General Physical Science - Cameron Universitykeithv/gps/GPS_16.pdf · Conjunction 2 planets lined up with Sun Inferior planets •• Same side Same side – inferior conjunction

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General Physical General Physical ScienceScience

Chapter Chapter 1616

The Solar SystemThe Solar System

The Solar System: An OverviewThe Solar System: An Overview

�� The solar system is a complex system of The solar system is a complex system of

moving masses held together by moving masses held together by gravitational forces.gravitational forces.

�� 8 major planets8 major planets

•• WanderersWanderers

�� 3 dwarf planets3 dwarf planets

�� More than160 More than160 moonsmoons

�� Asteroids, comets meteoroidsAsteroids, comets meteoroids

�� Solar windSolar wind

•• Charged particles, gases, interstellar dustCharged particles, gases, interstellar dust


�� Geocentric ModelGeocentric Model

�� Everything rotates around the earthEverything rotates around the earth

•• Pushed by the Catholic ChurchPushed by the Catholic Church

•• Very difficult to explain some observed motionsVery difficult to explain some observed motions

�� Heliocentric ModelHeliocentric Model

�� CopernicusCopernicus

�� Revolves around the sunRevolves around the sun

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�� TychoTycho BraheBrahe

�� Known for accurate measurement of the Known for accurate measurement of the positions of stars and positions of stars and planetsplanets

•• Unaided eye!Unaided eye!

�� Data analyzed by Data analyzed by KeplerKepler

�� KeplerKepler then used this data to devise his Laws then used this data to devise his Laws

of Planetary Motion.of Planetary Motion.

Laws of Planetary MotionLaws of Planetary Motion

�� First Law (Law of First Law (Law of Elliptical Motion)Elliptical Motion)

�� All planets move in All planets move in elliptical paths around elliptical paths around the Sun with the Sun the Sun with the Sun as one focus of the as one focus of the ellipseellipse

�� Major axisMajor axis

�� SemiSemi--major axismajor axis

•• For Earth, semi major For Earth, semi major

axis = 1 AUaxis = 1 AU


�� Second Law (Law of Equal Areas)Second Law (Law of Equal Areas)

�� An imaginary line joining the planet and the An imaginary line joining the planet and the sun sweeps an equal area in an equal period sun sweeps an equal area in an equal period

of time.of time.

�� PerihelionPerihelion

•• Point that planet is closest to the sun (Jan. 4)Point that planet is closest to the sun (Jan. 4)

�� AphelionAphelion

•• Point that planet is farthest from the Sun (July 5)Point that planet is farthest from the Sun (July 5)

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�� Third Law (Harmonic Law)Third Law (Harmonic Law)�� The square of the sidereal period of a The square of the sidereal period of a

planet is proportional to it’s semiplanet is proportional to it’s semi--major major axis.axis.

�� SiderealSidereal•• Time for one revolution around the SunTime for one revolution around the Sun•• 1 year for earth1 year for earth

�� TT22 = kR= kR33

•• R = length of semiR = length of semi--major axismajor axis•• T = timeT = time•• When T in years, R in AU, then k = 1 yearWhen T in years, R in AU, then k = 1 year22 / /

AUAU33

ExampleExample

�� Calculate the period of a planet whose Calculate the period of a planet whose

orbit has a semiorbit has a semi--major axis of 1.52 AUmajor axis of 1.52 AU

�� TT22 = kR= kR33

�� R = 1.52 AUR = 1.52 AU

�� k = 1 yk = 1 y22 / AU/ AU33

�� TT22 = (1) (1.52)= (1) (1.52)33 (y(y22 AUAU33 / AU/ AU33))

�� TT22 = 3.51 y= 3.51 y22

�� T = 1.87 yT = 1.87 y

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The Solar System and The Solar System and

Planetary MotionPlanetary Motion�� Learning GoalsLearning Goals

�� Name some early astronomers and outline some Name some early astronomers and outline some theories concerning the historical development of theories concerning the historical development of astronomy as it relates to the solar system.astronomy as it relates to the solar system.

�� State and explain State and explain Kepler’sKepler’s laws of planetary motion.laws of planetary motion.

