Saturn

 

 

Saturn

 

 

 

Click on the small images for a larger one.

 

Saturn is the second largest planet. Only Jupiter is larger. Saturn has seven thin, flat rings around it. The rings consist of numerous narrow ringlets, which are made up of ice particles that travel around the planet. The gleaming rings make Saturn one of the most beautiful objects in the solar system. Jupiter, Neptune, and Uranus are the only other planets known to have rings. Their rings are much fainter than those around Saturn.

Saturn's diameter at its equator is about 74,900 miles (120,540 kilometers), almost 10 times that of Earth. The planet can be seen from Earth with the unaided eye, but its rings cannot. Saturn was the farthest planet from Earth that the ancient astronomers knew about. They named it for the Roman god of agriculture.

Saturn travels around the sun in an elliptical (oval-shaped) orbit. Its distance from the sun varies from about 941,070,000 miles (1,514,500,000 kilometers) at its farthest point to about 840,440,000 miles (1,352,550,000 kilometers) at its closest point. The planet takes about 10,759 Earth days, or about 29 1/2 Earth years, to go around the sun, compared with 365 days, or one year, for Earth.

 

Click here for larger imageRotation

As Saturn travels around the sun, it spins on its axis, an imaginary line drawn through its center. Saturn's axis is not perpendicular (at an angle of 90 degrees) to the planet's path around the sun. The axis tilts at an angle of about 27 degrees from the perpendicular position.

Saturn rotates faster than any other planet except Jupiter. Saturn spins around once in only 10 hours 39 minutes, compared to about 24 hours, or one day, for Earth. The rapid rotation of Saturn causes the planet to bulge at its equator and flatten at its poles. The planet's diameter is 8,000 miles (13,000 kilometers) larger at the equator than between the poles.

 

Surface and atmosphere

Most scientists believe Saturn is a giant ball of gas that has no solid surface. However, the planet seems to have a hot solid inner core of iron and rocky material. Around this dense central part is an outer core that probably consists of ammonia, methane, and water. A layer of highly compressed, liquid metallic hydrogen surrounds the outer core. Above this layer lies a region composed of hydrogen and helium in a viscous (syruplike) form. The hydrogen and helium become gaseous near the planet's surface and merge with its atmosphere, which consists chiefly of the same two elements.

A dense layer of clouds covers Saturn. Photographs of the planet show a series of belts and zones of varied colors on the cloud tops. This banded appearance seems to be caused by differences in the temperature and altitude of atmospheric gas masses.

The plants and animals that live on Earth could not live on Saturn. Scientists doubt that any form of life exists on the planet.

 

Temperature

The tilt of Saturn's axis causes the sun to heat the planet's northern and southern halves unequally, resulting in seasons and temperature changes. Each season lasts about 7 1/2 Earth years, because Saturn takes about 29 times as long to go around the sun as Earth does. Saturn's temperature is always much colder than Earth's, because Saturn is so far from the sun. The temperature at the top of Saturn's clouds averages -285 degrees F (-175 degrees C).

The temperatures below Saturn's clouds are much higher than those at the top of the clouds. The planet gives off about 2 1/2 times as much heat as it receives from the sun. Many astronomers believe that much of Saturn's internal heat comes from energy generated by the sinking of helium slowly through the liquid hydrogen in the planet's interior.

 

Density and mass

Saturn has a lower density than any other planet. It is only about one-tenth as dense as Earth, and about two-thirds as dense as water. That is, a portion of Saturn would weigh much less than an equal portion of Earth, and would float in water.

Although Saturn has a low density, it has a greater mass than any other planet except Jupiter. Saturn is about 95 times as massive as Earth. The force of gravity is a little higher on Saturn than on Earth. A 100-pound object on Earth would weigh about 107 pounds on Saturn.

 

Cassini Spacecraft Captures Images and Sounds of Big Saturn Storm

07.06.11

PASADENA, Calif. – 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).

Click HereThe 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.

"Cassini shows us that Saturn is bipolar," said Andrew Ingersoll, an author of the study and a Cassini imaging team member at the California Institute of Technology in Pasadena, Calif. "Saturn is not like Earth and Jupiter, where storms are fairly frequent. Weather on Saturn appears to hum along placidly for years and then erupt violently. I'm excited we saw weather so spectacular on our watch."

