MercuryMercury

MercuryMercuryassembled by images from Mariner 4 (1974)assembled by images from Mariner 4 (1974)

VenusVenus

Venus’ Runaway Greenhouse Venus’ Runaway Greenhouse EffectEffect

Atmosphere:Atmosphere:

Thick -90 barsThick -90 bars

CO2CO2

Some N, othersSome N, others

Temp: 730KTemp: 730K

= 850 F= 850 F

Venus ExplorationVenus Exploration

Fly-bys since 1962Fly-bys since 1962

Probes since 1970Probes since 1970

Orbiters since 70’s – Orbiters since 70’s – use radar studiesuse radar studies

Magellan – Venus Magellan – Venus orbiter - 1989orbiter - 1989

The Atmosphere of VenusThe Atmosphere of Venus

Venus – albedo = 80%Venus – albedo = 80%

Clouds – Sulfuric AcidClouds – Sulfuric Acid

Geology of VenusGeology of Venus

500 MA – Intense 500 MA – Intense VolcanismVolcanism

Rolling plains with 2 Rolling plains with 2 highland areashighland areas

Visible volcanic Visible volcanic depositsdeposits

Torn crust, ridges and Torn crust, ridges and cracks cracks Tectonic Tectonic ForcesForces

MarsMars

The Red PlanetThe Red Planet

StatisticsStatistics

1.5 AU from Sun1.5 AU from Sun

Orbit: 687 earth-daysOrbit: 687 earth-days

Rotation: 24.5 hoursRotation: 24.5 hours

Color: Reddish (iron in soil)Color: Reddish (iron in soil)

Density: lowDensity: low

Diameter = half of Earth’sDiameter = half of Earth’s

Magnetic Field – noneMagnetic Field – none

Cratered Surface of MarsCratered Surface of Mars

Cratering Period from 3 – 4 GACratering Period from 3 – 4 GA

Water on MarsWater on Mars

Mars’ VolcanoesMars’ Volcanoes

Olympus MonsOlympus Mons

Tharsis AreaTharsis Area

Valles MarinerisValles Marineris

5000 km long5000 km long

Formed by pressure from belowFormed by pressure from below

Shaped by water and windShaped by water and wind

Mars’ SurfaceMars’ Surface

Iron in soilIron in soil

Why not in core?Why not in core?

Atmosphere of MarsAtmosphere of Mars

Storms on MarsStorms on Mars

Dust Storm and Cyclonic StormDust Storm and Cyclonic Storm

Satellites of MarsSatellites of Mars

Phobos and DeimosPhobos and Deimos

Life on Mars?Life on Mars?

Exploration of MarsExploration of Mars

Fly-bys since 1965Fly-bys since 1965

Orbiter in 1971Orbiter in 1971

Viking 1 and Viking 2 Viking 1 and Viking 2 – Landed in 1976– Landed in 1976

Rovers Spirit and Rovers Spirit and Opportunity – still Opportunity – still goinggoing