In a vote that took place at the International Astronomical Union Conference on August 24th, 2006, Pluto lost its status as a planet in our solar system. Pluto was originally discovered in 1930 when scientists were searching for something that was interfering with Uranus's orbit. Though Pluto was estimated to be similar in size to Earth, it was later discovered that it was even smaller than our own moon, as well as many other moons. It is now known that there are thousands of planetary objects similar to Pluto, including Eris which is slightly larger than Pluto. Choosing to reclassify Pluto to a dwarf planet honors the fact that science is about making new discoveries. While it was a sad day for Pluto lovers, people in general have accepted the idea, and the next generation of children will grow up knowing only eight planets and thinking nothing of it. As Mike Brown, the astronomer who discovered Eris, noted following the IUC's decision, "science is self-correcting."

Transcript of lecture:

As you all likely know by now, Pluto has been officially demoted to a dwarf planet. What this means is that we will no longer include it as part of our solar system. The debate about whether or not Pluto should hold its status as a planet created such a conflict within the community of world astronomers that it has been called the Great Pluto War. The decision on whether or not to demote Pluto was put to a final vote by astronomers from around the world at the International Astronomical Union Conference. However, when I say from around the world, I don't mean worldwide. In fact, less than 10% of the world's astronomers voted, and most of those who were at the conference had already gone home by the last day when the vote took place. Of more than 10 000 potential voters, less than 500 took part, mainly because there was no way for them to cast their vote without actually being at the conference. Many astronomers believe that if electronic voting had been an option, Pluto along with two other celestial objects, would now be considered planets. Furthermore, the definition that was decided upon for a planet - that it must clear the neighborhood around its orbit - doesn't technically hold up, since Earth, Mars, Neptune, and Jupiter all have asteroids as neighbors.

The IUC decision disappointed many people outside the astronomy community too. You see, there are more than a few Pluto lovers out there. Some were so angry at the resolution that they began putting petitions together to have the ruling overturned. In New Mexico, where Pluto's discoverer was a resident, state officials have declared March 13th, Pluto Planet Day. Children in particular have a thing with Pluto and are perhaps the least willing to part with it. The name for the now dwarf planet was put to a vote in 1930. And incidentally, Pluto, which was chosen unanimously by a group at the observatory where it was discovered, had been submitted by a young schoolgirl.