Mystery of odd Wisconsin rock formations solvedJuliet Williams,  Associated Press

ROCK ELM, WIS. -- The muddy brown hills and rolling farmland at first look liketypical Wisconsin. Farm fields and a bubbling brook yield to rocky outcrops and rows oftrees.But scientists years ago saw something different about those rocks and concluded that anancient catastrophic event had occurred, although what it was remained a mystery.Now they believe they know: A 650- to 700-foot-wide meteorite crashed to Earth atspeeds as high as 67,500 miles per hour 450 million years ago.The impact dislodged rocks and created a massive hole about 4 miles in diameter and 600feet deep in an area called Rock Elm, 70 miles southeast of the Twin Cities, threescientists state in an article published in the Geological Society of America Bulletin.Over time, shale, dirt and sediment filled the crater to make the site virtuallyindistinguishable from the surrounding land. It's believed that a shallow sea coveringWisconsin at the time of the impact probably blunted the meteorite's effect.

Meteorite caused rock upheavalsJanet Hostetter

Associated Press

April 27, 2004CRATER0427

Bit of Administration ….Bit of Administration ….

• Washburn ObservatoryWashburn Observatory– Wednesday, after dusk for a few hoursWednesday, after dusk for a few hours

• ReadingReading– Chapter 24, Chapter 14 recommendedChapter 24, Chapter 14 recommended

• Discussion SectionDiscussion Section– Web-lecture in advance of sectionWeb-lecture in advance of section

• 2 pts extra credit for evaluation2 pts extra credit for evaluation

• 3 pt extra credit quiz3 pt extra credit quiz

• responsible for materialresponsible for material

THE EXTRA-SOLAR PLANET PROJECT • Phase 1: Last week’s quiz.

• Phase 2 : A Web-Lecture on Extra-Solar Planets.– Learn about extra-solar planets and have opportunity to earn 5 pts extra credit.

• 2 pts for evaluation questions• 3 pts for success on quiz

– Preparation for next week’s discussion sections (5/3-5/7).– Access: http://eteach.engr.wisc.edu/meibom/espp/index.html– Speed: 300 Kbps, 100 Kbps, and 37 Kbps.

• The hardware requirements for viewing the lecture are:– A computer with connection to the Internet.– Computer speakers or headphones.

• The software requirements for viewing the lecture are:– Windows Operating System.– Internet Explorer version 5.5 or later.– Power Point 2002 or later ("Power Point Animation plug-in").

• Campus computer-labs:– http://www.doit.wisc.edu/computerlabs/index.asp– Bring headphones!

Asteroids, Comets, Meteors, and PlutoAsteroids, Comets, Meteors, and Pluto

Primordial Icy PlanetesimalsPrimordial Icy Planetesimals

Fragmented Icy Planetesimals (KBOs)Fragmented Icy Planetesimals (KBOs)

Rocky PlanetesimalsRocky Planetesimals

Icy PlanetesimalsIcy Planetesimals

Jupiter FormsJupiter Forms

Oort CloudOort Cloud

Kuiper BeltKuiper Belt

SednaSedna

Asteroids, Comets, Meteors, and PlutoAsteroids, Comets, Meteors, and Pluto

• SummarySummary• AsteroidsAsteroids

• Rocky PlanetesimalsRocky Planetesimals• CometsComets

• Long - Period = Icy PlanetesimalsLong - Period = Icy Planetesimals• Short - Period = Fragmented KBOsShort - Period = Fragmented KBOs

• Pluto, Sedna, Triton, Kuiper Belt ObjectsPluto, Sedna, Triton, Kuiper Belt Objects• Icy PlanetesimalsIcy Planetesimals

• MeteorsMeteors• Processed Iron and Stony MeteoritesProcessed Iron and Stony Meteorites Fragmented asteroidsFragmented asteroids• Meteor ShowersMeteor Showers Fragmented cometsFragmented comets• Primitive Meteors = Rocky PlanetesimalsPrimitive Meteors = Rocky Planetesimals

