Talk:Oort cloud/Archive 1

message: "The most widely-accepted theory of its formation is that the Oort cloud's objects initially formed much closer to the Sun as part of the same process that formed the planets and asteroids, but that gravitational interaction with young gas giants such as Jupiter ejected them into extremely long parabolic orbits. This process also served to scatter the objects out of the ecliptic plane, explaining the cloud's spherical distribution. While on the distant outer regions of these orbits, gravitational interaction with nearby stars further modified their orbits to make them more circular."
I think something is being confused here.  Is this perhaps talking about the inner oort cloud?  Do you have a link? Anthony DiPierro 14:33, 17 Mar 2004 (UTC)
replies: text: I first read it at http://www.gps.caltech.edu/~mbrown/sedna/ under the section "What is the Oort cloud and what is its relationship to Sedna?": "Early in the history of the solar system many many small icy bodies were orbiting the sun and getting sling-shot out by close encounters with planets. As they were travelling further and further from the sun, the orbits of these bodies were affected by distant stars, causing them to slow down and stay attached to the sun. Sedna probably suffered a similar fate, except the stars which affected it must have been much much closer than previously expected. We believe that this is evidence that the sun formed in a tight-knit group along with many other stars." Bryan 15:39, 17 Mar 2004 (UTC)
replies: text: OK.  This looks good as at least "a theory".  I'll restore it as was and look into some other links.  Thanks. Anthony DiPierro 15:55, 17 Mar 2004 (UTC)
thread_title: Oort cloud formation

message: gravitational interaction with young gas giants such as Jupiter ejected them into extremely long elliptical or parabolic orbits...  While on the distant outer regions of these orbits, gravitational interaction with nearby stars further modified their orbits to make them more circular.
The recent addition of "elliptical" orbits make me wonder.  I think the term "nearly parabolic" might be better in this context, since no real orbit is exactly parabolic.  But calling an orbit way far out an "ellipse" seems wrong since if it is that far out it is affected enough by nearby stars that it is really an n-body orbit that isn't even conic.  Similarly, when objects are ejected in strongly hyperbolic orbits I'm guessing that the nearby stars can't stop it and it cruses on like voyager I and II.  Of course, checking references would be the best approach, but I suspect that the word eliptical is inappropriate here.  I suspect that applies to the inner oort cloud described later on also, but the case for "elliptical" may be a bit stronger there NealMcB 00:42, 2004 May 16 (UTC)
:As the one who added elliptical, I think "nearly parabolic" is indeed probably better. That includes both highly elongated elliptical orbits (at least in terms of simplistic orbital element analysis, discounting the n-body caveat you mention) and not-very-extreme hyperbolic ones, both of which I imagine would be common for this process. Bryan 00:56, 16 May 2004 (UTC)
thread_title: Elliptical orbits?

message: I read in this astronomy textbook for young earth creationist home-schoolers about how scientists have invented the Oort cloud to explain away the existence of these comets, which should have been vaporized long ago (if the universe/solar system is actually more than several thousand years old!), and I at first thought it was just some fundamentalist BS. But here I find Oort cloud on Wikipedia, and it turns out they were right! Well, at least in that there's no evidence for an Oort cloud, and that these comets shouldn't still be flying around after billions of years. Just thought it was kind of funny. Tix 20:44, 14 July 2005 (UTC)
replies: text: I have one such (junior high level?) science textbook I found at a swap shop, I bring it out at Halloween to scare friends who never knew such horrors existed.  Seriously.  Reading the book's passages over the phone has actually prompted at least two people to claim I was making them up. human 03:46, 1 February 2007 (UTC)

text: Perhaps befor putting forward statments arguing with the artical you should read the sorces and sitations in full. The artical is not a point of fact to argue over. The theory itself is. Wikipida is full of articals giving a bit of infomation on a theory without the evidence (which is VERY dry and boring). —The preceding unsigned comment was added by 62.232.65.170 (talk) 09:11, 5 January 2007 (UTC)
thread_title:  Young earth? 

message: For every article on mainstream science you can find opposing opinions or those outside the mainstream. Walt Brown's creationist ideas fall into this category. That his ideas have the occasional supporter like our friend User:Barwick means that the encyclopedia can have a place for them. The place that the encyclopedia has is a place called Walt Brown. That is, if User:Barwick wants to put in documented descriptions of Brown's ideas about the Oort cloud, the appropriate place to do it is in the article about the person who is pushing the idea. It isn't appropriate to include every "skeptic" or "outside the mainstream" view in a mainstream article becacuse notability with respect to the article is important. I imagine Gene Ray would have a thing or two to say about the existence of the Oort Cloud. This does not mean his ramblings on the subject should be reported on this page. Rather, keep the against the mainstream folks to their own articles. This should settle the matter. Joshuaschroeder 06:17, 11 November 2005 (UTC)
thread_title: Notability and science articles

message: I am pretty sure, that the original statistical analysis by Oort shows clear evidence that most known comets come from two source in the solar system: The Kuiper belt (short periods, within the ecliptic) and the space we now call Oort cloud (long period, random orientation). I think it is bad POV to describe only that this second source is pure speculation to plug a supposed "hole" in current scientific understanding of the evolution of the solar system!  See this overview, for example. Awolf002 20:46, 30 November 2005 (UTC)
thread_title:  Statistical evidence 

message: Should there be something in this article about the Hills cloud and its relation to the Oort Cloud? -- Eroica 14:07, 26 November 2006 (UTC)
replies: text: How widely supported is it in the scientific community? I just put together a stub on the subject since I had no idea what it was at first and I worked from just one source so I don't know whether it's fringe or not. Bryan 19:14, 26 November 2006 (UTC)
thread_title:  [[Hills cloud]] 

message: The table in the section looks too much like original research. Please provide a paper (not just a Sedna press release) that names the listed objects as potential Oort Cloud objects.--JyriL talk 20:16, 26 December 2006 (UTC)
thread_title: Oort Cloud objects