Saturn Archives

December 5, 2013December 23, 2015 by Elizabeth Howell

Saturn’s Mysterious Hexagon Behaves Like Earth’s Ozone Hole

At Saturn, NASA's Cassini spacecraft snapped pictures showing a high-resolution view of a hexagon-shaped jet stream. Credit: NASA/JPL-Caltech/SSI/Hampton

A raging hurricane is creating a “suck zone” at Saturn’s north pole. The handy Cassini spacecraft recently captured a bunch of images of the six-sided jet stream surrounding the storm, which mission managers then put together into an awesome animation showing the wind currents shifting. (You can see the animation below the jump.)

The feature is pretty in a picture, but NASA has a special interest because there is nothing else like this anywhere in our solar system, the agency stated. The immense storm stretches 20,000 miles (30,000 kilometers) across with winds whipping in its jet stream at 200 miles per hour (322 kilometers per hour). And despite all the turbulence, the storm is staying put at the north pole for reasons scientists are still trying to understand.

“The hexagon is just a current of air, and weather features out there that share similarities to this are notoriously turbulent and unstable,” said Andrew Ingersoll, a Cassini imaging team member at the California Institute of Technology in Pasadena. “A hurricane on Earth typically lasts a week, but this has been here for decades — and who knows — maybe centuries.”

An animation of Cassini Saturn images showing a hexagonal jet stream surrounding a storm at the north pole. Credit: NASA/JPL-Caltech/SSI/Hampton University

Cassini has been orbiting Saturn since 2004, but it’s only since last year that it’s been able to peer at the hexagon with much success. That’s because the angle of the sun is finally favorable to peer at the storm. This has allowed scientists, for example, to look at the types of particles inside. They discovered that the jet stream is a sort of barrier around the storm, delineating a location with a lot of small haze particles and few large haze particles. (It’s the opposite outside of the jet stream). Scientists said it looks like the Antarctic ozone hole on Earth.

“The Antarctic ozone hole forms within a region enclosed by a jet stream with similarities to the hexagon,” NASA stated.

“Wintertime conditions enable ozone-destroying chemical processes to occur, and the jet stream prevents a resupply of ozone from the outside. At Saturn, large aerosols cannot cross into the hexagonal jet stream from outside, and large aerosol particles are created when sunlight shines on the atmosphere. Only recently, with the start of Saturn’s northern spring in August 2009, did sunlight begin bathing the planet’s northern hemisphere.”

Should Cassini have enough funding to function for a few more years, scientists are eager to watch as Saturn gets to its summer solstice in 2017 and the lighting gets even better around the north pole.

NASA also held an interesting Google+ Hangout yesterday (Nov. 4) about Saturn and the Cassini mission that featured Carolyn Porco, director of the Cassini Imaging Team and the Cassini Imaging Central Laboratory for Operations (CICLOPS). The whole video below is worth a watch, but here’s a little tidbit to let you know some of what was talked about:

“If you took all the mass of Saturn’s rings and recomposed it into a moon, it would be no bigger than Enceladus, so it’s a big spectacle coming from little mass,” Porco said. “The main rings are very thin, only about 30 feet [9 meters] thick, no bigger than about 2 stories in a modern day building. Despite the fact they are about 280,000 km [174,000 miles] across.”

December 3, 2013December 23, 2015 by Elizabeth Howell

Ghostly Pic Of Saturn’s Moon Shows It Rising From The Deep

Titan imaged by the Cassini spacecraft. Credit: NASA/JPL-Caltech/Space Science Institute

Sunlight can do fun things in space. For example: this recent picture of Titan (a moon of Saturn) shows sunlight hitting the moon’s surface as well as a southern vortex, just visible in the shadows of the picture.

“The sunlit edge of Titan’s south polar vortex stands out distinctly against the darkness of the moon’s unilluminated hazy atmosphere,” NASA stated. “The Cassini spacecraft images of the vortex led scientists to conclude that its clouds form at a much higher altitude — where sunlight can still reach — than the surrounding haze.”

Titan has intrigued scientists for decades, since the Voyager spacecraft first revealed it as a world socked in by orange haze. Cassini dropped off a lander on the surface, called Huygens, which took pictures on the surface in 2005. Besides that, the orbiter has revealed a lot about lakes, rain and other features of the moon in the year since.

