The Misty Mini-Moons of Saturn
And we come to the end of our punt through the waters of the Saturn system, with an examination of its smaller moons Universe of Water playlist: https://www.youtube.com/playlist?list=PLa0TgREKn12jUoCK0N4qQVgTgGalS6KDG CORRECTIONS: 13:49 : Water reacts with the crust, causing the crust to combine with the oxygen in the water and hydrogen to be released. 18:20 : Lagrange points are similar to hills; some are low, rolling and stable, others are narrow and sharp, and require constant readjustment to retain position. 22:32 : As can be plainly seen in the diagram, Iapetus's inclination is over 15 degrees, not 7. To be honest I can't remember where I came up with that one.
Universe of Water playlist: https://www.youtube.com/watch?v=M186s319ob8&list=PLa0TgREKn12jUoCK0N4qQVgTgGalS6KDG
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Cassini: Coming Attractions at Saturn
What incredible things will the Cassini spacecraft at Saturn see and do over the next few years? Here's a preview.
Mimas digging the Cassini Division.
Zoom in the Cassini Division region
The opening of the Cassini Division by the migration of Mimas
Mimas (grey dot) digs the Cassini Division.
Ring particles are 1m..
10 Moons People Can Actually Live On
One day it will be an amazing scientific accomplishment when we colonize and bring life to a moon like Saturn's icy Enceladus. Subscribe for new videos weekly! 5. Triton
Photographs and data sent back from the Voyager 2 spacecraft back in August of 1989 showed that the surface of Triton, Neptune’s largest moon, was made up of nitrogen ice and rock. The suspicion of liquid water being hidden beneath the surface was raised. Even though the moon has an atmosphere, it would be pretty much the same as if it didn’t have one because of how thin it is. The average temperature on the moon is an unbelievable -391 degrees Fahrenheit, making it the coldest body in the entirety of our solar system. 4. Mimas
Also known as the “Death Star” moon and for good reason. Mimas is one of Saturn’s icy and rocky moons. Mimas might have an ocean located beneath its cold and unwelcoming -looking surface, which may possibly be better adapted for life. Close study of the Cassini footage by scientists shows that Mimas looks to rock back and forth as it went around on its orbit. This could imply activity underneath its surface. However, scientists were very wary with what they found, stating that there hadn’t been any other signs that point to geological activity. They merely stated that if an ocean was discovered, the moon could definitely be a candidate for being colonized. It’s believed that the theoretical ocean would be about 15 to 18 miles below the surface. If the rocking movement that supports this theory of an ocean proves to be false, then the movement is mostly likely because of a misshapen core due to the strong gravitational pull caused by Saturn’s rings 3. Callisto
Exactly the same size as the planet Mercury, Callisto is Jupiter’s second largest moon that looks like it has a large liquid ocean hidden within its icy surface. The surface of Callisto mainly made up of craters and what are basically fields of ice. Callisto also has a relatively thin atmosphere consisting of carbon dioxide. Research that already been performed has suggested that this atmosphere is being filled up again and again by carbon dioxide that is released from below the surface because it is too thin to stay in place. Collected data implies the chance that oxygen could also be actively present inside of the atmosphere, but there would need to be further tests to confirm if this theory holds true. Callisto is positioned in a safe enough space from Jupiter that the giant planet’s radiation levels would be very mild. 2. Ganymede
Ganymede happens to be Jupiter’s largest moon and like other masses, in our solar system, it could potentially prove to have water trapped underneath its surface. If you were to compare it to other ice-covered moons, Ganymede’s surface is believed to be relatively thin and should be much easier to break through. This moon also happens to be the only moon with its own gravitational field that creates its own auroras, like the ones that are produced here on earth. Their pattern in movement also leads scientists to theorize there is an ocean trapped underneath the surface. Because of Ganymede’s thin oxygen atmosphere, it is too thin to support our life but maybe enough to support terraforming. Back in 2012, the European Space Agency got the okay to go ahead and launch a mission to go and explore Ganymede and two other of Jupiter’s moons, Europa and Callisto. The operation is scheduled to launch in 2022 and reach the moon 10 years later. Out of the three moons to be explored, scientists believe that Ganymede will have the best environment to study and potentially support life, if possible.
