# The science of Enceladus deserves its' own thread



## CAPSLOCKSTUCK (Oct 15, 2015)

Bringing the spacecraft within 1,142 miles (1,839 kilometers) of Enceladus. It was expected to provide the first clear look at the moon's north polar region. The summer sun is shining on Enceladus now, illuminating its northern latitudes and allowing scientists the chance to search for signs of ancient geological activity, according to a NASA statement. The feat was not possible during previous encounters as the region was covered in winter's shadow.

The first flyby is a just warm-up to an exciting main event. On Oct. 28, Cassini is set to pass a mere 30 miles (49 km) above the moon's south polar region. In a daring maneuver, the probe will conduct its deepest dive through the moon's icy plumes. The flyby is scheduled for a time when the plumes will be at their maximum output, enabling the science team to examine their composition.

The first flyby is a just warm-up to an exciting main event. On Oct. 28, Cassini is set to pass a mere 30 miles (49 km) above the moon's south polar region. In a daring maneuver, the probe will conduct its deepest dive through the moon's icy plumes. The flyby is scheduled for a time when the plumes will be at their maximum output, enabling the science team to examine their composition

An icy plume














"We've been following a trail of clues on Enceladus for 10 years now," Cassini science team member Bonnie Buratti, an and icy moons expert at NASA's Jet Propulsion Laboratory in Pasadena, California, said in the same statement. "The amount of activity on and beneath this moon's surface has been a huge surprise to us. We're still trying to figure out what its history has been, and how it came to be this way."

The geysers, along with the presence of a global ocean of water on Enceladus, and evidence of hydrothermal activity — similar to the activity we see on the ocean floor here on Earth — may mean that the Saturn moon is one of the best places in the solar system to search for life beyond our own planet.

"The global nature of Enceladus' ocean and the inference that hydrothermal systems might exist at the ocean's base strengthen the case that this small moon of Saturn may have environments similar to those at the bottom of our own ocean," Jonathan Lunine, an interdisciplinary scientist on the Cassini mission at Cornell University in Ithaca, New York, said in the statement. "It is therefore very tempting to imagine that life could exist in such a habitable realm, a billion miles from our home."

Scientists plan to learn as much as possible during these flybys as they will be the last chances to see Enceladus up close for many years to come.





https://en.wikipedia.org/wiki/Enceladus


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## CAPSLOCKSTUCK (Oct 16, 2015)

Blurry images captured by Nasa's Voyager mission suggested the Enceladus' north pole was heavily cratered, but these latest high-resolution shots show instead just how varied the landscape is.

Taken by the Cassini spacecraft as it made its 14 October flyby, the images show the northern regions are covered in cracks that slice through the craters on one side, while the other side appears much smoother.

Nasa captured the best ever views of the northern extremes of Saturn's icy, ocean-bearing moon as it travelled 1,142 miles (1,839km) above the lunar surface.





The images were captured by Nasa's Cassini spacecraft during its 14 October flyby of Saturn's icy moon Enceladus. Cassini passed 1,142 miles (1,839km) above the surface. This show images show the northern regions of the moon covered in cracks that slice through the craters on one side, while the other side appears much smoother


The first image shows the curvature of the moon and the pockmarks created by the craters. A second image zooms in closer to this surface to show the cracks that tear through these craters.

One large crack resembles a river running through the centre of this northern region.
Cracks have similarly been spotted in the surface of our own moon and this has been blamed on the gravitational pull of Earth tearing its surface apart.


In fact, Nasa scientists have identified more than 3,200 cracks, each several miles long and dozens of feet deep, crisscrossing our moon's surface that resemble those spotted on Enceladus.





A second image zooms in closer to this surface to show the cracks (pictured) that tear through these craters. The long crack in this image resembles a river running through the centre of this northern region. Cracks have similarly been spotted in the surface of our own moon and this has been blamed on the gravitational pull of Earth tearing its surface apart





Nasa's Cassini spacecraft spied the tight trio of craters (above) as it approached Enceladus earlier this week and has dubbed it the 'Saturnian snowman'. The craters, spotted at high northern latitudes, are sliced through by thin fractures and are part of a network of similar cracks that wrap around the moon. The bottom image shows one of these fractures in greater detail





'The northern regions are crisscrossed by a spidery network of gossamer-thin cracks that slice through the craters,' said Paul Helfenstein, a member of the Cassini imaging team at Cornell University, New York.'These thin cracks are ubiquitous on Enceladus, and now we see that they extend across the northern terrains as well.'

In another image, Cassini spied a tight trio of craters as it made its approach to the icy moon.The craters, located at high northern latitudes, are sliced through by thin fractures that form part of the network of similar cracks that wrap around the moon.Nasa has dubbed the trio of craters 'Saturnian snowman' because of its shape.

That particular image was taken in visible light using a narrow-angle camera at a distance of approximately 6,000 miles (10,000 km) from Enceladus.

To give an indication of the size of the 310-mile (500km) wide moon, the image scale is 197ft (60 metres) per pixel.


Enceladus is Saturn's sixth-largest moon - one of 62 - discovered in 1789 by William Herschel.