At its most intense, the storm generated more than 10 lightning flashes per second. Even with millisecond resolution, the spacecraft's radio and plasma wave instrument had difficulty separating individual signals during the most intense period. Scientists created a sound file from data obtained on March 15 at a slightly lower intensity period.

Cassini has detected 10 lightning storms on Saturn since the spacecraft entered the planet's orbit and its southern hemisphere was experiencing summer, with full solar illumination not shadowed by the rings. Those storms rolled through an area in the southern hemisphere dubbed "Storm Alley." But the sun's illumination on the hemispheres flipped around August 2009, when the northern hemisphere began experiencing spring.

"This storm is thrilling because it shows how shifting seasons and solar illumination can dramatically stir up the weather on Saturn," said Georg Fischer, the paper's lead author and a radio and plasma wave science team member at the Austrian Academy of Sciences in Graz. "We have been observing storms on Saturn for almost seven years, so tracking a storm so different from the others has put us at the edge of our seats."

The storm's results are the first activities of a new "Saturn Storm Watch" campaign. During this effort, Cassini looks at likely storm locations on Saturn in between its scheduled observations. On the same day that the radio and plasma wave instrument detected the first lightning, Cassini's cameras happened to be pointed at the right location as part of the campaign and captured an image of a small, bright cloud. Because analysis on that image was not completed immediately, Fischer sent out a notice to the worldwide amateur astronomy community to collect more images. A flood of amateur images helped scientists track the storm as it grew rapidly, wrapping around the planet by late January 2011.

 

Swirling Storms on Saturn

11.28.12

 

Click HereNASA's Cassini spacecraft has been traveling the Saturnian system in a set of inclined, or tilted, orbits that give mission scientists a vertigo-inducing view of Saturn's polar regions. This perspective has yielded images of roiling storm clouds and a swirling vortex at the center of Saturn's famed north polar hexagon.

These phenomena mimic what Cassini found at Saturn's south pole a number of years ago. Cassini has also seen storms circling Saturn's north pole in the past, but only in infrared wavelengths because the north pole was in darkness.  But, with the change of the Saturnian seasons, the sun has begun to creep over the planet's north pole.

This particular set of raw, unprocessed images was taken on Nov. 27, 2012, from a distance of about 250,000 miles (400,000 kilometers) from Saturn.

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

 

Rings

The rings of Saturn surround the planet at its equator. They do not touch Saturn. As Saturn orbits the sun, the rings always tilt at the same angle as the equator.

Click HereThe seven rings of Saturn consist of thousands of narrow ringlets. The ringlets are made up of billions of pieces of ice. These pieces range from ice particles that are the size of dust to chunks of ice that measure more than 10 feet (3 meters) in diameter.

Saturn's major rings are extremely wide. The outermost ring, for example, may measure as much as 180,000 miles (300,000 kilometers) across. However, the rings of Saturn are so thin that they cannot be seen when they are in direct line with Earth. They vary in thickness from about 660 to 9,800 feet (200 to 3,000 meters). A space separates the rings from one another. Each of these gaps is about 2,000 miles (3,200 kilometers) or more in width. However, some of the gaps between the major rings contain ringlets.

Saturn's rings were discovered in the early 1600's by the Italian astronomer Galileo. Galileo could not see the rings clearly with his small telescope, and thought they were large satellites. In 1656, after using a more powerful telescope, Christiaan Huygens, a Dutch astronomer, described a "thin, flat" ring around Saturn. Huygens thought the ring was a solid sheet of some material. In 1675, Giovanni Domenico Cassini, an Italian-born French astronomer, announced the discovery of two separate rings made up of swarms of satellites. Later observations of Saturn resulted in the discovery of more rings. The ringlets were discovered in 1980.


Classic Trails or Mini-Jets
April 24, 2012

This set of six images obtained by NASA's Cassini spacecraft shows trails that were dragged out from Saturn's F ring by objects about a half mile (1 kilometer) in diameter. Scientists have seen more than 500 of these kinds ofClick Here trails in over 20,000 images collected by Cassini from 2004 to 2011. The trails seen in this set are typical of the entire collection. From left to right in the top row, the trails in these images are 18, 85 and 96 miles long (29, 136 and 155 kilometers long). In the bottom row from left to right, the trails are 43, 129 and 32 miles long (69, 207 and 51 kilometers long).

The trails are also called "mini-jets" by Cassini scientists. Scientists believe they were originally formed by the pull of the moon Prometheus, which averages about 53 miles or 86 kilometers across, on tiny F ring particles.

