Editing Rope trick effect (section)

==Sounding rockets==
[[File:fishbowlrockets.jpg|thumb|Array of [[sounding rocket]]s with instruments for making scientific measurements of high-altitude nuclear tests during liftoff preparations on Johnston Island]]
After a few milliseconds, the energy of the shock front will no longer be great enough to heat the air into [[incandescence]]. At that point, the shock front becomes invisible, a process known as "breakaway". This makes the shock wave difficult to diagnose beyond this boundary.

Photographs of nuclear tests often show numerous vertical rope-like lines to one side. These are typically created by small [[sounding rocket]]s launched a few seconds before the firing, leaving smoke trails. The purpose of these trails is to record the passing of the now invisible shock wave, which causes an obvious visual effect on the smoke by compressing the air into a [[lens (optics)|lens]]. This is not necessarily related to the rope trick effect in any physical way, but it is possible to confuse the two in some photographs. In the photograph of the [[Operation Tumbler–Snapper|Tumbler-Snapper]] test, the vertical lines in the lower-right corner are blast line poles, not smoke trails.<ref>{{Cite web|url=https://www.youtube.com/watch?v=g0r_4v2hA5c?t=1213|title = Operation Tumbler Snapper (1952)|website = [[YouTube]]| date=8 July 2009 }}</ref>