Modern and ancient micrometeorites: Experimental and numerical studies

Micrometeorites are sub-millimetric extraterrestrial samples, which dominate the flux of extraterrestrial matter entering the Earth atmosphere. Every micrometeorite is altered by the interaction with the atmosphere. However, they can be found embedded in larger meteorites, in which case they are called microxenoliths. Microxenoliths are ancient micrometeorites, and they allow the study of past epochs of the Solar System, not accessible by studying micrometeorites. New microxenoliths have been discovered and studied in H chondrites and in the carbonaceous chondrite Isheyevo. Many different techniques (scanning and transmission electron microscopy, Raman spectroscopy, mass spectrometry) have been applied to characterize them. Also, numerical simulations have been performed to investigate their origin and the effects they suffer during the passage through the Earth atmosphere.