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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."
Hydrocarbon-rich atmosphere?
:)
More fuel for my hydrogen-powered
Jeep!
Good times baby
Eve Fairbanks says I drive a hybrid!LOL
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.
That's absolutely true. After what happened with the Columbia, NASA really needs to boost public support for their programs. People see the 2 shuttle disasters that have occured as being the bulk of what they accomplished, and that is just wrong.
And of course, I'm not saying what happened isn't tragic. But people dont understand that many astronauts understand that disaster is a possibility, and they're willing to take that chance in the pursuit of the Greater Understanding.
NASA really has to get the PR machine in motion
Are you sure it would send the right message?
It sort of seems to me like saying "unmanned exploration is really successful, but look at how many people we killed with stupid manned exploration, that could have easily been done unmanned".
I've had enough abrasive sigs. Kittens are cute and fuzzy.
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
TO BUY A NEW CAR WOULD MAKE YOU SEXUALLY ATTRACTIVE.
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.
But isn't that the truth? Let's face it, manned exploration IS orders of magnitude more expensive than unmanned, doesn't provide much more benefit from a scientific viewpoint, as is infinitely more tragic when things go wrong. If we still want to do manned exploration because of the "cool factor", then so be it, but let's not lie to ourselves about the facts.
I don't care if it's 90,000 hectares. That lake was not my doing.
It sort of seems to me like saying "unmanned exploration is really successful, but look at how many people we killed with stupid manned exploration, that could have easily been done unmanned".
Well, that's exactly the message many of us would like to get out. Using astronauts is hot stuff for the evening news but otherwise is rarely of much value. Even the "rescue missions" for things like the Hubble probably don't break even. The development and maintenance cost of the shuttles, space suits, manned safety environment, etc., has gotta be more than sending up full replacement systems.
https://app.box.com/WitthoftResume Code: https://github.com/cellocgw
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
Agreed.
I think that a well-trained geologist/astronaut could pull far more information from a short walk on mars than those rovers could their whole time on the surface. Besides being infinitely more maneuverable than any robot, living astronauts can devise new experiments and fix things when they go wrong. Anything a robot can do, an astronaut in a space suit can do BETTER by several orders of magnitude.
Now, when things go wrong, it is much less tragic to lose a robot than it is to lose a space crew. However, any crew embarking on such an expedition will be fully cognizant of the risks, and I am sure that even if the trip was a guaranteed one-way ticket to mars that qualified volunteers could still be found.
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
Is is me or the planet seems to overlap the rings. On the bottom it is over the rings and on the top is it also over the rings.
Is that a doctored photo.
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.
Anything a robot can do, an astronaut in a space suit can do BETTER by several orders of magnitude.
I doubt that.
First: No astronaut likes to take 10000 examples and analyses them 10000 times. A robot doesn't complain. A robot doesn't get tired. A human does.
Second: A robot can be build adapted to the martian surface: A third the weight for the same mass, no breathable air, sandy environment... For a human, you have to put lots of technology into the space suit to adapt to the martian environment, and the astronaut is occupied carrying it around instead of performing experiments. And working in a space suit is not as easy as just with a labor suit.
Third: A robot can have everything builtin needed to perform analysis. You can design everthing in a size fit to the experiment you are planning. For a man you have to have everthing in the size a human needs it to handle. A human may not be able to perform all experiments during the walk outside, she has to carry her martian examples into the space station and work in the lab, which takes much longer.
The only thing humans are better than robot is to react at unexpected situations. But since the experiments are already preplanned on earth and the space ship is designed for and loaded with the equipment for exactly those experiments, humans don't have much chance to adapt to unexpected situations. What unexpected situations anyway? Suddenly a martian jumping at people? Basicly there are two types of unexpected situations a human could be forced to react on: a) something dangerous happens. Then be glad you just loose a robot. b) there is a chance to analyse something you didn't expect to be there. Then the human doesn't have the equipment to analyse either (and because we don't send McGuyver, he can't built it out of martian dirt). And there is still the earth station, and most of the robots are reprogrammable and remotely guidable anyway, so you may be able to adapt the experiment to the new situation.
With the ESA Beagle we had a situation where a human being around may have helped. She could just take the beagle probe and turn it back on after it failed somehow. But it's much cheaper to just send a second beagle probe to Mars than to send and bring back a human being.
About 30 seconds after posting the above I found this link, to an abstract of a scientific paper detailing Hubble observations of the spokes.
NASA really has to get the PR machine in motion
Please add one key adjective to your request: "NASA really has to get the honest PR machine in motion". It's one thing to try to make science and exploration more interesting to non-science people. It's another to spin every news story so it becomes unbelievable.
(I don't have a tinfoil hat. Really.)
The only thing humans are better than robot is to react at unexpected situations.
[snip]
What unexpected situations anyway? Suddenly a martian jumping at people?
Good one, because, as we all know, nothing unexpected ever happens in space.
Let's see...
PROBLEM: Dust buildup on solar panels
Robot: Screwed because no way to clean it off.
