23Sep2012

 How Many Rings Does Saturn Have?

Saturn is known to be the only planet which has visible rings around it. If you want to find out how many rings Saturn has, go on reading.

The answer to this question is not that simple. You will also know many interesting things about this unique planet as we delve into it’s mysteries and look closely at Saturn’s makeup.

General Facts about Saturn

The name of Saturn is of Roman origin. In the religion of ancient Romans Saturnus was the major god who was in charge of agriculture and harvest. He is supposed to be equal to such gods from other myths as Cronus, Ninurta, and Shani. One of the days of the week, Saturday, is named after this planet.

Saturn stands the sixth from the Sun and is situated between Uranus and Jupiter. In the whole Solar System1 there is only one planet larger than Saturn. It is Jupiter. Saturn, Jupiter, Neptune and Uranus are gas planets, and together they are called the Jovian.

You may be surprised to know that Saturn would be able to float in water. Its density is 0.687 grams/cm3, while water on our planet has density of 1 gram/cm3. Saturn consists mostly of helium and hydrogen though it also has some heavy materials in the core. So you would not be able to stand on its surface.

Saturn’s radius is about nine times larger than the one that the Earth has. But it spins on its axis very quick. That is why its year is more than twenty nine Earth years long, but its day has no more than ten and a half hours.

Saturn Rings

As stated above, Saturn has a distinctive feature, which it is widely known for. Of course, we are talking about its ring system.

Though people discovered Saturn thousands years ago, they had not been able to see its rings because it is impossible without a telescope. In 1610, Galileo observed the rings but thought them to be Saturn’s two moons. Dutch astronomer Christian Huygens had a more advanced telescope than Galileo, so in 1655 he was able to scrutinize the planet thoroughly and espied the rings.

In fact, these rings are not solid. They are made of separate parts. As they reflect about 80% of the light, there is every reason for thinking that they are chunks of ice, though gravel, dust, rocks, and similar objects can also be among them. All these particles orbit the planet individually. Their size can vary from less than one millimeter to about twenty meters. It is interesting that every ring has its own atmosphere, separate from Saturn’s atmosphere.

There are several theories about the origin of Saturn rings. Some scientists think that they could be the remnants of the planet’s foundation. Others believe that long time ago the rings were Saturn’s moons.

How Many Rings Does Saturn Have?

The question about the exact number of Saturn rings is rather difficult, but scientists have been able to give answer to it. Latin letters are used to classify the main rings. Here are their short descriptions.

  • Ring A is very bright and outer-lying. It has its moon named Daphnis orbiting inside it.

  • Ring B is the largest and densest of all Saturn rings.

  • Ring C is very faint.

  • Ring D is located closest to Saturn and is hard to see.

  • Ring E is a very wide and outer-lying ring made of ice chunks.

  • Ring F has the unique spiral strand around it. It is the farthest ring from Saturn.

  • Ring G is situated between rings F and E. It is small and hardly visible.

  • Ring O was discovered in 2010. Now it is supposed to be the largest ring.

As you can see, now we can talk about eight Saturn rings. But there is also the Phoebe ring, which was also discovered not long time ago. This ring has got a backwards orbit and is tilted a bit.

But the above mentioned objects are not the only Saturn rings, because this planet has also some divisions and gaps in them. The most widely-known of them are the Cassini Division2, the Janus Ring, the Anthe Ring Arc, the Methone Ring Arc, the Pallene Ring, and the Roche Division. So if we take into account all of them, we will get more than thirty rings.

But even now nobody can say for sure that people have been able to see all Saturn rings. Most probably, there are still more of them. Source:1howmany.com

 

Saturn and its Largest Moon Reflect Their True Colors

A giant of a moon appears before a giant of a planet undergoing seasonal changes in this natural color view of Titan and Saturn from NASA's Cassini spacecraft.

Posing for portraits for NASA’s Cassini spacecraft, Saturn and its largest moon, Titan, show spectacular colors in a quartet of images being released today. One image captures the changing hues of Saturn’s northern and southern hemispheres as they pass from one season to the next.

A wide-angle view in today’s package captures Titan passing in front of Saturn, as well as the planet’s changing colors. Upon Cassini’s arrival at Saturn eight years ago, Saturn’s northern winter hemisphere was an azure blue. Now that winter is encroaching on the planet’s southern hemisphere and summer on the north, the color scheme is reversing: blue is tinting the southern atmosphere and is fading from the north.

The other three images depict the newly discovered south polar vortex in the atmosphere of Titan, reported recently by Cassini scientists. Cassini’s visible-light cameras have seen a concentration of yellowish haze in the detached haze layer at the south pole of Titan since at least March 27. Cassini’s visual and infrared mapping spectrometer spotted the massing of clouds around the south pole as early as May 22 in infrared wavelengths.

Artist's conception of Cassini–Huygens as it e...

After a June 27 flyby of the moon, Cassini released a dramatic image and movie showing the vortex rotating faster than the moon’s rotation period. The four images being released today were acquired in May, June and July of 2012.

Some of these views, such as those of the polar vortex, are only possible because Cassini’s newly inclined — or tilted — orbits allow more direct viewing of the polar regions of Saturn and its moons.

Scientists are looking forward to seeing more of the same — new phenomena like Titan’s south polar vortex and changes wrought by the passage of time and seasons — during the remainder of Cassini’s mission.

“Cassini has been in orbit now for the last eight years, and despite the fact that we can’t know exactly what the next five years will show us, we can be certain that whatever it is will be wondrous,” said Carolyn Porco, imaging team lead based at the Space Science Institute in Boulder, Colo.

Launched in 1997, Cassini went into orbit around Saturn on July 1, 2004. It is in its second mission extension, known as the Solstice Mission, and one of its main goals is to analyze seasonal changes in the Saturn system.

“It is so fantastic to experience, through the instruments of Cassini, seasonal changes in the Saturn system,” said Amanda Hendrix, deputy project scientist, based at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “Some of the changes we see in the data are completely unexpected, while some occur like clockwork on a seasonal timescale. It’s an exciting time to be at Saturn.”

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens 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 team is based at the Space Science Institute in Boulder, Colo.

Source: Jet Propulsion Laboratory, Pasadena, Calif.