Plume Zoom Flying over Enceladus' southern plumes (click to play) Check this piece of coolness out… it’s an animation made of 30 frames of raw image data captured by Cassini during its August 13th flyby of Enceladus. It shows the little moon’s signature ice plumes erupting from fissures in the surface of its south pole as the spacecraft approaches. Neato!!! Enceladus' Icy Geysers I saw it on The Boston Globe’s September 15th Big Picture post which featured a bunch of great images from current space science missions, but I haven’t found out yet where the original animation was published. (If it’s not animating just give it a click. :) ) Image: NASA/JPL/Space Science Institute Like this post? Like this: Like Loading...
Pac-Man Seen Near Saturn - Space News November 26, 2012 Image Caption: Scientists with NASA's Cassini mission have spotted two features shaped like the 1980s video game icon "Pac-Man" on moons of Saturn. One was observed on the moon Mimas in 2010 and the latest was observed on the moon Tethys. Image credit: NASA/JPL-Caltech/GSFC/SWRI Lee Rannals for redOrbit.com — Your Universe Online NASA announced on Monday its Cassini spacecraft has helped to discover a “video gamers’ paradise” at Saturn. The space agency said scientists have spotted a second feature shaped like the 1980s video game icon Pac Man in the Saturn system on the moon Tethys. “Finding a second Pac-Man in the Saturn system tells us that the processes creating these Pac-Men are more widespread than previously thought,” Carly Howett, the lead author of a paper recently released online in the journal Icarus, said in a statement. The altered surface does not heat as rapidly in the sunshine or cool down as quickly at night as the rest of the surface, according to NASA.
Saturn's Moon Phoebe - Solar System Reference Library Saturn’s moon Phoebe — Phoebe is the outermost of Saturn’s known moons. Phoebe is almost 4 times more distant from Saturn than its nearest neighbor (Iapetus). It was discovered by William Henry Pickering in 1898. Most of Saturn’s moons have very bright surfaces, but Phoebe’s albedo is very low (.06), as dark as lampblack. Phoebe’s orbit is retrograde, inclined almost 175, and is highly eccentric. Phoebe is also unusual in that it does not rotate synchronously as all the other moons of Saturn except Hyperion do. All this suggests that it may be a captured asteroid with a composition unmodified since the time it was formed in the outer Solar System. Since they are so small they never heated up sufficiently to change chemical composition. Material knocked off of Phoebe’s surface by microscopic meteor impacts may be responsible for the dark surfaces of Hyperion and the leading hemisphere of Iapetus. Discovery Discovered by William Henry Pickering Discovered in 1898 Orbital characteristics
Saturn's Shockwaves Reach Supernova Force Scientists are particularly interested in "quasi-parallel" shocks, where the magnetic field and the "forward"-facing direction of the shock are almost aligned, as may be found in supernova remnants. The new study, led by Masters describes the first detection of significant acceleration of electrons in a quasi-parallel shock at Saturn, coinciding with what may be the strongest shock ever encountered at the ringed planet. Shock waves are commonplace in the universe, for example in the aftermath of a stellar explosion as debris accelerate outward in a supernova remnant, or when the flow of particles from the sun - the solar wind - impinges on the magnetic field of a planet to form a bow shock. Under certain magnetic field orientations and depending on the strength of the shock, particles can be accelerated to close to the speed of light at these boundaries. The Daily Galaxy via NASA Image credit: Coutersy NASA/JPL
"Saturn's Ring System Rains Water into Atmosphere" --(Featured News Story) O'Donoghue said the ring's effect on electron densities is important because it explains why, for many decades, observations have shown electron densities to be unusually low at some latitudes at Saturn. "The ring particles affect which species of particles are in this part of the atmospheric temperature." In the early 1980s, images from NASA's Voyager spacecraft showed two to three dark bands on Saturn and scientists theorized that water could have been showering down into those bands from the rings. Those bands were not seen again until 2011 when the the team observed the planet with Keck Observatory's NIRSPEC, a unique, near-infrared spectrograph that combines broad wavelength coverage with high spectral resolution, allowing the observers to clearly see subtle emissions from the bright parts of Saturn. What they observed instead was a series of light and dark bands with a pattern mimicking the planet's rings. This is a significantly larger area than suggested by the Voyager images.
