[X] My Assistant

[SFJCody]

http://groups.yahoo.com/group/mpml/message/15111

[Guest_BruceMoomaw_*]

In our little private "Planetary Sciences" webgroup, Ron Baalke quoted Mike Brown himself as saying yesterday: "Based on Spitzer measurements, 2005 FY9 is confirmed to be smaller than Pluto." Unfortunately, he didn't say how much smaller. But at any rate the Revolution is now upon us: depending upon what size you use as a dividing line, the Solar System no longer has 9 known planets. It now has 10 or 11, or else it has 8, or else (if you follow Alan Stern's lead) it has a hell of a lot more. What we are really going to have to tell the schoolkids, of course, is that the question from now on will be forever ambiguous.

[JRehling]

In our little private "Planetary Sciences" webgroup, Ron Baalke quoted Mike Brown himself as saying yesterday: "Based on Spitzer measurements, 2005 FY9 is confirmed to be smaller than Pluto." Unfortunately, he didn't say how much smaller.  But at any rate the Revolution is now upon us: depending upon what size you use as a dividing line, the Solar System no longer has 9 known planets.  It now has 10 or 11, or else it has 8, or else (if you follow Alan Stern's lead) it has a hell of a lot more.  What we are really going to have to tell the schoolkids, of course, is that the question from now on will be forever ambiguous.

If I were designing a roster of solar system entities for fifth grade classrooms for the 2006-7 school year, I would have it read something like this:
Sun, Mercury, Venus, Earth, Mars, asteroids, Jupiter, Saturn, Uranus, Neptune, Pluto, [Whatever name 2003 UB313 ends up getting], comets, Kuiper Belt. (Yes that list ends up sounding like the roster of Santa's reindeers, which might be a nice way to get kids to remember some of it.)

If the number of things of planetlike size gets to be much bigger, it will start to be cruel to expect wee little kids to remember them all, which may merit dropping individual mention of everything past Neptune -- that's not a scientific measure, but a pedagogical one.