Here we want to use the recovered volcaniclastic sediments to shed light on ongoing debates of potential asteroid impact sites in the eastern Mediterranean. At several sites, the recovered layers contained µm-sized micro-spheres as well as cm-sized, banded glass droplets.

The microspheres were found within the caldera of Santorini in layers that were deposited following the cataclysmic Minoan Eruption ∼1600 BCE. In 2021 a, by-now retracted, study proposed that the Bronze Age city of Tall al-Hammam, located in modern-day Jordan, might have been destroyed by an airburst during the same period as the Minoan Eruption. Located about 1000 km to the NW of Tall al-Hammam, the deposits of Santorini could conceivably contain material formed by a significantly sized airburst in Jordan. Thus, the presence of micro-spheres would be an intriguing indicator supporting the airburst theory. However, so far none of our analyses point toward an impact as the origin of the spheres. A more likely explanation for the occurrence of these micro-spheres at Santorini is their formation through heat generated by volcanic lightning in the ash column during the eruption.