1. The Moon
The first moon that mankind would colonate would, of course, be the earth’s very own moon. It’s been described as a good “dress rehearsal” for potential colonization missions in the future because of how close it is to earth compared to all the other moons. Earlier in March of this year, there was a story that was going around that this type of operation could be carried out within the next 10 years or so. NASA astrobiologist Chris McKay is one of the individuals whose onboard with making this mission come to fruition. His opinion is that other missions to the moon have failed because of the high cost, but his team has a plan that requires little compared to previous missions. Although NASA’s current focus is to get humans to land on Mars, McKay says that that won’t come to light until they can first get to the moon and set up permanent bases there first.
Mimas The Moon That Orbits Saturn
For our Final project in Solar Systems Astronomy class
Saturn's Moons and Rings May Be Younger Than the Dinosaurs
Saturn's Moons and Rings May Be Younger Than the Dinosaurs Some of Saturn's icy moons may have been formed after many dinosaurs roamed the Earth. New computer modeling of the Saturnian system suggests the rings and moons may be no more than 100 million years old. Saturn hosts 62 known moons. All of them are influenced not only by the gravity of the planet, but also by each other's gravities. A new computer model suggests that the Saturnian moons Tethys, Dione and Rhea haven't seen the kinds of changes in their orbital tilts that are typical for moons that have lived in the system and interacted with other moons over long periods of time. In other words, these appear to be very young moons. "Moons are always changing their orbits. That's inevitable," Matija Cuk, principal investigator at the SETI Institute and one of the authors of the new research, said in a statement. "But that fact allows us to use computer simulations to tease out the history of Saturn's inner moons. Doing so, we find that they were most likely born during the most recent 2 percent of the planet's history." The age of Saturn's rings has come under considerable debate since their discovery in the 1600s. In 2012, however, French astronomers suggested that some of the inner moons and the planet's well-known rings may have recent origins. The researchers showed that tidal effects — which refer to "the gravitational interaction of the inner moons with fluids deep in Saturn’s interior," according to the statement — should cause the moons to move to larger orbits in a very short time. "Saturn has dozens of moons that are slowly increasing their orbital size due to tidal effects. In addition, pairs of moons may occasionally move into orbital resonances. This occurs when one moon's orbital period becomes a simple fraction of another. For example, one moon could orbit twice as fast as another moon, or three times as fast. Once an orbital resonance takes place, the moons can affect each other's gravity, even if they are very small. This will eventually elongate their orbits and tilt them from their original orbital plane. By looking at computer models that predict how extended a moon's orbit should become over time, and comparing that with the actual position of the moon today, the researchers found that the orbits of Tethys, Dione and Rhea are "less dramatically altered than previously thought," the statement said. The moons don't appear to have moved very far from where they were born. To get a more specific value for the ages of these moons, Cuk used ice geysers on Saturn's moon Enceladus. The researchers assumed that the energy powering those geysers comes from tidal interactions with Saturn and that the level of geothermal activity on Enceladus has been constant, and from there, inferred the strength of the tidal forces from Saturn. Using the computer simulations, the researchers concluded that Enceladus would have moved from its original orbital position to its current one in just 100 million years — meaning it likely formed during the Cretaceous period. The larger implication is that the inner moons of Saturn and its gorgeous rings are all relatively young. (The more distant moons Titan and Iapetus would not have been formed at the same time.) "So the question arises — what caused the recent birth of the inner moons?" Cuk said in the statement. "Our best guess is that Saturn had a similar collection of moons before, but their orbits were disturbed by a special kind of orbital resonance involving Saturn's motion around the sun. Eventually, the orbits of neighboring moons crossed, and these objects collided. From this rubble, the present set of moons and rings formed." The research is being published in the Astrophysical Journal.
