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Saturn Rings But No Spokes
An anonymous reader writes "Scientists continue to ponder why images of Saturn's rings today lack the 'spokes' or dark radial bands radiating outward and first observed on the Voyager flyby. The Boulder-based Cassini Image Team describes 5 visible moons, plans for the descent probe going into the Titan moon's hydrocarbon-rich atmosphere and the expected orbital entry around Saturn less than 4 months from now."
Saturn is not on teh spoke!!~1
Hydrocarbon-rich atmosphere?
:)
More fuel for my hydrogen-powered
Jeep!
Good times baby
Eve Fairbanks says I drive a hybrid!LOL
Because of Galileo's extemely elliptical orbit -- think of a comet around the sun -- (required because it's mission was to visit most of Jupiter's moons), it's constantly in need of tweaking in the form of thruster firings to keep it from blundering into something (besides Jupiter) while still keeping its antennae pointed towards Earth.
The maneuvering fuel is nearly gone, and the spacecraft components have sustained many tens of times their design tolerances of radiation. Taken together, it's entirely possible that Galileo would soon become uncontrollable and crash somewhere like Eurpoa, where we may one day send probes to search for life. Because Galileo was not sterilized before launch, it would contaminate wherever it ended up, and could cast doubt of any future test results from expeditions there.
(As a testimony to the hardiness of life, microbes on a camera lens or something were brought to and back from the moon, it wasn't until later that they realized someone sneezed on the lens or some nonsense and the damn bugs survived the whole round trip).
While it would be nostalgic to have left Galileo in orbital purgatory around Jupiter, it's not possible to do this with any assurance that it won't later be a hazard. It is fitting, in a way, that Galileo will become part of Jupiter, the target of so much of its (and his) focus. If only NASA would bring the success of this mission into the public spotlight as a way to raise awareness as to its more successful programs.
Coming soon to Saturn - Cassini, July 4, 2004. (Alas, the last of the "great explorer" probes.)
Propz to the GNAA
Saturn may not be on the spoke, but jimmy o'leary definately is.
plenty of 'spooks' though.
consult with/trust in yOUR creators.... get ready to brighten up some more.
Look at this moderation abuse. What's wrong with that comment?
Maybe it got tired of all the stupid kids putting cards in them.
I just heard some sad news on talk radio--Master Distiller Booker T. Noe was found dead in his Bardstown, KY home this morning. There weren't any more details. I'm sure everyone in the Slashdot community will miss him--even if you didn't enjoy his work, there's no denying his contributions to the Art of Distilling Bourbon. Truly an American icon.
I would have modded him +1 informative.
Troll mod is certainly abuse.
Huh?
Perhaps these are actually the rings around Uranus.
I'm sorry, maybe I'm just an idiot, but I don't really see any of the 'spokes' in the image you linked to.
Could somebody paste a big red arrow on there for the outer-space-cluefully-impared, such as myself?
Thanks.
The parent is a troll, or at least off-topic and probably also redundant.
Look at the last line. If you don't know what that acronym is, scan at -1.
It appears that this is a copy of an old message from back in the August 2003 time-frame.
HCG 50a = 2MASX J11170638+5455016
11h17m06.4s +54d55m02s
But I don't see the "spokes" in the Voyager images everyone is talking about. I'm looking for dark lines extending from the center of the rings outward, like the spokes on a bicycle wheel, but I don't see any. Can someone explain for me in some detail what the spokes look like?
There were no real current Astonomy Picture of the Day references so I linked to a search on Saturn. This gives quite a few different views of Saturn and some other related material as well.
Use your head, can't you, use your head,
You're on earth, there's no cure for that - S. Beckett
By the way, next summer NASA's Cassini spacecraft, launched in 1997, is scheduled to go into orbit around Saturn and its moons for about four years.
The piggybacking Huygens probe is scheduled to go into the hazy Titan atmosphere and land on the moon's surface (if all goes well). The Huygens probe is geared primarily towards sampling atmosphere. The probe is equipped to take measurements and record images for up to 30 minutes on the surface. But the probe has no legs, so when it sets down on Titan's surface its orientation will be random. And its landing may not be by a site bearing organics.
Please help publicise swpat.org - the software patents wiki
Obviously the Fithp has already left Saturn and is headed to Earth.
Time to start studying those old Orion plans...
The "spokes" are odd disruptions in the rings caused by Saturn's magnetic field rotating through them. They show up as dark patches radiating directly away from Saturn or occasionally arching, and they travel like a wave around Saturn in time with its rotation. It was this timing/speed that tipped astronomers off as to what was causing them, incidentally.
So if the spokes aren't visible now, maybe Saturn's magnetic field is fluctuating/less coherent than normal. It's a gas giant so its field could be less stable than the denser planets. There may be some low-level eg mid-atmosphere storm disrupting the normal field-generating circulations.
