Pluto, 1930 — 2006, RIP

While not necessarily a Canadian story I feel I must make some comments on the planet definition issue. After all, I was one of the IAU members in Prague who actually voted on the four resolutions on the definition of a planet and other Solar System bodies. There are a number of Canadian astronomers who work on Solar System bodies. The Canada France Ecliptic Plane Survey is undertaking a careful survey of Kuiper Belt Objects, of which Pluto is now recognized as the prototype.


The initial Resolution presented to IAU members was seriously flawed. There was wide agreement that something better was needed and this was voiced very vigorously in the Tuesday lunch hour discussion the last part of which is very interesting to watch. The original resolution totally ignored the dynamics of bodies in their definition. After all planets and all other Solar System objects do move!

Personally, I think after the disasterous initial proposal the process to reach the final four Resolutions was much too quick. The IAU should have tabled the issue until the next General Assembly in Rio de Janeiro and set up a more balanced Committee to go back to the drawing board.

I don't think we've heard the last of this and there is a petition of scientists who want to overturn the new IAU definition.

For everyone's information I voted YES, NO, YES, NO on Resolutions 5A, 5B, 6A, 6B.