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Saturn's A-ring Soaks Up Debris Ejected from Nearby Moon

Soulskill posted more than 6 years ago | from the yes-it-is-a-moon dept.

Space 64

ScienceDaily is running a story about the recently discovered interaction between Saturn's A-ring and one of Saturn's small moons, Enceladus. Thanks to data from Cassini, scientists have discovered that ejected matter from Enceladus' ice geysers is absorbed into the A-ring, where it is then trapped. We discussed the geysers themselves a few years ago, and researchers have been working since then to determine where the material was going. Quoting: "This is the latest surprising phenomenon associated with the ice geysers of Enceladus to be discovered or confirmed by Cassini scientists. Earlier, the geysers were found to be responsible for the content of the E-ring. Next, the whole magnetic environment of Saturn was found to be weighed down by the material spewing from Enceladus, which becomes plasma -- a gas of electrically charged particles. Now, Cassini scientists confirm that the plasma, which creates a donut-shaped cloud around Saturn, is being snatched by Saturn's A-ring, which acts like a giant sponge where the plasma is absorbed."

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Cosmos reference: (2, Insightful)

G4from128k (686170) | more than 6 years ago | (#22457794)

With all that plasma, the A-ring looks like great habitat for superconducting electrovores.

Re:Cosmos reference: (1)

Brian Gordon (987471) | more than 6 years ago | (#22458104)

plasma -- a gas of electrically charged particles
I'm no physiscist but I'm pretty sure it's a distinct phase..

Re:Cosmos reference: (0)

Anonymous Coward | more than 6 years ago | (#22458214)

More like cosmic bukkaki. The ultimate in galactic porn, ironically, comes from NASA...

Re:Cosmos reference: (0)

Anonymous Coward | more than 6 years ago | (#22459304)

It's spelled bukkake you insensitive clod. And it isn't intergalactic porn, it doesn't even come close to interstellar. It's more like lunatic porn.

A-Ring? (-1, Offtopic)

Anonymous Coward | more than 6 years ago | (#22457818)

I guess this would explain the "I'll shove a moon up your ass" expression.

Oh lord (-1, Offtopic)

soulsteal (104635) | more than 6 years ago | (#22457826)

Let the goatse jokes..... BEGIN!

Re:Oh lord (-1, Offtopic)

Anonymous Coward | more than 6 years ago | (#22458004)

This is Saturn, not Uranus. /oblig

Re:Oh lord (1)

DiscipleN2k (914143) | more than 6 years ago | (#22467536)

Nearly every post above this has been modded down? Clearly someone doesn't appreciate the fine art of potty humor.

pr0n? (0, Offtopic)

slserpent (898476) | more than 6 years ago | (#22457872)

Enceladus is ejecting matter from its geyser into Saturn's A-ring?

This sounds like pr0n to me.

Same problem (5, Funny)

jettoblack (683831) | more than 6 years ago | (#22457900)

I often have the same problem with Enchiladas and my A-ring.

Re:Same problem (1)

Thecarpe (697076) | more than 6 years ago | (#22473884)

Never not funny...I was expecting it, I read it, and giggled like an 8-year-old...who's serving up the Uranus joke?!

Moons creating moons? (2)

mrxak (727974) | more than 6 years ago | (#22457928)

I know one of the theories for moon formation is debris in orbit of a planet slowly forming into larger bodies until eventually there's a new moon. Could this be a case where one moon is "leaking", and the eventual result will be a new moon formed out of Saturn's rings?

Re:Moons creating moons? (2, Insightful)

Jugalator (259273) | more than 6 years ago | (#22457970)

I don't think that can happen with Saturn's gravity tearing things up and putting things in orbit until they can form a larger body?

And if it could, I'd think it should have happened many million years ago already?

Re:Moons creating moons? (2, Interesting)

mrxak (727974) | more than 6 years ago | (#22457994)

No doubt new comets or other objects are going by and getting ripped apart all the time to add to Saturn's rings, but Saturn has a lot of moons already, so clearly Saturn is getting moons somehow.

Re:Moons creating moons? (5, Informative)

CheshireCatCO (185193) | more than 6 years ago | (#22458084)

To put it more exactly, tidal forces will tear apart anything within, roughly, the A ring. (Cavaets: this applies to bodies with no internal cohesion and cases where there's a large size differential move the limit inward, a la Porco et al. 2006.)

Re:Moons creating moons? (2)

mrxak (727974) | more than 6 years ago | (#22459192)

Okay, that makes sense. Still, enough stuff gets built up in the rings, broken apart or otherwise, and collisions will probably be more frequent. Where there's collisions, there could be things breaking out to a higher orbit where such moons could actually coalesce.

