FORMATION OF THE SOLAR SYSTEM

Nebular Theory  Older Theory  Solar nebula  Fragments spins faster and faster flattening into a disk- like feature  Formed Sun and Planets  Spinning = almost perfect circle orbits  Flaw  Computer models show clumps would break apart not get bigger and bigger.  needed to revise the theory

Condensation Theory  Newer Theory  Interstellar Dust  From dead stars  Helped to: cool the cloud of gas making it easier to collapse the disk speed up the process of collecting atoms to form planets  Condensation nuclei Microscopic platforms to which other atoms can attach, forming larger balls of matter.

PLANET FORMATION

Stage 1  Accretion  Dust forms condensation nuclei = clumps = bigger clumps…  By collision and sticking  End  Hydrogen and Helium  Millions planetesimals Objects the size of small moons Gravitational fields large enough to effect their neighbors

Stage 2  Collision of planetesimals due to gravity = Protoplanets  Protoplanets  Build-up of matter that will become the planets  Collision of planetesimals and protoplanets  Produced fragments, which some became asteroids and comets  100 million years  8 protoplanets  Dozen of protomoon  Protosun (protostar)  Another billion years = solar system similar to ours  Extreme meteorite bombardment

DIFFERENTIATION OF THE SOLAR SYSTEM Inner planets vs. Outer planets

Factors that influence planet formation  Temperature  Hotter in the center and cooler on the outside  Distance Metallic grains = Mercury’s orbit 1 AU = silicate grains 3 or 4 AU = water ice could exist 5 AU = water vapor, ammonia, and methane  Density  More dense towards the center  Gravity was affecting it all

Inner Planet  Terrestrial Planets  Mercury, Venus, Earth, and Mars  Dust breaking down into atoms then reformed into new dust (grains)  Heavier elements abundant  Silicon, Iron, Magnesium, Aluminum combined with oxygen to form rocky materials  Lack of lighter elements  The comet bombardment of planets = water

Outer Planets  Jovian Planets  Jupiter, Saturn, Uranus, and Neptune  Cores formed under cooler conditions = low ice dense material  Accretion began soon after disk formation  Grew large enough to accrete grains and then gases from the nebula = hydrogen rich planets

Review Video  Formation of Solar System Formation of Solar System   Questions: 1. Why are asteroids so important? They help us understand how our solar system began 2. Where did Iron 60 come from? Massive stars – supernova 3. What are the two ideas of how our solar system got started? Supernova shockwave and gentle shockwaves from a Massive star

FORCE BEHIND THE FORMATION Gravity

Lab: Balloon on a String  Hypothesis: What direction do you think the balloons would travel in if they were released while spinning (circle, diagonal, straight line, etc…) and why?  When we are outside draw in your science journals what you see happen.  Is there anything you observed that would change your inference/hypothesis? If so what?

Lab Continue  Listen to reading  What are the two forces that hold our solar system together?  Gravity and inertia  In the demo what was what?  String:  The Balloon:  The person:  The release of the balloon:  What would happen to all the planets if the Sun disappeared?

Newton’s 1 st Law: Inertia  (Notes Found in your History Notes under Newton)  Inertia: the tendency for an object to keep moving in the same direction and speed unless acted upon by an outside force.  More mass = greater inertia and the more force is needed to change its motion

Gravity  Gravitational review (if time)  ture=related ture=related  What object in our solar system has the largest amount of gravity? Why?  Sun because it has the most mass (99.9%)

Laws of Universal Gravitation  (Notes Found in your History Notes under Newton)  Gravitational force: things with mass exerts attraction on other masses  “ The mutual gravitational attraction of the Sun and the planets, as expressed by Newton’s law of gravity, is responsible for the observed planetary orbits” (McMillan 37).  The Sun pulls the planets changing the planets forward motion into a curved path

Einstein's Theory of Relativity  “Time and space, according to Einstein's theories of relativity, are woven together, forming a four- dimensional fabric called "space-time." The mass of Earth dimples this fabric, much like a heavy person sitting in the middle of a trampoline. Gravity, says Einstein, is simply the motion of objects following the curvaceous lines of the dimple” (Dr. Tony Phillips | Credit: Tony Phillips  Trap demo 

FUN FACTS

An inventory of the Solar System  1 sun  8 planets  5 dwarf planets  166 moons  7 asteroids  more than 100 Kuiper belt objects larger than 300 km (200 miles) in diameter  10s of thousands of smaller asteroids and Kuiper belt objects  Countless comets few km in diameter  Numerous meteoroids less than 100 m across  Sun makes up 99.9% of the solar systems mass

Videos  Time Travel Time Travel  8&feature=related 8&feature=related  Planet Review (if time) 