Pluto

Most of us were told in school that the sun has nine planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto. What our science teachers didn't tell us was that astronomers debated among themselves whether Pluto was really a planet.

Now Pluto is considered to be a Kuiper Belt object. But whether it's a plant depends on what the definition of "planet" is. It seems astronomers don't have a formal definition of the word. This week, a group of astronomers is meeting in Prague, and the agenda includes a debate of the definition of "planet."

Some astronomers want to kick Pluto out of the club and say the solar system has eight planets. Others want to define "planet" in such a way that we could end up with as many as 53 known planets, based on recent discoveries at the farthest reaaches of the known solar system.

What does that have to do with the price of beer at Ribfest? It means science teachers in our local schools had better be careful what they teach our kids about the solar system. If the teachers aren't up to date on their science, they could find themselves knowing less about the subject that some of their students. And it means the school boards in the region had better review the astronomy sections of any textbooks in use or being considered for use.