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Credits: NASA Science News

Titan's ice shell, which overlies a very salty ocean, varies in thickness around the moon.
Image Credit: NASA/JPL/SSI/Univ. of Arizona/G. Mitri/University of Nantes

Scientists analyzing data from NASA’s Cassini mission have found evidence of an ocean inside Saturn's largest moon, Titan, which might be as salty as the Earth's Dead Sea.(learn more)

Source: NASA Science News

NASA's Cassini spacecraft has spotted a gigantic hurricane swirling inside a mysterious, six-sided weather pattern known as "the hexagon" on Saturn.(read more)

Source: NASA Science News

Image credit: NASA/JPL-Caltech/Space Science Institute/Cornell.

NASA's Cassini spacecraft has provided the first direct evidence of small meteoroids crashing into Saturn's rings and breaking into streams of rubble. (read more)

Source: ESA News

Series of images tracking the development of Saturn’s giant storm.
Image credits: NASA/JPL-Caltech/Space Science Institute.

The heat-seeking capabilities of the international Cassini spacecraft and two ground-based telescopes have provided the first look at the aftermath of Saturn’s ‘Great Springtime Storm’. Concealed from the naked eye, a giant oval vortex is persisting long after the visible effects of the storm subsided. (read more)

Credit: ESA

Ring clumps and strands.
Image credits: NASA/JPL/Space Science Institute.

Clumpy particles in Saturn’s B-ring provide stark contrast to the delicately ordered ringlets seen in the rest of this view presented by the Cassini spacecraft.

Saturn’s B-ring is the largest and brightest of the gas giant’s rings, the outer portion of which is seen in the left side of this image.

The ring’s outside edge is influenced by meddling moon Mimas, which orbits the planet once for every two circuits the icy ring particles complete.

These periodic gravity perturbations are thought to compress the ring particles into clumps, while maintaining the ring’s well-defined outer edge.

Beyond the B-ring lies the Huygens gap, the widest dark void visible in this image, punctuated only by the bright Huygens ringlet. The 4800 km-wide Cassini Division separates the B-ring from the outermost A-ring, but itself is marked out with faint, concentric strands of ring material.

From Earth, the Cassini Division appears as a thin black gap in Saturn’s rings, but close-up views from spacecraft expose the delicate structures in fine detail.

This image was taken in visible light with the Cassini spacecraft narrow-angle camera on 10 July 2009 from a distance of 320 000 km from Saturn.

Cassini is a joint mission between ESA, NASA and ASI and has been in orbit around Saturn since 2004. It is now in its second extended mission phase, the Cassini Solstice Mission, which will continue until 2017. (read more)

Source: Cassini Solstice Mission

The atmosphere of Titan.
Image credits: NASA/JPL-Caltech/Space Science Institute

On June 7 Cassini made flyby to Titan at a distance of 959 km and imaged portions of the moon’s northwest quadrant with its radar instrument and continued investigations of areas near the equator where surface changes were detected in 2010. It also made some raw images images where the atmosphere can be seen like the image above taken in September 2011. (learn more)

Source: NASA

Titan and Saturn. Image credit: NASA/JPL-Caltech/Space Science Institute .

Saturn's largest moon, Titan, looks small here, pictured to the right of the gas giant in this Cassini spacecraft view.

Titan (3,200 miles, or 5,150 kilometers across) is in the upper right. Saturn's rings appear across the top of the image, and they cast a series of shadows onto the planet across the middle of the image.

The moon Prometheus (53 miles, or 86 kilometers across) appears as a tiny white speck above the rings in the far upper right of the image. The shadow cast by Prometheus can be seen as a small black speck on the planet on the far left of the image, between the shadows cast by the main rings and the thin F ring. The shadow of the moon Pandora also can be seen on the planet south of the shadows of all the rings, below the center of the image towards the right side of the planet. Pandora is not shown here.