worlds apart
Although Mimas and Pandora, shown here, both orbit Saturn, they are very different moons. Pandora, "small" by moon standards (50 miles or 81 kilometers across) is elongated and irregular in shape. Mimas (246 miles or 396 kilometers across), a "medium-sized" moon, formed into a sphere due to self-gravity imposed by its higher mass. The shapes of moons can teach us much about their history. For example, one explanation for Pandora's elongated shape and low density is that it may have formed by gathering ring particles onto a dense core. This view looks toward the unilluminated side of the rings from 0.26 degrees below the ring plane. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on July 26, 2015. The view was obtained at a distance of approximately 485,000 miles (781,000 kilometers) from Pandora. Image scale is 3 miles (5 kilometers) per pixel. Mimas is 904,000 miles (1.4 million kilometers) from the spacecraft in this image. The scale on Mimas is 5.4 miles (8.4 kilometers) per pixel. The Cassini mission is a cooperative project of NASA, ESA (the European Space Agency) and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colorado. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov or http://www.nasa.gov/cassini . The Cassini imaging team homepage is at http://ciclops.org . Credit: NASA/JPL-Caltech/Space Science Institute Last Updated: Oct. 13, 2015
Editor: Tony Greicius
Saturn: Crash Course Astronomy #18
Saturn is the crown jewel of the solar system, beautiful and fascinating. It is a gas giant, and has a broad set of rings made of ice particles. Moons create gaps in the rings via their gravity. Saturn has dozens of moons, including Titan, which is as big as Mercury and has a thick atmosphere and lakes of methane; and Enceladus which has an undersurface ocean and eruptions of water geysers. While we are still uncertain, it is entirely possible that either or both moons may support life. This episode was brought to you by Squarespace http://www.squarespace.com
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-- Table of Contents
Saturn is a Gas Giant 0:33
Moons Create Gaps in the Ice Rings 5:17
Dozens of Moons 6:18
Titan’s Methane Lakes 7:56
Enceladus’s Water Geysers 8:33
Life Potential 9:30 -- PBS Digital Studios: http://youtube.com/pbsdigitalstudios Follow Phil on Twitter: https://twitter.com/badastronomer Want to find Crash Course elsewhere on the internet?
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Saturn http://saturn.jpl.nasa.gov/multimedia/images/saturn/images/IMG004899.jpg [credit: NASA/JPL-Caltech/Space Science Institute/G. Ugarkovic]
Interiors http://solarsystem.nasa.gov/multimedia/gallery/gas_interiors.jpg [credit: Lunar and Planetary Institute]
Saturn Ring Plane Crossing http://www.spacetelescope.org/static/archives/images/large/opo9616a.jpg [credit: Erich Karkoschka (University of Arizona Lunar & Planetary Lab) and NASA/ESA]
Translucent Rings http://www.jpl.nasa.gov/spaceimages/details.php?id=PIA18295 [credit: NASA/JPL-Caltech/Space Science Institute]
Catching its Tail http://www.ciclops.org/view_media/34501/Catching_Its_Tail?js=1 [credit: NASA/JPL-Caltech/Space Science Institute]
Enter the Vortex http://www.ciclops.org/view_media/38030/Enter_the_Vortex_In_Psychedelic_Color [credit: NASA/JPL/Space Science Institute]
The Rose http://www.nasa.gov/mission_pages/cassini/multimedia/pia14944.html#.VSwz-5TF_Z0 [credit: NASA/JPL/Space Science Institute]
Ice http://www.nasa.gov/images/content/205796main_PIA10081-hires.jpg [credit: NASA/JPL/University of Colorado]
