Close views show Saturn's rings in unprecedented detail

January 30, 2017
This Cassini image features a density wave in Saturn's A ring (at left) that lies around 134,500 km from Saturn. Density waves are accumulations of particles at certain distances from the planet. This feature is filled with clumpy perturbations, which researchers informally refer to as "straw." Credit: NASA/JPL-Caltech/Space Science Institute

Newly released images showcase the incredible closeness with which NASA's Cassini spacecraft, now in its "Ring-Grazing" orbits phase, is observing Saturn's dazzling rings of icy debris.

The views are some of the closest-ever of the outer parts of the main rings, giving scientists an eagerly awaited opportunity to observe features with names like "straw" and "propellers." Although Cassini saw these features earlier in the mission, the spacecraft's current, special orbits are now providing opportunities to see them in greater detail. The new images resolve details as small as 0.3 miles (550 meters), which is on the scale of Earth's tallest buildings.

Cassini is now about halfway through its penultimate mission phase—20 orbits that dive past the outer edge of the main ring system. The ring-grazing orbits began last November, and will continue until late April, when Cassini begins its grand finale. During the 22 finale orbits, Cassini will repeatedly plunge through the gap between the rings and Saturn. The first finale plunge is scheduled for April 26.

For now, the veteran spacecraft is shooting past the outer edges of the rings every week, gathering some of its best images of the rings and moons. Already Cassini has sent back the closest-ever views of small moons Daphnis and Pandora.

This image from NASA's Cassini mission shows a region in Saturn's A ring. The level of detail is twice as high as this part of the rings has ever been seen before. The view contains many small, bright blemishes due to cosmic rays and charged particle radiation near the planet. Credit: NASA/JPL-Caltech/Space Science Institute

Some of the structures seen in recent Cassini images have not been visible at this level of detail since the spacecraft arrived at Saturn in mid-2004. At that time, fine details like straw and propellers—which are caused by clumping ring particles and small, embedded moonlets, respectively—had never been seen before. (Although propellers were present in Cassini's arrival images, they were actually discovered in later analysis, the following year.)

Cassini came a bit closer to the rings during its arrival at Saturn, but the quality of those arrival images (examples: 1, 2, 3) was not as high as in the new views. Those precious few observations only looked out on the backlit side of the rings, and the team chose short exposure times to minimize smearing due to Cassini's fast motion as it vaulted over the ring plane. This resulted in images that were scientifically stunning, but somewhat dark and noisy.

In contrast, the close views Cassini has begun capturing in its ring-grazing orbits (and soon will capture in its Grand Finale phase) are taking in both the backlit and sunlit side of the rings. Instead of just one brief pass lasting a few hours, Cassini is making several dozen passes during these final months.

This image shows a region in Saturn's outer B ring. NASA's Cassini spacecraft viewed this area at a level of detail twice as high as it had ever been observed before. And from this view, it is clear that there are still finer details to uncover. Credit: NASA/JPL-Caltech/Space Science Institute

"As the person who planned those initial orbit-insertion ring images—which remained our most detailed views of the rings for the past 13 years—I am taken aback by how vastly improved are the details in this new collection," said Cassini Imaging Team Lead Carolyn Porco, of Space Science Institute, Boulder, Colorado. "How fitting it is that we should go out with the best views of Saturn's rings we've ever collected."

After nearly 13 years studying Saturn's rings from orbit, the Cassini team has a deeper, richer understanding of what they're seeing, but they still anticipate new surprises.

"These close views represent the opening of an entirely new window onto Saturn's rings, and over the next few months we look forward to even more exciting data as we train our cameras on other parts of the rings closer to the planet," said Matthew Tiscareno, a Cassini scientist who studies Saturn's rings at the SETI Institute, Mountain View, California. Tiscareno planned the new images for the camera team.

Launched in 1997, Cassini has been touring the Saturn system since arriving in 2004 for an up-close study of the planet, its rings and moons, and its vast magnetosphere. Cassini has made numerous dramatic discoveries, including a global ocean with indications of hydrothermal activity within the moon Enceladus, and liquid methane seas on another moon, Titan.

This image shows a region in Saturn's outer B ring. NASA's Cassini spacecraft viewed this area at a level of detail twice as high as it had ever been observed before. Credit: NASA/JPL-Caltech/Space Science Institute

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22 comments

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archytype_net
1 / 5 (1) Jan 31, 2017
I reckon the ring spacing has to do with harmonics.
BrettC
1 / 5 (1) Jan 31, 2017
Maybe, or Gravity aberrations. Or, now I'll concede this is a bit "Out there", what if they are being set in such a way to send us a message. What if there is a message encoded in the ring spacing. That would be interesting! It would at least make a good Science Fiction plot device.
cantdrive85
1.3 / 5 (13) Jan 31, 2017
The rings and no aspect of them have absolutely anything to do with gravity. Rings were reproduced by Birkeland in the lab about 100 years ago, it's an electric discharge phenomena.
Ebo2
4 / 5 (8) Feb 02, 2017
Just on a hunch i 3D scanned that image, printed it off on a 12inch diameter disk and threw it onto my turntable.. here's what i faintly heard:
[crackles and dust pops] "....and she's buy-ing a stairway to heaven..."

