Jovian Planets

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A) Jupiter

1) Named after Roman king of the gods

2) Twice as massive as all the other planets in the solar system combined

3) Hydrogen-based gases

4) Slightly more dense than water 1.1 g/cm3

5) Surface features

(a) Alternating bands of clouds that spin in opposite directions

(1) Caused by material rising from and falling to the interior of the planet

(i) Zones white bands

(ii) Belts dark bands

(2) Coriolis effect

(i) Winds spin in opposite directions

(b) Giant Red Spot

(1) Permanent hurricane

(c) No real surface

(1) Clouds become denser and eventually turn into liquid

6) Gives off twice the energy it receives

(a) Residual heat from the formation of the planet

7) Many moons

(a) Formed similar to solar system

(1) Small, rocky moons formed towards the interior

(2) Larger, lighter moons formed further out

(b) Galilean moons

(1) Io

(i) Extremely volcanically active

(ii) Produces sulfur making surface look orange-red

(2) Europa

(i) Icy crust covered in epsom salts

1. Cracked due to interior volcanic activity

2. Interior liquid core

3. Life could exist

(3) Ganymede

(i) Largest moon in solar system

(ii) Larger than Mercury

(4) Callisto

(i) Similar to Ganymede

8) Planetary ring system

9) Differential rotation

(a) Equator spins faster than the poles

(1) Only a planet essentially made of gas can do this

(2) All Jovian planets exhibit this behavior


Interior of Jupiter

Great Red Spot

Jupiter & Moons





  Jupiter's Rings Jupiter's Magnetic Field  

B) Uranus

1) Named for Roman god of the sky

2) Discovered by observations by Sir William Herschel

(a) Noticed a disk-shaped object

(b) Two large to be a star

3) Relatively feature-less plant

4) Lack of cloud bands

(a) Rotation on axis in plane of orbit

(1) Spins with north or south pole facing Sun

(i) Impact of large object pushed Uranus onto side

(b) Lack of dynamic weather pattern

5) Moons

(a) Named after characters in Shakespearean plays


Uranus' Moons & Rings

Uranus' Moons

Shepherd moons of Uranus' Rings


The most interesting moon geologically is Miranda, shown on the left. Even though it is only 500 km in diameter, it shows surface geological features that are as varied as any site in the Solar System.  It is not clear why Miranda has been so active geologically. Some theories include tidal heating effects earlier in its history; or a collision that tore it apart and allowed it to coalesce again. None are very conclusive.

C) Saturn

1) Named after the Roman god of the harvest

2) Almost as large as Jupiter, less than one-third the mass

(a) Would float in a large enough ocean

3) Lacks striking band colors due to cold temperatures

4) Exterior frozen ammonia clouds

5) Interior similar to Jupiter

6) Complex ring system

(a) Rocks and ice

(b) Moon within the Roche Limit

(1) Pulled apart due to gravitational forces

(c) Captured satellites broken apart

(d) Cassini division

(1) Gap in the rings

(2) Shepherding satellites

(e) 50,000 miles across and 200 yards deep

7) Moons

(a) Over 20

(1) Titan

(i) One of two moons in solar system with an atmosphere

For an animation of Saturn's ring system and surface storms, click hereNote: Large file.


Saturn's Rings

Moons of Saturn


D) Neptune

1) Named after the Roman god of the sea

2) Approximately same size as Uranus

3) Radically different atmosphere

(a) Dynamic surface

(1) Winds in excess of 1000 miles per hour

(b) Blue Spot

(1) Similar to Red Spot on Jupiter

(2) Discovered by Voyager Probe

(3) 1998 pictures from Hubble telescope show spot had disappeared, but it has since reappeared

4) Moons

(a) Triton mermen

(1) Only other moon with an atmosphere

(b) Nereid mermaids


For an animation of the rotation of Neptune, click here. Note: large file.

Neptune - the blue spot is a storm, similar to storm seen on Jupiter.  The storm on Neptune disappeared in 1998, but has since reappeared.

Neptune's Rings (black bar is leg of camera in way of the camera lens.)

E) Pluto

1) Not a Jovian planet ("plutonian" or "dwarf planet")

2) Named after the Roman god of underworld

3) Discovered by Claude Tombaugh in 1930 at Lowell Observatory, Flagstaff, Arizona - click here for pictures.

4) Moons

(a) Charon ferryman over the Styx (river of the dead)

     (1) Discovered recently James Christy (1978)

     (2) Tidally locked - same sides face each other

(b) Hydra - serpent guarding the waters of the underworld

(c) Nix - goddess of darkness and mother of Charon

     (1) Nix and Hydra are based on the initials of the New Horizons mission that

          will visit the Plutonian system in 2015

5) Presumed to be made of frozen gases and water

(a) Similar to most comets

(b) Remnant left over from the formation of the solar system

6) Coldness would force water to have the consistency of steel

7) Very elliptical orbit

(a) Inclined to the plane at 17

(b) Occasionally closer to sun than Neptune

For an animation of Pluto's rotation, click hereNote: Large file.


Pluto (left) & Charon (right)

Surface Map of Pluto

Plutonian System

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