What creates a planetary magnetic field?

1. Metallic material in the core

2. (a) Fluid Motion of the core

OR

(b) Rapidly Rotating planet

What benefit is a magnetic field?- Protects the planet from atmosphere stripping solar winds.

Mercury-Roman god of Travel

Mercury - Basic InformationNo Atmosphere

Very Weak Magnetic Field (1% of Earth’s)

Rotates 3 times for every 2 revolutions

Temperature variations: Shadow: -300F Sunlight: 800F

Highly Elliptical Orbit 29 million miles to 43 million miles

Mercury TransitThe planet passes in front of the Sun.

ME-S-S-EN-GE-RMercury Surface Space Environment Geochemistry and Ranging

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Water Ice -Found in Permanent Shadows of craters.

VenusRoman god of Love

Venus - Basic Information

Revolves once every 243 Earth Days

Rotates once every 224 Earth Days

Thick CO2 atmosphere (100 times thicker than Earth’s)

Surface Temperature = 900F

Venus - Basic Information

Runaway Greenhouse Effect

No moons

No magnetic field

No plate tectonics

Venera SpacecraftRussian - First landing on another planet.

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MarsRoman god of War

MarsHalf the size of the Earth

Mars - basic info

Atmosphere 1% as thick as Earth

Mostly CO2

Temperatures can range from

-200 F up to 70 F

No magnetic field

Mars Exploration-1970’s: Viking Landers -1980’s: Numerous failed missions -1996: Pathfinder Rover -2004: Mars Exploration Rovers (Spirit & Opportunity) -2008: Mars Phoenix Lander -2012: Mars Science Laboratory (Curiosity)

Anatomy of a Mars LandingCompare three different approaches

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Water in Mars’ past?

CONFIRMED

MarsSubsurface salty water may still exist on Mars

Mars’ Methane Enigma

Mars has 2 small moons: