Re: What are the white, vertical lines seen adjacent to some atomic explosions?

Peter, 

I checked out the website and I was fairly certain that I remembered what 
they were, but I went ahead and emailed them to be certain and infact they 
were the smoke trails of rockets.  The answer I received is below.  

For several blasts, the testers would fire rockets just before the warhead
was exploded. The smoke trails provided an easier method to measure and
observe the blast wave.

The interesting thing about this was that this was an extension of what 
Enrico Fermi did at the "Trinity" shot.  What he did was, just before the 
test, he tore up a piece of paper into ~1in squares and lined them up 
perpendicular to the tower with a stick in the ground to mark the starting 
point.  The shock wave blew the bits of paper back (yes it was an otherwise 
very calm day with respect to ground winds) and from the average distance 
the bits were blown back, he was able to very accurately predict the yield 
of the bomb.  I think he was within 10% or less of the theoretical yield.  

Thanks for a little memory jog!

Scott Kniffin
Senior Engineer, Orbital Sciences Corporation
NASA Goddard Space Flight Center
Office of Systems Safety and Mission Assurance
Radiation Effects and Analysis Group, Code 562