As Prometheus works its way around Saturn, its gravitational attraction sometimes parts channels in the icy particles of Saturn's F ring and sometimes pushes together sticky snowballs. The moon's continued progress around Saturn pulls some of the snowballs apart over time and adds material to others. These trails appear to be the telltale signs of surviving, evolved snowballs that strike through the F ring on their own. Scientists have been able to use Cassini images to track the objects and be sure they have different orbits from the F ring. The collisions occur at gentle speeds, on the order of 4 mph (2 meters per second). The F ring is the outermost of Saturn's main rings, with a radius of about 87,129 miles (140,220 kilometers).

 

Satellites

In addition to its rings, Saturn has 33 satellites that measure at least 6 miles Some of Saturn's Moons kilometers) in diameter, and several smaller satellites. The largest of Saturn's satellites, Titan, has a diameter of about 3,200 miles (5,150 kilometers) -- larger than the planets Mercury and Pluto. Titan is one of the few satellites in the solar system known to have an atmosphere. Its atmosphere consists largely of nitrogen.

Many of Saturn's satellites have large craters. For example, Mimas has a crater that covers about one-third the diameter of the satellite. Another satellite, Iapetus, has a bright side and a dark side. The bright side of this satellite reflects about 10 times as much sunlight as the dark side. The satellite Hyperion is shaped somewhat like a squat cylinder rather than like a sphere. Unlike Saturn's other satellites, Hyperion's axis does not point toward the planet. Saturn has at least 52 moons total.

 

Cassini Finds a Video Gamers' Paradise at Saturn

11.26.12

 

You could call this "Pac-Man, the Sequel." Scientists with NASA's Cassini mission have spotted a second feature shaped like the 1980s video game icon in the Saturn system, this time on the moon Tethys. (The first was found on Mimas in 2010). The pattern appears in thermal data obtained by Cassini's composite infrared spectrometer, with warmer areas making up the Pac-Man shape.

"Finding a second Pac-Man in the Saturn system tells us that the processes creating these Pac-Men are more widespread than previously thought," said Carly Howett, the lead author of a paper recently released online in the journal Icarus. "The Saturn system - and even the Jupiter system - could turn out to be a veritable arcade of these characters."

Click hereScientists theorize that the Pac-Man thermal shape on the Saturnian moons occurs because of the way high-energy electrons bombard low latitudes on the side of the moon that faces forward as it orbits around Saturn. The bombardment turns that part of the fluffy surface into hard-packed ice. As a result, the altered surface does not heat as rapidly in the sunshine or cool down as quickly at night as the rest of the surface, similar to how a boardwalk at the beach feels cooler during the day but warmer at night than the nearby sand. Finding another Pac-Man on Tethys confirms that high-energy electrons can dramatically alter the surface of an icy moon. Also, because the altered region on Tethys, unlike on Mimas, is also bombarded by icy particles from Enceladus' plumes, it implies the surface alteration is occurring more quickly than its recoating by plume particles.

"Studies at infrared wavelengths give us a tremendous amount of information about the processes that shape planets and moons," said Mike Flasar, the spectrometer's principal investigator at NASA's Goddard Space Flight Center in Greenbelt, Md. "A result like this underscores just how powerful these observations are."

Scientists saw the new Pac-Man on Tethys in data obtained on Sept. 14, 2011, where daytime temperatures inside the mouth of Pac-Man were seen to be cooler than their surroundings by 29 degrees Fahrenheit (15 kelvins). The warmest temperature recorded was a chilly minus 300 degrees Fahrenheit (90 kelvins), which is actually slightly cooler than the warmest temperature at Mimas (about minus 290 degrees Fahrenheit, or 95 kelvins). At Tethys, unlike Mimas, the Pac-Man pattern can also be seen subtly in visible-light images of the surface, as a dark lens-shaped region. This brightness variation was first noticed by NASA's Voyager spacecraft in 1980.

"Finding a new Pac-Man demonstrates the diversity of processes at work in the Saturn system," said Linda Spilker, Cassini project scientist at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "Future Cassini observations may reveal other new phenomena that will surprise us and help us better understand the evolution of moons in the Saturn system and beyond."

Image credit: NASA/JPL-Caltech/GSFC/SWRI

 

 

Dark and Arc

 

June 27, 2016

 

Saturn's arc

At first glance, the most obvious features in this image from NASA's Cassini spacecraft are 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.