In the early 1980s Nasa sent two Voyager spacecraft to the Saturnian system to capture the first close-up images of the moon.

Voyager 1 made its flyby on 12 November 1980 but captured only poor resolution shots that revealed a highly reflective surface that didn't appear to have any craters on it.

Voyager 2 made its closest approach on 26 August 1981 during which its higher-resolution images instead revealed the surface to be heavily cratered in the north and lightly cratered around the equator.

Nasa's Cassini craft began multiple flybys of Enceladus in 2005 and was able to identify cryovolcanoes near the south pole that shoot geyser-like jets of water vapour.

Last month, these geysers were said to be evidence of a large ocean beneath Enceladus' surface.

Nasa said the fine spray of water vapour, icy particles and simple organic molecules Cassini had observed coming from fractures near the moon's south pole are fed by a vast liquid water reservoir.












Last month, the geysers were said to be evidence of a large ocean beneath Enceladus' surface (illustrated). Nasa said the fine spray of water vapour, icy particles and simple organic molecules Cassini had observed coming from fractures are fed by a liquid water reservoir

This also explains why the moon has a very slight wobble as it orbits Saturn. Without a solid core, the moon travels slightly faster and slower during different portions of its orbit which causes it to rock back and forth.This is enhanced by the fact Enceladus isn't a perfect sphere.

Images released last month also revealed that Enceladus is slowly being eaten up by its host planet's giant's rings.These images showed how long, sinuous, tendril-like structures near Enceladus are transferring material from the moon into Saturn's rings.These ghostly tendrils have long been known to follow Enceladus in its orbit around the gas giant and the images provided scientists with the first opportunity to track their source.The tendrils reach into Saturn's E ring - the ring in which Enceladus orbits - extending tens of thousands of miles away from the moon.


Cassini's next encounter with Enceladus is planned for 28 October when the spacecraft will come within 30 miles (49km) of the moon's south polar region.

During the encounter, Cassini will make its deepest-ever dive through the moon's plume of icy spray to sample the chemistry of the extraterrestrial ocean beneath the ice.

Mission scientists said they are hopeful data from that flyby will provide evidence of how much hydrothermal activity is occurring in the moon's ocean, along with more detailed insights about the ocean's chemistry - both of which relate to the potential for Enceladus to host life.

Cassini will then make its final close Enceladus flyby on 19 December when the spacecraft will measure the amount of heat coming from the moon's interior. That flyby will be at an altitude of 3,106 miles (4,999km).


The Cassini-Huygens mission is a cooperative project between Nasa, Esa and the Italian Space Agency.


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## CAPSLOCKSTUCK (Oct 16, 2015)

this warrants its' own post rather than an edit to a previous one......i hope you agree


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## jboydgolfer (Oct 16, 2015)

mmmmmm.....enchilada's ... i love mexican food...see what i did there..very clever.


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## CAPSLOCKSTUCK (Oct 16, 2015)

Some mods like jumping on science stuff and * it is tech* as far as many of us think, we grew  up dreaming about and loving this stuff long before microchips were even first baked up

so please, i know its funny but its not long before people jump on the bandwagon and soon something thats ace gets thrown into GN and never heard of again when it is genuine tech and it is genuine science which is of a lot of interest to a large part of the community.

False colour Cassini image illustrating the jets of fine icy particles erupting from the south polar region of Enceladus





I am going for a lie down now


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## CAPSLOCKSTUCK (Oct 17, 2015)

Cassini will perform another fly-by of Enceladus later this month when it will swoop to within just 30 miles of the south pole.









A beautiful view of the night side of a crescent Enceladus, lovingly lit by Saturnshine. This was captured by the Cassini spacecraft during a close pass on Oct. 14, 2015. The 6.5-mile-wide Bahman cater is visible near the center. Credit: NASA/JPL-Caltech/Space Science Institute, image editing by Jason Major.






I just cant believe how beautiful this one is







Global 3d colour map of Enceladus


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## CAPSLOCKSTUCK (Oct 17, 2015)

i am about to double post with this monumental picture, if it breaks the rules i will happlily delete it, however, i have a shit memory and there is a very good chance that i will forget to repost it, so for the sake of humanity and space exploration and education i am posting it now in case i forget tomorrow


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## CAPSLOCKSTUCK (Oct 18, 2015)

Average orbital distance: 147,909 miles (238,037 km)
Closest orbit: 147,214 miles (236,918 km)
Farthest orbit: 1486,605 miles (239,156 km)
Orbital period: 1.37 Earth-days
Orbital velocity: 28,265 mph (45,487.3 kph)
Orbit eccentricity: 0.0047
Mean Radius: 156.6 miles (252.1 km)
Equatorial Circumference: 929,336 miles (1,495,622 km)
Surface Gravity: 0.113 m/s2
Escape velocity: 353 mph (861 kph)