Just a thought. IANAA
cheers, Sal
--
Sal
Writings: saltation.blogspot.com
Wravings: go-blog-go.blogspot.com
Perhaps the spokes don't show up because they're not applying those same techniques? I certainly don't see any mention of those techniques in the article in the first link.
libertarianswag.com
This is an offtopic comment: offtopic because it was stolen verbatim from a totally unrelated story:
8 6& cid=7019194
.sig modded up
http://science.slashdot.org/comments.pl?sid=793
It's just an excuse to get the
It's clearly unrelated to this topic. 2 seconds with Google gives us:
8 6& cid=7019194
.sig modded up.
http://science.slashdot.org/comments.pl?sid=793
It's a troll because it's a stolen post used for the purpose of getting a
have been seeing spokes in the rings for quite some time using ground-based telescopes of various sizes. This may be one of those features, like the canals on Mars, that shows up because the eye-brain software processes images differently than the spacecraft ccd-computer does. An article in Sky & Telescope discovered they could reproduce the canal effects using the techniques of registration (stacking), and various applications of wavelets and other processing methods. They concluded our eye-brain mechanism does something similiar in real time at the eyepiece during moments of steady seeing conditions, causing dark lines to be seen where a smoother color gradient actually exists.
The original non-troll post is here
HCG 50a = 2MASX J11170638+5455016
11h17m06.4s +54d55m02s
The post is not exactly a troll and makes sense enough to be moderated as interesting. However, nobody wants to see some idiot gaining karma points by mooching off of some other persons opinions/ideas. Shouldnt there be some mechanism whereby the post is modded up but the poster does not get the mod points? Or at least some reporting interface that will blacklist the poster for having copied the post verbatim...
Note, if the poster had given due credit to the original post, it probably would have been okay.
The Boulder-based Cassini Image Team describes 5 visible moons, plans for the descent probe going into the Titan moon's hydrocarbon-rich atmosphere and the expected orbital entry around Saturn less than 4 months from now.
:-)
It's nice to know that if man ever lands on Titan, there won't be any problem with heating our homes
SpamNet - a spam blocker that really works
Saturn rang? And no one spoke with it? Geez, maybe it woulda told us everything.
Maybe a decent sized object passed through the rings, disturbed them and left.
Either that or some stoned punk aliens were waving their hands in front of the Voyager cameras just to screw with us.
This is my sig.
You morons. The point of the post was to take perfectly good information and make you THINK it is a troll... that was the real troll.
Ahahahah you've all been trolled I'm so fucking cool I could cry!!! Now I can finally move out of my mother's basement and maybe even start talking to girls!!!
In all the APOD picture of Saturn I found a reference to Spokes and a picture that contains them.
Use your head, can't you, use your head,
You're on earth, there's no cure for that - S. Beckett
I was a young engineer at JPL when Voyager 2 encountered Saturn, and I remember when the first photos of the spokes in the rings were displayed in real time on the monitors in the cafeteria. The work on other projects had pretty much ground to a halt while everyone watched the data come in.
Of course, the real time data had no captions, no explanations of what we were seeing, so we had all sorts of guesses - density waves, camera artifact, etc. Once it was apparent that the waves were holding together as the rings rotated and were not being sheared apart, it was clear they were not due to any gravitational effect. Since they moved with the rotation of the planet, the accepted explanation is the magnetic field of Saturn causing the charged dust in the rings to concentrate into visible spokes. As I understand it, the spokes are not a wave phenomenon at all.
10 Bits= $.25
100 Bits= $.50
110 Bits= $.75
1000 Bits= 1 byte
I was wondering if the planetoid and particles could be doing the wave.
Generally these things are oblong rather than spherical. Maybe there is some gravitational coupling between the particle shape and Saturn and/or the other neighboring particles.
The particle could be spinning along their axes perpendiculr to the ring and along the line from the center of Saturn to the particle.
When the particles long axes are aligned perpendicular to the plane of the ring they would look one way (reflect less light perpendicular to the plane of the ring). Then when they rotate with the long axis in the plane of the ring they reflect more light perpendicular to the plane of the ring - they look brighter.
Admitttedly the dipole interaction would be pretty small. But this would allow for no spokes in the sense of ripples in the particle density but still allow us to "see" the spokes.
ticker.js
About 30 seconds after posting the above I found this link, to an abstract of a scientific paper detailing Hubble observations of the spokes.
When will Cassini photograph the monolith on Iapetus.
The Saturnians have taken notice that this vessel is on a trajectory to permanently enter their planetary system [...] If the spacecraft does not alter its course soon, [...]
Or maybe if the spokes aren't visible, it's because someone nicked the Saturnians' bike.
This could also explain the posited incoherence:- rage-choked fist-waving Saturnian hordes milling backwards and forwards under the constant swirling clouds, roaring "Give us back our blurry bike!" at the intruder spacecraft above desperately trying to signal its non-hostile intentions by firing its Attitude Jets.
"<cough><blurt><cough><rrrRRRR!> Dude! In your face! Take your job and shove it up your"
Yes! They're firing! The spacecraft is saved!
--
Sal
Writings: saltation.blogspot.com
Wravings: go-blog-go.blogspot.com
"dammit, we forgot the spokes. Quick, get that guy that colours the martian sky blue to add some in to the new pictures".
"plans for the descent probe going into the Titan moon's hydrocarbon-rich atmosphere and the expected orbital entry around Saturn less than 4 months from now."
