Chapter 27Chapter 27

Planets Planets of the Solar System of the Solar System

Standards: 1b Students know the Standards: 1b Students know the evidence from Earth and Moon rocks evidence from Earth and Moon rocks indicates that the Solar System was indicates that the Solar System was formed from a Nebula cloud of dust and formed from a Nebula cloud of dust and gas approximately 4.6 billion years ago gas approximately 4.6 billion years ago (bya). 1c Students know the evidence (bya). 1c Students know the evidence from geological studies of Earth and other from geological studies of Earth and other planets suggest that the early Earth was planets suggest that the early Earth was very different from Earth today.very different from Earth today.

VocabularyVocabulary

Solar SystemSolar System: : The Sun and all of the planets The Sun and all of the planets and other bodies that travel around it.and other bodies that travel around it.

PlanetPlanet: any of the primary bodies that orbit: any of the primary bodies that orbit the Sun; a similar body that orbits another the Sun; a similar body that orbits another star.star.

Solar NebulaSolar Nebula: a rotating cloud of dust and : a rotating cloud of dust and gas from which the sun and planets formed; gas from which the sun and planets formed; also any nebula from which stars and planets also any nebula from which stars and planets form.form.

PlanetismalPlanetismal: a small body from which a : a small body from which a planet originated in the early stages of planet originated in the early stages of development of the solar system.development of the solar system.

Learning GoalsLearning Goals

SWBAT:SWBAT: Describe how the Solar System was Describe how the Solar System was

formed.formed. Compare early models of solar system Compare early models of solar system

formation to recent models.formation to recent models. Use Kepler’s law to show to orbits Use Kepler’s law to show to orbits

move.move. Compare contrast Early Earth to Compare contrast Early Earth to

Present Earth. Present Earth.

How was the Solar How was the Solar System Formed?System Formed? The The Solar SystemSolar System consists of the consists of the

Sun and all the planets and other Sun and all the planets and other bodies that orbit around it. Planets bodies that orbit around it. Planets are large bodies that orbit the sun.are large bodies that orbit the sun.

1600-1700: 1600-1700: Planetismal TheoryPlanetismal Theory 1796: Pierre-Simon marquis de 1796: Pierre-Simon marquis de

Laplace introduced Laplace introduced Solar Nebula Solar Nebula TheoryTheory

Youtube:Formation of Solar System (Ignite)Youtube:Formation of Solar System (Ignite)

Solar Nebula Solar Nebula TheoryTheory Sun and Planets formed at about the same Sun and Planets formed at about the same

time out of a cloud of rotating gas and dust time out of a cloud of rotating gas and dust called a nebula.called a nebula.

Matter from the Universe gathers into cloudMatter from the Universe gathers into cloud 5 bya: Cloud forms when a supernova 5 bya: Cloud forms when a supernova

explodes. Under intense gravity and explodes. Under intense gravity and pressure caused the center of the solar pressure caused the center of the solar nebula to become hotter and denser. At 10 nebula to become hotter and denser. At 10 million degrees fusion begins and the Sun million degrees fusion begins and the Sun is formed. The sun is composed of 99% of is formed. The sun is composed of 99% of the matter from the solar nebula.the matter from the solar nebula.

Our Solar SystemOur Solar System

1.1. Explosion of Explosion of Super novaSuper nova2. Cloud of dust and 2. Cloud of dust and

gas condense and gas condense and form hot dense form hot dense center: Suncenter: Sun

3. Heavy materials left 3. Heavy materials left over orbit the sun, over orbit the sun, collide and form collide and form innerplanets.innerplanets.

4. Gases float farther 4. Gases float farther away, frozen and away, frozen and collide to form collide to form outer Planets.outer Planets.

5. Planets orbit our sun 5. Planets orbit our sun making up our making up our solar system.solar system.

How did Planets Form?How did Planets Form?

While the While the SunSun waswasforming in the centerforming in the centerof the solar nebulaof the solar nebulaPlanets were formingPlanets were formingin the outerin the outerRegions.Regions.PlanetismalsPlanetismals:small :small Bodies from whichBodies from whichA planet originated.A planet originated.Some Planetismals Some Planetismals collide and through collide and through gravity formgravity formProtoplanetsProtoplanets..

Formation of Formation of Inner Inner PlanetsPlanets Features of the newly formed planets Features of the newly formed planets

depends on the distance from the sun!depends on the distance from the sun! The four closest planets: Mercury,Venus, The four closest planets: Mercury,Venus,

Earth and Mars contain heavy elements Earth and Mars contain heavy elements such as Iron and Nickel. Also called such as Iron and Nickel. Also called Terrestrial Planets.Terrestrial Planets.

These planets lose their gases because These planets lose their gases because gravity is not strong enough to hold gas.gravity is not strong enough to hold gas.