�� Questions: 1 Questions: 1 –– 44

�� Exercises: 1 Exercises: 1 –– 11 odd11 odd

Major Planet Classifications and Major Planet Classifications and

OrbitsOrbits

�� Galileo Galileo GalileiGalilei

�� First to observe the Moon through a telescopeFirst to observe the Moon through a telescope

�� Observed 4 moons around JupiterObserved 4 moons around Jupiter

•• First to First to proveprove Earth not the only center of motion Earth not the only center of motion in the universein the universe..

•• Showed that Venus had phases similar to the Showed that Venus had phases similar to the Moon.Moon.


OrbitsOrbits�� IssacIssac NewtonNewton

�� Incorporated work of Copernicus, Incorporated work of Copernicus, KeplerKepler, and , and Galileo to formulate gravitational theoryGalileo to formulate gravitational theory

�� Invented calculusInvented calculus

•• Used to explain Used to explain Kepler’sKepler’s First LawFirst Law

•• Used Conservation of Angular Momentum to Used Conservation of Angular Momentum to explain explain Kepler’sKepler’s 22ndnd LawLaw

�� Mass of the Solar SystemMass of the Solar System

�� 99.87% of the mass is the Sun99.87% of the mass is the Sun

•• More than ½ of remaining mass is JupiterMore than ½ of remaining mass is Jupiter

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Major Planet Major Planet ClassificationClassification

�� Inferior planetsInferior planets�� Planets with their orbit inside that of Earth.Planets with their orbit inside that of Earth.�� Mercury, VenusMercury, Venus

�� Superior planetsSuperior planets�� Planets with their orbit outside that of Earth.Planets with their orbit outside that of Earth.

�� Mars, Jupiter, Saturn, Uranus, Neptune, PlutoMars, Jupiter, Saturn, Uranus, Neptune, Pluto

�� Terrestrial (EarthTerrestrial (Earth--like) planetslike) planets�� Mercury, Venus, Earth, Mercury, Venus, Earth, MarsMars

�� Jovian (JupiterJovian (Jupiter--like) planetslike) planets�� Jupiter, Saturn, Uranus, NeptuneJupiter, Saturn, Uranus, Neptune

Planetary MotionPlanetary Motion

�� Prograde motionPrograde motion�� Counter clockwise as viewed from the North Counter clockwise as viewed from the North

PolePole

�� All planetary orbitsAll planetary orbits

�� Most planetary rotationMost planetary rotation

�� Retrograde motionRetrograde motion�� Clockwise as viewed from the North PoleClockwise as viewed from the North Pole

�� Venus, Uranus rotationVenus, Uranus rotation

Relative Size of the Planets and Relative Size of the Planets and

the Sunthe Sun

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OrbitsOrbits�� Sidereal PeriodSidereal Period

�� Time for one orbit relative to a distant starTime for one orbit relative to a distant star

�� ConjunctionConjunction

�� 2 planets lined up with Sun2 planets lined up with Sun

�� Inferior planetsInferior planets

•• Same side Same side –– inferior conjunctioninferior conjunction

•• Opposite Side Opposite Side –– superior conjunctionsuperior conjunction

�� Superior PlanetsSuperior Planets

•• Same side Same side –– conjunctionconjunction

•• Opposite sides Opposite sides –– opposition opposition

Conjunction and OppositionConjunction and Opposition


�� Learning GoalsLearning Goals�� Describe Describe the composition, structure, and motions of the composition, structure, and motions of

the planets.the planets.