Cassini has been orbiting the moon since 2004 and is still busily producing science, but there are concerns that NASA’s budget situation could cause the agency to shut down operations on the still-healthy spacecraft. There are no other missions to Saturn or Titan booked yet, although scientists do have intriguing ideas for exploration.

November 12, 2013December 23, 2015 by Jason Major

The Day the Earth Smiled: Saturn Shines in this Amazing Image from the Cassini Team

The "pale blue dot" of Earth as seen from Cassini on July 19, 2013.

This summer, for the first time ever, the world was informed that its picture was going to be taken from nearly a billion miles away as the Cassini spacecraft captured images of Saturn in eclipse on July 19. On that day we were asked to take a moment and smile and wave at Saturn, from wherever we were, because the faint light from our planet would be captured by Cassini’s camera, shielded by Saturn from the harsh glare of the Sun.

A few preliminary images were released just a few days later showing the “pale blue dot” of Earth nestled within the glowing bands of Saturn’s rings. It was an amazing perspective of our planet, and we were promised that the full mosaic of Cassini images was being worked on and would be revealed in the fall.

Well, it’s fall, and here it is:

The full mosaic from the Cassini imaging team of Saturn on July 19, 2013... the "Day the Earth Smiled" — The full mosaic from the Cassini imaging team of Saturn on July 19, 2013… the “Day the Earth Smiled”

Simply beautiful!

Cassini Imaging Team leader Carolyn Porco wrote on her Facebook page:

“After much work, the mosaic that marks that moment the inhabitants of Earth looked up and smiled at the sheer joy of being alive is finally here. In its combination of beauty and meaning, it is perhaps the most unusual image ever taken in the history of the space program.”

Download a full-size version here.

Earth and Moon seen by Cassini on July 19, 2013

In this panorama of the Saturnian system, a view spanning 404,880 miles (651,591 km), we see the planet silhouetted against the light from the Sun. It’s a unique perspective that highlights the icy, reflective particles that make up its majestic rings and also allows our own planet to be seen, over 900 million miles distant. And it’s not just Earth that was captured, but the Moon, Venus, and Mars were caught in the shot too.

According to the description on the CICLOPS page, “Earth’s twin, Venus, appears as a bright white dot in the upper left quadrant of the mosaic… between the G and E rings. Mars also appears as a faint red dot embedded in the outer edge of the E ring, above and to the left of Venus.”

This was no simple point-and-click. Over 320 images were captured by Cassini on July 19 over a period of four hours, and this mosaic was assembled from 141 of those images. Because the spacecraft, Saturn, and its moons were all in constant motion during that time, affecting not only positions but also levels of illumination, imaging specialists had to adjust for that to create the single image you see above. So while all elements may not be precisely where they were at the same moment in time, the final result is no less stunning.

“This version was processed for balance and beauty,” it says in the description. (And I’ve no argument with that.)

See below for an annotated version showing the position of all visible objects, and read the full article on the CICLOPS page for an in-depth description of this gorgeous and historic image.

“I hope long into the future, when people look again at this image, they will recall the moment when, as crazy as it might have seemed, they were there, they were aware, and they smiled.”

–Carolyn Porco, Cassini Imaging Team Leader

Also, check out another version of this image from NASA made up of submitted photos from people waving at Saturn from all over the world. (Full NASA press release here.)

All images credit NASA/JPL-Caltech/Space Science Institute

UPDATE 11/13: CICLOPS Director Carolyn Porco describes how this image was acquired and assembled in this interview video from the World Science Festival:

November 5, 2013December 23, 2015 by Elizabeth Howell

Five Saturn Moons Stun In Cassini Spacecraft Archival Image

Saturn's moons (from left to right) Janus, Pandora, Enceladus, Mimas and Rhea. Rhea is on top of Saturn. Credit: NASA/JPL-Caltech/Space Science Institute

This picture is from a couple of years ago, but still worth the extra look. The Cassini spacecraft — busily circling Saturn and gathering data on the ringed planet and its moons — managed to grab five of Saturn’s 62 known moons in one shot. The European Space Agency highlighted the picture on its home page this week.

From left to right, you can see Janus, Pandora, Enceladus, Mimas and Rhea. Don’t be fooled by the rings near Rhea; those are actually Saturn’s rings. Rhea is just blocking the view of the planet from Saturn’s perspective during this picture portrait, which was taken on July 29, 2011.