Enceladus was first studied in detail by the Voyager spacecraft. The Cassini mission did close flybys of this moon, to map its surface in high resolution.
Enceladus is a largely icy world with some percentage of its mass being silicates. It appears to have a rocky core mixed with with water ice, and a frozen mantle.
Cryovolcanic activity in Enceladus is sending geysers of water ice particles out from underneath the surface. The Cassini spacecraft has imaged these geysers spouting from so-called “tiger stripes” vent areas on this moon.
The icy particles from Enceladus spread out to space and feed the nearby E-ring with material.
The volcanic action on Enceladus led scientists to suggest that a liquid water ocean lies under the surface of this moon, and is feeding the geysers seen by Cassini.
Enceladus is thought to be heated from within by either radioactive heating (the decay of radioactive elements in the core) or tidal flexing as Saturn’s immense gravity pulls on the moon.
Future missions have been proposed to explore Enceladus and perhaps bring back samples of its icy plume material. These would also study the other moons of Saturn, plus the ring system.
As with Europa at Jupiter, scientists suspect that Enceladus could be a habitable world to some forms of life. There is no proof of life there, but future missions could test for life signs.
Enceladus is now known to have a subsurface ocean made of liquid water. Images from the Cassini spacecraft helped mission scientists deduce and prove the existence of that ocean.




















Us, our Moon and Enceledus
	

	
	
		
		

		
		
	


	






Enceladus/Distance to Earth

1.272 billion km


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## Drone (Oct 18, 2015)

Enceladus ... in the lower left






Enceladus's snowman






Warm fractures


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## CAPSLOCKSTUCK (Oct 18, 2015)

Plumes of water ice spewing from the south polar region of Saturn’s moon Enceladus. The image was taken in visible light with the Cassini spacecraft narrow-angle camera
http://www.ciclops.org/iss/iss.php?js=1











View of Enceladus from Voyager 2, showing crater-free portions of the surface, possibly indicative of resurfacing by liquid water from the interior.






Hubble Space Telescope image of Saturn and several of its moons. At the north pole, the shadow of Titan is visible; below it is Mimas. Dione and Enceladus are faintly visible at left, off the planet’s rings.


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## CAPSLOCKSTUCK (Oct 19, 2015)

This raw, unprocessed image of Enceladus was taken by NASA's Cassini probe, Bright plumes of water vapour are visible on the moon's south pole.







A new image of Saturn's moon Enceladus backlit by the Sun show the fountain-like sources of the fine spray of material that towers over the south polar region. The image is greatly enhanced and colorized






Three of Saturn's moons appear in a somber group portrait along with the northern, sunlit ringplane. Rhea (949 miles or 1,528 kilometers across) is closest to Cassini spacecraft, which took the photograph, and appears largest at the center of the image. Enceladus (313 miles or 504 kilometers across) is to the right of Rhea. Dione (698 miles or 1,123 kilometers across) is to the left of Rhea, partly obscured by Saturn. Saturn is present on the left of this image but its night side is too dark to see. 





This photo, taken by NASA's Cassini spacecraft on July 29, 2011, shows Saturn's A and F rings and five of its moons. From left, the moons are Janus, Pandora, Enceladus, Mimas and Rhea.






Saturn’s icy moon Enceladus hangs below the gas giant’s rings while Titan lurks in the background, in this new image taken by the Cassini spacecraft on March 12, 2012.


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## Drone (Oct 21, 2015)

to scale















new images


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## Drone (Oct 21, 2015)

part 2


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## Drone (Oct 26, 2015)

new image






lots of things coming in 2 todays


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## CAPSLOCKSTUCK (Oct 26, 2015)

Is there life on Enceladus? Probe hoping to unlock the secrets of Saturn's moon will travel through its icy spray on Wednesday







The surface of the 310 mile-wide (498km) moon is thought to be covered in a thick layer of frozen water with a liquid ocean below.

*SATURN'S ENCELADUS MOON *
Enceladus is Saturn's sixth-largest moon - one of 62 - discovered in 1789 by William Herschel. In the early 1980s Nasa sent two Voyager spacecraft to the Saturnian system to capture the first close-up images of the moon. 

Voyager 1 made its flyby on 12 November 1980 but captured only poor resolution shots that revealed a highly reflective surface that didn't appear to have any craters on it.

Voyager 2 made its closest approach on 26 August 1981 during which its higher-resolution images instead revealed the surface to be heavily cratered in the north and lightly cratered around the equator. 

Nasa's Cassini craft began multiple flybys of Enceladus in 2005 and was able to identify cryovolcanoes near the south pole that shoot geyser-like jets of water vapour, and last month Cassini spotted evidence for a large ocean beneath Enceladus' surface.

Scientists recently proposed movement in Enceladus' core may create enough heat to keep the water liquid beneath the crust. 

It is thought to be one of the most likely places where alien life may have formed in our solar system.

On Wednesday, the Cassini probe will fly through a plume of ice, which is thought to shoot through the crust from the ocean below, above the south polar region of Enceladus.



Dr Curt Niebur, Cassini program scientist at Nasa, said: 'Cassini truly has been a discovery machine for more than a decade.

'This incredible plunge through the Enceladus plume is an amazing opportunity for Nasa and its international partners on the Cassini mission to ask, "Can an icy ocean world host the ingredients for life?"'