�� Questions: Questions: 5 5 –– 7 7

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The Planet EarthThe Planet Earth

�� UniqueUnique

�� Large amounts of Large amounts of surface watersurface water

•• NOT only body with NOT only body with

waterwater

�� Atmosphere contains Atmosphere contains oxygenoxygen

�� Temperate climateTemperate climate

�� Living organismsLiving organisms

•• As far as we knowAs far as we know

EarthEarth

�� Oblate Oblate spheroidspheroid

�� Slightly larger diameter at the equator than from pole Slightly larger diameter at the equator than from pole to pole (43 km)to pole (43 km)

�� due to Earth’s rotationdue to Earth’s rotation

�� one part in 300 (1 inch in 25 ft)one part in 300 (1 inch in 25 ft)

�� AlbedoAlbedo 0.330.33

�� 2 separate motions2 separate motions

�� rotationrotation

�� revolution revolution

EarthEarth

�� Tilted 23.5Tilted 23.5OO from orbital planefrom orbital plane�� tilt plus revolution leads to seasonstilt plus revolution leads to seasons

�� FocaultFocault PendulumPendulum�� Proved rotation of the EarthProved rotation of the Earth

•• Released with no lateral motionReleased with no lateral motion

•• Direction of pendulum swing appears to changeDirection of pendulum swing appears to change

•• Apparent change due to Earth’s rotation.Apparent change due to Earth’s rotation.

•• At the North pole rotation is 90At the North pole rotation is 90OO in 6 hoursin 6 hours

•• Direction is constant relative to external referenceDirection is constant relative to external reference

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Focault’s Focault’s

PendulumPendulum

EarthEarth

�� ParallaxParallax

�� Apparent shift in Apparent shift in position of closer stars position of closer stars against background of against background of farther starsfarther stars

�� Simulate with finger Simulate with finger lined up with more lined up with more distant objectdistant object

�� Use to determine Use to determine distance from starsdistance from stars

EarthEarth

�� ParsecParsec

�� Distance to a star when it exhibits a parallax Distance to a star when it exhibits a parallax of 1 second (angular measurement 1/3600 of 1 second (angular measurement 1/3600

degree)degree)

�� Aberration Aberration of starlightof starlight

�� Apparent change in direction of light from starApparent change in direction of light from star

�� Snowflakes in snowstormSnowflakes in snowstorm

�� Raindrops in moving Raindrops in moving carcar

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Facts and FiguresFacts and Figures

EarthEarth

�� Learning GoalsLearning Goals

�� Identify some chemical and physical Identify some chemical and physical properties of the Earthproperties of the Earth

�� Define and explain Earth’s two major motions.Define and explain Earth’s two major motions.


The Terrestrial PlanetsThe Terrestrial Planets

�� Relatively smallRelatively small

�� Made up primarily of rocks and metalsMade up primarily of rocks and metals

�� High density (5 g/cmHigh density (5 g/cm33))

�� Solid SurfaceSolid Surface

�� Magnetic fieldsMagnetic fields

�� Relatively close to the SunRelatively close to the Sun

�� No ring systemsNo ring systems

�� Earth, Mars have moonsEarth, Mars have moons

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MercuryMercury

�� Shortest revolution Shortest revolution (88 days)(88 days)

�� Only visible at sunrise Only visible at sunrise or sunsetor sunset

�� Surface similar to the Surface similar to the MoonMoon�� absence of significant absence of significant

atmosphereatmosphere•• Surface temperature Surface temperature

varies from varies from -- 180180OOC to C to 430430OOCC

�� evidence that once evidence that once had thin atmospherehad thin atmosphere

Mercury Mercury –– Facts and FiguresFacts and Figures

VenusVenus

�� Closest to EarthClosest to Earth

�� Third brightest object Third brightest object in the skyin the sky

�� Very similar to EarthVery similar to Earth

�� Atmosphere 96% COAtmosphere 96% CO22

�� Surface temp 480Surface temp 480OOCC

•• Greenhouse EffectGreenhouse Effect

�� Surface pressure 90 Surface pressure 90 atmatm

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VenusVenus

�� Surrounded by cloudsSurrounded by clouds�� AlbedoAlbedo 0.780.78

�� Mostly HMostly H22SOSO44 / H/ H22OO

�� Sulfur dust gives yellow colorSulfur dust gives yellow color

�� Atmosphere rotational period 4 days (Retrograde)Atmosphere rotational period 4 days (Retrograde)

�� Planetary rotation 243 days (retrograde)Planetary rotation 243 days (retrograde)�� May have been struck during formationMay have been struck during formation

�� Surface mapped by Surface mapped by radarradar�� Many surface featuresMany surface features

