Photos: Saturn and its moons A bright disruption in Saturn's narrow F ring suggests it may have been disturbed recently by the interaction of a small object embedded in the ring itself. They are hard to see, but their handiwork reveals their presence, and scientists use the Cassini spacecraft to study these stealthy sculptors of the F ring. Hide Caption 1 of 21 
 
 Photos: Saturn and its moons Saturn's moons Tethys, Enceladus and Mimas are shown in this image taken by the Cassini spacecraft on December 3, 2015. Tethys is above the rings, Enceladus is below the rings in the center of the image, and Mimas is below and to the left. Cassini has been exploring Saturn and its moons since 2004. The mission is scheduled to end in September 2017. Hide Caption 2 of 21 
 
 Photos: Saturn and its moons Saturn's icy moon Dione, with giant Saturn and its rings in the background, was captured in this mosaic of images just prior the Cassini spacecraft's final close approach to the moon on August 17, 2015. Scientists combined nine visible light images to create the mosaic. Cassini was at distances ranging from approximately 106,000 miles (170,000 kilometers) to 39,000 miles (63,000 kilometers) from Dione when the images were taken. Hide Caption 3 of 21 
 
 Photos: Saturn and its moons NASA's Cassini spacecraft has spotted mysterious reddish streaks on the surface of Saturn's icy moon Tethys. The red streaks are only a few miles wide but several hundred miles long. The images were taken in April. Scientists aren't sure what's causing the streaks. Hide Caption 4 of 21 
 
 Photos: Saturn and its moons This mosaic of Saturn's moon Mimas was created from images taken by Cassini in February 2010. A recent study indicates the moon may contain a liquid water ocean. Hide Caption 5 of 21 
 
 Photos: Saturn and its moons Cassini glided high above Saturn in October 2013 to capture this 36-image mosaic of the ringed planet. The colors of the planet appear natural, just as the human eye would see them. Hide Caption 6 of 21 
 
 Photos: Saturn and its moons Plumes of water ice and vapor shoot up from the surface of Saturn's moon Enceladus in this two-image mosaic taken by Cassini in November 2009. Analysis by NASA scientists indicated that water can reach the Saturnian moon's surface. Hide Caption 7 of 21 
 
 Photos: Saturn and its moons A small, bright blip can be seen on the outermost edge of Saturn's rings in this image taken in April 2013. The bump in the smooth ring structure is an icy object that could provide clues to how Saturn's moons formed. Hide Caption 8 of 21 
 
 Photos: Saturn and its moons This false-color image of Saturn's north polar storm looks like a giant red rose surrounded by green foliage. Measurements indicate the storm's eye is a staggering 1,250 miles across with cloud swirling as fast as 330 mph. Hide Caption 9 of 21 
 
 Photos: Saturn and its moons Saturn's rings cast a narrow shadow on its surface in this image taken in August 2009. Hide Caption 10 of 21 
 
 Photos: Saturn and its moons The scars of time and space mark the surface of Saturn's moon Enceladus. Saturn has at least 62 moons in its orbit. Hide Caption 11 of 21 
 
 Photos: Saturn and its moons The Saturn-facing side of Enceladus is illuminated by light bouncing off the planet. Plumes of water ice can be seen streaming off the moon's southern pole. Hide Caption 12 of 21 
 
 Photos: Saturn and its moons Saturn's moon Rhea is seen from approximately 174,181 miles away in this March 2013 image. Hide Caption 13 of 21 
 
 Photos: Saturn and its moons Rhea's surface is pockmarked with craters from billions of years of impacts. The moon is Saturn's second-largest, with a diameter of 949 miles. Hide Caption 14 of 21 
 
 Photos: Saturn and its moons Saturn's largest moon, Titan, has a diameter of 3,200 miles. It looks like a fuzzy orange ball because of its atmosphere. Hide Caption 15 of 21 
 