During the approach, instruments on board the craft will sample the spray and analyse the cocktail of chemicals within it.

Cassini has flown through ice plumes above Enceladus before but this will be the lowest altitude pass made to date.

The low altitude may allow the probe to detect heavy molecules including organics that may indicate the presence of life. 






Cassini's path through the icy fountains that erupt from Encleadus's south pole will give scientists their closest look at the jets. The spacecraft will fly to within 30 miles of the surface to gather data (illustrated)






It is also hoped the low sweep will allow Cassini to detect how much hydrothermal activity is taking place within Enceladus and how this hot water may impact the hidden ocean's habitability.

Dr Hunter Waite, the spacecraft’s ion and neutral mass spectrometer instrument team lead at Southwest Research Institute in San Antonio, said: 'Confirmation of molecular hydrogen in the plume would be an independent line of evidence that hydrothermal activity is taking place in the Enceladus ocean, on the seafloor.

'The amount of hydrogen would reveal how much hydrothermal activity is going on.'


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## CAPSLOCKSTUCK (Oct 27, 2015)

I am behaving like a 10 year old again....hard to contain my excitement, this stuff is so exciting.















Recent research suggests much of the eruption activity on the surface of Saturn's moon Enceladus could be in the form of broad, curtain-like eruptions, rather than discrete jets. Image credit: NASA/JPL-Caltech/SSI/PSI





3-D model of 98 of the 101 active geysers identified on Saturn's moon Enceladus





To date, 53 moons have been officially named. In alphabetic order, they are: Aegaeon, Aegir, Albiorix, Anthe, Atlas, Bebhionn,Bergelmir, Bestla, Calypso, Daphnis, Dione, Enceladus, Epimetheus, Erriapus, Farbauti, Fenrir, Fornjot, Greip, Hati, Helene,Hyperion, Hyrrokkin, Iapetus, Ijiraq, Janus, Jarnsaxa, Kari, Kiviuq, Loge, Methone, Mimas, Mundilfari, Narvi, Paaliaq, Pallene,Pan, Pandora, Phoebe, Polydeuces, Prometheus, Rhea, Siarnaq, Skadi, Skoll, Surtur, Suttung, Tarqeq, Tarvos, Telesto,Tethys, Thrym, Titan and Ymir.


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## CAPSLOCKSTUCK (Oct 29, 2015)

While the goal of this deep dive isn’t to detect life, the expectation is that it will provide fresh insights about how habitable the ocean environment is within Enceladus.









Beneath its icy exterior is an ocean, heated in part by tidal forces from Saturn and another moon, Dione.

It also features sea floor vents that expel water at least 194 degrees Fahrenheit and plumes of water vapour and icy particles that are ejected from its surface in geyser-like spouts.

“Although the October 28th fly-by won’t be the closest we’ve ever been to Enceladus, it is the closest fly-by over the south pole and through the plume,” Linda Spilker, the Cassini Project Scientist at the Jet Propulsion Laboratory, said in a statement.

There is the possibility that microscopic organisms similar to those that thrive around Earth’s deep sea volcanic vents might exist there.

The cosmic dust analyzer, meanwhile, will continue to collect and identify samples from the geysers on the moon’s south pole. Previous results from that instrument have also pointed toward hydrothermal activity—specifically, the presence of silica nanoparticles. A paper published today inNature Communications works backwards from the presence of those particles to infer that Enceladus has a carbon-rich core and high reaction temperatures close to 450°C in its ocean. If the probe finds other organic molecules, that’d reveal even more about the composition and conditions of the subsurface ocean.







To help answer the habitability question, scientists will be trying to determine how much hydrothermal activity is occurring within Enceladus.

Scientists also expect to learn more about the chemistry of the plume on Enceladus.

The low altitude of the encounter should offer Cassini greater sensitivity to heavier, more massive molecules, including organics, than the spacecraft has observed in previous efforts.

The fly-by should also help settle a debate of what the plume is made up of - column-like, individual jets, or sinuous, icy curtain eruptions -- or a combination of both.

The answer would make clearer how material is getting to the surface from the ocean below.

Since 2004, Cassini has been orbiting Saturn at a distance of about 980 million miles from Earth. In that time, it has made dozens of fly-bys of Saturn’s moons.

Cassini is expected to check in with its handlers at about 4 p.m. EDT (2300 GMT) today, providing a general status and health update, mission team members have said. The first flyby photos won't be released until Thursday night (Oct. 29) or Friday (Oct. 30) at the earliest, while initial analyses of plume particles will likely take a week or so.

The team is staying further away from Enceladus to conserve fuel, so they can save it up for the last two years of the space probe’s mission.

Cassini will say good bye to Enceladus in December, and then climb to a final set of orbits in Saturn’s outer rings. And in April 2017, Cassini will spend time between the planet’s atmosphere and its innermost ring, measuring ring masses and analyzing their composition before committing space-probe seppuku by diving toward the planet. The robot will actually become part of what it has spent its career analyzing—a fitting end.


