variety of reasons but the fact of the matter is that nuclear powers don't get in shooting wars with each other and nobody picks a fight with a nuclear power no matter how small.
  - billfruit 8y ago
    If say South Africa has done away with nuclear weapons capabilities, then why can't UK? Besides countries like Germany, Italy, Spain, Japan do not have their own nuclear deterrent capabilities.
    - Analemma_ 8y ago
eatbitseveryday 8y ago
I am concerned that uploading the videos to YouTube isn't archiving. I realize they perhaps maintain their own backups of the digitized versions, but one cannot otherwise preserve them by sharing them with the world via YouTube.
- delinka 8y ago
  Presumably, YouTube is merely a distribution point for those amongst us who would make local copies for redundant archival purposes.
  - EA 8y ago
    Subject to the YouTube compression algorithms and meta data changes of course...
  - eatbitseveryday 8y ago
    Downloading videos from YouTube is a violation of their policy, and there is no inherent way to do this from their interface. YouTube (or other video streaming services) are for viewing purposes only, not distribution. I realize perhaps the intention of uploading to YouTube was more to advertise this project, rather than actually archiving it. Distribution should be done via a website with links to files, e.g. ESO's gigapixel mosaic of the central parts of the Milky Way, a full size of 24.6 GiB [1] [1] http://eso.org/public/images/eso1242a/ http://eso.org/public/images/eso1242a/
    - flattone 8y ago
      G Drive would be a better alternative.
    - anticensor 8y ago
      > Downloading videos from YouTube is a violation of their policy Unless it is licensed under Creative Commons, in which case they themselves provide a download button.
    - dylan604 8y ago
dmix 8y ago
> Nuclear detonations show two characteristic light pulses. This double-pulse phenomenon is evident in the video of the “Harlem event,” a 1.2 megaton test that took place 13,645 feet above the Christmas Island area of the Pacific on June 12, 1962. The first pulse peaks almost immediately as the shockwave first forms (0:09 in the video). The brightness then decreases as the superheated air, which is opaque when heated to above 3,300 degrees Kelvin -- or 5,480.33 degrees Fahrenheit -- shields the light from inside the fireball (0:10 in the video). As the shockwave cools to below 3,300 Kelvin, the air becomes transparent and the hot gasses begin to show through, creating the second pulse (0:21 in the video). This is so interesting. I've always noticed the iconic double flashing in nuclear detonations but I never knew why it happened. > Software developed by LLNL computer scientist Jason Bender scans each frame of the films to automate the measurement process. Bender’s software notes the timestamp of both pulses of light, as well as the darkest frame between them. With this data, Spriggs can calculate the test’s yield. Sounds like a fun project, writing algorithms to parse 50yr old classified films of nuclear detonations.
platz 8y ago
> Measurements taken in the '50s and '60s focused on the rate of growth of the fireball. These measurements were done manually by projecting each frame onto a grid, with an analyst jotting down the eyeballed measurement before the projector’s heat began to melt the frame. What?
- dsfyu404ed 8y ago
  The grid on the photo, the camera field of view, the landscape, sounding rocket contrails, etc, etc are all of known size. It's like using a beer can for scale in a photo.
  - platz 8y ago
    Sure, I'm more interested in the "melting the frame" issue
    - magduf 8y ago
      You must be too young to have used a home film projector. Even in a little 8mm projector, the light bulb is very hot, to get the brightness needed. Any film that sits in front of the bulb will simply melt from the heat. The only reason it normally doesn't is because the film is being moved through the projector so quickly that it doesn't have time to get that hot, but when the advancing mechanism gets stuck, it only takes a few seconds for that frame of the film to melt away.
    - implements 8y ago
      Here's a good example - the film was loaded incorrectly and started to burn whenever it slowed down: https://www.youtube.com/watch?v=aCNR6rnl8LQ https://www.youtube.com/watch?v=aCNR6rnl8LQ
- eatbitseveryday 8y ago
  >> before the projector’s heat began to melt the frame. > What? The projector uses a hot lightbulb to display the frame in the film onto a wall or screen. The film sits just in front of this bulb, and of course the heat can risk damaging or melting the plastic film if the film is not quickly accelerated past the bulb (as is the case for watching a video - a sequence of frames). Keeping one frame visible on a wall is to measure the visible size of the fireball, but doing so means one frame stays in front of the bulb long enough to risk it melting.
ryanmercer 8y ago
There's a guy that's digitizing them to get more accurate classifications as to the strength of the blasts and the sad thing is he's finding that some of the canisters are full of basically dust from some of the film disintegrating. :(
- dylan604 8y ago
  probably with a strong smell of vinegar. i've seen my share of damaged film, but you don't even need to see it to know it's damaged just by the smell
julienchastang 8y ago
If you ever get a chance, check out the Smithsonian-affiliated National Atomic Testing Museum in Las Vegas, NV.