All Iraq-related kidding aside, I find this interesting. Saturn is too far out for modern solar energy solutions to be viable, we still haven't figured out the whole fusion thing and hydrogen doesn't like to be cracked out of water. On the other hand, hydrocarbons want to be broken down and we know all about harnessing the energy of that reaction and we'd have uses for the byproducts (soot may not be desirable here on earth but carbon is a pretty good radiation shield). We can do something with this once we get there.
Why are there spokes in the Voyager images but not from Cassini? Because Janeway was a nutcase and mismanaged just about every aspect of her mission!
Anyone who trusts Voyager's telemetry with her in command over even the comparatively primitive computer and sensors Cassini uses is an idiot!
Maybe you're not close enough to see them, or maybe you're in the wrong frequency.
Saturn rang but no-one spoke?
...to see the death star be so neglected and in a sad state.
j pg
http://photojournal.jpl.nasa.gov/jpeg/PIA01968.
No, it's funny to anyone who realizes we are in Iraq just to steal their oil supplies. Too bad American soldiers are dropping as a cost. Good for Halliburton though!!!
Heh heh, the probe landing on Titan is European... I'm sure it won't find any hydro-carbons... the US won't hear of any being found at any rate... :o)
I'm just kidding around. Some folks are way too uptight. Modding down the parent post? Come on, it's funny and had to be said!
-- *~()____) This message will self-destruct in 5 seconds...
All those spokes were made of countless black monoliths that were needed for somethin on Jupiter.
This issue is a bit more complicated than you think.
The bright spokes are seen when the light is forward scattered, which will not be possible until Cassini is further from the sun than Saturn is. Cassini is currently closer, so it should see them dark if it sees them at all. Other posters have provided links to excellent photos of spokes in both phases from the Voyager missions.
"I'm so moist I'm sticking to the leather." -Kermit the Frog on The Late Late Show
Or maybe someone is just covering their tracks:
"Canals? No canals to see here. Just move along..."
"Oops, they saw the pyramids. Quick, hit their probes with the disrupter beam until we get them smoothed over."
"What? They got photos of our rotating homing beacon around Saturn? Dummkopfs! Turn it off next time they get close, you knuckleheads!"
"And next time, don't drain the energy out of their landers at the same time! [mumble...buy them books, send them to school, and they eat the teacher...grumble.]
"Is this Winkhorst a nova criminal?" "No just a technical sergeant wanted for interrogation."
I can't see them either, and I'm enormously grateful to eddie-can-read for posting links to better pictures (below), and to the representative of the Cassini Imaging Team for confirming that it's not a good picture.
As a very, very amateur backyard astronomer, I find that one of the most difficult problems I have in showing non-astronomical friends anything in my telescope, is that very few people will tell you what they are seeing or will say "I can't see it." My telescope is a Cassegrainian, meaning out-of-focus images look like doughnuts. When I show someone Saturn, the conversation invariably goes like this:
"You should see a very small object that looks like the pictures of Saturn in comic books, but much smaller. Do you see it?"
"Yes, I see it."
"Are you sure?"
"Yes, I can see the rings."
"Does it look the way I described it? Very small and the rings tilted at an angle?"
"Yes."
"Please turn this focus knob a little. Did the rings change size?"
"Yes."
"OK, you're not really seeing Saturn yet, please turn the knob back and forth until you get it just as small as you possibly can."
"Ok... um, wrong way... ok, I--OMIGOD! THERE IT IS! It's that little shimmery thing that looks like it has a halo, right?"
They can say "I see it," "I see it," but until I get the reaction of surprise I know they haven't seen it.
"How to Do Nothing," kids activities, back in print!
Damn stoned punk aliens. Always fucking up my stoned scientific research.
Professor Ford.
Does anybody know where I could find a bigger version of the drawing of what it would look like when Huygens decends into Titan's atmosphere. I think it's a really neat picture. Heres a link so that you know what drawing I am referring to http://www.astrobio.net/articles/images/huygens_ed l.jpg
Everyone who's read Footfall knows that the spokes were caused by the exhaust wake of the fithp ship on its way to Earth.
Don't underestimate the power of The Source
and stuck them into Uranus.
Would you like a goatse.cx link with that?
Free as in mason.
your sig - Dooon't... (shakes head, looks like he wants to slap you) speak that language here, you ass-hat. (what Elrond should have said... if you ask me). :P
On most of the pictures that have been released of saturn, it looks like the picture has been flip-flopped horizontally (the left-side is on the right and right-side is on the left). At least to me that is.
When viewed from above, planets orbit counter-clockwise. Cassini's tragectory also follows the planets counter-clockwise orbits.When Cassini approaches Saturn, it will be coming in from behind the planet, it is trying to catch up to it. This means the Sun will be on the left side of the picture, and the dark side of the planet will be on the right.
There are only two reasons that I can think of to explain why the sun in these pictures is coming from the right side.
1) Cassini is actually in front of Saturn.
2) The image is flipped to make the image more asthetically pleasing. Maybe the rings look better this way.
-thenumberone