Student Colloquium, Emma Kirstine Holden Thorsøe: The Discovery and Demotion of Pluto
Supervisor: Simon Albrecht
In this presentation, I will go through the historical aspects of Pluto’s discovery, and the following discoveries,
that ultimately resulted in Pluto being ’demoted’ to the status of dwarf planet. Reducing the number of planets
from nine to eight.
To do this I will start by discussing what a planet actually is, taking us back to the time, where we had a
geocentric view of our universe. From here I will take us through a chronological timeline of discovering our
own Solar System, all the way up to and including the discovery of Eris and other larger Kuiper Belt objects.
Afterwards I will discuss the definition of a planet agreed upon in 2006. What is it? What does this mean for
Pluto? And do the new rules even make sense?
Finally I will look outwards, both from the Solar System, and discuss the exoplanets that we now discover, and also in time, and what we can expect to see in the future. Both in our own Solar System and beyond.