80 points by kerouanton 8y ago

In the final one (Operation Teapot - Turk) there are these criss-crossed diagonal streaks in the background. What are those from?

deleted 8y ago
[deleted]
robin_reala 8y ago
I haven’t watched it, but probably sounding rockets to measure the blast wave? https://en.wikipedia.org/wiki/Sounding_rocket https://en.wikipedia.org/wiki/Sounding_rocket
- quicklime 8y ago
  Looks like it, except that the rocket itself isn't taking measurements, it's just there to create a smoke trail which can be analyzed later? http://www.atomcentral.com/atomic-smoke-trails.aspx http://www.atomcentral.com/atomic-smoke-trails.aspx http://nuclearweaponarchive.org/Usa/Tests/SmokeTrails.html http://nuclearweaponarchive.org/Usa/Tests/SmokeTrails.html
  - robin_reala 8y ago
    Yes, exactly. Immediately before detonation you send up rockets in a grid pattern, then film it with high speed cameras. You can then look at the grid deformation over time to get an idea of the shape of blast wave.

rhodrid 8y ago

Such vandalism and for what?

jonsen 8y ago
Cold war. Better than hot war.
- paulie_a 8y ago
  It wasn't exactly a cold war.
  - mrkstu 8y ago
    It was. We are very lucky there was never a direct confrontation between the different sides at the height of their strength. If the USSR and China had been able to create a common cause and gone fully aggressive in the 70s, there would've been a good chance of either a nuclear war or WWIII sweeping the world. That is a hot war.
    - paulie_a 8y ago
      Except for all those pesky wars, Korea, Vietnam, Afghanistan
      - Majestic121 8y ago
        Vietnam was 1.5 millions casualties, give or take, civilians included. WW2 was 60 million. It's not about disparaging the importance of Vietnam and all, but the war could have been way hotter than what is was.
    - jacquesm 8y ago
      Tell that to the Vietnamese and the Koreans.
  - dsfyu404ed 8y ago
    It was the middle of winter in the arctic compared to any shooting engagement between the Warsaw Pact nations and NATO. Proxy wars every decade are basically world peace compared to any realistic scenario as to how a shooting war between the major powers would have played out.

Mary-Jane 8y ago

"When he dug in to find out why there was a discrepancy, he discovered that the manual measurements made in the '50s and '60s were off, in some cases by 20 percent to 30 percent." I'd heard that during the war the US exaggerated the power of nuclear weapons but this is the first time I've seen evidence to substantiate the claim. Was the data high or low? I perused the article twice and couldn't find clarification.

billfruit 8y ago

Thinking of nuclear weapons, why is there too little mainstream political support for unilateral nuclear disarmament in western democracies. I do not think there is much necessity for atleast UK and France to keep and further develop nuclear deterrence. For now atleast in UK the major reason for maintenance and renewal of nuclear weapons and their delivery platform seems to be that, they needs to be done lest thousands lose their jobs, which is a reason so out of 'Yes, Prime Minister'.

Majestic121 8y ago
Why would UK and France get rid of their nuclear weapon ? It's a pretty good deterrent in case Russia gets a bit too cocky in Europe.
- secfirstmd 8y ago
  Or the US balks at the idea of going to war with Russia and decides to remove its nuclear Umbrella from Europe/fails to retaliate after a a strike in Europe.
dsfyu404ed 8y ago
>Thinking of nuclear weapons, why is there too little mainstream political support for unilateral nuclear disarmament in western democracies. MAD has kept the peace better than anything so far. It may be uncomfortable for a variety of reasons but the fact of the matter is that nuclear powers don't get in shooting wars with each other and nobody picks a fight with a nuclear power no matter how small.
- billfruit 8y ago
  If say South Africa has done away with nuclear weapons capabilities, then why can't UK? Besides countries like Germany, Italy, Spain, Japan do not have their own nuclear deterrent capabilities.
  - Analemma_ 8y ago

eatbitseveryday 8y ago

I am concerned that uploading the videos to YouTube isn't archiving. I realize they perhaps maintain their own backups of the digitized versions, but one cannot otherwise preserve them by sharing them with the world via YouTube.