Asteroids, Comets, Meteors, and PlutoAsteroids, Comets, Meteors, and Pluto

Asteroids, Comets, Meteors, and PlutoAsteroids, Comets, Meteors, and Pluto

• MeteorsMeteors• Showers - debris of old cometsShowers - debris of old comets

Earth orbitEarth orbit

Past CometPast Comet

Asteroids, Comets, Meteors, and PlutoAsteroids, Comets, Meteors, and Pluto

• MeteorsMeteors• Types - Processed MeteoritesTypes - Processed Meteorites

• Stony MeteoritesStony Meteorites• 93%93%• Just like crust of EarthJust like crust of Earth

• Iron MeteoritesIron Meteorites• 6 %6 %• Crystallization patterns => long cooling timesCrystallization patterns => long cooling times

Asteroids, Comets, Meteors, and PlutoAsteroids, Comets, Meteors, and Pluto

• MeteorsMeteors• Types - Primitive MeteoritesTypes - Primitive Meteorites

• Stony, with trace of pure metallic flakesStony, with trace of pure metallic flakes• Carbonaceous chondritesCarbonaceous chondrites

• Carbon compounds, and even waterCarbon compounds, and even water

Life in the Solar SystemLife in the Solar System• Arguments for Life as High ProbabilityArguments for Life as High Probability

• Organic molecules form easilyOrganic molecules form easily• Carbonaceous ChondritesCarbonaceous Chondrites• Allende Meteorite 2/8/69, 1:05 AMAllende Meteorite 2/8/69, 1:05 AM

Calcium-Aluminum Calcium-Aluminum Inclusions (CAIs)Inclusions (CAIs)

ChondrulesChondrules(Amino Acids)(Amino Acids)

Life in the Solar SystemLife in the Solar System

• Arguments for LifeArguments for Life• Organic molecules form easilyOrganic molecules form easily

Life in the Solar SystemLife in the Solar System• Arguments for Life as High ProbabilityArguments for Life as High Probability

• Organic molecules form easilyOrganic molecules form easily• Life occurred quickly on Earth - < 3.85 billion yearsLife occurred quickly on Earth - < 3.85 billion years

3.5 billion yr old3.5 billion yr old

Stromatolites (cyanobacteria)Stromatolites (cyanobacteria)

Life in the Solar SystemLife in the Solar System• Arguments for Life as High ProbabilityArguments for Life as High Probability

• Organic molecules form easilyOrganic molecules form easily• Life occurred quickly on Earth - < 3.85 billion yearsLife occurred quickly on Earth - < 3.85 billion years

4.4 billion yr old zircon4.4 billion yr old zircon

high oxygen isotope ratioshigh oxygen isotope ratios

cool water on Earth!cool water on Earth!

Life in the Solar SystemLife in the Solar System

• Arguments for Life as High ProbabilityArguments for Life as High Probability• Organic molecules form easilyOrganic molecules form easily• Life occurred quickly on Earth - < 3.85 billion yearsLife occurred quickly on Earth - < 3.85 billion years• Life can exist in a wide range of conditionsLife can exist in a wide range of conditions

Life in the Solar SystemLife in the Solar System• Life on Mars ?Life on Mars ?

• Flowing water and warm conditions for ≈ 1 byrFlowing water and warm conditions for ≈ 1 byr• Extensive volcanosExtensive volcanos

• Martian meteoritesMartian meteorites• ALH84001ALH84001

magnetite crystalsmagnetite crystals

Life in the Solar SystemLife in the Solar System• Life on Mars ?Life on Mars ?

• Flowing water and warm conditions for ≈ 1 byrFlowing water and warm conditions for ≈ 1 byr• Extensive volcanosExtensive volcanos

• Martian meteoritesMartian meteorites

Life in the Solar SystemLife in the Solar System

• Life on Europa ?Life on Europa ?• Icy crustIcy crust• Tidal heatingTidal heating

Liquid oceansLiquid oceansVolcanic ventsVolcanic vents

Life in the Solar SystemLife in the Solar System

• Life on EuropaLife on Europa• Icy crustIcy crust• Tidal heatingTidal heating

Liquid oceansLiquid oceansVolcanic ventsVolcanic vents