Possible Subsurface Ocean Beneath Saturn Moon Dione - Space News May 30, 2013 Image Credit: The Cassini spacecraft looks down, almost directly at the north pole of Dione. The feature just left of the terminator at bottom is Janiculum Dorsa, a long, roughly north-south trending ridge. Credit: NASA/JPL/Space Science Institute Brett Smith for redOrbit.com – Your Universe Online Once considered to be an afterthought when it came to Saturn´s moons, scientists now believe Dione likely had an active geological history after analyzing data sent back from NASA´s Cassini spacecraft. “A picture is emerging that suggests Dione could be a fossil of the wondrous activity Cassini discovered spraying from Saturn’s geyser moon Enceladus or perhaps a weaker copycat Enceladus,” said Cassini team leader Bonnie Buratti of NASA’s Jet Propulsion Laboratory in Pasadena, California. Cassini´s images suggest that Dione could join Saturn’s other moons that are believed to have subsurface activity, Enceladus and Titan. Source: Brett Smith for redOrbit.com - Your Universe Online
Astrophile: Saturn's egg moon Methone is made of fluff - space - 17 May 2013 Astrophile is our weekly column on curious cosmic objects, from the solar system to the far reaches of the multiverse Object: Oval moon MethoneLocation: Saturn's rings Out among Saturn's menagerie of moons, a shiny white egg rests in a nest of ice crystals. Named Methone, this small, oval moon was seen in close-up for the first time last year by NASA's Cassini spacecraft. Objects in our solar system have been battered by asteroids and comets for billions of years, but planets and big moons have ways of smoothing themselves out. Small moons, though, are geologically inactive and airless, so are unable to erase the damage. Clutch of lunar eggs In fact, this 5-kilometre-wide moon is one of a clutch of space eggs, all orbiting Saturn in the same region between the larger moons Mimas and Enceladus. Each moon lies within its own ring arc, a fragmentary ring of Saturn. . Thomas and his colleagues at Cornell have now attempted to crack the egg and look inside – by calculating Methone's density.
Salt in Enceladus geyser points to liquid ocean - space - 29 April 2009 THE ice plumes that bloom above Saturn's icy moon Enceladus are almost certainly rooted in a subsurface sea of liquid water. The Cassini spacecraft flew through a plume on 9 October 2008 and measured the molecular weight of chemicals in the ice. Frank Postberg of the Max Planck Institute for Nuclear Physics in Heidelberg, Germany, and colleagues, found traces of sodium in the form of salt and sodium bicarbonate. The chemicals would have originated in the rocky core of Enceladus, so to reach a plume they must have leached from the core via liquid water. Observations from Earth in 2007 spotted no sign of sodium, casting doubt on such a subsurface sea. Although the salt could have been leached out by an ancient ocean which since froze solid, that freezing process would concentrate most of the salt very far from the surface of the moon's ice, ...
Saturn may have snagged Pluto's cousin, turned it into a moon Saturn's moon Phoebe might be a planetesimal—a remnant of the rocky building blocks of the planets in our Solar System. A new study by Julie C. Castillo-Rogez et al. from Cassini spacecraft data indicates that Phoebe dates back to the very earliest days of the Solar System. Based on surface features and evidence that the moon is significantly more dense than the larger Saturnian satellites, the astronomers argue that Phoebe likely formed much farther from the Sun then fell inward, where it was snagged by Saturn's gravity. Using detailed observations from Cassini and Earth-based telescopes, in combination with detailed computer simulations, Castillo-Rogez et al. determined that Phoebe began as a spherical body. Based upon the density and comparison with bodies of similar size, Phoebe may have a rocky core surrounded by a porous icy shell. Phoebe's orbit is retrograde, meaning it circles in the opposite direction to Saturn's other moons, as well as the planet's rotation.