 Photos: Saturn and its moons Though it's the largest moon orbiting Saturn, Titan is dwarfed by Saturn itself. Hide Caption 16 of 21 
 
 Photos: Saturn and its moons Saturn has a small moon called Dione orbiting about 234,000 miles away. That's about the same distance Earth is from its moon. Hide Caption 17 of 21 
 
 Photos: Saturn and its moons The surface of Dione is seen in this May 2012 image. Hide Caption 18 of 21 
 
 Photos: Saturn and its moons Tethys, top left, is dwarfed by Saturn as it orbits the planet, though scientists think the moon is much larger than Saturn's ring system. Hide Caption 19 of 21 
 
 Photos: Saturn and its moons The Odysseus Crater spans 280 miles across the northern hemisphere of Tethys. Hide Caption 20 of 21 

 When researchers talk about planets and moons forming, it’s usually an event that took place billions and billions of years ago - a timeframe that's so massive, it's hard for us to really comprehend. But that can no longer be said about Saturn’s famous moons and rings, because they might have formed a mere 100 million years ago, which makes them younger than most dinosaurs. 
 
 According to researchers from the Search for Extra-terrestrial Intelligence Institute (SETI), a new computer model shows evidence that Saturn’s inner moons and rings are actually a relatively modern creation, especially considering that Saturn itself, along with the other planets in our Solar System, formed some 4.5 billion years ago. 
 
 The discovery came from analysing orbital data from the planet’s moons. Basically, since Saturn has so many moons flying around it, they have to share space, which means that the orbits of these moons are affected by each other. As time goes on, these orbits stretch out and grow. 
 
 So, based on that logic, the younger moons should have different, more ordinary orbits than the older moons, if they actually had billions of years to get weird. As SETI puts it: 
 
 "By comparing present orbital tilts and those predicted by computer simulations, the researchers could learn how much the orbits of Saturn’s moons grew. It turns out that for some of the most important satellites - Tethys, Dione, and Rhea - the orbits are less dramatically altered than previously thought." 
 
 With that observation, the researchers used data from NASA’s Cassini mission data to create simulations. 
 
 When all was said and done, the team found that many of Saturn’s moons - except the faraway ones like Titan - likely formed 100 million years ago, meaning that many of Saturn’s moons formed during Earth’s Cretaceous Period, the era during which many of your favourite dinosaurs were alive. 
 
 It's hoped that the findings will help us judge the ages of other moons inside our Solar System and out. 
 
 It’s pretty crazy to think that moons were forming in our Solar System during a time on Earth that many of us can actually envision. It’s still a super-long time ago, but, cosmically speaking, it's like it only happened yesterday. 
 
 You can read the full research article in the Astrophysical Journal. 

 MOUNTAIN VIEW – New research suggests that some of Saturn’s icy moons, as well as its famous rings, might be modern adornments. Their dramatic birth may have taken place a mere hundred million years ago, more recent than the reign of many dinosaurs. 
 
 “Moons are always changing their orbits. That’s inevitable,” says Matija Ćuk, principal investigator at the SETI Institute. “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 two percent of the planet’s history.” 
 
 While Saturn’s rings have been known since the 1600s, there’s still debate about their age. The straightforward assumption is that they are primordial – as old as the planet itself, which is more than four billion years. However, in 2012, French astronomers found that tidal effects – the gravitational interaction of the inner moons with fluids deep in Saturn’s interior – are causing them to spiral to larger orbital radii comparatively quickly. The implication, given their present positions, is that these moons, and presumably the rings, are recent phenomena. 
 