Dense Materials sink to the center of the Dense Materials sink to the center of the planets. The planets form layers.planets. The planets form layers.

Inner planets: Solid, Rocky , Dense, Hotter!Inner planets: Solid, Rocky , Dense, Hotter!

The Outer PlanetsThe Outer Planets

Jupiter, Saturn, Uranus, and NeptuneJupiter, Saturn, Uranus, and Neptune Formed in colder region of solar nebula.Formed in colder region of solar nebula. Far from the Sun and very cold!Far from the Sun and very cold! Did not lose lighter elements such as Did not lose lighter elements such as

Hydrogen and Helium, or ice, methane Hydrogen and Helium, or ice, methane ice and ammonia ice.ice and ammonia ice.

Referred to as the gas planets, low Referred to as the gas planets, low density. Jupiter, only 24% of Earth’s density. Jupiter, only 24% of Earth’s density but 11 times the diameterdensity but 11 times the diameter

Solar System ReviewSolar System Review

Students always ask “How come Students always ask “How come Pluto isn’t a Planet anymore”Pluto isn’t a Planet anymore”

http://www.youtube.com/watch?http://www.youtube.com/watch?v=mtKNH2Y2OJM&feature=fvwv=mtKNH2Y2OJM&feature=fvw

Formation of Solid Formation of Solid EarthEarth

Early Solid Earth: How did the Early Solid Earth: How did the Earth form? What does Earth form? What does differentiation have to do with it?differentiation have to do with it?

How does the Present solid Earth How does the Present solid Earth contribute to the Atmosphere.contribute to the Atmosphere.

Formation of Earth’s Formation of Earth’s AtmosphereAtmosphere

What happened to Hydrogen and What happened to Hydrogen and Helium that were present in the early Helium that were present in the early formation of the Earth?formation of the Earth?

What role does the Solar Wind and What role does the Solar Wind and Gravity play in the atmosphere Gravity play in the atmosphere forming?forming?

Describe the benefits of outgassing.Describe the benefits of outgassing. How does Ozone protect us?How does Ozone protect us? How did early organisms increase the How did early organisms increase the

amount of oxygen in the air?amount of oxygen in the air?

Formation of the Formation of the OceansOceans

Where did the water from the Where did the water from the oceans come from?oceans come from?

Describe the process of Fresh Describe the process of Fresh water to Salt water.water to Salt water.

What are salt precipitates?What are salt precipitates? What are the effects of the What are the effects of the

atmosphere from the oceans?atmosphere from the oceans?

Section 2 Section 2 Models of the Models of the Solar SystemSolar System

Geo-Centric Model: 2,000 years Geo-Centric Model: 2,000 years ago Aristotle proposes Earth ago Aristotle proposes Earth Centered model of solar system.Centered model of solar system.

Ptolemy’s Model:Ptolemy’s Model:

Helio-Centric ModelHelio-Centric Model

1543, Polish Astronomer, 1543, Polish Astronomer, Nicholaus Copernicus proposes Nicholaus Copernicus proposes Helio-Centric Model.Helio-Centric Model.

Kepler’s LawsKepler’s Laws

Detailed observations of patterns of starst Detailed observations of patterns of starst through improved telescopes, led to through improved telescopes, led to Kepler’s development of 3 laws.Kepler’s development of 3 laws.

11stst Law: Law of Ellipses. States each Law: Law of Ellipses. States each planet orbits the sun in an elliptical planet orbits the sun in an elliptical pattern.pattern.

Ellipse: a closed curve whose shape is Ellipse: a closed curve whose shape is determined by 2 points,determined by 2 points,

foci.foci.Eccentricity: measure of the ellipseEccentricity: measure of the ellipseCircular orbit e=0Circular orbit e=0

22ndnd Law LawLaw of Equal AreasLaw of Equal Areas

Describes the speed of objects which Describes the speed of objects which travel at different points in their orbits.travel at different points in their orbits.

Q: When do planets travel at their Q: When do planets travel at their fastest speed? fastest speed?

A: When they are closest to the SunA: When they are closest to the SunA line from the center of the sund to the A line from the center of the sund to the

center of the object sweeps through center of the object sweeps through equal areas in equal periods of time.equal areas in equal periods of time.

33rdrd Law LawLaw of PeriodsLaw of Periods

Third law describes the Third law describes the relationship between the average relationship between the average distance of a planet from the sun distance of a planet from the sun and the orbital period of the and the orbital period of the planet.planet.

Orbital Period: the time it takes Orbital Period: the time it takes for a planet to complete one orbit.for a planet to complete one orbit.

Distance measured in Distance measured in Astronomical Units: AUAstronomical Units: AU

Animation: Kepler’s Animation: Kepler’s LawsLaws http://www.physics.sjsu.edu/http://www.physics.sjsu.edu/

tomley/Kepler12.htmltomley/Kepler12.html