Comments on: Rapatronic Nuclear Photographs

By: allanwhite

allanwhite — Wed, 23 Dec 2009 19:03:02 +0000

The “rope trick effect”, as I recall, is the wires fluorescing (essentially turning into plasma) from the gamma (or was it X-ray?) burst, which precedes the visual effects by a few picoseconds (or is it femtoseconds?). I’m sure it’s on wikipedia…

Ehh, just read it, apparently it’s thermal shock.

By: Leighther

Leighther — Mon, 13 Nov 2006 02:18:28 +0000

gypse: I think they used to launch rockets to leave smoke trails in the air before detonating the A-bomb,
the smoke trails would show the effect of the shockwave in the air.

By: gypse

gypse — Thu, 26 Oct 2006 05:35:50 +0000

lol them 3 little lines in the lower right hand corner sorry im at fault i was trying to jump start my space ship where was the engerizer bunny when i needed him??

ps dont mind me just a freak of nature any way but the pic's are pritty cool! gypse.

By: Dayton92

Dayton92 — Tue, 17 Oct 2006 20:56:39 +0000

I’m still puzzled by something in the picture, and I’ve seen it before in photos of nuclear explosions. In bottom righthand quadrant of the picture there are about 5 sort of vertical lines. Now, if I’m understanding the rope trick effect properly, those are the spike-like protrusions on the fireball. So what are these lines we’re seeing? Anybody have an explanation?

By: LBruce

LBruce — Mon, 16 Oct 2006 05:45:06 +0000

I love having the chance to speculate before bothering to learn why it's wrong...

I'd never heard of the Kerr Effect, but a rotation of 90 degs is mentioned for these cameras. Given the intensity of light from a bomb blast, it seems one would only need rotate the polarizati0n the tiniest bit.

By: Drakvil

Drakvil — Sat, 14 Oct 2006 07:35:16 +0000

superdude882 said: "wow didn't realize they were 3times as hot as the sun…question though. how far is the sun from us and how hot is it? i mean with it so far away it's already burning hot on a sunny day, if the bombs are so hot wouldn't they pretty much destroy the earth badly? and the cameras would be able to survive on the sun then? since they can withstand something hotter than 3 suns it should be able to take on one?"

Admiral Dread did a good job providing the temperature you were asking about, so I'll pick up some of the other stuff. The sun is, on average, about 98,000,000 miles from the Earth. The reason a nuke doesn't destroy the Earth with the temperatures generated is that the amount of energy released in total is inconsequential compared to that of the Sun, and is a very localized event. The Sun's diameter is roughly 870,000 miles while the Earth has a diameter of a little under 8,000 miles. So the 2-dimensional area of the photosphere of the sun facing the Earth is roughly 594,166,500,000 square miles - radiating heat at about 5,800K over that entire surface (and the corona of the Sun has temperatures reaching at times up to a million K... and since the corona of the sun is outside of the photosphere, it has an even larger surface area).

The size of the fireball from a nuke is incredibly smaller than that (if it were a 20 mile diameter fireball, the 2D surface area would be 314 miles, or nine decimal places smaller than the Sun and divided by a constant) and maintains that temperature for a very short time. If it were somehow able to maintain that temperature for an extended amount of time, trouble could very well ensue. You can pass your hand through a flame, but the short duration keeps you from getting a burn. Keep your hand there for a minute.... you get the picture.

By: Floj

Floj — Thu, 12 Oct 2006 16:00:54 +0000

Berkana said: ". . . by the way, notice that I didn't need to understand any quantum mechanics to explain that. There is a lot of quantum mechanics involved in the study of polarization effects when you are dealing with individual photons, but polarization is easier than that and easily tractable for the most part if you approach it as a bunch of vectors to be dealt with using trigonometry and the pythagorian theorem."

Ha! Nice Berkana. Einstein once said that if you couldn't explain something to a six year old then you don't truly understand it yourself. That quote was paraphrased but it gets the point across. I'm looking forward to taking some modern physics myself. It'll be fun. Like pie. Alan should get some too. Nothing relieves the stress of a busy schedual like a nice big slice of pumpking pie with double scooped whip cream. mhmm.

By: ickster

ickster — Wed, 11 Oct 2006 16:39:26 +0000

sh0cktopus said: "I'm curious how high-speed photography was used in a project for the postal service. There doesn't seem to be an obvious connection there."

This is just a guess, but it could be related to the optical scanners that were developed for mail sorting. Not quite the same as photography, but to get an image sharp enough to be analyzed by OCR software from an envelope zipping through a slot probably requires a lot of the same kind of expertise.