Boyajian's Star, also called KIC 8462852, is a mysterious F type main sequence star around 1,280 light years away, which is of interest to scientists due to a long term dimming trend, as well as local dimming events.
The brightness of this star diminishes suddenly, and this phenomenon cannot be explained by our conventional astronomical knowledge. One such event occurred in May this year.
Several explanations could be proposed for what causes the dimming events. Some of these explanations include swallowing up a rogue planet by the star, a debris field consisting of colliding planets, and a cloud made of disintegrating comets. An interesting theory is that a Dyson sphere encircles the star, an alien megastructure that wraps around the entire star and harvests a significant part of its energy output.
However, a new study by NASA showed that there is no alien megastructure around the star, and the dimming is caused by an uneven ring of dust.
So, the dimming is caused by dust particles, but the origin of the dust is not yet determined. This star continues to be a focus of attention for astronomers.