It sounds from the article like this is something that happened frequently in the 1950s? Has it been observed since?
If not, the “radioactive dust” hypothesis seems to make a lot of sense.
Yeah, even by the article's own admittance this seems like a nothingburger.
Pandora's Star, a trilogy by Peter F. Hamilton describes a situation where two stars suddenly turn off and humans goes investigating. My favourite character is Paula Myo.
Cross-eyed the picture i can say there is more than 3 just spots.