ASTRONOMY 8850: Planetary Sciences

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ASTRONOMY 8850Planetary Sciences

• Why Sciences?

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How to do well inPlanetary Sciences

• 1. show up to class
• 2. participate in class
• 3. get/borrow the book Planetary Sciences by de
  Pater and Lissauer
• 4. find course website www.chara.gsu.edu/thenry/
  PLANETS
• 5. get a three-ring binder dividers
• 6. find Icarus online or in the library
• 7. choose planetary topic(s) you are most
  interested in --- start project EARLY
• 8. do homework --- Solar System Explorer,
  quizzes, etc.

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Solar System Explorers 01

• Find Icarus online or in the library.
• Choose an article of interest to you.
• Print out the first page of the article.
• Turn in single page (with your name on it) at the
  beginning of class WEDNESDAY.
• Get first 5 points in Solar System Explorer.

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Solar System Inventory

• stars
• planets
• moons
• ring systems
• minor planets
• Kuiper Belt Objects
• comets
• and

• 1
• 8
• 165 (as of 2009 JAN 11)
• 41
• 436,000a (as of 2008 DEC 12)
• 1,300 (as of 2009 JAN 11)
• 152,000b (as of 2008 DEC 15)
• dust
• a with orbits
• b periodic and numbered

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Nomenclature

• terrestrials
• Mercury, Venus, Earth, Mars
• many moons
• jovians
• gas giants
• Jupiter, Saturn
• ice giants
• Uranus, Neptune
• minor planets
• asteroids
• Centaurs
• Kuiper Belt Objects
• Trans-Neptunian Objects (TNOs)
• Plutinos
• Scattered Disk Objects (SDOs)
• comets

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Solar Family
How are they different?
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Planet Spacing
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Planet Orbits
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The Giants
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The 7 Dwarfs ( interlopers)
X
X
X
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Terrestrial Planet Surface
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Surface Variability
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Jovian Planet Surface
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we can land/work on surfaces
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Planet Characteristics
Characteristic Terrestrial
Jovian

• location
• spacing
• mass
• size
• density
• composition
• surface
• albedo
• rotation
• magnetics
• moons
• rings

• 0.4-1.5 AU 5.2-30.1 AU
• close wide
• 0.05-1.0 Earths 14.5-318
  Earths
• 0.4-1.0 Earth radii 3.9-11.2 Earth
  radii
• 3.9-5.5 g/cm3 0.7-1.6 g/cm3
• rocky gaseous
• solid any?
• 0.1-0.7 0.4-0.5
• slow fast
• none/weak strong
  (integrated)
• none/few many
• none all

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obliquities (tilts)
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bizarre bar magnets
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magnetospheres
Earths is strongest terrestrial surface
mag field 0.3 G mag moment 8x1025
G/cm3 enough to protect us from
charged particles Mercurys, Ganymedes
wimpy Venus?, Io, Europa, Callisto induced Mars
patchy crustal
Jupiters is strongest jovian surface mag
field 4.3 G mag moment 20000X Earths
Io plasma torus complicates
affects all Galilean satellites Sat/Ura/Nep
surface mag fields similar strength to Earths
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Jupiters magnetotail
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non-trends in the Solar System

• surface gravities not radically different
• obliquities do not behave
• 7 large moons are worlds of their own
• Moon, Io, Europa, Ganymede, Callisto,
  Titan, Triton

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Asteroids

• Ceres

Vesta
Eros
Itokawa
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Asteroids 2003semimajor axis
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Asteroids 2009semimajor axis
Trojans Mars has 4 Jupiter has 2910 Neptune has 6
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Absolute Magnitude H V magnitude if 1 AU from
Earth and 1 AU from Sun while having phase angle
of 0 degrees (an impossible scenario) H 16
means diameter of 2-4 km
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ASTEROIDS green dots normal
m.p. red dots lt 1.3 AU periastron filled gt 1
opposition obs. blue dots Jupiter Trojans
COMETS solid blue sqr numbered open
blue sqr others
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ASTEROIDS green dots normal
m.p. red dots lt 1.3 AU periastron filled gt 1
opposition obs. blue dots Jupiter Trojans
COMETS solid blue sqr numbered open
blue sqr others
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KBOs and Comets 2003
KBOs red classical KBOs white
Plutinos magenta scattered disk orange tri
Centaurs cyan tri unusual
COMETS solid blue sqr numbered open blue squ
others
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KBOs and Comets 2009
KBOs red classical KBOs white
Plutinos magenta scattered disk orange tri
Centaurs cyan tri unusual
COMETS solid blue sqr numbered open blue squ
others
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KBOs and Comets 2009
Plutinos/TNOs 1093 known Pluto Quaoar Ixion Varu
na Orcus Centaurs/SDOs 242 known Chiron Sedna N
essus Asbolus Eris
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TNOs/SDOs and Friends
Hydra
Nix
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The Outer Limits
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Disk Protostellar or Debris?
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Fomalhaut Planet
background star
movie
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