Re:Moons creating moons? (3, Informative)

CheshireCatCO (185193) | more than 6 years ago | (#22462322)

You don't need collisions for such viscous spreading (and most stuff wants to move inward anyway). Also, the A ring is somewhat held in check by the larger moons, so spreading is very slow.

Re:Moons creating moons? (1)

StikyPad (445176) | more than 6 years ago | (#22469178)

tidal forces will tear apart anything within, roughly, the A ring.

So you're saying that putting something inside the A ring would likely a hole tear?

Re:Moons creating moons? (1)

Jugalator (259273) | more than 6 years ago | (#22464136)

but Saturn has a lot of moons already, so clearly Saturn is getting moons somehow.
Yeah, by capturing objects, like most other planets are theorized to have done.

Re:Moons creating moons? (1)

CheshireCatCO (185193) | more than 6 years ago | (#22466004)

Saturn's outer, irregular moons are likely captured. However, the only medium or large moon in the solar system that I know of which is thought to be captured is Neptune's Triton. Most medium to large moons are believed to have formed in situ, as well as a fair number of the smaller guys. The fact that most of the inner and/or large moons have co-planar, low-eccentricity orbits is very suggestive of co-formation. This includes Saturn's moons nearest the rings.

Re:Moons creating moons? (-1, Redundant)

Anonymous Coward | more than 6 years ago | (#22458038)

I hate it when debris is ejected from a moon. Who'd have thought it would have been absorbed by the A-ring. Does the same phenomenon occur with Uranus?

Re:Moons creating moons? (-1, Redundant)

Anonymous Coward | more than 6 years ago | (#22458394)

Well a lot of stuff is ejected from my anus, but none of it has created a moon so far as I know.

Re:Moons creating moons? (5, Informative)

CheshireCatCO (185193) | more than 6 years ago | (#22458114)

Tides are a big problem for forming a moon within, roughly, the A ring. A bigger problem is that Enceladus produces "dust" (very small particles, the size of particles in cigarette smoke, approximately), albeit made mostly of ice. It takes a long time to form this stuff into macroscopic bodies when the conditions are friendly (which they aren't). Worse still, Enceladus isn't really putting out that much mass per time. It'd take a very long time to put out enough to make another decent-sized moon, even at 100% efficiency.

Re:Moons creating moons? (5, Informative)

TripMaster Monkey (862126) | more than 6 years ago | (#22458140)

The debris being generated cannot form into a new moon, as the A-ring is within the Roche radius [wikipedia.org] of Saturn.

Re:Moons creating moons? (3, Interesting)

Speare (84249) | more than 6 years ago | (#22462890)

IANAAP, and I'm not disagreeing with the basic point of what you are saying, but...

from the link you provided, the radius of the Roche limit (1) depends on the structural integrity of the satellite, not just a constant radius from the stronger body, and thus (2) does not apply at all to the pulverized bits of the weaker body.

The Saturn A ring therefore decorates a particular Roche limit that applied to some other body that was pulverized in the past, and not a guaranteed "point of no moons" around Saturn. If the Roche limit were not based on the structural integrity of the moon, then even the broken boulders of an ex-moon would be further pulverized into rocks, then sand, and finally nano-dust. If a boulder survives inside the original body's Roche limit, it must be because it has a new Roche limit that is closer to Saturn.

While I admit that the pulverized bits are unlikely to coalesce into a moon, I wouldn't say they're impossible. If something were to cause a strong self-attractive force, say, some ionizing comet or who knows, the FSM's noodly appendages, a moon that developed into a highly rigid structure could continue to survive there. If we someday mine asteroids in the region, structural integrity of manmade or man-inhabited objects will obviously be of prime importance.

Re:Moons creating moons? (2, Informative)

CheshireCatCO (185193) | more than 6 years ago | (#22466146)

The Roche limit, as usually defined, is for a body with *no* internal strength. This is a very reasonable limit to use as anything trying to accrete from small particles would not have internal strength (between these particles) immediately. It's difficult to invoke any kind of strong enough force to overcome the tidal stretching: electrostatic charges, for example, are too small to work on macroscopic bodies --- large charges don't persist for long as they attract opposite charges quickly and cancel out. (Besides, as soon as two opposite-charged ring particles meet, I suspect that they'd exchange charges faster than you can sinter the particles together. Once the charges are equalized, there's no more force to hold them together.) The only way of triggering growth in the main rings that I know of is to seed the growth with larger cores which are dense enough to attract the smaller ring particles and hold on to them for long enough for the ices to bond together. Of course, this process is self-limiting. (http://science.slashdot.org/article.pl?sid=07/12/07/1326240)

On the other hand, bodies *with* internal strength have a very different tidal limit. If the strength is similar to what we are used to on Earth, then there's no real reason to worry about Saturn right down to the planet's "surface". (Consider Earth: we're well inside the Roche limit, but satellites (and astronauts!) don't fall apart.)

