EPSS Colloquium spring-2018

Our understanding of the processes of planet formation have evolved considerably in the last 20 years as they have exposed that many planetary systems in our Galaxy do not look like our own. In particular, the inner and outer edges of our planetary disk come into focus and raise several interesting questions. Where was the outer edge of condensing solids in our outer Solar System? Our Kuiper Belt yields clues, but provides only unclear hints as to the answer. Why do we not have more massive planets close to our star, as many planetary systems do? I suggest that we may have in the past, and that Mercury is a collisional relic of an epoch where we had other planetary bodies interior to Venus.