The Composition of Saturn

Like Jupiter, Saturn contains hydrogen, helium, ammonia, and methane. However, 88% of the mass of Saturn is composed of hydrogen with 11% helium, the two lightest elements on the periodic table.

Saturn has a diameter of 9.42 times that of Earth and a mass that is 95.15 times that of Earth. Despite being so much larger than Earth, these properties lead to a strange phenomena. Saturn's density is only 0.69 g/cm³. Water has a density of 1.0 g/cm³. Yes, Saturn has a lower density than water. What this means that if you could construct a large enough tank and filled it with water, Saturn would float in that tank. No other planet has a density of less than 1.0 g/cm³, though there are some satellites that have low densities.

Saturn is also banded, but not to the extent as Jupiter. Since it is farther away, the clouds are not as brightly illuminated as they are on Jupiter. Also, the ammonia ice crystals in the atmosphere of Saturn are above the cloud layers, preventing light from reaching the clouds, and help make the clouds darker than otherwise. Of course, Saturn's gorgeous rings make up for the blandness of its atmosphere.

The Banded Atmosphere of Jupiter

Infrared and Visible Light Image of the Bands of Jupiter 

Image Credit:

NASA

One of the most striking features when you look at images of Jupiter is that the atmosphere is not homogeneous, but banded. The Jovian planets are the only planets that display this feature, though Jupiter's is the most pronounced.

The bands are regions of high pressure, rising gas and low pressure, sinking gas separated by high winds. The bands that have high pressure, rising gas are called zones. The zones are bright but cold. They are made up of ice particles that are either ammonia or water ice. The darker bands, called belts, are low pressure, thin clouds that are sinking towards the planet. The belts do not reflect as well as the zones, so appear darker in comparison. The high winds separating the bands are called jets, travel along lines of latitude (east-west), and blow in either the prograde direction or retrograde direction. The prograde jets travel along with the direction of rotation of the Jupiter (from west to east) and the retrograde jets travel against the direction of rotation (east to west). The prograde jets are the transitions from zones to belts (as you move away from Jupiter's equator) and the retrograde jets transition from belts to zones..

The zones and belts are distinct on the surface of Jupiter. Just like Earth, Jupiter has distinct temperature regions based on their location on the planet. They are named as follows:

• The Equatorial Zone: as the name implies, this is the zone at the equator. Its range is from 7°S to 7°N.
• The North and South Equatorial Belts: the belts just north and south of the Equatorial Zone. They are reddish in color and range from 7°N (S) to 18°N (S).
• The North and South Tropical Zones: the South Tropical Zone is where the Great Red Spot is located
• The North and South Temperate Belts: the South Temperate Belt contains Oval BA (Red Jr.)
• The North and South Temperate Zones
• The N-N and S-S Temperate Belts
• The N-N and S-S Temperate Zones
• The North and South Polar Regions

A description of the belts and zones

Image Credit:

Sky and Telescope



 

The jets between the zones and belts travel at over 100 m/s (360 kph or 224 mph) and keep the bands from mixing.