1 The Solar System An Inventory

1 What is the Solar System? Answer: The system of objects in the solar neighborhood (near the Sun) The sun –Has a luminosity 4 x 10 8 as large as the second brightest object in the solar system (Jupiter) –Contains over 99.8% of the mass in the solar system So the solar system can be thought of as the Sun and some debris In the first part of this class, we will concentrate on the debris

1 Giant Planets Large –Mass –Radius Low density –Primarily gaseous –No solid surface Strong magnetic fields Many moons Many rings Two subclasses: –Gas Giants (H & He) –Ice Giants (H 2 0, NH 3, CH 4 )

1 Terrestrial Planets Close to the sun Small –Mass –Radius High density –Primarily rocky –Solid surface Weak magnetic field Few moons No rings

1 Satellites Do not orbit the sun, instead orbit objects which orbit the sun Come in many sizes and orientations Large ones can have geology and surfaces similar to planets Most orbits are prograde and eccentric

1 Ring Systems CompositionSize JupiterDustSmall grains SaturnWater ice< house size UranusCarbonaceousLarge particles Neptunedark, unknownunknown, small

1 Primitive bodies Asteroids –Radii <~ 500 km –Located primarily between Mars and Jupiter Comets –Do not look like comets most of the time –Originate in Kuiper Belt ( AU) Oort Cloud (10 4 AU) Pluto (KBO?)

1 Planetary Properties The following properties can be determined by direct observation 1.Orbit (Kepler’s laws) 2.Mass, and distribution (Kepler’s laws - satellites) 3.Size (distance, occultation, photometry) 4.Rotation rate and direction (features, lightcurve) 5.Shape (imaging, occultation, radar, lightcurve) 6.Temperature (in situ, blackbody spectrum) 7.Magnetic field (in situ, aurorae) 8.Surface composition (spectral reflectance) 9.Surface structure (imaging) 10.Atmospheric structure and composition (spectra)

1 Planetary Properties 2 Some properties can’t be observed directly, but can be inferred –Bulk composition From density –Internal structure Core diameter from gravity measurements Surface features, magnetic field Tables of planetary properties can be found in your book.

1 Summary of Semester Energy –Transport Conduction Convection Radiation –Sources Solar Gravitational Radioactive Decay Tidal and Ohmic Surfaces –Rocks and minerals Igneous Metamorphic Sedimentary –Features Tectonics Volcanism Atmospheric (Aeolian) Impact Craters Surface features (except impacts) are driven by energy, the more energy available, the more features there are.

1 Final Project On some aspect of planetary science Must include some physical calculations Steps: –Choose a review article from one of my books or Annual Reviews of Earth and Planetary Science (1/14) –Summarize the article (1/18), carefully pick an aspect of the paper that interests you – this is your project topic –Order possible interesting articles (you’ll need 4-6) for paper through interlibrary loan (ASAP) –Discuss possible topics with me (1/24) –Write an annotated bibliography of some of the papers you’ve chosen (1/31) –Prepare a presentation about your topic (including the calculations) –Write a paper about your topic (draft 2/14 and final 2/25)

1 Something cool – Iapetus

1 Homework, due Friday Read Chapter 1 Do homework #1 (on web) Look over to help pick topicwww.nineplanets.org