From Wikipedia: Rope trick is the term given by physicist John Malik to the curious lines and spikes which emanate from the fireball of certain nuclear explosions just after detonation.
Amazing photo shows this effect. Those damned nuclear explosions look pretty much interesting… Something magical can be found in this forms in space, but after seconds destruction is obvious so Earth experiments are very bad.
More about Rapatronic Camera, that recorded this photo can be found on simplethinking.com
check out previous post about Atomic Explosion Photos