I would write about this even if it were not significant, just because noctilucent or "night-shining" is such a gorgeous word.
Looking (as I often am these days) for places or objects that satisfy the somewhat loose set of criteria I have established for my space heritage list. I currently have graduate students working on Nigeria, and places registered on national heritage lists, but this still leaves much for me to do.
Sweden is as yet unrepresented, and I discovered the existence of the Kronogard launch site, near Kabdalis in the far north. The Stockholm Institute of Meteorology, with assistance from NASA and the US Air Force, launched Nike-Cajuns from 1962 to conduct upper atmosphere experiments by releasing large quantities of talcum powder at altitude - artificial "noctilucent" clouds - and studying the effects. Experiments of this kind were also very common at Woomera, but my impression was that they were done during the daytime rather than night.