�� Evidence of former volcanic activityEvidence of former volcanic activity

�� Most features about 400 million years oldMost features about 400 million years old

Venus Venus –– Facts and FiguresFacts and Figures

MarsMars

�� 1.5 x as far from the 1.5 x as far from the Sun as EarthSun as Earth

�� Tilted 24Tilted 24OO

�� Rotation 24.5 hoursRotation 24.5 hours

�� 687 day synodic 687 day synodic periodperiod

�� 2 small moons2 small moons�� Phobos (fear)Phobos (fear)

�� Deimois (panic)Deimois (panic)

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MarsMars

�� Moons are tideMoons are tide--lockedlocked�� Rotational period equals Rotational period equals synodicsynodic periodperiod

�� Same as Earth’s MoonSame as Earth’s Moon

�� Density = 3.9 g / cmDensity = 3.9 g / cm33

�� CrateredCratered�� ‘Canals’ ‘Canals’

�� Polar capsPolar caps�� Summer Summer -- HH22OO

�� Winter Winter -- HH22O and COO and CO22

MarsMars

�� Volcanic activityVolcanic activity�� Olympus MonsOlympus Mons

•• 24 km high24 km high�� Crater is 80 km and base is 600 kmCrater is 80 km and base is 600 km

•• Largest known volcano in the Solar SystemLargest known volcano in the Solar System

•• Earth Earth -- Mauna Loa about 9 Mauna Loa about 9 kmkm

�� Martian ExplorationMartian Exploration�� From 1976 From 1976 –– present!present!

MarsMars

�� VallesValles MarinerisMarineris

�� 400 km long400 km long

�� 6 km deep6 km deep

�� Thought to be stress Thought to be stress fracturefracture

�� Unmanned Unmanned explorationexploration

�� Viking I (1976)Viking I (1976)

�� Pathfinder (1997)Pathfinder (1997)

•• SojournerSojourner

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MarsMars

�� Evidence of fluid flow Evidence of fluid flow at one time!at one time!

�� Supported by findings Supported by findings of Mars Global of Mars Global

Surveyor (2000)Surveyor (2000)


�� Origins thought to be similar to Jovian Origins thought to be similar to Jovian

PlanetsPlanets

�� Predominant elements were H and HePredominant elements were H and He

�� Solar heat provided enough energy for these Solar heat provided enough energy for these gases to escapegases to escape

�� Left behind the highLeft behind the high--density rocky coredensity rocky core

Mars Mars –– Facts and FiguresFacts and Figures

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�� Learning GoalsLearning Goals

�� List and compare the physical characteristics List and compare the physical characteristics of the terrestrial planets.of the terrestrial planets.


The Jovian PlanetsThe Jovian Planets

�� Gas giantsGas giants

�� No solid surfaceNo solid surface

�� Low density (average 1.2 g/cmLow density (average 1.2 g/cm33))

•• About the density of waterAbout the density of water

�� Inner rock coreInner rock core

�� Lower temperatures did not allow H and Lower temperatures did not allow H and

He to escapeHe to escape

Significant Differences between Significant Differences between

Terrestrial and Jovian PlanetsTerrestrial and Jovian Planets

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JupiterJupiter

�� Largest PlanetLargest Planet

�� d = 1.3 g/cmd = 1.3 g/cm33

�� Liquid metallic Liquid metallic hydrogen with a rocky hydrogen with a rocky corecore

�� AtmosphereAtmosphere

�� ‘Bands’ on surface‘Bands’ on surface

�� HH22, He, CH, He, CH44, NH, NH33

�� Mean temp Mean temp ––148148OOCC

�� Great Red SpotGreat Red Spot

�� Perpetual stormPerpetual storm

JupiterJupiter

�� Shoemaker Shoemaker –– Levy 9Levy 9�� Comet fragments Comet fragments

smashed into Jupiter’s smashed into Jupiter’s atmosphereatmosphere

�� Visible from EarthVisible from Earth

�� Dark spots approx. Dark spots approx. size of the Earth!size of the Earth!

