Congratulations to Dan Spencer on winning the Guralp Prize, which is awarded to a second or third-year DPhil student for excellence in research. Dan’s research concerns the role of magmatism in transporting heat and chemistry in Io. In recent work recognized by the Prize committee, he has shown that magmatic segregation balances tidal dissipation in Io, and that magmatic emplacement at the base of the crust is a key control on crustal thickness. A well-deserved honour!