Groundbreaking science emerges from ultra-close orbits of Saturn

Groundbreaking science emerges from ultra-close orbits of Saturn
NASA's Cassini spacecraft in orbit around Saturn. Credit: NASA/JPL-Caltech Credit: NASA/JPL-Caltech

New research emerging from the final orbits of NASA's Cassini spacecraft represents a huge leap forward in our understanding of the Saturn system—especially the mysterious, never-before-explored region between the planet and its rings. Some preconceived ideas are turning out to be wrong while new questions are being raised.

Six teams of researchers are publishing their work Oct. 5 in the journal Science, based on findings from Cassini's Grand Finale. That's when, as the spacecraft was running out of fuel, the mission team steered Cassini spectacularly close to Saturn in 22 orbits before deliberately vaporizing it in a final plunge into the atmosphere in September 2017.

Knowing Cassini's days were numbered, its mission team went for gold. The spacecraft flew where it was never designed to fly. For the first time, it probed Saturn's magnetized environment, flew through icy, rocky ring particles and sniffed the atmosphere in the 1,200-mile-wide (2,000-kilometer-wide) gap between the rings and the cloud tops. Not only did the flight path push the spacecraft to its limits, the new findings illustrate how powerful and agile the instruments were.

Many more Grand Finale science results are to come, but here are some of today's highlights:

  • Complex organic compounds embedded in water nanograins rain down from Saturn's rings into its upper atmosphere. Scientists saw water and silicates, but they were surprised to see also methane, ammonia, carbon monoxide, nitrogen and carbon dioxide. The composition of the organics is different from that found on moon Enceladus—and also different from that on moon Titan, meaning there are at least three distinct reservoirs of organic molecules in the Saturn system.
  • For the first time, Cassini saw up close how rings interact with the planet and observed inner-ring particles and gases falling directly into the atmosphere. Some particles take on electric charges and spiral along lines, falling into Saturn at higher latitudes—a phenomenon known as "ring rain." But scientists were surprised to see that others are dragged quickly into Saturn at the equator. And it's all falling out of the rings faster than scientists thought—as much as 22,000 pounds (10,000 kilograms) of material per second.
  • Scientists were surprised to see what the material looks like in the gap between the rings and Saturn's atmosphere. They knew that the particles throughout the rings ranged from large to small. But the sampling in the gap showed mostly tiny, nanometer-sized particles, like smoke, suggesting that some yet-unknown process is grinding up particles.
  • Saturn and its rings are even more interconnected than scientists thought. Cassini revealed a previously unknown electric-current system that connects the rings to the top of Saturn's atmosphere.
  • Scientists discovered a new radiation belt around Saturn, close to the planet and composed of energetic particles. They found that while the belt actually intersects with the innermost ring, the is so tenuous that it doesn't block the belt from forming.
  • Unlike every other planet with a magnetic field in our Solar System, Saturn's magnetic field is almost completely aligned with its spin axis. The new data shows a magnetic-field tilt of less than 0.0095 degrees. (Earth's magnetic field is tilted 11 degrees from its spin axis.) According to everything scientists know about how planetary magnetic fields are generated, Saturn should not have one. It's a mystery that physicists will be working to solve.
  • Cassini flew above Saturn's magnetic poles, directly sampling regions where radio emissions are generated. The findings more than doubled the number of direct measurements of radio sources from the planet, one of the few non-terrestrial locations where scientists have been able to study a radio-generation mechanism that is believed to operate throughout the universe.
Groundbreaking science emerges from ultra-close orbits of Saturn
NASA's Cassini spacecraft dives between Saturn and its innermost rings, as part of the mission's Grand Finale. Credit: NASA/JPL-Caltech

For the Cassini mission, the science rolling out from Grand Finale orbits more than justifies the calculated risk of diving into the gap—skimming the upper atmosphere and skirting the edge of the inner rings, said Cassini Project Scientist Linda Spilker.

"Almost everything going on in that region turned out to be a surprise," Spilker said. "That was the importance of going there, to explore a place we'd never been before. And the expedition really paid off—the data is tremendously exciting."

Analysis of Cassini data from the spacecraft's instruments will be ongoing for years to come, helping to paint a clearer picture of Saturn.

"Many mysteries remain, as we put together pieces of the puzzle," Spilker said. "Results from Cassini's final orbits turned out to be more interesting than we could have imagined."

Groundbreaking science emerges from ultra-close orbits of Saturn
A few of the findings from Cassini's direct sampling: complex organics rain down from Saturn's rings; inner-ring particles take on electric charges and travel along magnetic-field lines; newly revealed electric-current system and radiation belt; and up-close measurement of Saturn's near-zero magnetic-field tilt. Credit: NASA/JPL-Caltech

The papers published in Science are:

"Chemical interactions between Saturn's atmosphere and its rings," by J.Hunter Waite, et.al.