This view looks toward the southern, unilluminated side of the rings from about 1 degree below the ringplane.

The image was taken with the Cassini spacecraft wide-angle camera on Jan. 5, 2012 using a spectral filter sensitive to wavelengths of near-infrared light centered at 752 nanometers. The view was acquired at a distance of approximately 426,000 miles (685,000 kilometers) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 20 degrees. Image scale is 23 miles (37 kilometers) per pixel on Saturn. The Cassini-Huygens mission is a cooperative project of NASA, 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, D.C. 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, Colo.

Source:Cassini Solstice Mission

Image credit: NASA/JPL

Tomorrow Cassini goes back to Titan to make the T-82 flyby close to Titan's south pole.

During this close Titan flyby, the composite infrared spectrometer (CIRS) performs a wide variety of observations, including limb sounding, and mapping of surface and atmospheric temperatures. Far-infrared limb sounding near closest approach reaches the most northerly latitude of the Solstice Mission. (75 degrees North) until 2015, providing insights into the transition of the northern polar circulation from spring to summer, and includes a search for possible condensates. The Visible and Infrared Mapping Spectrometer (VIMS) rides-along to detect clouds to monitor climatic changes after the equinox.T-82 is a dusk sector equatorial flyby across Titan's magnetic tail. Similar in geometry, but at a lower altitude (2,363 miles, or 3,803 kilometers) than T-78, Cassini will be able to provide a better characterization of the magnetotail by providing samples at different radial distances from the moon at a fixed local time.

Source: NASA/Cassini

Huge storm churning through the atmosphere in Saturn's northern hemisphere.
Image credit: NASA/JPL-Caltech/SSI

Scientists analyzing data from NASA's Cassini spacecraft now have the first-ever, up-close details of a Saturn storm that is eight times the surface area of Earth.

On Dec. 5, 2010, Cassini first detected the storm that has been raging ever since. It appears at approximately 35 degrees north latitude on Saturn. Pictures from Cassini's imaging cameras show the storm wrapping around the entire planet covering approximately 1.5 billion square miles (4 billion square kilometers).

The storm is about 500 times larger than the biggest storm previously seen by Cassini during several months from 2009 to 2010. Scientists studied the sounds of the new storm's lightning strikes and analyzed images taken between December 2010 and February 2011. Data from Cassini's radio and plasma wave science instrument showed the lightning flash rate as much as 10 times more frequent than during other storms monitored since Cassini's arrival to Saturn in 2004. The data appear in a paper published this week in the journal Nature.(read more)

Source: NASA/Cassini

Plumes spray water ice out of the surface of Enceladus.
Image credit: NASA/JPL/SSI.

Cassini spacecraft has discovered the best evidence yet for a large-scale saltwater reservoir beneath the icy crust of Saturn's moon Enceladus. The data came from the spacecraft's direct analysis of salt-rich ice grains close to the jets ejected from the moon.

Data from Cassini's cosmic dust analyzer show the grains expelled from fissures, known as tiger stripes, are relatively small and usually low in salt far away from the moon. But closer to the moon's surface, Cassini found that relatively large grains rich with sodium and potassium dominate the plumes. The salt-rich particles have an "ocean-like" composition and indicate that most, if not all, of the expelled ice and water vapor comes from the evaporation of liquid salt-water. The findings appear in this week's issue of the journal Nature.(read more)

Related link: ESA

Source: NASA News

False-color infrared image, obtained by Cassini spacecraft,
shows a powerful storm in Saturn's northern hemisphere.
Image credit: NASA/JPL/Univ. of Arizona.

NASA's Cassini spacecraft and a European Southern Observatory Very Large Telescope (VLT) tracked the growth of a giant early-spring storm in Saturn's northern hemisphere so powerful it stretches around the entire planet. The rare storm has been wreaking havoc for months and shot plumes of gas high into the planet's atmosphere.

