Oh Pluto!

It's official: the International Astronomical Union has voted in Prague to demote Pluto to a lesser rank of "dwarf planet". The remaining eight will be officially "planets", or "classical planets" according to some media reports.

Here is the result.

To me that's a tad pity since I am so used to the idea of Pluto as a planet. Although I knew about its out of wack musical - chairs - with - Neptune orbit even as a kid. However, I support the IAU decision to make the definition of a planet more systematic. It's not consistent to leave Pluto as a planet while similar sized bodies like Ceres and UB313 get left out.

In addition, if every Pluto-sized body becomes a new planet, then kids in school may have to learn a ton of names (53 and increasing!) which would so totally kill any tinsy bit of interest they might have in astronomy.

Still, dwarf planet or whatever, that doesn't diminish my fascination with Pluto. I am still following the New Horizons mission closely. Earlier this year astronomers using the Hubble Space Telescope discovered two additional moons orbiting Pluto, bringing the total number to three.

















Pluto hasn't given up all of its secrets yet, so be prepared to be surprised when New Horizons arrives. It is likely to uncover a treasure trove of scientific data.

I often say to younglings "I'm so old that when I was a kid, there was a West Germany and a East Germany."

Now I can add "When I was a kid, Pluto was a planet!"