;)

jonesdave
4.6 / 5 (9) Feb 02, 2017
The rings and no aspect of them have absolutely anything to do with gravity. Rings were reproduced by Birkeland in the lab about 100 years ago, it's an electric discharge phenomena.


Lol. I'd be interested to know how Birkeland managed to cause ice to levitate! In case you haven't heard, that is what the rings are mostly composed of. Cassini has been looking at them for years, with all sorts of instruments. No surprise that they see water ice, and no surprise that they see no electric discharges.

"Consistently with previous studies, we find that the near-infrared spectra of all main ring regions are dominated by water ice, with a typical regolith grain radius of 5–20 μm, while the steep decrease in visual reflectance shortward of 0.6 μm is suggestive of an organic contaminant, perhaps tholin-like."

http://webpages.u...2008.pdf
cantdrive85
1 / 5 (8) Feb 03, 2017
jonesdumb,
The fact it's mostly water in no way precludes this from being an ED phenomena.
And since you insist it's not an ED phenomena, explain the spokes without invoking DM or some other imaginary stuffs.
bschott
5 / 5 (5) Feb 03, 2017
The fact it's mostly water in no way precludes this from being an ED phenomena.

But ya know what does? physics. Below is the Wiki page on electrical discharge, there are several types but none of them apply to saturns rings.

https://en.wikipe...ischarge

Ironically, the word "discharge" means something is emitted or "let go"....other than reflected light....what are the rings producing that can be classified as a discharge?
jonesdave
4.2 / 5 (5) Feb 03, 2017
jonesdumb,
The fact it's mostly water in no way precludes this from being an ED phenomena.
And since you insist it's not an ED phenomena, explain the spokes without invoking DM or some other imaginary stuffs.


Yes, it does. They are solid material, they are not self-luminous, and they follow Keplerian orbits. They in no way resemble what Birkeland saw 100 years ago in his experiments.
Whether the **transient** spokes might be an **electrostatic** effect has been proposed before, from memory. If they are, that means that they are caused BY the material in the rings, not the cause OF the rings.
We quite probably see electrostatic dust levitation on the Moon; does this levitation cause the Moon to exist? That is essentially what you are proposing.
And, just for clarity, the E-ring is also water ice. That comes from Enceladus. You know, from the water ice being ejected there that some EUers like to call 'electric discharges'?
Invisible discharges everywhere, it seems.
cantdrive85
1.5 / 5 (8) Feb 03, 2017
Here you are, the rings raining (discharging) to Saturn.
https://phys.org/...urn.html
And the fluorescent rings emitting x-rays...
https://arxiv.org.../0505409
cantdrive85
1.5 / 5 (8) Feb 03, 2017
Invisible discharges everywhere, it seems.

Invisible to the wilfully ignorant.
https://en.m.wiki...adus.jpg
cantdrive85
1 / 5 (6) Feb 03, 2017
"It seems almost incredible that such a ring of cosmic dust should be able to exist for ever, so to speak, without other governing forces than gravitation…" Kristian Birkeland
bschott
5 / 5 (5) Feb 03, 2017
Fluorescent scattering of solar X-rays from oxygen atoms in the H2O icy ring material is the likely source mechanism for ring X-rays

Directly from your link, this does not support X-rays generated by an electrical discharge.
Here you are, the rings raining (discharging) to Saturn.
https://phys.org/...urn.html

It is also called a discharge when rain clouds on earth dump water...if you choose to call the ring rain an ED, and the rings an ED, and your theory now has an electrical discharge creating an electrical discharge, well sir.... basic electrical theory may not agree. That the ring rain is composed of ions and follows a magnetic field (per your first link) could classify it as a current or ED. But you didn't say it was the rain in your first post....you claimed the rings were an ED.

jonesdave
4.2 / 5 (5) Feb 03, 2017
"It seems almost incredible that such a ring of cosmic dust should be able to exist for ever, so to speak, without other governing forces than gravitation…" Kristian Birkeland


And he was obviously wrong. Get over it. It was a hundred bloody years ago! Why are you still quoting it? He didn't even know what the rings were composed of. Do you not think we have not had better observation and measurement since then? Cassini, maybe? Bloody great telescopes, possibly? An ability to look at them in various wavelengths, perhaps?