The cornucopia of moons around Saturn is part of what makes that particular planet so interesting. Titan, the largest, is perhaps the most well-known because of its strange orange haze that intrigued astronomers when the twin Voyager spacecraft zoomed through the system in the 1980s. Cassini arrived in 2004 and revealed many more moons to science for the first time.

Color-composite of Titan made from raw Cassini images acquired on April 13, 2013 (added 4/17) NASA/JPL/SSI. Composite by J. Major.

“The dozens of icy moons orbiting Saturn vary drastically in shape, size, surface age and origin. Some of these worlds have hard, rough surfaces, while others are porous bodies coated in a fine blanket of icy particles. All have greater or smaller numbers of craters, and many have ridges and valleys,” NASA wrote on a web page about Saturn’s moons.

“Some, like Dione and Tethys, show evidence of tectonic activity, where forces from within ripped apart their surfaces. Many, like Rhea and Tethys, appear to have formed billions of years ago, while others, like Janus and Epimetheus, could have originally been part of larger bodies that broke up. The study and comparison of these moons tells us a great deal about the history of the Saturn System and of the solar system at large.”

And new discoveries are coming out all the time. Earlier this year, for example, astronomers said that the moon Dione could have had active geysers coming from its surface, such as what is likely happening on Enceladus.

October 17, 2013December 23, 2015 by Nancy Atkinson

An Incredible View of Saturn that Could Only Be Seen by a Visiting Spacecraft

Saturn and its rings, as seen from above the planet by the Cassini spacecraft. Credit: NASA/JPL/Space Science Institute. Assembled by Gordan Ugarkovic. — Saturn and its rings, as seen from above the planet by the Cassini spacecraft. Credit: NASA/JPL/Space Science Institute/Gordan Ugarkovic

So what did NASA do during the US government shutdown? You can’t just turn off spacecraft that are operating millions of miles away, so missions like the Mars rovers and the Cassini spacecraft at Saturn continued to send back images to Earth during the 16 days that most of NASA wasn’t up and running like usual. On October 10, 2013, as Cassini flew high above the planet’s equatorial plane, the spacecraft’s camera took 36 images of Saturn, a dozen each using the various red, green, and blue filters used to create color images. The images were transferred back to Earth and put on the Cassini raw images page. Gordan Ugarkovic from Croatia, and a member of the image editing wizards at UnmannedSpaceflight.com, grabbed the raw files, processed them, then assembled the images into this jaw-dropping mosaic.

This is a view from Saturn that we could never get from Earth; only a spacecraft orbiting the planet could take it. You can see the north pole and the swirling maelstrom of clouds that creates the hexagonal polar vortex, the thin bands in Saturn’s atmosphere, and — of course — what really stands out is the incredible view of Saturn’s rings. To see the original 3 MB version, see this page on UMSF.

“You shouldn’t be surprised to see processing artifacts here and there,” cautioned Ugarkovic via email to Universe Today. “It is, after all, based on raw JPEG images only.”

See more of Gordan’s work at his Flickr page.

You can read more details about this from Emily Lakdawalla at the Planetary Society, or Phil Plait at Bad Astronomy/Slate.

But in the words of UMSF’s Astro0, “That’s the sort of view I’ve dreamed I would only ever see in a science fiction movie or if we had some kind of amazing futuristic spacecraft orbiting around that distant ringed planet….WAIT! We do!”

For more of what NASA did during the shutdown, Bill Dunford at Riding With Robots put together a great summary, quoting the @SarcasticRover that “You can’t shut down awesome.” Bill started the #ThingsNASAMightTweet hashtag that reminded everyone of all the things NASA does, but they couldn’t tweet about during the shutdown. People from around the world chimed in, adding what was important to them about NASA, and as of today, tweets with that hashtag have passed 27 million impressions.

October 10, 2013December 23, 2015 by Tammy Plotner

Jupiter And Saturn May Be Rich In Diamonds

“Picture yourself in a boat on a river…” And make it a river of liquid hydrogen and helium deep within the atmospheres of Jupiter and Saturn. You might not find a girl with kaleidoscope eyes, but you may very well find diamonds. According to new research, there may be an abundance of these precious gemstones swirling about in the skies of our solar system’s giant planets.

