H/t to my mother
(I'm attempting a comment for the third time, apparently if I press the left arrow key to edit, your site navigates to your prior comment and deletes my comment! Garrrrh) I think Pluto's categorization requires a re-reconsideration. They downgraded it with the assumption that it was more a Kuiper belt object than a "real" planet. Now we've seen evidence of geologic activity! I thought Kuiper belt objects were dead ice cream scoops? Anyway, I'm holding a grudge on Pluto's behalf.
As I understand it, Pluto's geologic activity amounts to the surface and even atmosphere consolidating as the object drifts further and further from the Sun during its Autumn. It seems to have a "summer configuration" and a "winter configuration".
I'll experiment with the comments thing, to see if it's something I can fix.
If you want to build a ship, don't drum up people together to collect wood and don't assign them tasks and work, but rather teach them to long for the endless immensity of the sea.
--Antoine de Saint Exupery