 The new paper finds that Saturn's moon Rhea and all other moons and rings closer to Saturn may be only 100 million years old. Outer satellites (not pictured here), including Saturn's largest moon Titan, are probably as old as the planet itself. Download full size image credit:NASA/JPL 
 
 Ćuk, together with Luke Dones and David Nesvorny of the Southwest Research Institute, used computer modeling to infer the past dynamic behavior of Saturn’s icy inner moons. While our own moon has its orbit around Earth to itself, Saturn’s many satellites have to share space with each other. All of their orbits slowly grow due to tidal effects, but at different rates. This results in pairs of moons occasionally entering so-called orbital resonances. These occur when one moon’s orbital period is a simple fraction (for example, one-half or two-thirds) of another moon’s period. In these special configurations, even small moons with weak gravity can strongly affect each other’s orbits, making them more elongated and tilting them out of their original orbital plane. 
 
 By comparing present orbital tilts and those predicted by computer simulations, the researchers could learn how much the orbits of Saturn’s moons grew. It turns out that for some of the most important satellites – Tethys, Dione and Rhea – the orbits are less dramatically altered than previously thought. The relatively small orbital tilts indicate that they haven’t crossed many orbital resonances, meaning that they must have formed not far from where they are now. 
 
 Saturn's moon Tethys, with its giant canyon Ithaca Chasma. We propose that Ithaca Chasma was opened by strong tidal forces millions of years ago when Tethys was in an orbital resonance with the neighboring moon Dione. Download full size image credit:NASA 
 
 But how long ago was their birth? Ćuk and his team used results from NASA’s Cassini mission to help answer this question. The Cassini spacecraft has observed ice geysers on Saturn’s moon Enceladus. Assuming that the energy powering these geysers comes directly from tidal interactions, and that Enceladus’ level of geothermal activity is more or less constant, then the tides within Saturn are quite strong. According to the team’s analysis, these would move the satellite by the small amount indicated by the simulations in only about 100 million years. This would date the formation of the major moons of Saturn, with the exception of more distant Titan and Iapetus, to the relatively recent Cretaceous Period, the era of the dinosaurs. 
 
 “So the question arises, what caused the recent birth of the inner moons?” asks Ćuk. “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.” 
 
 If this result is correct, Saturn’s bright rings may be younger than the heyday of the dinosaurs, and we are fortunate to witness them today. 
 
 The research is being published in the Astrophysical Journal. 
 
 Read the preprint at http://arxiv.org/abs/1603.07071 
 
 Final print at http://iopscience.iop.org/article/10.3847/0004-637X/820/2/97 (requires subscription to view) 

 A couple of neat things about Rhea -- a 2010 study found it has a tenuous atmosphere of oxygen and carbon dioxide that may be created by surface water ice decomposing due to radiation from plasma (ionized gas) from Saturn's magnetosphere. Also, that plasma appears to affect the surface , a 2012 study concludes. This could account for why small craters are erased on the surface of Rhea, Di Sisto suggests. 
 
 , at least when looking for vapor production that is too orders of magnitude smaller than what has been observed on Enceladus. "However, plume activity cannot be absolutely ruled out because it can be under the detection limit," Di Sisto wrote. Like Tethys, Dione is also brighter on its leading hemisphere than its trailing one. While Di Sisto did not suggest what process could be causing the craters to erase, Di Sisto did point out that Dione has a tenuous atmosphere ( as per a separate 2011 study .) 
 
 In the same study that looked at Mimas in 2011, the scientists of that study also concluded that Tethys has no plumes . When looking at Tethys in far ultraviolet light, a weird picture emerges; its leading hemisphere is brighter than the trailing hemisphere, according to Di Sisto. Also, its surface appears strangely porous. Perhaps it is being pummeled with material from Saturn's E ring. Or, there could be geologic activity that hasn't yet been detected by Cassini. 
 
 looked for plumes on Mimas and said in 2011 that their search was in vain, according to Di Sisto. Therefore, there must be some sort of lower-level geologic activity that is reshaping the surface. Since Mimas is among the moons that could have an icy subsurface ocean, perhaps there is something related to that in the interior causing the crater erasure on the outside, Di Sisto's team suggests. 
 