Cassini-Huygens............an amazing mission
https://en.wikipedia.org/wiki/Timeline_of_Cassini–Huygens





Launch occurred at 4:43 a.m. EDT (8:43 UTC) on October 15, 1997, from Space Launch Complex 40 at Cape Canaveral Air Force Station





View of Saturn from _Cassini_, taken in March 2004, shortly before the spacecraft's orbital insertion in July 2004.





Saturn's moon Helene
https://en.wikipedia.org/wiki/Helene_(moon)


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## Drone (Oct 30, 2015)

So it happened ....







Unprocessed raw images acquired by NASA's Cassini spacecraft during a close flyby of the icy moon on Oct. 28, 2015

During this dramatic flyby the probe passed ~ 49 km above the moon's south polar region. The spacecraft will continue transmitting its data from the Enceladus encounter for the next several days. Cassini's next and final close Enceladus flyby will take place on *Dec. 19*, when the spacecraft will measure the amount of heat coming from the moon's interior. The flyby will be at an altitude of 4999 km.






Researchers will soon begin studying data from Cassini's gas analyzer and dust detector instruments, which directly sampled the moon's plume of gas and dust-sized icy particles during the flyby. Those analyses are likely to take several weeks, but should provide important insights about the composition of the global ocean beneath Enceladus' surface and any hydrothermal activity occurring on the ocean floor. The potential for such activity in this small ocean world has made Enceladus a prime target for future exploration in search of habitable environments in the solar system beyond Earth.

















And finally .... the plumes


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## CAPSLOCKSTUCK (Oct 30, 2015)




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## Drone (Nov 1, 2015)

Nasa decided to process Enceladus's raw images. Pictures are crispy now


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## CAPSLOCKSTUCK (Dec 2, 2015)

Cassini Probes Saturn's Magnetic Bubble --"Captures Water from Plumes of Enceladus"






Scientists have found the first direct evidence for explosive releases of energy in Saturn's magnetic bubble using data from the Cassini spacecraft, a joint mission between NASA, the European Space Agency, and the Italian Space Agency.

The research is reported in the journal Nature Physics. These “explosions” are produced in a process known as magnetic reconnection, something well studied at Earth and is an important part of Space Weather, involved in energising the radiation belts and producing displays of the Northern lights.

Space Physicists led by Lancaster University used data to show that Cassini had passed through the region at Saturn where magnetic reconnection was occurring, which has never before been observed.

One of the mysteries this gives us clues to answering is how Saturn’s magnetic bubble, known as its magnetosphere, gets rid of gas from Saturn’s tiny icy moon Enceladus. Through jets at its south pole, this tiny 500 km-sized moon ejects around 100 kg of water into space every second.

“Water from the Enceladus plume is trapped in Saturn’s magnetosphere. We know it can’t just stay there for ever and until now we have not been able to work out how it has been ejected from the magnetosphere,” said Chris Arridge, lead author of the study.

Previous work has suggested that magnetic reconnection cannot allow all enough plasma to escape from the magnetosphere. The results show that this is indeed possible.These results are also important for understanding Jupiter’s magnetosphere, where similar processes occur, and may also be relevant for other rapidly spinning astrophysical systems, such as young stars.

The Daily Galaxy via Lancaster University


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## CAPSLOCKSTUCK (Dec 17, 2015)

The Geysers on Saturn's Moon Enceladus Are Mysteriously Losing Steam

*



*


http://www.space.com/25328-ocean-on...eo.html#ooid=ZmcmN5cDpn1ZoKScX2MDuHfF8hc9flV3

The geysers, which blast material from Enceladus' subsurface ocean into space from the moon's south polar region, were first spotted by NASA's Saturn-orbiting Cassini spacecraft back in 2005. Now, a new study of Cassini data shows that the geysers' output has dropped by 30 to 50 percent since then.

This finding does not necessarily imply that Enceladus' jets are shutting down, said lead author Andrew Ingersoll, of the California Institute of Technology in Pasadena, who presented the new results Monday (Dec. 14) here at the annual fall meeting of the American Geophysical Union. But, he added, it's unclear what, exactly, is going on.

It's possible that the fissures through which the geysers spray are narrowing as more and more material accumulates on their walls, Ingersoll told Space.com.

"But why they would all act together is totally beyond me," he said.

It's also possible that the water pressure in the reservoirs feeding Enceladus' jets varies considerably over relatively long time spans, Ingersoll added, though he said it's hard to imagine how such a scenario would work in practice.

The new results will undoubtedly generate quite a bit of discussion among scientists, many of whom are keen to study Enceladus' plume in greater detail. The geysers, after all, offer a way to sample the moon's potentially life-hosting ocean without touching down.

Indeed, several different research teams have been developing life-detecting mission concepts that would hunt for biosignatures in Enceladus' plume material.


Enceladus Life Finder
Life Investigation for Enceladus





Enceladus


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## CAPSLOCKSTUCK (Dec 21, 2015)

Nasa has released a stunning image that captures Saturn's moons in perfect alignment with their planetary parent. The image shows the moons Enceladus and Tethys sitting in a line above Saturn's signature rings, with the smaller Enceladus in the foreground 






According to the space agency, each pixel of the image is approximately 10 miles (16km) wide, and the distance of the probe means the image gives a good approximation of the moons' sizes.