"D-Ring dust falling into Saturn's equatorial ionosphere and ," by Donald Mitchell, et.al.

"In-situ collection of dust grains falling from Saturn's rings into its ," by Hsiang-Wen Hsu, et.al.

Groundbreaking science emerges from ultra-close orbits of Saturn
This illustration imagines the view from NASA's Cassini spacecraft during one of its final dives between Saturn and its innermost rings, as part of the mission's Grand Finale. Credit: NASA/JPL-Caltech

"A radiation belt of energetic protons located between Saturn and its rings," by Elias Roussos, Peter Kollmann, et.al.

"Saturn's magnetic field revealed by the Cassini Grand Finale," by Michele Dougherty, et.al.

"The low frequency source of Saturn's Kilometric Radiation (SKR)," by Laurent Lamy, et.al.

On Oct. 4, as the Science publication embargo lifts, articles describing research complementary to these findings will post online in Geophysical Research Letters (GRL), a journal of the American Geophysical Union (AGU).


Explore further

In its final days, Cassini bathed in 'ring rain'

More information: J. H. Waite et al. Chemical interactions between Saturn's atmosphere and its rings, Science (2018). DOI: 10.1126/science.aat2382

D. G. Mitchell et al. Dust grains fall from Saturn's D-ring into its equatorial upper atmosphere, Science (2018). DOI: 10.1126/science.aat2236

Hsiang-Wen Hsu et al. In situ collection of dust grains falling from Saturn's rings into its atmosphere, Science (2018). DOI: 10.1126/science.aat3185

E. Roussos et al. A radiation belt of energetic protons located between Saturn and its rings, Science (2018). DOI: 10.1126/science.aat1962

Michele K. Dougherty et al. Saturn's magnetic field revealed by the Cassini Grand Finale, Science (2018). DOI: 10.1126/science.aat5434

L. Lamy et al. The low-frequency source of Saturn's kilometric radiation, Science (2018). DOI: 10.1126/science.aat2027

Geophysical Research Letters: agupubs.onlinelibrary.wiley.co … 8007.CASSINI_FINALE1

Citation: Groundbreaking science emerges from ultra-close orbits of Saturn (2018, October 5) retrieved 26 August 2019 from https://phys.org/news/2018-10-groundbreaking-science-emerges-ultra-close-orbits.html
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Oct 05, 2018
Kristina Birkeland and his Little Terella experiments win again. The fact the rings are electric is not a surprise if you had been paying attention.

Oct 08, 2018
LOL Yes, I read it too, CD85 - Electric Currents. Just a little more and you might get some satisfaction that Birkeland was right, all along. As long as the science journals don't decide to withhold relevant data or publish only the data that suits them and the Standard Model or ........


Oct 08, 2018
@cd, Kristina? Really.

@SEU, Phys.org (including predecessor physorg.com) has been posting articles about Saturn's rings and electrical activity as early as 2005. The fact that you think this is not only not mainstream science but is somehow being suppressed would be amusing if it wasn't a small part of a flood of inanity you've unleashed here recently.

https://phys.org/...urn.html
https://phys.org/...ory.html
https://phys.org/...deo.html
https://phys.org/...mer.html
https://phys.org/...ini.html
https://phys.org/...ado.html
https://phys.org/...kes.html
https://phys.org/...ess.html

Oct 08, 2018
@cd, Kristina? Really

What are you gonna do? Auto spell gets me all the time. Needless to say, it is hardly intuitive.
Phys.org (including predecessor physorg.com) has been posting articles about Saturn's rings and electrical activity as early as 2005.

One of these days the plasma ignoramuses will figure out how these things get charged. Kind of amusing barakn putting up several links where they acknowledge the charges but the scientists are continuously perplexed how the state is achieved.

Oct 08, 2018
One of these days the plasma ignoramuses will figure out how these things get charged.


Real scientists already know how they get charged. It is blowhards like you that have no clue about it.

Oct 08, 2018
jones, I will rate you a 3 - only because I feel sorry for you as you deny any possibility that, at least, parts of EU could very well be spot on, and that your rantings against CD will be proven to be unfounded and unwarranted in the coming years of discovery.

As a scholar, about the only thing that I have learnt from you is how to use filthy language and how to ad hominem people to death. That is all you are about. But thanks for the lessons in incivility. I will not follow your lead. I have already noticed that you are an arse-kisser as regards to SpookyOtto and Captain Chickenshit and their psychopathic maneuvering, but that was expected.