Recent data compiled by planetary scientists Mona L. Delitsky of California Specialty Engineering in Pasadena, California, and Kevin H. Baines of the University of Wisconsin-Madison, has been combined with newly published pressure temperature diagrams of Jupiter and Saturn. These diagrams, known as adiabats, allow researchers to decipher at what interior level that diamond would become stable. They also allow for calculations at lower levels – regions where both temperature and pressure are so concentrated that diamond becomes a liquid. Imagine diamond rain… or rivulets of pure gemstone.

These adiabats of Saturn and Jupiter’s interior materials have been improved through new equations. Through the use of shockwave techniques, researchers at Sandia Laboratories and Lawrence Livermore National Laboratory have been provided with set boundaries for the various states of carbon. From these findings, you would be amazed at the chain of events at what might make diamonds occur. According to Delitsky and Baines, carbon could be generated as soot or graphite from a lightning strike. Since lightning is normal during Saturn’s many huge electrical storms, it stands to reason this elemental carbon would descend to a lower atmospheric level to be compressed into solid diamonds. It would then further descend towards the planet’s core to be eventually “pressure cooked” into a liquid state.

While the idea of diamonds at the heart of planets like Uranus and Neptune has been known for at least three decades, planetary scientists have been hesitant to include Jupiter and Saturn, concluding they were either too cool, too hot, or otherwise not suitable for the production of solid diamonds. Just as Jupiter and Saturn are much warmer at their cores, Uranus and Neptune are much too cold to sustain diamonds in a liquid state. However, thanks to the latest data, researchers are confident that deep inside Saturn there may be diamonds so large that they could be referred to as “diamondbergs”!

Is this the kind of stuff we dream of one day mining? You bet. In a book entitled “Alien Seas” (Springer 2013), Baines and Delitsky have devoted a chapter to the ringed planet entitled “The Seas of Saturn”. Here the duo elucidates on the new, accurate data and makes up a story about robotic mining missions delving deep into the interior of Saturn. Spooky robot hands reach out through the mist, gathering chunks of diamonds and ready them for return to Earth. Because of this new information, theorists Delitsky and Baines report that “diamonds are forever on Uranus and Neptune and not on Jupiter and Saturn.”

Ah, well… I’m still watching for Lucy in the sky.

This news release is based on DPS abstract #512.09 by M. L. Delitsky and K. H. Baines for their conference oral talk on Friday, 11 October 2013.

September 17, 2013December 23, 2015 by Jason Major

A “Mini Jet” Juts from Saturn’s F Ring

A bright "mini-jet" spotted in Saturn's F ring

We all know that Saturn’s moon Enceladus has a whole arsenal of geysers jetting a constant spray of ice out into orbit (and if you didn’t know, learn about it here) but Enceladus isn’t the only place in the Saturnian system where jets can be found — there are some miniature versions hiding out in the thin F ring as well!

Watch the 50-mile-wide Prometheus dip into the F ring (CLICK TO PLAY) NASA/JPL/SSI. Animation by J. Major.

The image above, captured by the Cassini spacecraft on June 20, 2013, shows a segment of the thin, ropy F ring that encircles Saturn just beyond the A ring (visible at upper right). The bright barb near the center is what scientists call a mini jet, thought to be caused by small objects getting dragged through the ring material as a result of repeated passings by the shepherd moon Prometheus.

Coincidentally, it’s gravitational perturbations by Prometheus that help form the objects — half-mile-wide snowball-like clusters of icy ring particles — in the first place.

Unlike the dramatic jets on Enceladus, which are powered by tidal stresses that flex the moon’s crust, these mini jets are much more subtle and occur at the casual rate of 4 mph (2 meters/second)… about the speed of a brisk walk.

The reflective jets themselves can be anywhere from 25 to 112 miles (40 to 180 kilometers) long.

See more images of mini jets — also called “classic trails” — below:

Various images of mini jets captured by Cassini from 2005 to 2008.

Over 500 of these features have been imaged by Cassini since 2005. Read more about mini jets here.

(And don’t worry, Enceladus… these little jets are interesting but they have nothing on you!)

Source: Cassini Imaging Central Laboratory for OPerationS (CICLOPS)

Image credits: NASA/JPL-Caltech/SSI/QMUL.

