A cosmic identity crisis: [from the Arizona Republic, editorials, Monday, 21 August 2006]

“One little number is about to change, and it’s a mental earthquake. The solar system has 12 planets, not nine… The ninth planet is dear to Arizonans; after all, it was discovered at Lowell Observatory in Flagstaff… Is Pluto a planet? To decide, the [International] Astronomical Union had to come up with a definition of “planet.”… To complicate the picture, there would be a new subcategory called “plutons,” Pluto-like planets that take at least 200 years to orbit the sun. (And to complicate the process, geologists are objecting to the word pluton, which they already use for some rock fomations). Yikes! Of course, the solar system hasn’t gotten more convoluted. Scientists are just starting to discover its amazing complexity, including the icy objects of the Kuiper Belt…

[Stay tuned; the IAU is debating this, intensely, this week, in Prague. So, despite what you may have read, this is still very much, to be determined…]

Arizona Republic