Tethys is 660 miles across (1,602 km), while Enceladus is less than half its size, at 313 miles across (504 km).


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## CAPSLOCKSTUCK (Dec 23, 2015)

Cassini has left Phoebe out in the dark but, being a sister moon she dererves to be shown in all her glory  even though she is way out in the dark.








In a rare image, taken by the Cassini spacecraft, the distant satellite has been captured in all its pockmarked glory. Phoebe orbits at a staggering distance of 8,049,668 miles (12,952,000km) from the planet and, unlike Saturn's other moons, it sits in darkness, reflecting just 6 per cent of the sunlight it receives


*SATURN'S DARK MOON PHOEBE *
Saturn's moon Phoebe orbits at a distance of 8,049,668 miles (12,952,000km) from the planet - almost four times the distance of its moon Iapetus.

Phoebe is roughly spherical and has a diameter of 132 miles (220km) - around one-fifteenth the diameter of Earth's moon.

Phoebe's orbit is also retrograde, which means it goes around Saturn the opposite direction than most other moons - as well as most objects in the solar system.

Unlike most major moons orbiting Saturn, Phoebe is dark and reflects only 6 per cent of the sunlight it receives.

Its darkness and irregular, retrograde orbit suggest Phoebe is most likely a captured object.

A captured object is a celestial body trapped by the gravitational pull of a much larger body, generally a planet.

Phoebe's darkness, in particular, suggests the small moon comes from the outer solar system.

Source: Nasa


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## CAPSLOCKSTUCK (Jan 19, 2016)

As we all know NASA's Cassini spacecraft has completed its final close flyby of Saturn's moon Enceladus, capturing detailed images of its furrows and ridges. It was the spacecraft's 22nd encounter with the icy satellite.
Cassini passed Enceladus at a distance of 3,106 miles (4,999km) on December 19, snapping stunning photos of the moon.
The images, transmitted by the spacecraft and released by NASA, show three views from Cassini.





NASA's Cassini spacecraft paused during its final close flyby of Enceladus to focus on the icy moon's craggy, dimly lit limb, with the planet Saturn beyond.






DC
Cassini captured this view featuring the nearly parallel furrows and ridges of Samakand Sulci


The flyby was Cassini's final close encounter with Enceladus – a fact that brings _“both sadness and triumph,”_ according to Earl Maize, Cassini project manager at NASA's Jet Propulsion Laboratory.
_"While we're sad to have the close flybys behind us, we've placed the capstone on an incredible decade of investigating one of the most intriguing bodies in the solar system,”_ Maize said in a press release.
Cassini will, however, continue to monitor Enceladus from a distance, until the end of its mission in September 2017. The future encounters will be more than four times farther than the latest flyby, at its closest point.






Cassini peered out over the Northern territory of Enceladus


The mission has proved to be incredibly successful, with Cassini discovering geologic activity on the moon in 2005, shortly after arriving at Saturn. This led to changes in the flight plan, in order to maximize the number of quality flybys of Enceladus.
Since the initial finding, Cassini has made a number of additional discoveries about the material pouring out of warm fractures near its south pole. The spacecraft's observations prompted scientists to announce strong evidence for a regional subsurface sea in 2014. They revised their understanding in 2015, confirming that the moon hosts a global ocean beneath its icy crust.
As a result of Cassini's findings, Enceladus is now considered one of the solar system's top spots to search for alien life.




For more information about the Cassini-Huygens mission visithttp://saturn.jpl.nasa.gov and http://www.nasa.gov/cassini. The Cassini imaging team homepage is at http://ciclops.org


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## Drone (Jan 30, 2016)

new image


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## Drone (Jan 31, 2016)

First Cassini Images from Latest Enceladus Flyby (old video, 2010 but I don't care, I haven't seen it before)










Relatively new raw video of Enceladus's rotation (October 2015)










Another old video about Cassini mission and Saturn's moons


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## Drone (Feb 7, 2016)

*Tethys & Janus*. Tethys looks like Enceladus in this image. Saturn's narrow F ring and the outer edge of its A ring slice across the scene.

Image gallery of Enceladus:






Enceladus is partially eclipsed by Saturn in this Cassini spacecraft view which also features the moon Titan in the distance.






Below a darkened Enceladus, a plume of water ice is backlit in this view of one of Saturn's most dramatic moons.






A crescent Enceladus appears with Saturn's rings in this Cassini spacecraft view of the moon.






Small water ice particles fly from fissures in the south polar region of Enceladus.


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## Drone (Feb 12, 2016)

No images of Enceladus but interesting research:

The first evidence that Saturn's upper atmosphere may, when buffeted by the solar wind, emit the same total amount of mass per second into its magnetosphere as its moon, Enceladus, has been found by UCL scientists working on the Cassini mission.