 

In this view, icy Enceladus (313 miles or 504 kilometers across) hangs in the space between Cassini and the giant planet.

This view looks toward the sunlit side of the rings from 0.14 degrees above the ring plane. The image was taken in visible light with the Cassini spacecraft wide-angle camera on Aug. 18, 2015.

The view was acquired at a distance of approximately 87,000 miles (139,000 kilometers) from Enceladus. Image scale is 5 miles (8 kilometers) per pixel.

 

 

 

Rings Interrupted

 

Click for bigger imageJune 6, 2016

 

Distant Titan, its northern hemisphere drenched in the sunlight of late spring, hangs above Saturn's rings.  What might at first glance look like a gap between the rings and the planet is actually Saturn’s shadow.  During most of Saturn's long year, the projection of the planet's shadow extends well beyond the edge of the A ring.  But, with summer solstice fast approaching, the Sun is now higher in Saturn's sky and most of Saturn's A ring is completely shadow-free.

This view looks toward the sunlit side of the rings from about 3 degrees above the ring plane. The image was taken in red light with NASA's Cassini spacecraft wide-angle camera on Jan. 26, 2016.

 

 

 

 

 

 

For more on the Saturn moons click HERE!

 

 

Flights to Saturn

In 1973, the United States launched a space probe to study both Saturn and Jupiter. This craft, called Pioneer-Saturn, sped by Jupiter in 1974 and flew within 13,000 miles (20,900 kilometers) of Saturn on Sept. 1, 1979. The probe sent back scientific data and close-up photographs of Saturn. The data and photographs led to the discovery of two of the planet's outer rings.

CassiniPioneer-Saturn also found that the planet has a magnetic field, which is 1,000 times as strong as that of Earth. This field produces a large magnetosphere (zone of strong magnetic forces) around Saturn. In addition, data from the probe indicated the presence of radiation belts inside the planet's magnetosphere. The belts consist of high-energy electrons and protons, and are comparable to Earth's Van Allen belts.

In 1977, the United States launched two space probes -- Voyager 1 and Voyager 2 -- to study Saturn and other planets. Voyager 1 flew within 78,000 miles (126,000 kilometers) of Saturn on Nov. 12, 1980. On Aug. 25, 1981, Voyager 2 flew within 63,000 miles (101,000 kilometers) of the planet.

The Voyager probes confirmed the existence of Saturn's seventh ring. They also found that the planet's rings are made up of ringlets. In addition, the probes sent back data and photographs that led to the discovery or confirmation of the existence of nine satellites. The Voyager probes also determined that the atmosphere of Titan consists chiefly of nitrogen. In 1997, the United States launched the Cassini probe to study Saturn, its rings, and its satellites. The probe began orbiting Saturn in 2004. Cassini also carried a probe called Huygens, which was to separate from Cassini and land on Titan. Huygens was built by the European Space Agency, an organization of European nations.

 

Contributor: Hyron Spinrad, Ph.D., Professor of Astronomy, University of California, Berkeley.

 

 

Click here for larger image

Comparing Saturn to Earth

Comparing Saturn and Earth

 

 

 

 

 

Click on the images below for a larger one.

 

Click Here

 

 

 

Click here for a larger image

Click here for a larger image

Click here for larger image

New image from Cassini

Click here for a larger image

Satrun's South Pole -- New from Cassini

Saturn's North Pole -- New from Cassini

 

 

 

 

 

Saturn's Satellites

Solarsystem Main Page

 

 
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*

*
*
*
*
*
*
*
*
*
*
*

*
*
*
*
*
*
*
*
*
*
*

*
*
*
*
*
*
*
*
*
*
*

*
*
*
*
*
*
*
*
*
*
*

*
*
*
*
*
*
*
*
*
*
*

*
*
*
*
*
*
*
*
*
*
*

*
*
*
*
*
*
*
*
*
*
*

*
*
*
*
*
*
*
*
*
*
*

*
*
*
*
*
*
*
*
*
*
*

*
*
*
*
*
*
*
*
*
*
*

*
*
*
*
*
*
*
*
*
*
*

*
*
*
*
*
*
*
*
*
*
*

 

 



  The Future Astronauts of America Foundation



Promote Your Page Too

 

 

 

 


 

 

 

 

 

 

The Future Astronauts of America Foundation Title; 'We help launch the future' slogan; Character and Name Ikky;
and The
Future Astronauts of America Foundation Logo are intellectual property of The Future Astronauts of America Foundation