1. The Terrestrial Planets

2. Exploration of Mercury

3. Mercury Half-Mapped

5. Mercury’s Orbit Fairly eccentric with e=0.21 –Perihelion distance = 0.31 AU –Aphelion distance = 0.47 AU Resonance –So Mercury rotates 3 times for every 2 orbits around the Sun –This is a tidal effect from the Sun

6. The Mercurian Day

7. Advance of Mercury’s Orbit

8. General Properties of Mercury Temperature –100 K at night to 700 K by day Magnetic Field –Surprisingly strong at ~0.5% of Earth’s –Magnetic field and high average density suggest a large iron core Atmosphere –None Interior –Large iron core - 1/3 by volume, extending to about 70% of radius

10. Degas Impact crater about 45 km wide Imaged by the Mariner 10 flybys

11. Surface Effects Scarps are seen on Mercury. Useful for relative dating and history of the surface.

12. Caloris Basin

13. Interior of Mercury

14. Origin Model for Mercury