Why are you lot so stuck in the past? I've said it before, but what you lot (EU) are doing bears far more similarities to cult worship/ religion, than it does to science.

I'll repeat; the rings of Saturn bear no resemblance to Birkeland's experiment. Unless, that is, he got a bunch of ice to levitate, and somehow become gravitationally bound to his terella, or whatever he used.
jonesdave
3.4 / 5 (5) Feb 03, 2017
Right, for a bit of clarity, here is what Birkeland thought:
From 1911,
.....he discussed the possibility that Saturn's rings were composed of electrons, ions, neutral atoms and molecules, and cosmic dust. Particles with the largest mass relative to their electric charge should be found closer to the planet; those with lower density orbit farther away. These particles soon became electrically neutral, and their orbits become elliptical.


https://books.goo...;f=false

Now, would someone explain to me how that matches up to modern reality? Not that I'm dissing Birkeland; he didn't know what the rings were composed of. This was 8 years after the Wright brothers first flight!
jonesdave
4.2 / 5 (5) Feb 04, 2017
Invisible discharges everywhere, it seems.

Invisible to the wilfully ignorant.
https://en.m.wiki...adus.jpg


Whoops, I missed this nonsense. Still following the EU tradition of science by pareidolia, I see!
What you are seeing there is H2O. Yep, the same stuff that forms the E-ring. Just like Thornhill's electric jets at comets pareidolia, this is just another case of plain old water!
http://adsabs.har...33A1564D
cantdrive85
1.6 / 5 (7) Feb 04, 2017
this is just another case of plain old water!

You seem to fail to understand that the presence of water in no way precludes this event as being a discharge mechanism. First, the likelihood of electrochemistry is high given the proclivity of H and O to combine. Then there was this article; https://phys.org/...ace.html
That article describes the process of electric discharge that occurs between two plasmas, clearly over your head as you fail to grasp the implication. Just as what is observed with laboratory plasmas, that all plasmas behave this way and has been known since the 20's and has been wilfully ignored by astrophysicists ever since in favor of their "ideal gases" guesses. jonesdumb, along with the astrophysicists insist that these plasmas are different, not plasma but gas, yet every time the adequate resources are available it is shown that plasmas actually do behave like plasmas, as shown in the linked article.
jonesdave
4.2 / 5 (5) Feb 04, 2017
^^^^Utter drivel. Where are you getting a discharge from? Where are you getting the O- from? How is it combining with H+ in such numbers? From the solar wind? Lol. We've been down this route before, but closer to the Sun. It doesn't work, remember? The numbers are even worse out there, if your mechanism was possible. Which it isn't. What is the influx of H+ per second? Where are you getting O- from? Will it combine at 400 km/s? Err, no.
Want it to happen on the surface? That reaction will happen even more slowly. You are many, many orders of magnitude out.
A not unexpectedly scientifically illiterate answer from an evangelical neo-Velikovskian woo merchant.
And you wonder why nobody takes you lot seriously.
And what do you think these 'discharges' (lol) would look like at various wavelengths? What temperature are they? Happy to dig out the data for you that shows that they aren't.
Including the s/c flying through them.
jonesdave
4.2 / 5 (5) Feb 04, 2017
^^^^Oh yeah, might want to figure out where the salt is coming from too!
http://www.esa.in...r_plumes

Ouch, 200 kg/s! Want to know how many H2O molecules that is cd? ~7 x 10^27! Now, what is the SW flux out there?
Loon.
cantdrive85
1 / 5 (5) Feb 05, 2017
Will it combine at 400 km/s?...Now, what is the SW flux out there?

This is well within Saturn's magnetosphere, why are you babbling about the SW?
Where are you getting a discharge from?

From this electric current that flows between the two bodies.
cantdrive85
1 / 5 (3) Feb 05, 2017
jonesdave
4.5 / 5 (8) Feb 05, 2017
Will it combine at 400 km/s?...Now, what is the SW flux out there?

This is well within Saturn's magnetosphere, why are you babbling about the SW?
Where are you getting a discharge from?

From this electric current that flows between the two bodies.


Again with the stupidity. What is the flux needed? Where is your O-? Where is your H+? Do you think they would not detect it? How is this impossibly formed ice incorporating salt? I could go on, but its pointless. You guys will just perform all sorts of mental contortions, and believe in any old unscientific nonsense to hang on to your evidence-free, mythology based woo beliefs. Very sad. Very pathetic.
jonesdave
4 / 5 (4) Feb 05, 2017
Here is that link;
https://www.nasa....069.html


Yes, thank you. All jolly interesting, I'm sure. Instead of reading the press release though, perhaps you could have read a pape or twor? Where you would see that it is the ionisation of the **pre-existing** H2O, by charge exchange, that is believed to be the reason for the pickup current.
http://onlinelibr...674/full

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