geol3045: planetary geology lysa chizmadia 16 jan 2007 the origin of our solar system lysa chizmadia...
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GEOL3045: Planetary Geology
GEOL3045: Planetary Geology
Lysa Chizmadia16 Jan 2007
The Origin of Our Solar System
Lysa Chizmadia16 Jan 2007
The Origin of Our Solar System
Images from: http://csep10.phys.utk.edu/astr161/lect/solarsys/nebular.html
Interstellar Cloud CollapseInterstellar Cloud Collapse Initially, Interstellar Cloud of gas
and/or dust Interstellar cloud of gas and dust
disturbed and collapsed under its own gravity Probably due to shock waves from
near-by supernova
As collapses, cloud heats up, starts to rotate and compresses in center T enough to vaporize dust Takes ~ 100,000 years (100 ka)
Initially, Interstellar Cloud of gas and/or dust
Interstellar cloud of gas and dust disturbed and collapsed under its own gravity Probably due to shock waves from
near-by supernova
As collapses, cloud heats up, starts to rotate and compresses in center T enough to vaporize dust Takes ~ 100,000 years (100 ka)
Protostar & Accretion DiskProtostar & Accretion Disk Due to rotation, nebula flattens
into disk Center compresses into
protostar & rest of gas rotates around it Gas flows into protostar,
protostar grows into star Centrifugal forces keep
some gas from falling in Accretion disk
Due to rotation, nebula flattens into disk
Center compresses into protostar & rest of gas rotates around it Gas flows into protostar,
protostar grows into star Centrifugal forces keep
some gas from falling in Accretion disk
Images from: http://en.wikipedia.org/wiki/Solar_System and http://csep10.phys.utk.edu/astr161/lect/solarsys/nebular.html
Orion Nebula
Thermodynamic CondensationThermodynamic Condensation Gas starts to cool, eventually
condenses into solids First solids = most refractory
( T) E.g. Ca, Al, Ti oxides with
some silicates I.e. CAIs (Ca, Al-rich
inclusions) Thermodynamic
condensation With T, less refractory elements
condense Mg > Si > Cr > Mn > Na > K > Fe
> Ni > S
Gas starts to cool, eventually condenses into solids First solids = most refractory
( T) E.g. Ca, Al, Ti oxides with
some silicates I.e. CAIs (Ca, Al-rich
inclusions) Thermodynamic
condensation With T, less refractory elements
condense Mg > Si > Cr > Mn > Na > K > Fe
> Ni > S Image from: Davis and Richter (2007) Treatise of Geochemistry vol. 1, chpt 15, p410
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Ca, Al-rich InclusionsCa, Al-rich Inclusions Ca, Al, Ti, Si, Mg
Oxides & Silicates
T >1300 K Pb-Pb dating
4.559 + 0.004 Ga Confirmed by
Rb-Sr & Sm-Nd dating
26Al excess > 2 Ma older
than all other materials
Ca, Al, Ti, Si, Mg Oxides &
Silicates T >1300 K
Pb-Pb dating 4.559 + 0.004 Ga Confirmed by
Rb-Sr & Sm-Nd dating
26Al excess > 2 Ma older
than all other materials Images from personal
archive
Dust BallsDust Balls Solids start to accrete together into dust balls Solids start to accrete together into dust balls
Image from: http://www.psi.edu/hartmann/pic-cat/pages/100_Solar_System_Origin.html
Chondrule FormationChondrule Formation Transient heating events form chondrules & igneous CAIs Transient heating events form chondrules & igneous CAIs
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Images from: Jones (1990) Geochemica et Cosmochimica Acta v54 p1785 and http://www.psrd.hawaii.edu/Mar00/flashHeating.html
Run-Away GrowthRun-Away Growth Solids continue to accrete
into planetessimals Run-away growth
Planetessimals grow into planetary embryos Gas blown out of system
due to high solar winds Planetary embryos grow into
planets Moon to Mars sized 10-100 Ma
10-15 planetary embryos in inner solar system
Solids continue to accrete into planetessimals Run-away growth
Planetessimals grow into planetary embryos Gas blown out of system
due to high solar winds Planetary embryos grow into
planets Moon to Mars sized 10-100 Ma
10-15 planetary embryos in inner solar system
Images from: http://en.wikipedia.org/wiki/Solar_System and http://csep10.phys.utk.edu/astr161/lect/solarsys/nebular.html
SummarySummary 1) Solar System formed from collapse of
interstellar molecular cloud Heats up and vaporizes all dust
2) As nebula cools down, condensation of solid materials Most refractory elements first, followed by more and
more volatile elements
3) Solids accrete in run-away growth Dust balls Planetessimals Planetary Embryos Planets
1) Solar System formed from collapse of interstellar molecular cloud Heats up and vaporizes all dust
2) As nebula cools down, condensation of solid materials Most refractory elements first, followed by more and
more volatile elements
3) Solids accrete in run-away growth Dust balls Planetessimals Planetary Embryos Planets