Upgrade your account to a Community Supporter account and remove most of the site ads.
Rocket your D&D 5E and Level Up: Advanced 5E games into space! Alpha Star Magazine Is Launching... Right Now!

Reply to thread

Message: <blockquote data-quote="Umbran" data-source="post: 3025351" data-attributes="member: 177">There are many possible points to classification, and which one you're trying to serve can determine which distinctions you ought to be dealing with, essential or otherwise.  Historically, the term "planet" has had nothing to do with details of formation, or composition.  A term for "thing that orbits the sun that we can see reasonably easily" has served astronomers since the times of the Greeks, at least.  What we have here is merely a small refinement on that.   "Rocky world", "gas giant", "pluton", or "asteroid" as appropriate.  The terms for three of these thigns already existed, and the fourth is up for adoption now.  If you're aiming to make essential distinctions, then lumping gas giants and rocky worlds together is rather against your goal, as they are essentially different, in both composition and details of formation.Some would argue that Titan, and several other large moons, may have formed more like a planet than Luna.  And neither have much similarity to the origins of Phobos.  So, the term "moon" or "satellite" really has little to do with formation.  It's a matter of orbit, and that's about all.  We already have several examples of extrasolar planets that orbit with largish inclinations, so that's already falling through as a distinction.Mercury's eccentricity is nearly that of Pluto.  Most known extrasolar planets appear to have high eccentricities.  So I'd say goodbye to that criterion as well if I were you.That depends upon what you call "substantial".  Mars has only a wisp, less than that of the smaller, colder body of Titan.  I think Mars and Mercury long ago removed atmospheres from the general definition of "planet" in the eyes of the scientific community.Possibly, possibly not.  Since we don't know, we really shouldn't be talking about excluding it yet on this basis, now should we?It does - but it only deals with very basic discussion, which is reasonable for a very basic classification.  There are already terms for the finer distinctions, so there's no need to try to cram them into "planet".</blockquote>

Verification