�� Jupiter also has a ring Jupiter also has a ring systemsystem�� Not visible from EarthNot visible from Earth

Jupiter’s RingsJupiter’s Rings

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Moons of JupiterMoons of Jupiter

�� 16 or more observed16 or more observed�� Difference is line between small moon and big Difference is line between small moon and big

rockrock

�� Four moons observed by Galileo in 1610Four moons observed by Galileo in 1610�� IoIo

�� EuropaEuropa

�� Ganymede (largest moon in Solar System)Ganymede (largest moon in Solar System)

�� CallistoCallisto

Jupiter Jupiter –– Facts and FiguresFacts and Figures

SaturnSaturn

�� Most prominent feature Most prominent feature is the ring systemis the ring system�� 3 ring systems3 ring systems

�� A, B, and CA, B, and C

�� Rings formed by tidal Rings formed by tidal forcesforces

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Saturn’s RingsSaturn’s Rings

�� Many individual Many individual ringletsringlets

�� Color is computer Color is computer enhancement of enhancement of

chemical composition.chemical composition.

�� Does have moonsDoes have moons

�� Largest is TitanLargest is Titan

TitanTitan

�� Only satellite known Only satellite known with a hazy with a hazy

atmosphereatmosphere

�� NN22 (about 90%)(about 90%)

�� Ar (less than 10%)Ar (less than 10%)

�� Methane and other Methane and other hydrocarbonshydrocarbons

Saturn Saturn –– Facts and FiguresFacts and Figures

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UranusUranus

�� Discovered in 1781Discovered in 1781

�� Internal structure different than Jupiter and Internal structure different than Jupiter and SaturnSaturn

�� Less massiveLess massive

�� Larger rocky coreLarger rocky core

�� Very thin ring systemVery thin ring system

�� Larger particlesLarger particles

�� Not much reflectionNot much reflection

UranusUranus

True Color RepresentationTrue Color Representation

Ring SystemRing System

Uranus Uranus –– Facts and FiguresFacts and Figures

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NeptuneNeptune

�� Twin of UranusTwin of Uranus

�� Found in part by Found in part by mathematical mathematical calculations based on calculations based on

disturbances in orbit disturbances in orbit of Uranusof Uranus

�� Dark spot similar to Dark spot similar to

Great Red Spot on Great Red Spot on JupiterJupiter

Rings of NeptuneRings of Neptune

�� Were predicted by Were predicted by blocking of starlightblocking of starlight

�� Observations were Observations were questionable.questionable.

�� Ring system Ring system confirmed with confirmed with Voyager 2Voyager 2

Neptune Neptune –– Facts and FiguresFacts and Figures

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The Jovian PlanetsThe Jovian Planets

�� Learning Goals:Learning Goals:

�� List and compare the properties of the Jovian List and compare the properties of the Jovian planets.planets.

�� Identify the major differences between the Identify the major differences between the terrestrial and Jovian planetsterrestrial and Jovian planets

�� Questions: 14 Questions: 14 –– 1717

The Dwarf PlanetsThe Dwarf Planets

�� Category added in 2006 by International Category added in 2006 by International

Astronomical UnionAstronomical Union

�� PlutoidsPlutoids

�� Must orbit sunMust orbit sun

�� Nearly round from selfNearly round from self--gravitygravity

�� Dominant body in it’s orbitDominant body in it’s orbit

CeresCeres

�� Between Mars and Between Mars and JupiterJupiter


�� Formerly classified as Formerly classified as an asteroidan asteroid

�� Smallest of the dwarf Smallest of the dwarf planetsplanets

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Ceres Ceres –– Facts and FiguresFacts and Figures

PlutoPluto

�� Most distant from Most distant from the Sunthe Sun

�� Discovered in 1930 Discovered in 1930 by observers in AZby observers in AZ

�� Some similarities to Some similarities to Uranus/NeptuneUranus/Neptune�� Not enough to Not enough to

classify as ‘Jovian”classify as ‘Jovian”

�� At times Pluto closer At times Pluto closer than Neptune!than Neptune!