 While Iapetus has an old surface, astrophysicists have noticed that the leading side of the moon is dark, while the trailing side is brighter. While it's unclear what is causing this difference, some theories include internal processes or perhaps debris or dust material falling from other moons of Saturn, to the darker side of Iapetus. In 2010, a study suggested that both processes may be at work at once if the dark material is falling on the leading hemisphere, triggering a runaway global dispersement of water ice. 
 
 particularly from four parallel fractures ("tiger stripes") near the south pole, according to a 2006 study. Craters would be erased both by the plumes and some tectonic activity. Some of the material escapes Enceladus and populates Saturn's E ring, while the rest falls back on to the surface and erases craters, according to a 2010 study. 
 
 Something is erasing craters on several moons of Saturn. And here's the neat thing -- it's likely a different process for each moon studied, according to the authors who developed a model for it. The results are published in a new Icarus paper called "Surface ages of mid-size Saturnian satellites" led by Romina Di Sisto (part of the faculty of astronomy and geophysics at Universidad Nacional in Argentina). The authors compared their theoretical predictions with "crater counts" (from other scientists) of Cassini and Voyager images of several Saturn satellites and concluded there are fewer smaller craters than predicted. Here are some of the most likely crater-erasing processes on several moons of Saturn. The authors plan to continue their work with Titan and other Saturnian moons in the future. 
 
 A grand canyon called Ithaca Chasma cuts across the fact of Saturn’s moon Tethys in this image from NASA’s Cassini probe. Scientists think the canyon opened millions of years ago when Tethys was orbitally synced with sister moon Dione. 
 
 Some of the moons and icy objects orbiting Saturn may have formed less than 100 million years ago, while dinosaurs still roamed the Earth. 
 
 The idea that some of Saturn’s moons may be relatively modern stems from computer models that simulated the moons’ gravitational interactions and shifting orbital tilts over time. 
 
 ANALYSIS: Fog Detected on Surface of Saturn Moon Titan 
 
 SETI Institute astronomer Matija Cuk and colleagues conclude that the moons inferior to giant Titan are not primordial, and most likely formed in the last 2 percent of the planet’s 4.5 billion-year history. 
 
 Saturn hosts at least 62 moons, 53 of which are currently named. The tally doesn’t include the hundreds of small icy objects that comprise the planet’s rings. 
 
 Titan, Saturn’s largest moon (which is bigger than the planet Mercury), is the only moon in the solar system that has a thick atmosphere. 
 
 PHOTO: Saturn Moons Align (Almost) to Perfection 
 
 Though most of Saturn’s current moons may be relatively new, the models show the planet has always had hordes of orbital companions. 
 
 “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,” Cuk said in a statement. 
 
 The research is published in The Astrophysical Journal.
– Scientists may have overestimated how old Saturn's rings and moons are—by more than 4 billion years. In fact, the planet's rings and many of its 62 moons likely didn't form until dinosaurs were around to see it happen, Discovery reports. Researchers from the SETI Institute measured changes in the orbits of Saturn's moons and rings—caused by the tidal forces they constantly exert on each other—to create a computer model capable of mapping their histories, according to a press release. They figured out the orbits of the icy moons closer to the planet hadn't changed as much as would be expected had they formed along with the planet 4.5 billion years ago as previously believed. Conversely, the planet's rings were shifting too quickly to be that old. Instead, it's likely the moons and rings were created in the most recent 2% of Saturn's history—or about 100 million years ago—when older moons circling the planet crashed into each other. Dinosaurs roamed the Earth from about 230 million years ago to 66 million years ago, CNN reports. Researchers published their findings Thursday in the Astrophysics Journal. They hope to use them to figure out the ages of other moons in the Solar System. "It’s pretty crazy to think that moons were forming in our Solar System during a time on Earth that many of us can actually envision," Science Alert states. "Cosmically speaking, it's like it only happened yesterday." (NASA is baffled by red arcs on one of Saturn's moons.)