Mars, Mercury, Titan and Vesta

Crater Rim on Mars

We can Drill on Mars

View From the Top

Opportunity’s Heat Shield

Spirit Makes Tracks

Layering on Mars

Layered Rocks Up Close

Recent Water on Mars?

Martian Glacier?

Descent of Phoenix

Polar Landscape

Mercury: We’re B-a-a-ck

Mercury’s Rotation For a Long Time, Astronomers Believed Mercury Was Locked to the Sun One Side Perpetually Sunlit (And Hot!) Other Side Perpetually Dark (And Cold!) In 1965, Radio Observations Showed Mercury’s Night Side Was Warm Mercury Rotates 3 Times for Every Two Orbits of the Sun

Tidal Friction

Mercury’s Rotation

How Did We Get It So Wrong? Mercury is Hard to Observe Not Much to See from Earth Earth, Mercury and Sun Repeat Same Relative Positions Every 116 Days 116 Days = Two Rotations For Years, An Astronomer Observing at the Best Times Sees The Same Face!

Mercury’s Interior Density = 5.43 (Earth = 5.5) Much smaller than Earth, less pressure inside Core about 2/3 of Mercury’s diameter (Earth = ½) Mega-Impact may have blown away silicate outer part For a Tiny Planet, Has Strong Magnetic Field (1% o Earth’s)

Massive Objects Can Speed Up or Slow Down Less Massive Objects

Gravity Assist to Speed Up

Gravity Assist to Slow Down

Mercury from Mariner 10, 1973

Mercury has Craters Not as dense as on Moon Most of Mercury covered with lava plains (intercrater plains)

Mercury has a huge impact basin, the Caloris Basin

Chaotic Terrain

Fault Scarps

Because of Mercury’s locked rotation, it has two “hot poles”

And Mercury has the last thing you’d expect to find: ice caps

Mercury’s ice seems to be hiding in polar craters

Messenger MErcury Surface, Space ENvironment, GEochemistry and Ranging August 3, 2004 -- MESSENGER Launch August 2005 -- Earth flyby October 2006 -- Venus flyby June 2007 -- Venus flyby January 2008 -- Mercury flyby October 2008 -- Mercury flyby September 2009 -- Mercury flyby March 2011 -- Orbit of Mercury

Visit to Earth

Visit to Earth

Exciting Venus

Venus Flyby

We’re B-a-a-ck

“Spider” Crater

Caloris Basin

Volcano on Mercury?

Saturn From Cassini

Crescent Saturn

Behind Saturn

Behind Saturn You Are Here

Ripply Rings

Making Waves

Phoebe

Iapetus By Saturn-Shine

Iapetus Ridge

Titan’s Haze

Surface of Titan

Aerial View of Titan

Surface of Titan

Dunes on Titan

Lakes on Titan

Titan’s Largest Sea

Sun Glint off Liquid

Boris Smeds: The Hero of Huygens

Ceres and Vesta

Dawn to Vesta and Ceres First Mission to use ion propulsion First Mission to main belt asteroids First Mission to orbit two different bodies

Getting There

Vesta’s Huge Crater