Professor Andrew Coates said: “Cassini never ceases to amaze us. First, it found that the plume of Enceladus is the main source of the water-rich magnetosphere which ultimately escapes from the planet. Now, we find that solar wind compression allows much lighter hydrogen ions to escape from Saturn's upper atmosphere at times.” Cassini is approaching its Grand Finale where the new orbital configuration will allow an even clearer picture of what role the ionosphere may play as a mass source at Saturn.






Aurora ~ 1000 km above the cloud tops of Saturn's south pole.

Enceladus Travel Poster






The discovery of Enceladus' icy jets and their role in creating Saturn's E-ring is one of the top findings of the Cassini mission to Saturn. Further Cassini mission discoveries revealed strong evidence of a global ocean and the first signs of potential hydrothermal activity beyond Earth - making this tiny Saturnian moon one of the leading locations in the search for possible life beyond Earth.

Credit: NASA/JPL


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## Drone (Feb 15, 2016)

New image of Dione






Dione appears cut in two by Saturn's razor-thin rings, seen nearly edge-on in a view from NASA's Cassini spacecraft. This scene was captured from just 0.02 degrees above the ringplane. The bright streaks of Dione's wispy terrain are seen near the moon's limb at right. The medium-sized crater Turnus (101 km, wide) is visible along Dione's terminator. The image was taken in visible light with the Cassini spacecraft narrow-angle camera. The view was acquired at a distance of ~ 2.3 million km from Dione. Image scale is 13.8 km per pixel.



















Cassini top images 2015 and nostalgic 1997 Cassini launch


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## Drone (Feb 23, 2016)

Tethys appears above the rings, while Enceladus sits just below center. Mimas hangs below and to the left of Enceladus.
The view was acquired at a distance of ~ 1.35 million km from Enceladus, with an image scale of 8 km per pixel.






The maps show heat coming from Titan's surface at a wavelength of 19 microns. Temperatures have been averaged around the globe from east to west to emphasize the seasonal variation from north to south. Black regions in the maps are areas for which there was no data.

Titan's surface temperature changes slowly over the course of the Saturn system's long seasons, which each last 7.5 years. As on Earth, the amount of sunlight received at each latitude varies as the sun's illumination moves northward or southward over the course of the 30-year-long Saturnian year.

*The maximum measured temperature on Titan remains 93.6 K [-179.6 degrees Celsius]*, with a minimum temperature at the winter pole only 3.5 degrees Celsius colder. This is a much smaller contrast than exists between Earth's warmest and coldest temperatures, which can vary by > 100 degrees Celsius.


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## Drone (Mar 25, 2016)

New images by Cassini


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## Drone (Mar 29, 2016)

Sustained eruptions on Enceladus explained by turbulent dissipation in tiger stripes

Enceladus, which probably has an ocean underlying its icy surface, has somehow managed to sprout multiple fissures along its south pole. These “tiger stripes” have been erupting vapor and tiny frost particles continuously along their entire length for decades and probably much longer.






Now scientists at the University of Chicago and Princeton University have pinpointed a mechanism by which cyclical tidal stresses exerted by Saturn can drive Enceladus' long-lived eruptions.

*Tidal pumping heats the water and the ice shell via turbulence, generating enough power (5 gigawatts) to produce eruptions*.


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## Drone (Apr 11, 2016)

Saturn's beautiful rings form a striking feature, cutting across this image of two of the planet's most intriguing moons [Titan and Enceladus]

At 5150 km across, Titan is 10 times larger than Enceladus, which measures just 505 km in diameter. *Titan is seen as a disc because light from the distant Sun is being refracted through the moon's dense atmosphere*.


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## RejZoR (Apr 12, 2016)

jboydgolfer said:


> mmmmmm.....enchilada's ... i love mexican food...see what i did there..very clever.



How do you call frozen encheladas? Enceladus


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## jboydgolfer (Apr 12, 2016)




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## Drone (Apr 12, 2016)

Interesting diagrams:

















101 geysers!


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## Drone (Apr 18, 2016)

Enceladus and Saturn diagrams















New sharp image:






A sinuous feature snakes northward from Enceladus' south pole like a giant tentacle. This feature, which stretches from the terminator near center, toward upper left, is actually tectonic in nature, created by stresses in Enceladus' icy shell. Geologists call features like these on Enceladus *Y-shaped discontinuities*. These are thought to arise when surface material attempts to push northward, compressing or displacing existing ice along the way. Such features are also believed to be relatively young based on their lack of impact craters - a reminder of how surprisingly geologically active Enceladus is.


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## Drone (May 2, 2016)

The water-world Enceladus appears here to sit atop Saturn's rings like a drop of dew upon a leaf. Even though it appears like a tiny drop before the might of the giant Saturn, Enceladus reminds us that even small worlds hold mysteries and wonders to be explored.

The view was obtained at a distance of ~ 1.5 million km from Saturn.


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## Drone (May 9, 2016)

During its first few years after arriving at Saturn in 2004, Cassini discovered that Enceladus continuously spews a broad plume of gas and dust-sized ice grains from the region around its south pole. This plume extends hundreds of miles into space, and is several times the width of the small moon itself. Scores of narrow jets burst from the surface along great fractures known as "tiger stripes" and contribute to the plume. The activity is understood to originate from the moon's subsurface ocean of salty liquid water, which is venting into space.