delinka 8y ago
Presumably, YouTube is merely a distribution point for those amongst us who would make local copies for redundant archival purposes.
- EA 8y ago
  Subject to the YouTube compression algorithms and meta data changes of course...
- eatbitseveryday 8y ago
  Downloading videos from YouTube is a violation of their policy, and there is no inherent way to do this from their interface. YouTube (or other video streaming services) are for viewing purposes only, not distribution. I realize perhaps the intention of uploading to YouTube was more to advertise this project, rather than actually archiving it. Distribution should be done via a website with links to files, e.g. ESO's gigapixel mosaic of the central parts of the Milky Way, a full size of 24.6 GiB [1] [1] http://eso.org/public/images/eso1242a/ http://eso.org/public/images/eso1242a/
  - flattone 8y ago
    G Drive would be a better alternative.
  - anticensor 8y ago
    > Downloading videos from YouTube is a violation of their policy Unless it is licensed under Creative Commons, in which case they themselves provide a download button.
  - dylan604 8y ago

dmix 8y ago

> Nuclear detonations show two characteristic light pulses. This double-pulse phenomenon is evident in the video of the “Harlem event,” a 1.2 megaton test that took place 13,645 feet above the Christmas Island area of the Pacific on June 12, 1962. The first pulse peaks almost immediately as the shockwave first forms (0:09 in the video). The brightness then decreases as the superheated air, which is opaque when heated to above 3,300 degrees Kelvin -- or 5,480.33 degrees Fahrenheit -- shields the light from inside the fireball (0:10 in the video). As the shockwave cools to below 3,300 Kelvin, the air becomes transparent and the hot gasses begin to show through, creating the second pulse (0:21 in the video). This is so interesting. I've always noticed the iconic double flashing in nuclear detonations but I never knew why it happened. > Software developed by LLNL computer scientist Jason Bender scans each frame of the films to automate the measurement process. Bender’s software notes the timestamp of both pulses of light, as well as the darkest frame between them. With this data, Spriggs can calculate the test’s yield. Sounds like a fun project, writing algorithms to parse 50yr old classified films of nuclear detonations.

platz 8y ago

> Measurements taken in the '50s and '60s focused on the rate of growth of the fireball. These measurements were done manually by projecting each frame onto a grid, with an analyst jotting down the eyeballed measurement before the projector’s heat began to melt the frame. What?

dsfyu404ed 8y ago
The grid on the photo, the camera field of view, the landscape, sounding rocket contrails, etc, etc are all of known size. It's like using a beer can for scale in a photo.
- platz 8y ago
  Sure, I'm more interested in the "melting the frame" issue
  - magduf 8y ago
    You must be too young to have used a home film projector. Even in a little 8mm projector, the light bulb is very hot, to get the brightness needed. Any film that sits in front of the bulb will simply melt from the heat. The only reason it normally doesn't is because the film is being moved through the projector so quickly that it doesn't have time to get that hot, but when the advancing mechanism gets stuck, it only takes a few seconds for that frame of the film to melt away.
  - implements 8y ago
    Here's a good example - the film was loaded incorrectly and started to burn whenever it slowed down: https://www.youtube.com/watch?v=aCNR6rnl8LQ https://www.youtube.com/watch?v=aCNR6rnl8LQ
eatbitseveryday 8y ago
>> before the projector’s heat began to melt the frame. > What? The projector uses a hot lightbulb to display the frame in the film onto a wall or screen. The film sits just in front of this bulb, and of course the heat can risk damaging or melting the plastic film if the film is not quickly accelerated past the bulb (as is the case for watching a video - a sequence of frames). Keeping one frame visible on a wall is to measure the visible size of the fireball, but doing so means one frame stays in front of the bulb long enough to risk it melting.

ryanmercer 8y ago

There's a guy that's digitizing them to get more accurate classifications as to the strength of the blasts and the sad thing is he's finding that some of the canisters are full of basically dust from some of the film disintegrating. :(

dylan604 8y ago
probably with a strong smell of vinegar. i've seen my share of damaged film, but you don't even need to see it to know it's damaged just by the smell

julienchastang 8y ago

If you ever get a chance, check out the Smithsonian-affiliated National Atomic Testing Museum in Las Vegas, NV.