Re:Moons creating moons? (3, Informative)

techno-vampire (666512) | more than 6 years ago | (#22458414)

No. With the exception of the E ring, all of Saturn's rings are within its Roche Limit. [wikipedia.org] Tidal forces would prevent a new moon from forming that close just as they'd break up an existing one.

Re:Moons creating moons? (1)

CheshireCatCO (185193) | more than 6 years ago | (#22467226)

Actually, the G ring is exterior to the E ring. The F ring's status is questionable in this respect (it depends on your assumptions). Even the outer A ring might be outside the Roche limit, depending on what physics you think is occurring.

Also, existing satellites don't break up inside to the Roche limit. Pan and Daphnis are most likely within this limit, yet persist. Atlas, Prometheus, Pandora, and maybe even Janus and Epimetheus are potentially inside the Roche limit, depending on your choice of assumptions.

Re:Moons creating moons? (1)

techno-vampire (666512) | more than 6 years ago | (#22467686)

OTOH, the breakup isn't exactly instant; it takes time. Who knows how long those moons have been that close or how close they might (or might not, of course) be to breaking up?

Re:Moons creating moons? (1)

CheshireCatCO (185193) | more than 6 years ago | (#22468150)

How long do you think it takes? Tidal breakup ought to occur on a timescale of orbits, meaning a few days. These bodies have persisted for at least decades and there is evidence that they formed with the rings which are at millions, if not billions, of years old. It sounds like you're grasping at straws to support an invalid claim. There are moons inside the Roche limit because they *can* exist there thanks to internal strength (a factor neglected in the Roche calculations). It's just *forming* moons there that's difficult.

Re:Moons creating moons? (1)

techno-vampire (666512) | more than 6 years ago | (#22468352)

How long do you think it takes? Tidal breakup ought to occur on a timescale of orbits, meaning a few days


I don't know, I'm not a physicist. I'd expect it to depend on a number of factors, such as tensile strength, size of the body, size of the primary and how far inside the limit it is. Of course, as a layman ICBW. That's why I made sure to point out that they might or might not break up.

testing (-1, Offtopic)

Anonymous Coward | more than 6 years ago | (#22457954)

(hello(

Go to Radio Shack (2, Funny)

Anonymous Coward | more than 6 years ago | (#22457960)

"the whole magnetic environment of Saturn was found to be weighed down by the material spewing from Enceladus, which becomes plasma -- a gas of electrically charged particles. Now, Cassini scientists confirm that the plasma, which creates a donut-shaped cloud around Saturn, is being snatched by Saturn's A-ring"

Yeah, that used to happen to me back when I listened to cassettes, too. A decent degausser will fix it.

Hey! (0, Redundant)

Digitus1337 (671442) | more than 6 years ago | (#22458030)

That's no moon!

Re:Hey! (4, Funny)

CheshireCatCO (185193) | more than 6 years ago | (#22458128)

Don't make us come over there: http://xkcd.com/307/ [xkcd.com]

Re:Hey! (0)

Anonymous Coward | more than 6 years ago | (#22458926)

Parent was first post of the kind, and modded redundant?

Re:Hey! (0, Redundant)

armareum (925270) | more than 6 years ago | (#22460358)

First in this story maybe, but it's been seen many many times before. IT'S NOT FUNNY ANY MORE!

Re:Hey! (0)

Anonymous Coward | more than 6 years ago | (#22460362)

Gotta love books written decades ago:

"That's no moon!" he ejaculated.

or:

"But doctor, I have erectile dysfunction," he ejaculated.
 

mmm (0, Offtopic)

beredon (454896) | more than 6 years ago | (#22458064)

mmmmmm, enchiladas

Soaking up ejected debris? (1)

addictedavi (898607) | more than 6 years ago | (#22458106)

Most suggestive headline I've read all day.

Re:Soaking up ejected debris? (3, Funny)

Max Littlemore (1001285) | more than 6 years ago | (#22458520)

heh heh "A-ring" heh heh "Moon" heh heh heh...

Re:Soaking up ejected debris? (1)

plover (150551) | more than 6 years ago | (#22459272)

So the "A" ring is really just the astronomical equivalent of a crusty sock under Saturn's bed? Gross. Now I gotta go wash my telescope.

Is This New? (5, Informative)

CheshireCatCO (185193) | more than 6 years ago | (#22458162)

I'm not sure that this is really news. I can vaguely recall people talking about exactly this sort of thing happening in papers from years ago. I'm not 100% certain that the topic was E ring particles, but I rather thing that it is. Sure, before we found the plume on Enceladus, that moon's connection wasn't apparent, but the issue of contamination of the A ring has come up before. I even remember discussion as to how far into the A ring you'd have to go before the contamination stopped. (Which probably played back into older photometric and spectroscopic measurements of the outer A ring, which has a a rather distinct character.)

