Like in many areas of science, astronomy we humans come up pretty short when we try to generalize. To me there should be no controversy, just fun in learning more about nature. Philosophically, and quite relevant to this issue, is whether humankind, or a subset of humankind, is able to generalize successfully to understand the Universe or even "just" the Solar System.
(I enjoyed the poem posted very much, thanks Francis)
The question conveniently set up for debate when taken too seriously: Pluto is or isn't a planet, The topic is a convenient laboratory to learn about Pluto and the failure of humans to successfully generalize and compartmentalize everything neatly for consumption at the elementary schooling level. Pluto is what Pluto is, and for that matter Earth is what it is, and the concept of planet has no meaning other than conventions assigned. As a biologist, I am sure Nininger understood this well. The Solar system doesn't bend to elementary school definitions and more than to the definition of genus in biology. We all know a heck of a lot about Pluto, and we are pretty short when it comes to knowing what a planet is since defining a planet is not part of the requirement of having a Solar System.
So perhaps Jupiter is a star, and not a planet, it does radiate a lot more energy than it absorbs, doesn't it? The Jovians certainly would have a different perspective on whether Earth qualifies as a planet. We are just a little bigger than Ceres to them. Mars is pretty small and relatively devoid of atmosphere too... So the best we can do is learn about the Solar System and accept it for what it is, rather than dictate to the heavenly bodies what they are... So if one body rotates opposite to others, is inclined the "wrong" way on its axis, has an orbit out of wack or used to be a satellite, then so what. If Mercury were orbiting Jupiter it wouldn't be a "considered" a planet.
Pluto is a planet by convention, as is Jupiter. No two planets are alike. They are all just accidental matter floating around in our near space following the laws of the universe with no special need to conform to definition authorities.
I hope your daughter is able to consider this as well. You might remind her that the Earth is round because we say it is. But really it really is more elliptical and has an irregular surface. There is something to be learned about debating whether the Earth is round, but it is not whether it can be considered definitively a sphere or not. There is a fine line between understanding and preaching about the Solar System. Most of us cross it to make our points, but the Solar System continues to revolve and evolve independent of our conceptualization of each individual member of the Solar family.
Saludos
Doug Dawn
Mexico
En un mensaje con fecha 03/17/2004 9:42:53 AM Mexico Standard Time, [EMAIL PROTECTED] escribe:
Asunto: Re: [meteorite-list] Planet definition
Fecha: 03/17/2004 9:42:53 AM Mexico Standard Time
De: [EMAIL PROTECTED]
Para: [EMAIL PROTECTED], [EMAIL PROTECTED], [EMAIL PROTECTED]
Enviado por Internet
Hello List, I am a firm believer that Pluto is not a planet, I feel it is
to small and it's orbit is not like any of the other eight planets, so I
would have to say size is not the best way to define a planet but the shape
of it's orbit. : ) How many planets cross orbits of other planets?
Second thing, I have absolutely nothing to back this, it is just a
feeling, but I think Pluto and Charon were both Moons of a larger planet
that, in some big event, got sucked out on there own, and thats why they
float around together. Is this at all possible?
Thanks, Tom
peregrineflier <><
Proudest member of the YMCA # OU812
----- Original Message -----
From: Matson, Robert <[EMAIL PROTECTED]>
To: 'Rosemary Hackney' <[EMAIL PROTECTED]>;
<[EMAIL PROTECTED]>
Sent: Tuesday, March 16, 2004 10:03 PM
Subject: [meteorite-list] Planet definition