September 16, 2013April 26, 2016 by Elizabeth Howell

Ice Volcanoes Likely Alter Titan’s Surface Brightness: Study

Titan peeks from behind two of Saturn's rings. Another small moon Epimetheus, appears just above the rings. Credit: NASA/JPL/Space Science Institute

Icy volcanoes are likely responsible for changes in brightness on the surface of Titan, the largest moon of Saturn, according to a new study.

Images with the Cassini spacecraft’s visual and infrared mapping spectrometer revealed the brightness, or albedo, of two equatorial areas changing during the study period. Tui Regio (which got darker from 2005 to 2009) and Sotra Patera (which got brighter from 2005 to 2006).

The researchers also pointed to “volcanic-like features” in these areas as evidence that the potential cryovolcanoes, as these icy volcanoes are known, might be connected to an ocean on Titan.

Top: Sotra Patera, a cryovolcanic candidate on Titan that has a one-kilometer crater. (Credit: NASA/JPL Caltech/USGS/University of Arizona). Bottom: The Kirishima volcano in Japan, a terrestrial analogue (Credit: USGS).

“All of these features, plus a need for a methane reservoir and volcanic activity to replenish the methane in the atmosphere, is compatible with the theory of active cryovolcanism on Titan,” stated Anezina Solomonidou , a planetary geologist with the Paris Observatory as well as the National and Kapodistrian University of Athens.

“These results have important implications for Titan’s potential to support life, as these cryovolcanic areas might contain environments that could harbor conditions favorable for life,” Solomonidou added.

Of note, Titan also has a fresh-looking surface with few craters on it, indicating that something might be altering the surface. “Its landscape is remarkably Earth-like with dunes and lakes, erosion due to weathering and tectonic-like features,” a statement on the research added.

There’s been chatter about cryovolcanoes on Titan before. In 2010, researchers said a chain of peaks found on the moon could be evidence of this type of feature. However, a 2012 preliminary California Institute of Technology weather model of the moon explained many of its features without necessarily needing to rely on cryovolcanoes.

Source: European Planetary Science Congress

September 13, 2013December 23, 2015 by Elizabeth Howell

10 Historic Moments in Voyager’s Journey to Interstellar Space

The Voyager spacecraft have been on an extensive mission of discovery that has lasted some 36 years. Image Credit: NASA/JPL

Yesterday, NASA announced that as of August 2012, Voyager 1 is in a new frontier to humanity: interstellar space. Our most distant spacecraft is now in a region where the plasma (really hot gas) environment comes more from between the stars than from the sun itself. (There’s still debate as to whether it’s in or out of the solar system, as this article explains.)

The plucky spacecraft is close to 12 billion miles (19 million kilometers) from home, and in its 36 years of voyaging has taught us a lot about the planets, their moons and other parts of space. Here are 10 of some of its most historic moments. Did we miss any? Let us know in the comments.

10. The launch: Aug. 20, 1977

Voyager 1 launches from the Kennedy Space Center on Sept. 5, 1977. Credit: NASA

Voyager 1 blasted off from Cape Canaveral on Sept. 5, 1977. Its twin, Voyager 2, departed Earth 16 days earlier. Each spacecraft carried various scientific instruments on board as well as a “Golden Record” that had sounds of Earth on it, as well as a diagram showing where Earth is in the universe.

9. Capturing the Earth and Moon together for the first time

On Sept. 18, 1977, Voyager 1 took three images of the Earth and Moon that were combined into this one image. The moon is artificially brightened to make it show up better. Credit: NASA

About two weeks after launching, Voyager 1 turned back towards Earth and took three images, which were combined into this single view of the Earth and Moon together in space. This was the first time both bodies were pictured together, NASA said.

8. The ‘Pale Blue Dot’ image

Voyager 1 pale blue dot. Image credit: NASA/JPL

On February 14, 1990, Voyager 1 was about 3.7 billion miles (6 billion kilometers) away from Earth. Scientists commanded the spacecraft to turn its face towards the solar system and snap some pictures of the planets. Among them was this famous image of Earth, which astronomer Carl Sagan called the Pale Blue Dot. “Look again at that dot. That’s here. That’s home. That’s us,” wrote Sagan in his 1997 book of the same name. In 2013, the spacecraft Cassini also took a picture of Earth, and NASA encouraged everyone to wave back.