CharonCharon

�� Satellite of PlutoSatellite of Pluto

�� Largest satellite Largest satellite relative to planet sizerelative to planet size

�� ½ size of Pluto½ size of Pluto


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Orbital PlaneOrbital Plane

Pluto Pluto –– Facts and FiguresFacts and Figures

ErisEris

�� Furthest from the SunFurthest from the Sun


�� Slightly larger than Slightly larger than

PlutoPluto

�� Very elliptical orbitVery elliptical orbit

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Eris Eris –– Facts and FiguresFacts and Figures

…and beyond?…and beyond?

�� KuiperKuiper BeltBelt

�� From Neptune to ErisFrom Neptune to Eris

�� Home for comets and Home for comets and cometarycometary materialmaterial

�� Exploration slated for 2015Exploration slated for 2015

�� Most distant object is Most distant object is SednaSedna

�� 90 AU / 75 AU axes90 AU / 75 AU axes

�� Termination shockTermination shock

�� Edge of solar systemEdge of solar system

�� Solar wind meets interstellar materialSolar wind meets interstellar material

The The Dwarf Dwarf PlanetsPlanets

�� Learning Goals:Learning Goals:

�� List and compare the properties of the List and compare the properties of the Dwarf Dwarf planetsplanets..

�� List List the physical properties of Plutothe physical properties of Pluto

�� Questions: Questions: 18, 1918, 19

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Origin of the Solar SystemOrigin of the Solar System

�� Solar Solar NebulaNebula�� About 4.5 billion years agoAbout 4.5 billion years ago

�� Began to condense under influence of it’s Began to condense under influence of it’s own gravityown gravity

�� Condensation nucleus now part of the SunCondensation nucleus now part of the Sun

�� Conservation of angular momentum Conservation of angular momentum began to cause nebula to spinbegan to cause nebula to spin�� Caused flatteningCaused flattening

•• Pizza doughPizza dough


�� Kepler’sKepler’s Third Law stated that outer Third Law stated that outer

material would rotate slowermaterial would rotate slower

�� Created ‘shear forces’Created ‘shear forces’

�� This matter began to condense into the This matter began to condense into the planetsplanets..


�� Formed ‘Formed ‘protoplanetsprotoplanets’’�� ProtoearthProtoearth probably 1000 x more massive probably 1000 x more massive

than the Earth todaythan the Earth today

�� Similar in composition to the Jovian planetsSimilar in composition to the Jovian planets

�� Heating of the terrestrial planets drove off Heating of the terrestrial planets drove off the gasesthe gases

�� Space was ‘thicker’ with dustSpace was ‘thicker’ with dust�� Shielded planets initially from solar energyShielded planets initially from solar energy

�� Became clear from planetary accumulation Became clear from planetary accumulation and solar wind transport.and solar wind transport.

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�� Learning Goal:Learning Goal:

�� Describe the theory for the origin of the solar Describe the theory for the origin of the solar system that is most widely accepted by system that is most widely accepted by

astronomers.astronomers.


Other Planetary SystemsOther Planetary Systems

�� Difficult to detect visuallyDifficult to detect visually

�� Reflected light washed out by light from starReflected light washed out by light from star

�� Observe other effectsObserve other effects

�� GravitationalGravitational

•• ‘Wobble’‘Wobble’

•• Doppler effectDoppler effect

�� Over 200 other planets have been Over 200 other planets have been detected indirectly!detected indirectly!

�� SpectroscopicallySpectroscopically determined water on one determined water on one exoplanetexoplanet

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Other Planetary SystemsOther Planetary Systems

�� Learning GoalLearning Goal

�� Describe the methods used to discover Describe the methods used to discover planets around other starsplanets around other stars

�� Questions: 22 Questions: 22 –– 23 23

�� Key Terms; Matching, Multiple Choice, Key Terms; Matching, Multiple Choice,

and Filland Fill--inin--thethe--Blank Questions; Visual Blank Questions; Visual

Connection and Applying your KnowledgeConnection and Applying your Knowledge

General Physical General Physical ScienceScience

Chapter Chapter 1616

The Solar SystemThe Solar System

Documents

General Physical Science - Cameron Universitykeithv/gps/GPS_16.pdf · Conjunction 2 planets lined up with Sun Inferior planets •• Same side Same side – inferior conjunction