One planet, two planets, three planets, four! Comparing the terrestrial worlds
Looking to do research? Modeling astrophysical disks Work with LASP researcher Glen Stewart to develop and run numerical models of planetary rings and protoplanetary disks. Requirements: Interest in data modeling Knowledge of C (IDL, Python also preferred) Contact:
A host of worlds, big and small
Why compare the planets? Understand the diversity of worlds Use knowledge of one to extend that of others Planets are cool
Four agents of change
Erosion Impacts Volcanism Tectonics
Peering deep with density BodyRadius (km)Mass / Mass of EarthDensity (kg/m^3) Mercury Venus Earth Moon Mars MaterialDensity (kg/m^3) Iron7874 Granite2600 Water1000
Peering deep with density
Map of Mercury
Radar map of Venus
Map of Earth
Map of the Moon
Map of Mars
The impact of impacts Impacts are vital to measuring ages in the solar system
The impact of impacts Even when ages are uncertain (usually!), craters reveal relative age of a surface Young Old
Water, water everywhere Mars Yemen
Lava flows are snapshots in time MarsHawaii
So are landslides… Mars Mexico
Envelopes of gas BodyAtmospheric density (bar) Primary constituents Mean temperature (K) Mercury H, He, Na452 Venus92CO 2, N730 Earth1N, O287 Moon Ar, He220 Mars0.006CO 2, Ar, N226 Titan1.5N, CH 4 94
Creating an atmosphere Ways to generate an atmosphere:
Creating an atmosphere Ways to generate an atmosphere: Primordial Outgassing Delivery of volatiles Life
Stripping an atmosphere Ways to lose an atmosphere:
Stripping an atmosphere Ways to lose an atmosphere: Escape to space All worlds Collapse to surface Stripped by solar wind Mercury Moon Mars
Moons are a planet’s best friend BodyMoonsMoon mass / planet mass Mercury0- Venus0- Earth Mars21.9x10 -8 Jupiter632.1x10 -4 Saturn612.5x10 -4 Uranus271x10 -4 Neptune142.1x10 -4 Pluto50.12
Putting it all together Planetary properties are the constraints for modeling solar system formation
What would you do? Question: If you could return a sample from one place in the solar system, where would you go? Body Feature type Justification