7. Finding moons “shepherding” Saturn’s F ring

Prometheus, a small potato-shaped moon of Saturn, shown in this Voyager 1 picture interacting with the planet's F ring. Credit: NASA/JPL/SSI — Prometheus, a small potato-shaped moon of Saturn, shown in this Voyager 1 picture interacting with the planet’s F ring. Credit: NASA/JPL/SSI

Voyager 1 spotted Prometheus and Pandora, two moons of Saturn that keep the F ring separate from the rest of the debris, as well as Atlas, which “shepherds” the A ring. More recently, astronomers have found even more interesting things in Saturn’s rings — such as rain.

6. Spotting what appeared to be a LOT of water ice on Saturn’s moons

Encaladus, a moon of Saturn, as shown in this Voyager 1 image. Credit: NASA

After many years of seeing Saturn’s moons as mere points of light, Voyager 1 buzzed several of them in its quick flyby through the system: Dione, Enceladus, Mimas, Rhea, Tethys and Titan among them. Many of these moons appeared to be icy, which was a surprising find since astronomers previously thought water was pretty rare in the Solar System. We know better now.

5. Imaging Titan’s orange haze

Saturn's moon Titan lies under a thick blanket of orange haze in this Voyager 1 picture. Credit: NASA — Saturn’s moon Titan lies under a thick blanket of orange haze in this Voyager 1 picture. Credit: NASA

Voyager 1 pictures such as this tortured astronomers for decades — what lies beneath this mysterious haze surrounding Titan, Saturn’s moon? That mystery, in fact, inspired the European Space Agency to send a lander to the moon, called Huygens, which successfully reached the surface in 2005.

4. Finding active volcanoes on Io

Io's blotchy volcanoes are clearly visible in this image from Voyager 1. Credit: NASA — Io’s blotchy volcanoes are clearly visible in this image from Voyager 1. Credit: NASA

Voyager 1 helped show us that the Solar System is full of very interesting moons. At Io — a moon of Jupiter — it turns out the moon flexes during its 42-hour orbit of massive Jupiter, which powers a lot of volcanic activity.

3. Voyager 1 becomes the most distant human object

A 2013 snapshot riding along with Voyager 1's looking back at the Sun and inner solar system. The positions of Voyager 2 and Pioneers 10 and 11 show within the viewport as well. — A 2013 computer-generated snapshot riding along with Voyager 1’s looking back at the Sun and inner solar system. The positions of Voyager 2 and Pioneers 10 and 11 show within the viewport as well.

On Feb. 17, 1998, Voyager 1’s distance surpassed that of another long-flying probe, Pioneer 10. This made Voyager 1 the farthest-flung human object in space.

2. Riding the “magnetic highway”

Artist concept of NASA’s Voyager 1 spacecraft exploring a new region in our solar system called the “magnetic highway.” Credit: NASA/JPL-Caltech

In December, NASA said Voyager 1 had reached an area (as of July 28, 2012) where high-energy magnetic particles were starting to bleed through the bubble of lower-energy particles from our sun. “Voyager’s discovered a new region of the heliosphere that we had not realized was there. It’s a magnetic highway where the magnetic field of the Sun is connected to the outside. So it’s like a highway, letting particles in and out,” said project scientist Ed Stone at the time. After that point, as more measurements were analyzed by different teams, there was a lot of debate as to whether Voyager had reached interstellar space.

1. Reaching interstellar space

This graphic shows the main evidence that Voyager 1 has reached interstellar space. The blue line shows particle density, which dropped as Voyager 1 moved away from the sun, and then jumped again after it crossed the "termination shock" that is where the sun's solar wind (particles streaming from the sun) slows down. Credit: NASA/JPL-Caltech — This graphic shows the main evidence that Voyager 1 has reached interstellar space. The blue line shows particle density, which dropped as Voyager 1 moved away from the sun, and then jumped again after it crossed the “termination shock” that is where the sun’s solar wind (particles streaming from the sun) slows down. Credit: NASA/JPL-Caltech

With Voyager 1 now known to be in interstellar space, we’re lucky enough to have a few years left to communicate with it before it runs out of power. All of the instruments will be turned off by 2025, and then engineering data will be available for about 10 years beyond that. The silent emissary from humanity will then come within 1.7 light years of an obscure star in the constellation Ursa Minor (the Little Bear) called AC+79 3888 in the year 40,272 AD and then orbit the center of the Milky Way for millions of years.

