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CH 25.5 Solar System Formation . Objectives: How did our solar system form? What evidence supports our ideas?. http://atropos.as.arizona.edu/aiz/teaching/nats102/mario/solar_system.html. Nebula Theory. The solar system formed fr om a cloud of dust and gas (nebula). 4.6 billion years ago
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CH 25.5 Solar System Formation Objectives: How did our solar system form? What evidence supports our ideas? http://atropos.as.arizona.edu/aiz/teaching/nats102/mario/solar_system.html
Nebula Theory The solar system formed froma cloud of dust and gas (nebula). 4.6 billion years ago Nebula produced by the explosion of a previous star.
Protoplanetary Disk Protoplanetary disk forms when gravity pulls particles and gas to the center. Disk begins to spin (possibly because of a shock wave from a “nearby” supernova. Gravity continues to contract the cloud to the center – making it spin faster (angular momentum … think ice skaters spinning) Protosunat center Sun when temperatures reach millions of degrees and NUCLEAR FUSION BEGINS. Nuclear fusion combines hydrogen atoms together to make helium and releases LOTS of ENERGY! Stars begin to shine! http://atropos.as.arizona.edu/aiz/teaching/nats102/mario/solar_system.html
Planets Grow by Accretion Accretion: Growth by colliding and sticking together Planetessimals(asteroid size) Protoplanets(moon size) Planets
Inner vs. Outer Inner Solar System = “Rocky” PlanetsHotter Metals & Rock condense (gas solid) @ higher temps. Outer Solar System = “Gas” Giants Colder Light gases like H; He; Ammonia; Methane; Water condense (gas solid ice crystals) @ cold temps.
Evidence to Support Sun is 99.9% of mass – in center. Planets all orbit in same plane. Planets orbit in same direction.