Lecture 4-21-08 - Mercury

Lecture 4-21-08 - Mercury - Geology 21 Lecture - Monday,...

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Geology 21  THE PLANETS Lecture - Monday, April 21, 2008 Mercury Closest to Sun Hottest Never visited by man Visited by Pioneer probe No atmosphere Siderial rotation - every 59 days ~1/3 diameter of Earth Densest planet / Core 3:1 Minimal magnetic field (so must have some molten material in core) Crust - ~200 km thick Mantle ~600 km thick Core ~  Magnetic field (minimal) - indicates some of its core is still in molten state (mostly molten iron) - 1.  to have magnetic field 2.  Must have molten material 3.  Must have something to conduct electricity 4.  Reasonably rapid rotation Difficult to observe in a telescope (due to small window of visibility in visual spectrum) So, viewed using radio waves (radio astronomy) Arecibo Observatory, Puerto Rico — 305m radio telescope — most powerful radio instrument on Earth — radar first determined the true rotation period of Mercury
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This note was uploaded on 10/19/2008 for the course GEO 21 taught by Professor Repka during the Spring '08 term at Saddleback.

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Lecture 4-21-08 - Mercury - Geology 21 Lecture - Monday,...

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