September 3, 2013December 23, 2015 by Nancy Atkinson

Massive Storm Reveals Water Deep Within Saturn’s Atmosphere

This set of images from NASA's Cassini mission shows the turbulent power of a monster Saturn storm. The visible-light image in the back, obtained on Feb. 25, 2011, by Cassini's imaging camera, shows the turbulent clouds churning across the face of Saturn. The inset infrared image, obtained a day earlier, by Cassini's visual and infrared mapping spectrometer, shows the dredging up of water and ammonia ices from deep in Saturn's atmosphere. This was the first time water ice was detected in Saturn's atmosphere. Credit: NASA/JPL-Caltech/SSI/Univ. of Arizona/Univ. of Wisconsin

Remember the huge storm that erupted on Saturn in late 2010? It was one of the largest storms ever observed on the ringed planet, and it was even visible from Earth in amateur-sized telescopes. The latest research has revealed the tempestuous storm churned up something surprising deep within Saturn’s atmosphere: water ice. This is the first detection of water ice on Saturn, observed by the near-infrared instruments on the Cassini spacecraft.

“The new finding from Cassini shows that Saturn can dredge up material from more than 100 miles [160 kilometers],” said Kevin Baines, a co-author of the paper who works at the University of Wisconsin-Madison and NASA’s Jet Propulsion Laboratory, Pasadena, Calif. “It demonstrates in a very real sense that typically demure-looking Saturn can be just as explosive or even more so than typically stormy Jupiter.”

While Saturn’s moons have lots of water ice, Saturn is almost entirely hydrogen and helium, but it does have trace amounts of other chemicals, including water. When we look at Saturn, we’re actually seeing the upper cloud tops of Saturn’s atmosphere, which are made mostly of frozen crystals of ammonia.

Beneath this upper cloud layer, astronomers think there’s a lower cloud deck made of ammonium hydrosulfide and water. Astronomers thought there was water there, but not very much, and certainly not ice.

This series of images from NASA’s Cassini spacecraft shows the development of the largest storm seen on the planet since 1990. These true-color and composite near-true-color views chronicle the storm from its start in late 2010 through mid-2011, showing how the distinct head of the storm quickly grew large but eventually became engulfed by the storm’s tail. Credit: NASA/JPL-Caltech/Space Science Institute

But the storm in 2010-2011 appears to have disrupted the various layers, lofting up water vapor from a lower layer that condensed and froze as it rose. The water ice crystals then appeared to become coated with more volatile materials like ammonium hydrosulfide and ammonia as the temperature decreased with their ascent, the authors said.

“The water could only have risen from below, driven upward by powerful convection originating deep in the atmosphere,” said Lawrence Sromovsky, also of the University of Wisconsin, who lead the research team. “The water vapor condenses and freezes as it rises. It then likely becomes coated with more volatile materials like ammonium hydrosulfide and ammonia as the temperature decreases with their ascent.

Big storms appear in the northern hemisphere of Saturn once every 30 years or so, or roughly once per Saturn year. The first hint of the most recent storm first appeared in data from Cassini’s radio and plasma wave subsystem on Dec. 5, 2010. Soon after that, it could be seen in images from amateur astronomers and from Cassini’s imaging science subsystem. The storm quickly grew to superstorm proportions, encircling the planet at about 30 degrees north latitude for an expanse of nearly 300,000 km (190,000 miles).

The researchers studied the dynamics of this storm, and realized that it worked like the much smaller convective storms on Earth, where air and water vapor are pushed high into the atmosphere, resulting in the towering, billowing clouds of a thunderstorm. The towering clouds in Saturn storms of this type, however, were 10 to 20 times taller and covered a much bigger area. They are also far more violent than an Earth storm, with models predicting vertical winds of more than about 300 mph (500 kilometers per hour) for these rare giant storms.

The storm’s ability to churn up water ice from great depths is evidence of the storm’s explosive power, the team said.

Their research will be published in the Sept. 9 edition of the journal Icarus.

Sources: University of Wisconsin-Madison, JPL