Page 48 - Ultimate Visual Dictionary (DK)

THE UNIVERSE

Saturn TILT AND ROTATION OF SATURN

Axial tilt of 26.7° One rotation
takes 10 hours
SATURN IS THE SIXTH PLANET from the Sun. It is a and 40 minutes
gas giant almost as big as Jupiter, with an equatorial
North
diameter of about 75,000 miles (120,500 km). Saturn
Pole
is thought to consist of a small core of rock and ice Orbital
plane
surrounded by an inner mantle of metallic hydrogen
(liquid hydrogen that acts like a metal). Outside the
inner mantle is an outer mantle of liquid hydrogen
FALSE-COLOR
IMAGE OF SATURN that merges into a gaseous atmosphere. Saturn’s
South Pole
clouds form belts and zones similar to those on
Jupiter, but obscured by overlying haze. Storms and eddies, seen as Perpendicular Axis of
rotation
red or white ovals, occur in the clouds. Saturn has an extremely thin to orbital plane
but wide system of rings that is about half a mile (1 km) thick but
extends outward to about 260,000 miles (420,000 km) from the
FALSE-COLOR IMAGE OF SATURN’S
planet’s surface. The main rings comprise thousands of narrow
CLOUD FEATURES
ringlets, each made of icy rock lumps that range in size from tiny
particles to chunks several yards across. The D, E, and G rings are Ribbon-shaped
striation caused
very faint, the F ring is brighter, and the A, B, and C rings are by winds of 335
bright enough to be seen from Earth with binoculars. In 2009, mph (540 km/h)
a huge dust ring was discovered 4 million miles (6 million km)
beyond the main system. Saturn has more than 60 known moons,
Oval (rotating
some of which orbit inside the rings and are thought to exert a storm system)
gravitational influence on the shapes of the rings. Unusually, seven
of the moons are co-orbital—they share an orbit with another
moon. Astronomers believe that such co-orbital moons may have
originated from a single satellite that broke up.

INNER RINGS OF SATURN MOONS OF SATURN
D ring
C ring (“crepe ring”)
B ring
Cassini Division
A ring
Encke
Division ENCELADUS TETHYS
Diameter: 509 miles Diameter: 652 miles
F ring Average distance from Average distance from
planet: 148,000 miles planet: 183,000 miles

DIONE MIMAS
Diameter: 695 miles Diameter: 247 miles
Average distance from Average distance from
planet: 254,000 miles planet: 115,600 miles