Oct 08, 2018
@cd, Kristina? Really.

@SEU, Phys.org (including predecessor physorg.com) has been posting articles about Saturn's rings and electrical activity as early as 2005. The fact that you think this is not only not mainstream science but is somehow being suppressed would be amusing if it wasn't a small part of a flood of inanity you've unleashed here recently.

https://phys.org/...urn.html
says barakn

As I have only signed on to this website as of 2013, I have obviously missed those forums/articles that were published in 2005.
And don't presume to know what I am thinking when you have no idea who I am. A flood of inanity is what is posted by thespookofotto1923 and Captain Chickenshit, and sometimes, jonesdave.
But I have rarely seen YOU spouting anything valid about science, and it seems like all you are doing in this website is to lurk about - waiting to make accusations.


Oct 08, 2018
......at least, parts of EU could very well be spot on,......


Not a chance. Nobody sufficently qualified to come up with any real science that isn't already known to mainstream. That is why the few real scientists that have looked at it, will tell you the same as me - it is utter nonsense.

Oct 08, 2018
A flood of inanity is what is posted by thespookofotto1923 and Captain Chickenshit, and sometimes, jonesdave.


Really, clay boy? Show me what inanity I have posted, and I'll show you the supporting scientific literature. Which is more than you, or the other cranks, can do.


Oct 08, 2018
Real scientists already know how they get charged. It is blowhards like you that have no clue about it.

jonesdumb attempts at his revisionist history once again, if these so called scientists had a clue they would unlikely make statements such as;
"We had convinced ourselves that conditions wouldn't be right for seeing spokes on the lit side of the rings until about 2007," Porco said. "But this finding seems to be telling us that conditions on the dark side of the rings are almost as good right now for seeing spokes."
Or articles that make statements such as;
"There is no commonly accepted theory for the creation of spokes."
But to listen to jonesdumb they have it all figured out...LOL!

Oct 08, 2018
Mainstream science is a tad bit similar to the American mainstream media where each publication follows the lead of other mainstream media (MSM) and when all of them have copied off each other, they consider it as having reached a 'consensus', no matter how false the news story is, and the fact that not one of them had seriously investigated and dug up the truth of the matter.
Laziness, complacency, dependence on other news outlets, are what the MSM does.

Many scientists do similar work, and it is only the scientists/researchers who CARE enough about the Truth to tirelessly examine EVERY possibility, that REAL science is worked out and the work toward real discoveries can be accomplished.
So "electric currents" are real, and if it happens at Saturn, it could likely happen in many places under many conditions.

Oct 08, 2018
A flood of inanity is what is posted by thespookofotto1923 and Captain Chickenshit, and sometimes, jonesdave.


Really, clay boy? Show me what inanity I have posted, and I'll show you the supporting scientific literature. Which is more than you, or the other cranks, can do.

says jones

You are completely unaware that you post inanities each time that you include ad hominem, invectives and unfounded accusations in the majority of your posts, while you believe that your incivility is self-correcting just because you have included a tidbit or two of science articles that you had read, and possibly assimilated.

You are also completely unaware that you come off as a fool to the many who are serious thinkers, and those who will read these forums in the future.

Oct 08, 2018
Real scientists already know how they get charged. It is blowhards like you that have no clue about it.

jonesdumb attempts at his revisionist history once again, if these so called scientists had a clue they would unlikely make statements such as;
"We had convinced ourselves that conditions wouldn't be right for seeing spokes on the lit side of the rings until about 2007," Porco said. "But this finding seems to be telling us that conditions on the dark side of the rings are almost as good right now for seeing spokes."
Or articles that make statements such as;
"There is no commonly accepted theory for the creation of spokes."
But to listen to jonesdumb they have it all figured out...LOL!


You were talking about charged nanograins. That has been known about for donkey's years. And none of the crank brigade have predicted anything, ever, have they? Well, not correctly, anyway.

Oct 08, 2018
Let's see what the ignorant EUist loons, such as cantthink, believe about Saturn;

http://www.everyt...uration/

Lol. And they have the cheek to criticise real scientists?


Oct 08, 2018
You are completely unaware that you post inanities each time that you include ad hominem, invectives and unfounded accusations in the majority of your posts, while you believe that your incivility is self-correcting just because............Yada, yada, yada.