Saturn’s rings to scale http://www.slate.com/blogs/bad_astronomy/2014/05/02/saturn_s_rings_to_scale_thinner_than_paper.html [credit: NASA/JPL/Space Science Institute]
Saturn’s Ring Plane http://en.wikipedia.org/wiki/Rings_of_Saturn#/media/File:Saturn%27s_ring_plane.jpg [credit: NASA/JPL/Space Science Institute - Cassini-Huygens/NASA]
Saturn http://saturn.jpl.nasa.gov/multimedia/images/saturn/images/IMG004899.jpg [credit: NASA/JPL-Caltech/Space Science Institute/G. Ugarkovic]
Shaping the Drapes (video) http://ciclops.org/view.php?id=1361&js=1 [credit: NASA/JPL/Space Science Institute]
Peaks http://en.wikipedia.org/wiki/Rings_of_Saturn#/media/File:PIA11668_B_ring_peaks_2x_crop.jpg [credit: NASA / Jet Propulsion Lab / Space Science Institute]
Mimas Cassini http://en.wikipedia.org/wiki/Mimas_(moon)#/media/File:Mimas_Cassini.jpg [credit: NASA / JPL-Caltech / Space Science Institute]
Cassini NAC RGB https://www.flickr.com/photos/ugordan/6896462870/sizes/o/in/photostream/ [credit: NASA/JPL-Caltech/Space Science Institute/G. Ugarkovic]
Titan http://en.wikipedia.org/wiki/Titan_(moon)#/media/File:Titan2005.jpg [credit: NASA/JPL/Space Science Institute]
Titan’s Nile River http://www.esa.int/spaceinimages/Images/2012/11/Titan_s_Nile_River [credit: NASA/JPL–Caltech/ASI]
Lakes http://photojournal.jpl.nasa.gov/figures/PIA17655_fig1.jpg [credit: NASA/JPL-Caltech/ASI/USGS]
Enceladus http://www.ciclops.org/view_media/39541/Bursting-at-the-Seams [credit: NASA/JPL/Space Science Institute]
Iapetus Ridge http://en.wikipedia.org/wiki/Equatorial_ridge#/media/File:Iapetus_706_1419_1.jpg [credit: NASA (Cassini probe), Matt McIrvin (image mosaic)]
Hyperion http://ciclops.org/media/ir/2005/1507_3730_1.jpg [credit: NASA/JPL/Space Science Institute]
Saturn eclipse mosaic http://en.wikipedia.org/wiki/Rings_of_Saturn#/media/File:PIA17172_Saturn_eclipse_mosaic_bright_crop.jpg [credit: NASA / JPL-Caltech / Space Science Institute]
Cassini Maps Saturn's Moon Mimas
Cassini Maps Saturn's Moon Mimas 2004-2014. Digital map of Mimas in 3 colors (IR, Green, UV) at a resolution of 200 meters. Digital cartography and mosaics by Dr. Paul Schenk with visualization by John Blackwell of the Lunar and Planetary Institute. Image data are from the Imaging Science Subsystem (ISS) on the Cassini orbiter (NASA, JPL).
Global Mapping of Saturn's Icy Moons 2004-2014: Iapetus, Rhea, Dione, Tethys, Enceladus, and Mimas
Cassini mosaics in 3 colors (IR, Green, UV) at 0.1 to 1.0 kilometers resolution. Digital cartography and mosaics by Dr. Paul M. Schenk with visualization by John Blackwell, Lunar and Planetary Institute. Cassini mission is managed by NASA's Jet Propulsion Laboratory.
Saturn's 'Death Star' and Hubble's Latest Masterpiece
SciShow Space News takes you to the solar system’s own Death Star -- Saturn’s moon Mimas, where something mysterious is going on. Plus, we share a stunning new photo from the Hubble Space Telescope that holds a few surprises! Hosted by: Caitlin Hofmeister
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http://news.sciencemag.org/space/2014/10/does-mimas-have-ocean-under-icy-cap
http://www.eurekalert.org/jrnls/sci/emb_scipak/pdf/tajeddine141017.pdf
https://cornell.app.box.com/mimas
http://hubblesite.org/newscenter/archive/releases/2014/39/full/
Saturn's Death Star Moon Mimas May Contain Life
The Fortean Slip Science Minute 54 Saturn's "Death Star" moon Mimas may contain life. Source:
http://www.techtimes.com/articles/18155/20141017/saturn-s-moon-is-harboring-secrets-a-buried-ocean-or-elongated-core.htm Like us on Facebook at...