Cassini's radio and plasma wave science instrument first detected the large disturbance, and amateur astronomers tracked its emergence in December 2010. As it rapidly expanded, its core developed into a giant, powerful thunderstorm. The storm produced a 3,000-mile-wide (5,000-kilometer-wide) dark vortex, possibly similar to Jupiter's Great Red Spot, within the turbulent atmosphere.

The dramatic effects of the deep plumes disturbed areas high up in Saturn's usually stable stratosphere, generating regions of warm air that shone like bright "beacons" in the infrared. Details are published in this week's edition of Science Magazine. (read more)

Links:

NASA Cassini Mission
ESO Science Release eso1116
NASA Science News

Source: NASA News

Artist's concept of the magnetic connection between Saturn and its moon Enceladus. Image credit: NASA/JPL/JHUAPL/University of Colorado/Central Arizona College/SSI

NASA is releasing the first images and sounds of an electrical connection between Saturn and one of its moons. The data collected by the agency's Cassini spacecraft enable scientists to improve their understanding of the complex web of interaction between the planet and its numerous moons. The results of the data analysis are published in the journals Nature and Geophysical Research Letters.

Scientists previously theorized an electrical circuit should exist at Saturn. After analyzing data that Cassini collected in 2008, scientists saw a glowing patch of ultraviolet light emissions near Saturn's north pole that marked the presence of  a circuit, even though the moon is 150,000 miles (240,000 kilometers) away from the planet.

The patch occurs at the end of a magnetic field line connecting Saturn and its moon Enceladus. The area, known as an auroral footprint, is the spot where energetic electrons dive into the planet's atmosphere, following magnetic field lines that arc between the planet's north and south polar regions. (read more)

Source: NASA/Cassini

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

Every day is a bad-air day on Saturn's largest moon, Titan. Blanketed by haze far worse than any smog belched out in Los Angeles, Beijing or even Sherlock Holmes's London, the moon looks like a dirty orange ball. Described once as crude oil without the sulfur, the haze is made of tiny droplets of hydrocarbons with other, more noxious chemicals mixed in. Gunk.

Icky as it may sound, Titan is really the rarest of gems: the only moon in our solar system with an atmosphere worthy of a planet. This atmosphere comes complete with lightning, drizzle and occasionally a big, summer-downpour style of cloud made of methane or ethane -- hydrocarbons that are best known for their role in natural gas.

Now, thin, wispy clouds of ice particles, similar to Earth's cirrus clouds, are being reported by Carrie Anderson and Robert Samuelson at NASA's Goddard Space Flight Center in Greenbelt, Md. The findings, published February 1 in Icarus, were made using the Composite Infrared Spectrometer (CIRS) on NASA's Cassini spacecraft.

Unlike Titan's brownish haze, the ice clouds have the pearly white appearance of freshly fallen snow. Their existence is the latest clue to the workings of Titan's intriguing atmosphere and its one-way "cycle" that delivers hydrocarbons and other organic compounds to the ground as precipitation. Those compounds don't evaporate to replenish the atmosphere, but somehow the supply has not run out (read more).

Source: NASA/JPL

NASA's Cassini spacecraft has captured images of lightning on Saturn. The images have allowed scientists to create the first movie showing lightning flashing on another planet.

After waiting years for Saturn to dim enough for the spacecraft's cameras to detect bursts of light, scientists were able to create the movie, complete with a soundtrack that features the crackle of radio waves emitted when lightning bolts struck. (read more)

Source: NASA / Jet Propulsion Laboratory

Though there are no plans to investigate whether Saturn's moon Titan has a Santa Claus, NASA's Cassini will zoom close to Titan's north pole this weekend.

The flyby, which brings Cassini to within about 960 kilometers (600 miles) of the Titan surface at 82 degrees north latitude, will take place the evening of Dec. 27 Pacific time, or shortly after midnight Universal Time on Dec. 28. (read more)

Source: NASA/JPL

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