So, you cannot find anything that I have said that is not backed up by real science? Thought not.
On another note, I'm off to Monkey World tomorrow. Would you like me to obtain some chimpanzee crap, and mail it to you? You can source your own clay, and then proceed to create little SEU clones. Let me know.

http://www.monkeyworld.org/


Oct 08, 2018
I did a Search wrt the Spokes. This is more current from 2014. It turns out that they are seasonal and consist of charged dust particles that interact with Saturn's magnetic field. Why they are only seasonal and what happens to them off-seasonally would be something to explore.

https://www.space...oto.html

Oct 08, 2018
I copied the link that jones provided to look at later. Personally the talk of Venus having once orbited Saturn (or was it Jupiter) seems highly unlikely to me.
As I have already given my personal opinion that the planets in the Solar System had arrived from a far off supernova whose explosion kicked its planets out of their orbits and into the Cosmos, and that I am almost certain that many have already read my hypothesis, I will not take the effort and time to post it here.

But wrt the Spokes of Saturn, whatever it is and whatever is causing it will eventually be revealed by the latest telescopic technology, I am certain.
I do believe that 'filaments' exist and that those filaments may have carried electric currents that are surrounded by an electromagnetic field, just as house currents also carry. I hope that it will be found to be so.

Oct 08, 2018
You are completely unaware that you post inanities each time that you include ad hominem, invectives and unfounded accusations in the majority of your posts, while you believe that your incivility is self-correcting just because............Yada, yada, yada.


So, you cannot find anything that I have said that is not backed up by real science? Thought not.
On another note, I'm off to Monkey World tomorrow. Would you like me to obtain some chimpanzee crap, and mail it to you? You can source your own clay, and then proceed to create little SEU clones. Let me know.

says slimeboy jones

The monkeyshit is exclusively yours, as my ancestors were created from clean and pristine clay from a river delta where only animal skin cells had come in contact with. YOU claim that your ancestry descends from chimpanzees and other primates. MY ancestry has nothing to do with that type of descent other than shared DNA - and I have evidence to prove my assertions.

Oct 08, 2018
MY ancestry has nothing to do with that type of descent other than shared DNA - and I have evidence to prove my assertions.


No you don't. You just made up some idiotic woo, and are spamming it on here.


Oct 08, 2018
Oh yes I DO.

Oh here's something for you to read. Read the comments too. Your friend has jealousy written all over its posts.

https://phys.org/...als.html

Oct 08, 2018
Oh yes I DO.

Oh here's something for you to read. Read the comments too. Your friend has jealousy written all over its posts.

https://phys.org/...als.html


And how is that evidence for your idiocy??????

Oct 08, 2018
Oh yes I DO.

Oh here's something for you to read. Read the comments too. Your friend has jealousy written all over its posts.

https://phys.org/...als.html


And how is that evidence for your idiocy??????


What idiocy?????? The link I offered has to do with 3 intrepid researchers who have proven that many publishers of scientific journals are too complacent and lazy to investigate the stories submitted to them for publication, and that they are prone to publishing research results that are phony pieces of crap that often fool the reading public.

Oct 08, 2018
Oh yes I DO.

Oh here's something for you to read. Read the comments too. Your friend has jealousy written all over its posts.

https://phys.org/...als.html


And how is that evidence for your idiocy??????


What idiocy?????? The link I offered has to do with 3 intrepid researchers who have proven that many publishers of scientific journals are too complacent and lazy to investigate the stories submitted to them for publication, and that they are prone to publishing research results that are phony pieces of crap that often fool the reading public.


And how is that evidence for your idiocy? Where was that crap published?

Oct 08, 2018
publishers of scientific journals are too complacent and lazy to investigate the stories submitted to them for publication, and that they are prone to publishing research results that are phony pieces of crap that often fool the reading public.

Yep, see just about anything published on DM, BH, DE, and most other pop-sci-fi claptrap that has pervaded these rags for decades now. Many of the publications produce no science whatsoever.

Oct 08, 2018
publishers of scientific journals are too complacent and lazy to investigate the stories submitted to them for publication, and that they are prone to publishing research results that are phony pieces of crap that often fool the reading public.

Yep, see just about anything published on DM, BH, DE, and most other pop-sci-fi claptrap that has pervaded these rags for decades now. Many of the publications produce no science whatsoever.


Says a cultist who believes Earth used to orbit Saturn! Which was a brown dwarf at the time! Probably about the same time that Venus came flying out of Jupiter, and proceeded to do handbrake turns around the solar system! Yep, very believable. If you possess the IQ of a brain damaged trilobite.

Oct 08, 2018
@jones
That seems to be your claim to fame - that of having the damaged brain of a male gorilla and a female chimp in heat. And so you have descended from such an illustrious family of monkeyshines and barrel-chested gorillas who eat bananas all day long.
So make sure that you run to the store on your knuckles and bring home your stash of bananas for the week - else your mum will box your ears - and rightly so.

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