[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.

[tedstryk]

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.

In the case that too many planets are found, It might be useful to retain a name like Kuiper belt, and teach that it contains lots of asteroids, comets, and planets. So there could be the Mercury - Neptune sequence, and then the "Objects of the Kuiper Belt."

[Guest_spaceffm_*]

For all interested in sizes i made 2 little Diagramms.
The First contains earth, some moons, biggest planetoids, some tno ect.

All sizes of all shown bodies are correct and in the same scale to each other as far as known.
Of course there it is not made public a definite diameter of 2003 UB313, 2005 FY9 und 2003 EL61 ( +b ).
2003 UB313 has a diameter of 2800km ( latest status ) in my graphic.
2005 FY9 has 1600km, 2003 EL61 has 1500 km with b aprx. 250km.

The 2nd graphic shows the first together with Jupiter...

Normal
used without credt so editid out,,, too bad

Before using it somewhere else please ask and give credit, i worked 6 hours in total time...Puh...thx



How small Enceladus is, but so activ...
So size does not always matter...