What causes the vertical smoke stripes during a nuclear explosion?

Question

For example, in these pictures:
http://zvis.com/nuclear/dimg.php3?climax1,upkclimax
http://zvis.com/nuclear/dimg.php3?annie,upkannie

Or this video (2 min)
http://youtube.com/watch?v=non1QFZVE6w&mode=related&search=

I've notice there are 13 or 14 stripes in some pics.
They are caused by the explosion or they correspond to something else?

Answer 1

The vertical stripes are smoke trails from rockets. They are used to signal the speed and distance of shock waves from the nuclear explosion. The smoke trails are not a part of the nuclear explosion.

As the shock wave hits each precisely distanced rocket, it triggers the launch of that rocket full of very smokey fuel. By measuring the time to each rocket launch, observers can measure how fast the shock wave advances from the time of the nuclear blast.

PS: The answer that suggests the rockets are dropped from a plane is way off base. Airplanes do not do well in nuclear blasts...think about it. {From a retired Naval Aviator.}

PPS: The answer that suggested the size of the blast can be guesstimated from the rocket trails is correct. That's the "distance" part I mentioned earlier.

Answer 2

Vertical Explosion

Answer 3

I used to wonder about that myself until I met a person who is familiar with just about everything there is to know about those tests. He told me that those are marker charges, set off to allow the observers to have perspective as to the size of what they were seeing. It was the first explanation that made ANY sense to me. I don't recall the spacing between them, except that it was uniform.

Answer 4

those are smoke flares dropped by planes that go strait down making a straight line so the scientist can measure the shock waves that come from the blast they cant see in clear air. uh yeah and the first bomb was dropped by uh... uh,, oh yeah! the enola gay! an airplane! i i guess they couldn't have dropped smoke flares too! [sarcasm]