Cassini has shown that > 90 % of the material in the plume is *water vapor*. This gas lofts dust grains into space where sunlight scatters off them, making them visible to the spacecraft's cameras. Cassini has even collected some of the particles being blasted off Enceladus and analyzed their composition.

Previous observations saw the _eruptions spraying 3 times as much icy dust into space when Enceladus neared the farthest point in its elliptical orbit around Saturn_.

So on March 11, 2016, during a carefully planned observing run, Cassini set its gaze on Epsilon Orionis, the central star in Orion's belt. At the appointed time, Enceladus and its erupting plume glided in front of the star. Cassini's UV imaging spectrometer (or UVIS) measured how water vapor in the plume dimmed the star's UV light, revealing how much gas the plume contained.






Since lots of extra dust appears at this point in the moon's orbit, scientists expected to measure a lot more gas in the plume, pushing the dust into space. But instead of the expected huge increase in water vapor output, the UVIS instrument only saw a slight bump - just a 20 % increase in the total amount of gas.






This insight revealed something subtle, but important, according to Larry Esposito, UVIS team lead at the University of Colorado at Boulder. "We had thought the amount of water vapor in the overall plume, across the whole south polar area, was being strongly affected by tidal forces from Saturn. Instead we find that the small-scale jets are what's changing." *This increase in the jets' activity is what causes more icy dust grains to be lofted into space*, where Cassini's cameras can see them, Esposito said.


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## Drone (May 9, 2016)

Bouncing Waves Off Titan

watch here

During Cassini's T-119 Titan flyby on May 6, the Radio Science Subsystem [RSS] will observe an atmospheric occultation, in which Cassini appears to go behind Titan's atmosphere as seen from Earth.










Another View of Titan Flyby 119

watch here

Two interesting Cassini videos by  NASASolarSystem


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## Drone (Jul 5, 2016)

New images:






*Pan* and moons like it have profound effects on Saturn's rings. The effects can range from clearing gaps, to creating new ringlets, to raising vertical waves that rise above and below the ring plane. All of these effects, produced by gravity, are seen in this image.






Saturn's rings and the icy moon *Enceladus*. Upon closer inspection, Saturn's night side is also visible (near top center), faintly illuminated by sunlight reflected off the rings.


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## Drone (Jul 17, 2016)

NASA's Cassini spacecraft obtained these views of the south polar area of Saturn's moon Enceladus in visible and near-visible (ultraviolet and infrared) light and synthetic-aperture radar (SAR).






Cassini images of Saturn's moon Enceladus backlit by the Sun show the fountain-like sources of the fine spray of material that towers over the south polar region. The image was taken looking more or less broadside at the "tiger stripe" fractures observed in earlier Enceladus images. It shows discrete plumes of a variety of apparent sizes above the limb of the moon. The greatly enhanced and colorized image shows the enormous extent of the fainter, larger-scale component of the plume.







Saturn's Hexagon in Motion

The hexagon is just a current of air, and weather features out there that share similarities to this are notoriously turbulent and unstable. A hurricane on Earth typically lasts a week, but this has been here for decades - and who knows - maybe centuries.

- Andrew Ingersoll, Cassini Imaging Team


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## Drone (Oct 2, 2016)

Saturnian moons are awesome, it's time to bump this thread






This image, which is composed of data obtained by NASA's Cassini spacecraft [on Oct. 11, 2005, and Oct. 17, 2010], shows the topography of a mountain known as *Janiculum Dorsa* on *Dione*. Color denotes elevation, with red as the highest area and blue as the lowest.

Janiculum Dorsa is a 800-km-long mountain and ranges in height from 1 to 2 km. An analysis of the topography data suggests the crust under the mountain puckers as much as 0.5 km. This bending of the crust suggests the icy crust was warm at some time in recent history. The best explanation for such behavior is the existence of a subsurface ocean under the mountain when it formed.






Fine topographic detail and color variations are revealed in this 11-image, false color mosaic taken during Cassini's second close flyby of Saturn's moon *Enceladus*, on March 9, 2005.






Cassini took this image of the ropy, taffy-like topography on Saturn's moon Enceladus as it soared above the icy moon on Feb. 17, 2005.

This view, ~ 60 km across, shows several different kinds of ridge-and-trough topography, indicative of a variety of horizontal forces near the surface of this 505-km diameter satellite.






Perspective view of heavily fractured, cratered terrain on *Enceladus*, using images from the Cassini spacecraft. The view is ~ 5 km across and shows hill and rifts coated with snow from Enceladus' plumes of ice and vapor. This image was developed by Paul Schenk, Ph.D., of the USRA Lunar Planetary Institute.

A nice video by the New York Times


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## Drone (Oct 28, 2016)

Old but nice video


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## Drone (Feb 6, 2017)




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## Drone (Feb 17, 2017)

*An Ice World...With an Ocean?*


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## Drone (Mar 6, 2017)

New image






The view was obtained at a distance of ~66000 km from Enceladus.


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