NATS_3-26 - NATS Terrestrial Planet Geology and Atmospheres...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
NATS March 26, 2009 - Terrestrial Planet Geology and Atmospheres o Why so different? Terrestrial planets all formed out of similar material: rock and metal Their surfaces look very different Why? - A Look Inside o Drills can penetrate about 1% of the Earth’s interior depth o Seismic waves traveling through the Earth can reveal the interior composition o The waves will refract or diffract depending on the type of material (and how much) they encounter as they travel through the Earth o Other planets can be probed less directly (although we do measure seismic waves on the Moon too) o Satellites can also measure the gravitational field of planets at different places, and piece together the density structure that way o Earth: The liquid outer core bends P waves  But stops S waves  - Basic Structure o Core Highest density material, made of heavy metals like Iron, Nickel, Platinum, etc. May be liquid and/or solid. On Earth, the “inner core” is solid, and is surrounded by a liquid “outer core” o Mantle Rocky material surrounding the core, made of minerals like quartz. Because the deep mantle is under pressure and is
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
at higher temperature, it is “softer” than layer above it, and can deform and “flow” (similar to glaciers) o Crust Outer layer, made of lower density rocks like granite and basalt o Lithosphere The rigid rock layer that floats on the softer rock beneath. Usually includes the crust and part of the mantle. o Planets like Earth, Venus, Mars have all of these components, but at different ratios - Differentiation o Densest material inside: why? o Piece of iron atop piece of ice: what happens? Nothing would happen. It’s just like stacking blocks. o Liquid iron dropped into liquid water: what happens? Would sink to the bottom o Liquids differentiate: gravity pulls denser material to the bottom (against buoyancy) o Earth and other terrestrial planets must have been hot enough to melt! -
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/07/2009 for the course NATS 006 taught by Professor Eisner during the Spring '09 term at Arizona.

Page1 / 8

NATS_3-26 - NATS Terrestrial Planet Geology and Atmospheres...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online