https://www.facebook.com/theforteanslip The Fortean Slip Facebook Group Page
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http://www.sasquatchscoop.com bigfootcrossroads
http://bigfootcrossroads.blogspot.com/ "The Machine Thinks" Kevin MacLeod (incompetech.com)
Licensed under Creative Commons: By Attribution 3.0
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Saturn's 'Death Star' Moon Might Have A Hidden Ocean
The smallest of Saturn's main moons, Mimas, wobbles as it orbits. Research reveals it might be due to a global ocean underneath its icy surface. Follow Katherine Biek: http://www.twitter.com/katherinebiek
See more at http://www.newsy.com Sources:
NASA https://www.youtube.com/watch?v=8CHHPHZIIMs
Science Magazine http://www.sciencemag.org/content/346/6207/322
NASA https://www.youtube.com/watch?v=QhTAyeNbU6M
BBC http://www.bbc.com/news/science-environment-29613671
The Register http://www.theregister.co.uk/2014/10/17/cassini_spots_death_star_moon_of_saturn_is_unexpectedly_wobbly/
Euronews http://www.euronews.com/2014/10/17/saturn-moon-may-have-life-friendly-underground-ocean/
International Business Times http://www.ibtimes.com/saturns-icy-moon-mimas-may-contain-ocean-could-provide-life-friendly-environments-1706754
Discovery http://news.discovery.com/space/saturns-death-star-moon-may-hide-subsurface-ocean-141016.htm
NASA http://www.nasa.gov/mission_pages/cassini/multimedia/pia12867.html Image via: NASA
https://www.youtube.com/watch?v=QhTAyeNbU6M
Saturn moon Mimas may have underground ocean
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Saturn's icy moon Mimas may have a thin global ocean buried miles beneath its icy surface. Report by Claire Lomas. Current affairs, amazing footage and incredible stories. Welcome to ODN - On Demand News. Formerly the ITN YouTube channel, ODN is your home for the top visual stories happening across the globe. Like us on Facebook: http://bit.ly/ODNface
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Moon Shadows on Saturn
Saturn's wide, but very thin, rings are tilted with respect to its plane of orbit around the Sun. Once every 15 years, the rings are edge-on (perpendicular) to the Sun. During those times, some of Saturn's moons can cast shadows across the rings. This time-lapse movie shows the icy moons Enceladus, Mimas, Dione, and Tethys orbiting Saturn. Enceladus, seemingly chased by Mimas, is first to speed past the rings and in front of the planet. Both moons cast small shadows on the planet, but only Enceladus casts a shadow on the rings. The orbit of Mimas is inclined so that its shadow misses the rings. Dione is next, and its long shadow also tracks across the ring system. As the three moons move across Saturn's disk, the viewer catches a fleeting view of Tethys as it moves behind the planet on the right. The 30-second movie is created from Hubble images taken over a 9½-hour span. The images were taken Nov. 17, 1995, with Hubble's Wide Field and Planetary Camera 2. The movie has a standard aspect ratio, but is presented within a widescreen frame - the black bars along the sides are normal. For more information or to download this video, visit: http://hubblesite.org/videos/video_details/8-moon-shadows-on-saturn For more videos, visit: http://hubblesite.org/videos/
That's no moon. It's a space station.
The clip is from "Star Wars: Episode IV - A New Hope".
Why can't Mimas be more like Enceladus? - Bill McKinnon (SETI Talks)
Pity poor Mimas! The "that's no moon" moon of Saturn ought to be as famous as its sibling Enceladus. All other things being equal, Mimas should be more strongly tidally heated, but this is clearly not the case. This talk will review the latest Cassini findings for both moons, including the astonishing heat flow coming from Enceladus' south pole. It turns out that Mimas' lack of geologic activity is no surprise — the real question is how does Enceladus support its heat flow, active tectonics, and erupting plumes? Episodicity may be key, but even more radical notions have been proposed. These ideas, and perhaps new ones from the 23-24 May Enceladus Workshop at the SETI Institute, will also be discussed.
Saturn's moon Mimas moving against the rings.
NASA's Cassini mission caught Mimas flying against the rings. I sequenced these frames after I saved from them from the raw uncalibrated images when they were coming in. Jason H.