Human: Wipes dust off
PROBLEM: Martian dirt is sticky. Is it because of brine, or is it anelectrostatic thing?
Robot: Takes a closeup picture. Can't tell definitively. Debate ongoing.
Human: Reaches down, touches dirt with glove, has a closer looks, problem solved in two seconds.
Aside: what's the latest story on that dust? I haven't bothered to read up since the last 'brine' hypotheses hit the news.
PROBLEM: Dirt has a crust on it, want to take a look what's under the dust.
Robot: Fixes five wheels in place, while spinning the sixth to break the crust.
Human: Takes a spade...
PROBLEM: Crater wall is steep, interesting deposits halfway down (let's presume here).
Robot: Takes a zoomed-in picture but cannot climb down.
Human: Climbs down, samples deposits, locates water.
The presumption that we could build a robot with the same data-gathering capabilities as a human equipped with an array of scientific equipment is absolutely preposterous, at least in this day and age.
No astronaut likes to take 10000 examples and analyses them 10000 times
No kidding, that's what robots are best suited for, at least right now. Presumably, if any such activity were planned, the astronaut would bring an auto-sampling machine of some sort with them.
Maybe in the future we'll build robots that can gather data as well as a human, but that future is still a ways off.
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.
I think that a well-trained geologist/astronaut could pull far more information from a short walk on mars than those rovers could their whole time on the surface.
But for the same price as one well-trained geologist/astronaut, you'd get a *hundred* rovers spread all over Mars. You must compare 1 with 100, not 1 with 1.
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...
any crew embarking on such an expedition will be fully cognizant of the risks
Yeah, the same way those Shuttle crews were kept fully informed of aware of the risks by the NASA administration.
Dialectician. Archology.
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
Not really: look at the current unmanned rovers on Mars. There is a TEAM of geologists picking spots for it to check, analysing the data it discovers, etc. If you send a geologist there, you have to pick one who is both qualified AND can meet the requirements for becoming an astronaut.
Not only that, but there are way more issues with having a person there than a robot. A robot carries a RISK of biocontamination. A human carries an eventual CERTAINTY of this.
Im not saying Im against manned expeditions, but like the previous poster said, lets not fool ourselves that we support it for anything other than the cool factor.
Manipulate the moderator system! Mod someone as "overrated" today.
Well, I think we have to ask ourselves about the real purpose of the space program. The fact is that space science has few useful applications on Earth (despite the spinoffs which NASA keeps bragging about), and if science were our only goal, we'd be better off spending the money on other projects. Heck, even fusion reactors and particle accelerators would give us more bang for the buck.
No, I think that the real reason to send people into space is so people can be in space. Earth is starting to get too small for us, and there's always the risk of some global disaster, so people should think about colonizing the solar system (and, eventually, other systems). And while sending robots to Mars may teach us a bit about Mars, what we really need to know is how humans could live on Mars, and the simplest way to figure that out is to send a human.
Oh yeah, and in response to your sig:
The Problem with Instant Runoff Voting
Condorcet: A Better Election Method
All it takes is nukes and nerves.
Any astronaut who doesn't know it's dangerous to get in a machine older than the family car & take it to 17,500 mph is an idiot. They know the risks.
That's absolutely true. After what happened with the Columbia, NASA really needs to boost public support for their programs. People see the 2 shuttle disasters that have occured as being the bulk of what they accomplished, and that is just wrong.
And of course, I'm not saying what happened isn't tragic. But people dont understand that many astronauts understand that disaster is a possibility, and they're willing to take that chance in the pursuit of the Greater Understanding.
NASA really has to get the PR machine in motion
I totally agree. Its not like all other forms of transportation don't kill people. We just had a ship explode yesterday in the ocean. The Titanic sank long ago. Does that mean we should stop using them & go back to the drawing board for safer ships?
Two roads diverged in a wood, and I - I took the one the bus load of girls just went down.
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
Assuming it "could have easily been done unmanned", you'd be right. But, you're not.
There are many things that can be done by a sentient explorer that can't by a dumb-assed robot. Robots also jam.
The Brooklyn and San Fran bridges cost many times more lives than the entire U.S. space program. But, we should wait until we have robots to build new bridges, right?
Get your priorities in order.
Why are you flaming me? I didn't take a position in this, I just said what message it might send.
I've had enough abrasive sigs. Kittens are cute and fuzzy.
>>Anything a robot can do, an astronaut in a space suit can do BETTER by several orders of magnitude.
>But for the same price as one well-trained geologist/astronaut, you'd get a *hundred* rovers spread all over Mars. You must compare 1 with 100, not 1 with 1.
When the original poster says an astronaut is better by "several orders of magnitude", s/he is, by definition, comparing one astronaut with several hunderd or thousand rovers.
and stuck them into Uranus.
Would you like a goatse.cx link with that?
Free as in mason.
Whee! troll alert! :-p
Another excellent informative post, except for the fact that the article is talking about *cassini* and *Saturn*, not galileo and jupiter, and hence the parent is totally offtopic.
You are in a twisty maze of processor lines, all alike.
There is a lot of hype here.
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