30.

Luc Arnold notes that Type II Kardashev civilizations might build megastructures large enough to occlude the light from their star, producing visible shadows (like trigons or louvres), detectable as “writing” in the transitive light-curve from a luminary backdrop.⁴⁵ Tabetha Boyajian has observed that the star KIC 8462852 is, in fact, undergoing such a recurrent expanding occultation so titanic that no phenomenon in Nature can readily explain the light-curve of the ongoing dimming (which has persisted, dipping on one occasion by as much as 22%).⁴⁶ Even though a cometary envelope of dust might account for some of these observations, the oddness of the anomaly has, nevertheless, caused some astronomers to indulge in extravagant speculation, suggesting that a Dyson swarm of tiny bots might be engulfing the star so as to capture its entire output of energy.⁴⁷