Saturn's Mysterious Moons
Launched three years before the new century... a spacecraft wound its way through the empty reaches of the solar system. On Earth, its progress was little noted, as it swung twice by the planet Venus, then our moon. And Earth. The asteroid belt. And Jupiter. Almost seven years later, on the first of July 2004, the Cassini probe entered the orbit of Saturn. It then began to compile what has become one of the greatest photographic collections of all time, of a giant gas planet, surrounded by colorful rings, guarded by a diverse collection of moons, and millions of tiny moonlets. Within this record, is a trail of clues... pointing to the energy sources and complex chemistry needed to spawn life. What are these mysterious worlds telling us about the universe, and Earth? In the outer reaches of the solar system, a billion and a half kilometers from the Sun... there is a little world known as Enceladus. Nearly all of the sunlight that strikes its icy surface is reflected back into space, making it one of the brightest objects in the solar system. At its equator, the average temperature is minus 198 degrees Celsius. It can rise about 70 degrees higher in grooves that stretch across the south pole like tiger stripes. Looming over it is the giant planet Saturn. In myth, Saturn - the Roman name for the primal Greek God Chronos - was the youngest son of Gaia, or Earth, and Uranus, sky. Wielding a scythe provided by his mother, the story goes, Saturn confronted his abusive father, castrating him. The blood of Uranus flowed into the seas, fertilizing the Earth and giving rise to Enceladus and other giant offspring. Saturn's moon Enceladus has its own tangled story. In 2005, the Cassini spacecraft spotted plumes of water vapor shooting out into space from its south pole. More recent close encounters have revealed jets of water, flavored by slightly salty chemical compounds, spewing out from vents in the rough, cracked polar terrain. That may mean that Enceladus harbors a remarkable secret below its frigid surface: A liquid ocean, and perhaps, a chemical environment that could spawn simple life forms. It's not the only promising stop in the realm of Saturn. The moon Titan is often said to resemble Earth in its early days. It is lined with volcanoes and a hazy atmosphere rich in organic compounds. While Enceladus is the size of Great Britain, Titan is ten times larger, 50% larger than our moon, and the second largest moon in our solar system. We've known about Titan since the astronomer Christian Huygens discovered it in 1655, and Enceladus since William Herschel spotted it in August 1789, just after the start of the French Revolution. Scientists began to investigate these moons in earnest with the launch of the two Voyager spacecraft in 1977. The lineup of outer planets in the solar system allowed the spacecraft to fly past each of them. They disclosed new details about their magnetic fields, atmospheres, ring systems, and inner cores. But what really turned heads were the varied shapes and surfaces of their moons. They've all been pummeled over the millennia by wayward asteroids and comets. A few appear to be sculpted by forces below their surfaces. Neptune's largest moon Triton has few craters. It's marked with circular depressions bounded by rugged ridges. There are also grooves and folds that stretch for dozens of miles, a sign of fracturing and deforming. Triton has geysers too, shooting some five miles above the surface. But on this frigid moon -- so far from the Sun -- the liquid that spouts is not water but nitrogen. Tiny Miranda, one of 27 known moons that orbit Uranus, wears a jumbled skin that's been shaped and reshaped by forces within. Jupiter's moon Io -- orbiting perilously close to the giant planet is literally turning itself inside out. Rivers of lava roll down from open craters that erupt like fountains.
Flying by Europa, Voyager documented a complex network of criss-crossing grooves and ridges. In the 1990s, the Galileo spacecraft went back to get a closer look. It found that Europa's surface is a crazy quilt of fractured plates, cliff faces and gullies... amid long grooves like a network of superhighways. How did it get like this? Then, heat rising up through a subsurface ocean of liquid water cracks, and shifts, and spreads the icy surface in a thousand different ways. Europa's neighbors, Callisto and Ganymede, show similar features, suggesting they too may have liquid oceans below their surfaces.
Crossing outward to Saturn, Voyager found a similar surface on the moon Enceladus. So when the Cassini spacecraft arrived in 2004, it came looking for answers to a range of burning questions: if this moon and others have subsurface oceans? Do they also have the ability to cook up and support life? And what could they tell us about the origin of life throughout the galaxy?