Talk:Ring system/Archive 1

Latest comment: 2 years ago by 24.18.17.104 in topic Question
Archive 1

Roche Limit

It is not true that material on the surface of moons orbiting within their fluid Roche limit will float off into the rings. This doesn't happen until the moon passes within its rigid Roche limit (in fact, it's effectively the definition of the rigid Roche limit). The Roche limit article doesn't mention any such moons... are there any? —Preceding unsigned comment added by 64.142.4.173 (talk) 09:15, 14 February 2009 (UTC)

Question

Is this purely a gas giant phenomenon? Or can rocky planets accrete a disk? — Jack · talk · 02:48, Monday, 9 April 2007

Yes they can. It is assumed the Earth had a ring system after the impact with Theia.

Yep, rocky planets can accumulate rings. In fact Mars is theorized to get a ring when Phobos crashes into it. (Also second commenter, I think you need to sign your username when you post. You just type four tildes {~ four times} ). 24.18.17.104 (talk) 16:21, 23 January 2022 (UTC)

Age?

Seems that the Saturnian system is now thought to be ancient, not ephemeral as stated in this article. kwami 12:13, 13 November 2007 (UTC)

Formation

This article does not mention the underlying physics behind ring formation. Why is a disk formed, and what is it aligned to?

This is one theory:

The rings are formed within the equatorial plane of the planet because the gravitational attraction is greater there, do to a bulge in the planet at its equator caused by the planet's rotation. Additionally, debris outside the ring will be robbed of its initial momentum and fall within this plane, due to collision with the material already within the plane.[1]

Source: http://saturn.jpl.nasa.gov/faq/saturn.cfm

GodGnipael February 19, 2008

This is a second theory:

Ring simulation experiment using fine-particle plasmas Yokota, T. Plasma Science, IEEE Transactions on Volume 29, Issue 2, Apr 2001 Page(s):279 - 282 Digital Object Identifier 10.1109/27.923708

We can create a ring structure around a magnetized miniature sphere which is immersed in a fine-particle plasma and rotated around its magnetic dipole axis. Aluminum fine particles generated by a boat method acquire charges by UV light irradiation and are converted to a fine-particle plasma. When the magnetized sphere was rotated in the fine-particle plasma, a ring appeared around the equatorial plane under certain conditions. Unipolar induction can reveal some of ring creation mechanisms of the ring; that is, the rotation frequency matches a theoretical simulating condition, and the location of the ring almost fits with the peak position of potential, which is two to three times the sphere radius. This experiment reveals one of mechanisms why the outer planets such as the Saturn, have rings. It indicates the fact that the unipolar induction plays an important role for the creation of the outer planets in the early stage of the solar system formation

http://ieeexplore.ieee.org/Xplore/login.jsp?url=/iel5/27/19971/00923708.pdf?arnumber=923708

They're proposing that the ice is Saturn's rings was a plasma?? kwami (talk) 19:40, 23 February 2008 (UTC)


I'll reiterate that the article needs more discussion of formation and of stability. It isn't at all obvious why they'd make such nice disks. After reading about the instability of Mars's inner moon, I wonder if some of the stability is due to tidal forces -- that something in geosynchronous orbit has no tidal forces, and as an extension, anything orbiting off of the equatorial plane (even at geosynchronous altitude) will experience a little tidal force... but that doesn't really explain a thin flat disk. —Ben FrantzDale (talk) 13:24, 11 June 2012 (UTC)

References

  1. ^ "Why do Saturn's rings all lie in the same plane? Why are planetary rings always found in their equatorial planes and not sometimes crossing their poles?". NASA's Jet Propulsion Laboratory (Frequently Asked Questions - Saturn).

Expansion

I think this article needs to be expanded. I expected a lengthy diatribe on the orbital mechanics of rings and how they remain stable. All I got was a page or two. Additionally, what about rings around moons? I found an article saying Rhea might have one: [1] Mathwhiz90601 (talk) 14:19, 7 March 2008 (UTC)

Rings of the Earth

Theres been much debate as of late of the earth's own rings, both natural and ideas for a man made outfit-

  • A ring around the earth during pleistocene [2]
  • Space Ring Could Shade Earth and Stop Global Warming[3]
  • Ring around the Earth? [4]
  • Would a saturn-like ring around the earth hold stable? [5]
The answer is "no" because Abdul Ahad said so [6] and they had the audacity to delete his page FIVE times. If you can prove that he isn't overturning a 400 year belief in western science, then I agree he should be excluded from WP for non-notable bio. —Preceding unsigned comment added by Kingkong77 (talkcontribs) 12:55, 2 October 2008 (UTC)

I thought we should add this if it made sense. Kingkong77 (talk) 14:39, 11 July 2008 (UTC)

Compare with asteroid belt?

In this article is it worth comparing and contrasting planetary rings with the asteroid belt, Kuiper belt and other Circumstellar disks - or even with galactic disks? Are these all basically equivalent structures on different scales? —Preceding unsigned comment added by 82.71.43.37 (talk) 16:33, 13 March 2010 (UTC)