The Dark Side of the Rings of Uranus

Science Express ^ | August 23, 2007 | Imke de Pater, H. B. Hammel, Mark R. Showalter, Marcos A. van Dam

[SunkenCiv]

The rings of Uranus are oriented edge-on to Earth in 2007 for the first time since their 1977 discovery. This provides a rare opportunity to observe their dark (unlit) side, where dense rings darken to near invisibility, but faint rings become much brighter. We present a ground-based infrared image of the unlit side of the rings that shows that the system has changed dramatically since previous views. A broad cloud of faint material permeates the system, but is not correlated with the well-known narrow rings or with the embedded dust belts imaged by Voyager. Although some differences can be explained by the unusual viewing angle, we conclude that the dust distribution within the system has changed significantly since the 1986 Voyager spacecraft encounter and occurs on much larger scales than has been seen in other planetary systems.

[SunkenCiv]

---

When Saturn's rings were discovered, early theoretical work proceeded on the assumption that an equilibrium was established between dust lost and dust gained. This implied that the ring's structure was essentially static. Later observations have showed that Saturn's rings are changing and these latest observations from Uranus make that a more general finding. More detailed models that don't make the equilibrium assumption also indicate that rings are dynamic structures that change on relatively short time scales... and these observations lend more support to these models... the only other edge-on pictures of Uranus' rings were taken by Voyager 2. In addition, most of the comparison data for gauging changes in the ring structures of both Saturn and Uranus use Voyager 2's pictures as their starting point. I don't think the people who conceived the Voyager probes ever imagined that Earth based telescopes would be able to obtain the sort of detail they are now obtaining. -- Chris Lee, Arstechnica

---

[SunkenCiv]

· join · view topics · view or post blog · bookmark · post new topic ·

[Monkey Face]

Awesome!

[dfwgator]

Must...resist....

[ladtx]

OK - I can't stand it!

Kkkkkk - heh-heh he said Uranus.

[SunkenCiv]

http://www.freerepublic.com/focus/f-news/1435997/posts?page=43#43

[SunkenCiv]

http://www.freerepublic.com/focus/f-chat/1545558/posts

[Monkey Face]

I promise, the title didn’t escape my notice! *snort*

I was trying to be a lady! *snicker*

[martin_fierro]

I was trying to be a lady!

Me, too.

I failed.

[Monkey Face]

I didn’t!

LOL!

[Billthedrill]

Well, dang it, with a title like that how does anyone expect us superannuated adolescents to resist?

Not me. Not this time. Must...resist...temptation...

[Brujo]

The rings of Uranus are oriented edge-on to Earth in 2007 for the first time since their 1977 discovery. This provides a rare opportunity to observe their dark (unlit) side ...

Not to be too dense, but if the rings are edge-on, how is either side visible?

[SunkenCiv]

rings around uranus site:freerepublic.com

Google

[SunkenCiv]

Hey, anything is possible on a gov’t grant. ;’) Sorry, I had to put that one in before the torches-and-pitchforks crowd gets in.

[TheRobb7]

"The Dark Side of the Rings of Uranus" You don't know the POWER of the Dark Side

[Oberon]

Luke...Turn your head and cough!

[AndrewC]

URANUS P.