Note 20
Welcome to Saturn
Basic Background
* 6th planet from the sun (Jovian), 2nd most massive
* Named for the god of agriculture
* 9.5 AU from Sun (~ 1.5 trillion Km)
* It was first discovered in 1610 by Galileo, but
can be seen with naked eye
* Gravity is just slightly more than Earth’s
Basic Info cont...
* 1 Saturnian year equals 29.5 Earth yrs
* 1 Saturnian day = ~ 11 hours
* Saturn rotates so fast that it causes its poles to
flatten out and a bulge to form in the middle !
What about those rings?
* Saturn has an extensive ring system which is
formed by a 1000 individual rings.
* The rings appear to contain water ice & dust.
* The thickness of the rings ranges from 10 to
100 meters and the rings vary in brightness.
But wait, there's more about the rings...
* There are gaps between some rings caused by
small satellites pushing them apart
* Astronomers believe the rings developed from
particles from the break-up of small satellites.
* The space between the 2 main rings (A and B)
is called the Cassini division
* Rings are very thin (< 1 km thick) and each
particle is in independent orbit
What's it like on Saturn?
th
Dark – it is the 6 planet from the sun
Windy - The winds in Saturn's atmosphere
reach speeds up to 1800 kilometers per
hour!
Stormy - Astronomers see large white
spots (or clouds) on Saturn which they
believe are storms.
Cold – temps vary from ~ -300°F to -10° F
Internal Composition
* Atmosphere is mainly Hydrogen and
Helium (like the sun)
* As with Jupiter, the pressurized hydrogen
in Saturn's mantle produces electric
currents which create a strong magnetic
field around the planet.
What about moons?
* Has at least 30 moons, the largest of which is
Titan
* 11 moons were discovered by the Voyager
missions and 13 more
were recently discovered
by land-based
telescopes
More on Titan
Picture taken by
Voyager in1980 –
Titan was covered by
clouds
Picture taken by
Cassini in 2004.
Surface appears to be
young (no craters)
Could Titan be an Earth in
development?
* Titan is the largest of Saturn's satellites & 2nd
largest satellite in solar system,
* only one know to have a dense atmosphere
* chemistry in Titan's atmosphere may be
similar to what occurred in Earth's atmosphere
several billion years ago
* Titan's density appears to be about twice
that of water ice; it may be composed of
nearly equal amounts of rock and ice.