There seems to be some indecision as to whether a planet can be defined solely by size, or distance from the sun & orbital inclination with respect to the ecliptic. The cosmos- and the solar system- is a big place- what would a hypothetical body be called with an orbit longer than 200 years, yet earth-sized or larger? And if it's orbital plane coincided with the ecliptic? Also, none of this seems to address classifying extra-solar planets. As more planetary systems are discovered among other stars, the solar system apparently becomes more and more unique. Will every system have it's own classification system? While not currently practical, it would be nice to see at least medium-resolution images of some of these bodies before pigeonholing them, especially Ceres. Humans have this need to make lists. I suppose it's out of the question to teach our youth that the solar system is composed of the sun, and many other smaller, non-fusing bodies of various sizes orbiting at various distances- a list that will change as discoveries are made. --- Patrick Wiggins <paw@wirelessbeehive.com> wrote:
This will be in the next issue of News but since that wont be out for a couple of days I figured I post it here first.
Patrick
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