It's a bit difficult to tell from the article what the point of the new research is, but I will say that even confirming this with new, perhaps more telling, measurements is still useful result, even if I'm remembering correctly and this isn't a new idea.

Re:Is This New? (0, Offtopic)

Mr.Ballmer (1241256) | more than 6 years ago | (#22458270)

Nothing is new about any of this! Pray that MS and Yahoo get together! http://fakesteveballmer.blogspot.com/ [blogspot.com]

Heh, two "sponges" in one day (1)

iminplaya (723125) | more than 6 years ago | (#22458228)

Betcha they got no CO2 [slashdot.org] up there.

time to become a gas station (1)

Coraon (1080675) | more than 6 years ago | (#22458262)

between the hydrocarbons, the ice to produce hydrogen and now the plasma its really starting to sound like the place to open a cosmic truck stop is Saturn, its got like tonnes of energy sources waiting to be used.

Re:time to become a gas station (1)

SubOptimalUseCase (927514) | more than 6 years ago | (#22466342)

Yea, but can I get really strong coffee for late night orbiting, and maybe a couple of those "plasma flaps" for my orbiter - you know, the ones with the naked lady sillouettes?

A-ring, E-ring ... (1)

justinlee37 (993373) | more than 6 years ago | (#22458286)

What about the O-ring?

Re:A-ring, E-ring ... (2, Funny)

Dunbal (464142) | more than 6 years ago | (#22458348)

it will need to be replaced in a few years.

Re:A-ring, E-ring ... (1)

KlaymenDK (713149) | more than 6 years ago | (#22460886)

Yeah, when I read the headline I thought great, finally some space junk that's actually cleaning up up there ... then of course I read the next sentence.

That's no moon ... (-1, Redundant)

The Sith Lord (111494) | more than 6 years ago | (#22458406)

... oh god ...

I'm sorry. Sorry.

I'm so sorry.

Please let me live !

I'm at work, I'm bored, and though I'll try to be funny.

Please God ! I want to live !!!

Hubble Images (0, Troll)

russlar (1122455) | more than 6 years ago | (#22458534)

Images from the Hubble Space Telescope can be seen here. [omnomnomnom.com]

Saturn says... (0)

VoltageX (845249) | more than 6 years ago | (#22458878)

Om nom nom nom!

Too Small (1)

Tablizer (95088) | more than 6 years ago | (#22459028)

The Saturnians' plan to inject Coke and Mentos into Enceladus was a brilliant move to produce rings and revive their once-sagging tourism trade.

Seriously, I wonder how such a relatively small moon like Enceladus can have such strong tidal heating. It just seems too puny for that kind of thing.
     

Oblig. (1)

cslax (1215816) | more than 6 years ago | (#22459314)

I, for one, welcome our new debris absorbing overlords.

Thuktun Flishithy (0)

Anonymous Coward | more than 6 years ago | (#22459708)

The Fithp are coming...

ice geysers? (3, Informative)

NotZed (19455) | more than 6 years ago | (#22459428)

Do they really look like geysers to anybody? Wouldn't they be more columnar, or conical?

If anything it looks like the solar corona, or a comet perhaps?

ahh, here we go ... 2 years ago, same story - with a cometary conclusion:

http://www.astrobio.net/news/modules.php?file=article&name=News&op=modload&sid=1797 [astrobio.net]

Re:ice geysers? (1)

CheshireCatCO (185193) | more than 6 years ago | (#22462386)

Except that even in the very quote where Torrence makes the comet analogy, *he* calls them geysers and then proceeds to point out why this very much is not a comet.

I don't often hear "geyser" used for Enceladus, by the way. (I think it was tossed around early after the discovery, and then shot down for technical reasons.) "Plume" refers to the whole eruption and "jet" to the individual sources that merge to form the plume. That's certain the nomenclature used in the imaging team and, from what I've heard, around the Cassini project.

Re:ice geysers? (2, Insightful)

susano_otter (123650) | more than 6 years ago | (#22464276)

Do they really look like geysers to anybody? Wouldn't they be more columnar, or conical?

What is it about a columnar or conical jet that makes them not geysers?

Noone understands? (0)

Anonymous Coward | more than 6 years ago | (#22459628)

I think the lack of care or knowledge about this particular subject is leading to a lot of bad jokes and off topic comments. Muck like this one, hence the AC.

Goatse (0)

Anonymous Coward | more than 6 years ago | (#22459896)

There's a good joke about goatse in there but I'll spare you the imagery.

Wha.....? (1)

IHC Navistar (967161) | more than 6 years ago | (#22460774)

Isn't the A-ring what surrounds the A-hole?

Think I saw this on the Frontier flight (1)

davidsyes (765062) | more than 6 years ago | (#22460878)

near the end of January.
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