Title: The role of Experimental Petrology to Support Space Mission Science: the Curious Behaviour of the Sun-skirting Rock-Comet Phaethon

Abstract: The near-Sun asteroid (3200) Phaethon, with both asteroid and comet-like features, presents a unique case for studying solar heating and small body properties. Despite its rocky composition and repeated close solar encounters (730°C), Phaethon remains active, emitting gas without significant dust release or surface renewal. To investigate this, we simulated solar heating on analogue materials (CM chondrite chips) representing Phaethon's surface. We found that while phyllosilicate, carbonate, and Na gas emissions play minor roles, the reversible decomposition of Fe-sulphides, coupled with low permeability, enables gradual gas release over multiple cycles. These findings offer a framework for interpreting DESTINY+ mission data and testing our predictions about Phaethon’s regolith and gas emissions.

Bio: Dr Martin D. Suttle is a Lecturer in Planetary Science at the Open University, within the School of Physical Sciences. He holds a PhD in Planetary Science from Imperial College London and previously worked as a research associate at the University of Pisa and the Natural History Museum (London). His current reasearch interests include: Aqueous alteration in primitive extraterrestrial materials ii) Developing fossilized micrometeorites as a new atmosphere and climate proxy; iii) The geological diversity of comets.

On-line: Segui il seminario on-line