Jovian Planets & Dwarf Planets(Chapter 18)
Student Learning Objectives
• Identify & describe each Jovian planet
• Compare and contrast the Jovian planets
• Characterize PlutoPluto & Charon
What are the basic qualities of Jovian planets?
Jovian planets are often called gas or ice giants.
Contain mostly low density materialsNo solid surfaceSeveral moonsRing systemsHydrogen rich atmospheres
Practice
What is the most likely method for Jovian planets to have acquired atmosphere? Explain.
a. Outgassing c. Comets
b. Volcanism d. Capture
How are Jupiter and Saturn similar?
Deep layers contain liquid and metallic hydrogen
Strong magnetic fields
Alternating bands of belts and zones in atmosphere
Jupiter 20,000x Earth'sSaturn 8,000x Earth's
Jupiter
Rotation
Rotation Periods average 10 h
Non-solid objects have different rotation speeds at different latitudes.
Differential Rotation
Fluid Spinning Fast Oblate
The smaller the core, the more oblate the shape
Jupiter Saturn
Jupiter & Saturn
The Galilean Moons• Io (P = 1.769 days)
• Europa (P = 3.551 days)• Ganymede (P = 7.154 days)• Callisto (P = 16.689 days)
The Great Red Spot
on Jupiter
is the longest lived weather disturbance in the
solar system.
The Red Spot is ShrinkingMay 15, 2014 NASA
Jupiter’sRing
Practice
1) Who was the first person to “see” the Galilean moons? Why was observing these moons important?
2) Why is it difficult to observe Jupiter’s ring?
Saturn's ring system is divided into 7 major systems.
Each major system is comprised of several ringlets.
Saturn’s Rings
Saturn’s Moon Titan
Saturn's largest moon, Titan, has an atmosphere and liquid methane lakes.
Practice
1) How did Saturn get it’s rings?
2) Why would scientists want to explore methane lakes on Titan?
How are Uranus and Neptune similar?
Uranus and Neptune both have methane rich atmospheres.
Uranus looks green-blue
Neptune looks very blue
Uranus & Neptune
Uranus Neptune
Uranus and Neptune both have ring systems.
Uranus’sRings
Neptune’sRings
Uranus rotates on its side (90º Tilt), resulting in the most extreme seasons in our solar system.
Neptune’s Spot
Neptune has the strongest winds (1,200 mph) ever recorded on any planet.
The Great Dark Spot
on Neptune
Disappeared in 1994
APODMay 8, 1996
Practice
1) Why do you think Neptune is more blue than Uranus?
2) Write a general statement discussing how Uranus and Neptune compare and contrast with Jupiter and Saturn.
Pluto is unlike either Terrestrial or Jovian planets.
Orbit is inclined by 17ºOrbit is elliptical (e = 0.25)Composition similar to comet
Pluto is characterized as a
dwarf planet.
What about Pluto?
Plutobefore New Horizons
Image Credit: NASA
Definition of a Planet(2006, International Astronomical Union)
1. Is in orbit around the Sun
2. Has sufficient mass to assume a nearly round shape
3. Is not a satellite (moon)
4. Has cleared the neighborhood around its orbit
Dwarf Planets
Dwarf planets are defined as objects that are similar to planets but do not meet all planet criteria.
CeresPluto Eris
Practice
1) What criterion is Pluto missing to be classified as a planet?
2) How many moons does Pluto have?
Hubble Finds 'Tenth Planet' Slightly Larger Than Pluto
04.11.06 NASA
Pluto’s Moons
NASA
Space.com