Cassini detects hint of fresh air at Dione | Popular Mechanics Nasa's Cassini spacecraft has "sniffed" molecular oxygen ions around Saturn's icy moon Dione for the first time, confirming the presence of a very tenuous atmosphere. The oxygen ions are quite sparse – one for every 11 cubic centimetres of space or about 90 000 per cubic metre – show that Dione has an extremely thin neutral atmosphere. At the Dione surface, this atmosphere would only be as dense as Earth's atmosphere 480 kilometres above the surface. The detection of this faint atmosphere, known as an exosphere, is described in a recent issue of the journal Geophysical Research Letters. "We now know that Dione, in addition to Saturn's rings and the moon Rhea, is a source of oxygen molecules," said Robert Tokar, a Cassini team member based at Los Alamos National Laboratory and the lead author of the paper. Dione's oxygen appears to derive from either solar photons or energetic particles from space bombarding the moon's water ice surface and liberating oxygen molecules, Tokar said.
Image of the Day --NASA Finds Vast River System on Saturn's Moon Titan Titan has been considered a “unique world in the solar system” since 1908 when, the Spanish astronomer, José Comas y Solá, discovered that it had an atmosphere, something non-existent on other moons. It seems perfectly appropriate that one of the prime candidates for life in our solar system, Saturn's largest moon, should have surface lakes, lightning, shorelines, relatively thick nitrogen atmosphere, seasons, and now, a vast river system. "Though there are some short, local meanders, the relative straightness of the river valley suggests it follows the trace of at least one fault, similar to other large rivers running into the southern margin of this same Titan sea," said Jani Radebaugh, a Cassini radar team associate at Brigham Young University, Provo, Utah. "Such faults - fractures in Titan's bedrock -- may not imply plate tectonics, like on Earth, but still lead to the opening of basins and perhaps to the formation of the giant seas themselves." mage credit: NASA/JPL-Caltech/ASI
Oxygen detected on Saturn's moon Rhea | Science A spacecraft has tasted oxygen in the atmosphere of another world for the first time while flying low over Saturn's icy moon, Rhea. Nasa's Cassini probe scooped oxygen from the thin atmosphere of the planet's moon while passing overhead at an altitude of 97km in March this year. Until now, wisps of oxygen have only been detected on planets and their moons indirectly, using the Hubble space telescope and other major facilities. Instruments aboard Cassini revealed an extremely thin oxygen and carbon dioxide atmosphere that is sustained by high-energy particles slamming into the moon's surface and kicking up atoms, molecules and ions. Astronomers have counted 62 moons orbiting Saturn. "This really is the first time that we've seen oxygen directly in the atmosphere of another world," said Andrew Coates, at UCL's Mullard Space Science Laboratory, a co-author of the study published in the journal Science. Rhea's atmosphere makes it unique in the Saturn system.
Saturn's largest moon was once a titanic snowball - space - 18 June 2014 Saturn's hazy moon Titan may sometimes morph into a ball of ice. Titan is already a frigid moon made mostly of ice. But methane gas in its atmosphere causes just enough of a greenhouse effect to keep a scattering of lakes filled with liquid hydrocarbons. Scientists have puzzled over Titan's atmospheric methane because sunlight causes the molecule to react readily with other chemicals in the air, producing the moon's dense smog. Clear the air Adding to the mystery, the methane reactions create hydrocarbon compounds that rain over the surface. Michael Wong at the California Institute of Technology says snowballs may be the missing piece of the puzzle. A similar event could have taken place on Titan, says Wong. Pluto proxy But how would this explain the moon's missing ocean? Getting good enough readings of the surface composition to check this would require a future mission to Titan. "Like Titan, Pluto has an atmosphere that is mostly nitrogen with some methane," says Wong. More from the web
Hot Cyclones Churn At Both Ends Of Saturn Despite more than a decade of winter darkness, Saturn's north pole is home to an unexpected hot spot remarkably similar to one at the planet's sunny south pole. The source of its heat is a mystery. Now, the first detailed views of the gas giant's high latitudes from the Cassini spacecraft reveal a matched set of hot cyclonic vortices, one at each pole. While scientists already knew about the hot spot at Saturn's south pole from previous observations by the W. "We had speculated that the south pole hot spot was connected to the southern, sunlit conditions," said Glenn Orton, a senior research scientist at NASA's Jet Propulsion Laboratory, Pasadena, Calif., and co-investigator on Cassini's composite infrared spectrometer. The infrared data show that the shadowed north pole vortex shares much the same structure and temperature as the one at the sunny south pole. Though similar, the two polar regions differ in one striking way. Winter lasts about 15 years on Saturn.