Experts meet to decide Pluto fate, Finally we'll know what a 'planet' is... |
Experts meet to decide Pluto fate, Finally we'll know what a 'planet' is... |
Aug 14 2006, 06:06 AM
Post
#1
|
|
Member Group: Members Posts: 295 Joined: 2-March 04 From: Central California Member No.: 45 |
-------------------- Eric P / MizarKey
|
|
|
Aug 15 2006, 04:36 PM
Post
#2
|
|
Senior Member Group: Moderator Posts: 3241 Joined: 11-February 04 From: Tucson, AZ Member No.: 23 |
QUOTE I must say that I disagree. As reductionists, it is our job to categorize. Finding a workable definition for a planet has only become necessary, and painful, because we have made so many fundamental discoveries in our solar system and others since 1992 (the year the first KBO and the first pulsar planets were detected). It's not about culture. It's about good science. But we also shouldn't present the solar system as a neat and tidy place when it isn't. The discoveries since 1992 have allowed us to appreciate the complexity of not just our solar system, but other solar systems as well. From other solar systems, we have found large planets that don't following neat and tidy orbits, some have high eccentricities for example. We have found stars with two accretion disks at different inclinations. In our own solar system, we have found icy dwarf bodies that follow a miriad of orbits and have various shapes, and there maybe some the approach the size of the terrestrial planets. The solar system (and other systems) are not neat and tidy places and we shouldn't pretend that it is. Listen, I understand we need a system for categorization. It allows us to more easily make sense of our world or the worlds around us. I understand that. But the amount of press this has gotten and the amount of breath and time spent on this is not worth it. Pluto is still Pluto whether it is a planet or a TNO, or any icy dwarf, or a dog. Setting arbitrary definitions also makes the word less useful for scientific purposes. A TNO at 4000 km probably didn't form fundimentally any different from a 2000 km wide body (or a 1900 km wide body). As long as we make it clear to the public what the words value is (for classification purposes and for nomenclature purposes), I think we can come to an understanding. But if we treat it as if objects that are planets are some exclusive group or club and those that are just moons or minor planets are inferior and aren't worth our time in terms of exploration purposes (just because they are not planets), then we have a problem. Okay, I'm sorry about the rant... -------------------- &@^^!% Jim! I'm a geologist, not a physicist!
The Gish Bar Times - A Blog all about Jupiter's Moon Io |
|
|
Guest_AlexBlackwell_* |
Aug 15 2006, 04:45 PM
Post
#3
|
Guests |
But we also shouldn't present the solar system as a neat and tidy place when it isn't. The discoveries since 1992 have allowed us to appreciate the complexity of not just our solar system, but other solar systems as well. Jason, I think you and everyone else are missing Alan's point. No one is trying to obscure the fact that our "solar system [isn't] a neat and tidy place." Quite the contrary. Taxonomies and classification systems are very useful in science, especially in astronomy. Discerning hierarchical relationships, ipso facto, can lead to scientific discoveries. |
|
|
Aug 15 2006, 05:01 PM
Post
#4
|
|
Member Group: Members Posts: 809 Joined: 11-March 04 Member No.: 56 |
No one is trying to obscure the fact that our "solar system [isn't] a neat and tidy place." Quite the contrary. Taxonomies and classification systems are very useful in science, especially in astronomy. Discerning hierarchical relationships, ipso facto, can lead to scientific discoveries. I don't disagree; but if it were the business of the IAU to try to make its nomenclatorial system conform to any one of several possible planetary taxonomies, surely the first order of that business would be to find a way of pointing out that Jupiter and Mercury are not the same kind of object? |
|
|
Aug 15 2006, 05:36 PM
Post
#5
|
|
Member Group: Members Posts: 532 Joined: 19-February 05 Member No.: 173 |
I don't disagree; but if it were the business of the IAU to try to make its nomenclatorial system conform to any one of several possible planetary taxonomies, surely the first order of that business would be to find a way of pointing out that Jupiter and Mercury are not the same kind of object? Perhaps these will help some who have not seen them; sorry for spamming those who did-- the links will save me from typing my views: Gravity Rules: http://www.spacedaily.com/news/outerplanets-04b.html Copernicus Smiled: http://www.thespacereview.com/article/450/1 |
|
|
Aug 15 2006, 05:58 PM
Post
#6
|
|
Member Group: Members Posts: 809 Joined: 11-March 04 Member No.: 56 |
Perhaps these will help some who have not seen them; sorry for spamming those who did-- the links will save me from typing my views: Gravity Rules: I'm quite fond of the "rounded by gravity" criterion myself; but the presence of objects like 2003 EL61 and Iapetus makes it rather difficult to apply. Objects with diameters between 400km and 1600km exhibit a wide variety of shapes: spheres, near-spheres, flattened spheroids, spindly spheroids, nicely rounded ellipsoids, bumpy, lumpy, and partially concave ellipsoids, and plain old irregulars. If there's a direct correlation between shape and size or mass, it's not an obvious one. Why wouldn't a cutoff above 1600km diameter be just as defensible a gravity-based division as one below 400km? |
|
|
Lo-Fi Version | Time is now: 20th September 2024 - 08:42 PM |
RULES AND GUIDELINES Please read the Forum Rules and Guidelines before posting. IMAGE COPYRIGHT |
OPINIONS AND MODERATION Opinions expressed on UnmannedSpaceflight.com are those of the individual posters and do not necessarily reflect the opinions of UnmannedSpaceflight.com or The Planetary Society. The all-volunteer UnmannedSpaceflight.com moderation team is wholly independent of The Planetary Society. The Planetary Society has no influence over decisions made by the UnmannedSpaceflight.com moderators. |
SUPPORT THE FORUM Unmannedspaceflight.com is funded by the Planetary Society. Please consider supporting our work and many other projects by donating to the Society or becoming a member. |